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Canadian Journal of Cardiology

Medical Management of Left Ventricular Assist Device Patients: A Practical Guide for the Nonexpert Clinician

Published:October 04, 2019DOI:https://doi.org/10.1016/j.cjca.2019.09.020

      Abstract

      Left ventricular assist devices (LVADs) provide short- or long-term circulatory support to improve survival and reduce morbidity in selected patients with advanced heart failure. LVADs are being used increasingly and now have expanded indications. Health care providers across specialties will therefore not only encounter LVAD patients but play an integral role in their care. To accomplish that, they need to understand the elements of LVAD function, physiology and clinical use. This article provides a concise overview of the medical management of LVAD patients for nonexpert clinicians. Our presentation includes the basics of LVAD physiology, design, and operation, patient selection and assessment, medical management, adverse event identification and management, multidisciplinary care, and management of special circumstances, such as noncardiac surgery, cardiac arrest, and end-of-life care. The clinical examination of LVAD patients is unique in terms of blood pressure and heart rate assessment, LVAD “hum” auscultation, driveline and insertion site inspection, and device parameter recording. Important potential device-related adverse events include stroke, gastrointestinal bleeding, hematologic disorders, device infection, LVAD dysfunction, arrhythmias, and heart failure. Special considerations include the approach to the unconscious or pulseless patient, noncardiac surgery, and palliative care. An understanding of the principles presented in this paper will enable the nonexpert clinician to be effective in collaborating with an LVAD center in the assessment, medical management, and follow-up of LVAD patients. Future opportunities and challenges include the improvement of device designs, greater application of minimally invasive surgical implantation techniques, and management of health economics in cost-constrained systems like those of Canada and many other jurisdictions.

      Résumé

      Les dispositifs d’assistance ventriculaire gauche (DAVG) permettent d’offrir à certains patients atteints d’une insuffisance cardiaque avancée une assistance circulatoire à court ou à long terme afin d’améliorer la survie et de réduire la morbidité. Les DAVG sont de plus en plus souvent utilisés et sont maintenant indiqués dans un plus grand nombre de cas. Les dispensateurs de soins de santé de différentes spécialités seront donc appelés non seulement à traiter des patients porteurs d’un DAVG, mais aussi à jouer un rôle de premier plan dans les soins qui leur sont prodigués. Pour bien jouer ce rôle, ils doivent comprendre les différents aspects de la fonction, de la physiologie et de l’utilisation clinique des DAVG. Nous présentons donc un aperçu de la prise en charge médicale des patients porteurs d’un DAVG à l’intention des cliniciens non experts. Nous abordons notamment les notions fondamentales de la physiologie, de la conception et du fonctionnement des DAVG, de la sélection et de l’évaluation des patients, de la prise en charge médicale, de la détection et de la prise en charge des événements indésirables, des soins multidisciplinaires et de la prise en charge des cas particuliers, par exemple lorsqu’un patient doit subir une intervention chirurgicale non cardiaque, subit un arrêt cardiaque ou reçoit des soins de fin de vie. L’examen clinique des patients porteurs d’un DAVG présente des particularités à différents égards : mesure de la pression artérielle et de la fréquence cardiaque, auscultation du bruit du DAVG, inspection du câble percutané et du point d’insertion, et consignation des paramètres du dispositif. Les événements indésirables graves pouvant survenir chez un patient porteur d’un DAVG sont l’accident vasculaire cérébral, l’hémorragie gastro-intestinale, les troubles hématologiques, l’infection du dispositif, le mauvais fonctionnement du DAVG, les arythmies et l’insuffisance cardiaque. Parmi les considérations particulières, citons l’approche à adopter en présence d’un patient inconscient ou sans pouls, les interventions chirurgicales non cardiaques et les soins palliatifs. Le clinicien non expert qui comprend bien les principes présentés dans le présent article pourra collaborer efficacement avec un centre spécialisé dans les DAVG pour l’évaluation, la prise en charge médicale et le suivi des patients porteurs d’un DAVG. Les possibilités à exploiter et les défis à relever comprennent l’amélioration de la conception des dispositifs, l’adoption élargie de techniques chirurgicales d’implantation minimalement invasives et la gestion des paramètres de l’économie de la santé dans des systèmes où les budgets sont limités, comme c’est le cas au Canada et dans de nombreux autres pays.

      Overview

      Left ventricular assist devices (LVADs) improve survival and reduce morbidity in selected patients with advanced heart failure.
      • Slaughter M.S.
      • Rogers J.G.
      • Milano C.A.
      • et al.
      Advanced heart failure treated with continuous-flow left ventricular assist device.
      • Miller L.W.
      • Pagani F.D.
      • Russell S.D.
      • et al.
      Use of a continuous-flow device in patients awaiting heart transplantation.
      • Mehra M.R.
      • Uriel N.
      • Naka Y.
      • et al.
      A fully magnetically levitated left ventricular assist device—final report.
      LVADs are increasingly used and have been implanted in more than 16,500 patients worldwide.
      • Goldstein D.J.
      • Meyns B.
      • Xie R.
      • et al.
      Third annual report from the ISHLT mechanically assisted circulatory support registry: a comparison of centrifugal and axial continuous-flow left ventricular assist devices.
      Current-generation continuous-flow devices are associated with 1-year and 2-year survival rates of 80% and 70%, respectively.
      • Kirklin J.K.
      • Pagani F.D.
      • Kormos R.L.
      • et al.
      Eighth annual INTERMACS report: special focus on framing the impact of adverse events.
      Although survival remains lower than with heart transplantation,
      • Goldstein D.J.
      • Meyns B.
      • Xie R.
      • et al.
      Third annual report from the ISHLT mechanically assisted circulatory support registry: a comparison of centrifugal and axial continuous-flow left ventricular assist devices.
      LVADs play an important role as a short-term (bridge) strategy to support a patient with heart failure. Expanded indications for LVADs as a lifelong (destination) strategy were recently approved in some Canadian jurisdictions based on a health economics analysis.
      Health Quality Ontario
      Left ventricular assist devices for destination therapy: OHTAC recommendation. Toronto, 2016.
      ,
      Health Quality Ontario
      Left ventricular assist devices for destination therapy: a health technology assessment. Vol 16, 2016.
      With the increasing prevalence of LVADs, clinicians across many specialties will encounter these patients and must develop comfort in their care. We here present a practical guide to clinicians for the long-term care of LVAD patients.

      LVAD system overview

      Three durable LVADs are approved for use in Canada: Heartmate II (St Jude Medical, St Paul, MN), Heartmate 3 (St Jude Medical), and Heartware HVAD (Heartware, Framingham, MA). The basic components are: 1) an inflow cannula which serves as a conduit for blood from the LV to the pump; 2) a pump with an impeller that delivers continuous blood flow; 3) an outflow graft which serves as a conduit for blood from the pump to the aorta; and 4) a tunnelled driveline that connects the pump to an external controller. Two power cables connect the external controller to a power source (battery or alternating current). The device will still function if only 1 power cable is connected but will alert the patient to connect a second power source. A manufacturer-specific programmer is required to interrogate, troubleshoot, or reprogram the device. Additional peripherals may include a charger, additional batteries, and a backup controller. All external components should be regularly maintained.

      LVAD operating parameters

      There are 4 major operating parameters of an LVAD: pump speed (rpm), power (W), flow (L/min), and pulsatility (pulsatility index or peak-to-trough flow speed; Table 1).
      • DeVore A.D.
      • Patel P.A.
      • Patel C.B.
      Medical management of patients with a left ventricular assist device for the non–left ventricular assist device specialist.
      The pump speed determines the speed of the impeller pump and is the fundamental parameter than can be altered. Power output is modulated and measured by the system controller to achieve the set pump speed. Flow is an estimated value based on the pump speed and power output and can be inaccurate in altered physiologic states. Pulsatility is a measure of temporal power fluctuation and is expressed as pulsatility index by Heartmate devices and as peak-to-trough flow speed by the HVAD.
      Table 1Operating parameters of the 3 durable left ventricular assist devices approved for use in Canada
      ParameterHeartmate IIHeartmate 3HVAD
      Typical speed, rpm8000-10,0005000-60002400-3200
      Flow, L/min4-74-64-6
      Power, W5-84.5-6.53-7
      Pulsatility index5-83.5-5.5N/A
      Peak to troughN/AN/A2-4 L/min/beat
      Reproduced from DeVore et al.
      • DeVore A.D.
      • Patel P.A.
      • Patel C.B.
      Medical management of patients with a left ventricular assist device for the non–left ventricular assist device specialist.
      with permission from Elsevier. Copyright © 2017 Elsevier.

      Device-specific considerations

      There are key differences between the 3 approved durable continuous-flow LVADs. The Heartmate II pump generates axial flow and is larger, necessitating a preperitoneal pocket. The HVAD and Heartmate 3 devices are centrifugal pumps and can be implanted intrapericardially through a less invasive approach owing to their smaller profile. Centrifugal pumps are more sensitive to preload and afterload and therefore require tight blood pressure control. Centrifugal pumps provide automatic pump speed modulation, through proprietary algorithms (ie, Lavare Cycle in the HVAD and Artificial Pulse in the Heartmate 3), which consists of rapid slowing and acceleration of pump speeds. This is intended to enhance washing of the pump and allow for possible aortic valve opening to reduce vascular and thrombotic complications.
      • Saeed D.
      • Westenfeld R.
      • Maxhera B.
      • et al.
      Prevalence of de novo aortic valve insufficiency in patients after Heartware VAD implantation with an intermittent low-speed algorithm.
      ,
      • Mehra M.R.
      • Naka Y.
      • Uriel N.
      • et al.
      A fully magnetically levitated circulatory pump for advanced heart failure.

      LVAD physiology

      The aberrant physiology of continuous-flow LVADs primarily relates to a lack or near lack of pulsatility and explains the nuances of patient care and adverse events. The arterial waveform is a reflection of loading conditions, aortic valve function, and the relative contributions of the LVAD and left ventricle (LV) to circulatory flow. Continuous-flow LVADs continuously move blood from the LV to the aorta, albeit not at a constant rate. LVAD pump flow is affected by loading conditions: Compared with the LV, continuous-flow LVADs are ∼ 3-4 times more sensitive to afterload and 3 times less sensitive to preload.
      • Khalil H.A.
      • Cohn W.E.
      • Metcalfe R.W.
      • Frazier O.H.
      Preload sensitivity of the Jarvik 2000 and Heartmate II left ventricular assist devices.
      • Fukamachi K.
      • Shiose A.
      • Massiello A.
      • et al.
      Preload sensitivity in cardiac assist devices.
      • Lim H.S.
      • Howell N.
      • Ranasinghe A.
      The physiology of continuous-flow left ventricular assist devices.
      The LVAD and LV can be thought of as competing for preload and in their contribution to circulatory flow. This relationship is routinely demonstrated during hemodynamic ramp studies by changing LVAD pump speed. As LVAD pump speed and flow increase, diastolic blood pressure increases while systolic blood pressure remains relatively constant, leading to an overall reduction in pulse pressure.
      • Myers T.J.
      • Bolmers M.
      • Gregoric I.D.
      • Kar B.
      • Frazier O.H.H.
      Assessment of arterial blood pressure during support with an axial flow left ventricular assist device.
      In addition, increased LVAD flows reduce LV volume and preload, resulting in reduced LV contractility and intrinsic stroke volume.
      • Lim H.S.
      • Howell N.
      • Ranasinghe A.
      The physiology of continuous-flow left ventricular assist devices.
      With increasing LVAD support, LV contractility may decrease to the point where LV systolic pressure does not exceed aortic pressure, resulting in an absence of aortic valve opening. Conversely, if LVAD support is reduced, LV preload, pressure, and intrinsic stroke volume will increase while diastolic blood pressure will decrease, resulting in increased pulsatility. LVAD patients may therefore lack pulsatile circulation, which confounds their clinical exam and predisposes them to adverse events. In such patients, measurement of blood pressure by means of an oscillometric or auscultatory blood pressure cuff is problematic. Doppler blood pressure is the preferred method, with the assumption that it represents the mean arterial pressure. The clinician must be mindful that in a patient with pulsatile circulation, the Doppler blood pressure represents systolic blood pressure and is increasingly inaccurate with increasing pulsatility.

      Selection of an LVAD Patient

      There are no universally accepted patient criteria for LVAD implantation.
      • Gustafsson F.
      • Rogers J.G.
      Left ventricular assist device therapy in advanced heart failure: patient selection and outcomes.
      ,
      • Ezekowitz J.A.
      • O’Meara E.
      • McDonald M.A.
      • et al.
      2017 comprehensive update of the canadian cardiovascular society guidelines for the management of heart failure.
      Canadian guidelines recommend consideration for advanced heart failure strategies in patients who, despite optimal treatment, continue to exhibit progressive or persistent New York Heart Association (NYHA) functional class III or IV heart failure symptoms accompanied by at least 1 finding of advanced heart failure (Table 2).
      • Ezekowitz J.A.
      • O’Meara E.
      • McDonald M.A.
      • et al.
      2017 comprehensive update of the canadian cardiovascular society guidelines for the management of heart failure.
      We recommend referral of such patients to a multidisciplinary advanced heart failure clinic to determine the best advanced heart failure strategy, which may include cardiac transplantation, mechanical circulatory support (MCS), or palliative care.
      Table 2Indication for advanced heart failure therapies assessment
      Advanced heart failure despite optimal medical treatment with persistent New York Heart Association functional class III or IV symptoms and at least one of:
      • Left ventricular ejection fraction < 25%
      • Peak exercise oxygen consumption < 14 mL/kg/min (or < 50% predicted)
      • Progressive organ dysfunction due to hypoperfusion, not inadequate filling pressures
      • Recurrent heart failure hospitalizations not due to a clearly reversible cause
      • Diuretic refractoriness associated with worsening renal function
      • Inotropic support required for symptoms or end organ function
      • Worsening right heart failure and post-capillary pulmonary hypertension
      • 6-minute walk test distance < 300 m
      • 1-year mortality > 20%-25% predicted by heart failure risk scores
      • Progressive renal or hepatic dysfunction
      • Persistent hyponatremia (< 134 mEq/L)
      • Cardiac cachexia
      • Inability to perform activities of daily living
      Modified from Ezekowitz et al.
      • Ezekowitz J.A.
      • O’Meara E.
      • McDonald M.A.
      • et al.
      2017 comprehensive update of the canadian cardiovascular society guidelines for the management of heart failure.
      with permission from Elsevier. Copyright © 2017 Elsevier.
      In those who receive an LVAD, the implant strategy is determined by their eligibility for heart transplantation (Fig. 1). Bridging strategies are used for current or potential candidates for transplantation. A bridge-to-transplant (BTT) strategy is used in a patient actively listed for heart transplantation to improve survival, reduce symptoms, and improve organ function while awaiting a suitable donor heart. A bridge-to-candidacy (BTC) strategy provides the opportunity to resolve medical, social, or financial barriers to transplantation in a patient who would otherwise be eligible, and a bridge-to-decision (BTD) strategy provides additional time to assess the transplant candidacy of a patient. A bridge-to-recovery (BTR) strategy allows time for myocardial recovery and subsequent LVAD explantation. Destination therapy (DT) is for patients who are not qualified for heart transplantation but require lifelong circulatory support. DT is now funded in parts of Canada as an up-front strategy for LVAD patients.
      Health Quality Ontario
      Left ventricular assist devices for destination therapy: OHTAC recommendation. Toronto, 2016.
      The specific LVAD strategy may evolve over time with changes in a patient’s clinical status. For example, a BTT-LVAD patient who develops a debilitating stroke may change to a DT strategy. Conversely, a BTT-LVAD patient who achieves myocardial recovery may change to a BTR strategy followed by LVAD explantation.
      Figure thumbnail gr1
      Figure 1Left ventricular assist device implantation strategies are based on recipient transplant eligibility and may evolve based on changes in the patient’s clinical status.

      Assessment of an LVAD Patient

      We describe the basic assessment of an LVAD patient and provide a checklist for future reference in Table 3.
      Table 3Left ventricular assist device (LVAD) patient evaluation checklist
      CategoryAssessment
      HistorySymptom (heart failure, infection, bleeding, stroke, hemolysis)

      Medication adherence, tolerability, and adverse effects

      Quality of life, caregiver stress/burnout
      ExaminationLVAD exam:
      • Doppler blood pressure
      • LVAD “hum”
      • Heart rate (via electrocardiography)
      • Driveline inspection
      • Standard physical exam
      DeviceParameters (pump speed, flow, power, pulsatility, alarms)

      Equipment inspection (damage, connections, battery health)
      InvestigationsBlood work (CBC, chemistries, BNP, INR, LDH)

      Urine analysis

      Electrocardiography

      Chest x-ray

      Pacemaker/ICD interrogation

      Microbiology samples (if infection suspected)

      Advanced imaging (if device complication suspected)
      Medication reviewAntithrombotic therapy:
      • Aspirin
      • Vitamin K antagonist (INR range 2-3)
      Antihypertensives (target Doppler blood pressure ≤ 80 mm Hg)

      Heart failure medications

      Antiarrhythmics
      ComplicationsDevice malfunction

      Heart failure

      Arrhythmia

      Infection

      Bleeding

      Hypertension (blood pressure > 80 mm Hg)
      Follow-up planNotify primary care provider and LVAD team

      Prescriptions, laboratory requisitions, follow-up appointments
      BNP, B-type natriuretic peptide; CBC, complete blood count; ICD, implantable cardioverter-defibrillator; INR, international normalized ratio; LDH, lactate dehydrogenase.

      History and physical assessment

      A focused history relating to the LVAD and its complications should be obtained in all patients with an LVAD, regardless of their presenting issue. The history should include symptoms of heart failure, infection, neurologic events, exercise intolerance, hemolysis (dark urine), bleeding, medication adherence, tolerability, and adverse effects, and device parameters and alarms, if present. Quality of life may be assessed with the use of questionnaires at regular intervals.
      The clinical examination of a patient with an LVAD is unique in the method of blood pressure assessment (ie, sometimes using Doppler ultrasound probe on the brachial artery and a sphygmomanometer), heart rate assessment (by means of electrocardiography or, in HVAD patients, the device waveform), auscultation of the LVAD “hum,” inspection of the driveline and its insertion site, and recording of device parameters.

      Device interrogation

      Device interrogation should include assessment of pump speed, power, flow, and alarms (Table 4). The pulsatility index of Heartmate devices and flow range of HVAD devices should be examined. The LVAD team should be involved for alarm troubleshooting (eg, low flow alarms) and device parameter changes.
      Table 4Assessment and management of left ventricular assist device (LVAD) alarms
      Reproduced from Cook et al.
      • Cook J.L.
      • Colvin M.
      • Francis G.S.
      • et al.
      Recommendations for the use of mechanical circulatory support: ambulatory and community patient care: a scientific statement from the American Heart Association.
      with permission from American Heart Association. ©2017 American Heart Association, Inc.
      Potential causeAdvisory (noncritical)Critical
      PowerPower source disconnect

      Lower battery power

      System controller internal battery depleted
      Driveline disconnect

      Depleted batteries

      Power module disconnect (if not connected to batteries)
      HardwareSystem-controlled dysfunction

      Lead fracture
      Pump stoppage (failure)

      System-controlled malfunction
      Low flowLow flow and/or suction event:
      • Speed too high or low
      • Hypovolemia
      • RV dysfunction
      • Tamponade
      • Hypertension
      • Inflow/outflow obstruction
      • Arrhythmia
      Extremely low flow:
      • Speed too high or low
      • Hypovolemia
      • RV dysfunction
      • Tamponade
      • Hypertension
      • Inflow/outflow obstruction
      • Arrhythmia
      High powerIncreased power:
      • Thrombus
      • Hypertension
      • Electric fault
      EvaluationCall LVAD team

      Assess within 24 hours

      Auscultate device

      Doppler blood pressure

      INR/PT, PTT

      LDH

      ECG

      CT/CXR to assess cannula/device positioning

      Inspect power cable connections
      Call LVAD team

      Immediate evaluation

      Auscultate device

      Doppler blood pressure

      INR/PT, PTT

      LDH

      ECG

      Inspect driveline and power cable connections

      Pulmonary artery catheterization
      Management optionsReplace batteries or connect to power module

      Intravenous fluids

      Inotropes

      Exchange system controller

      Hypertension control

      Anticoagulation/thrombolysis
      Replace batteries or connect to power module

      Exchange system controller

      ACLS (when appropriate)

      Treatment for cardiogenic shock
      ACLS, advanced cardiac life support; CT, computed tomography (CT); CXR, chest x-ray; LV, left ventricle; RV, right ventricle; INR, international normalized ratio; PT, partial thromboplastin; PT, partial thromboplastin time; LDH, lactate dehydrogenase; ECG, electrocardiography.

      Laboratory and imaging testing

      Routine laboratory assessment includes hematology and electrolyte profiles, renal function, coagulation parameters, liver enzymes, and B-type natriuretic peptide. Screening for hemolysis is performed with the use of plasma-free hemoglobin or lactate dehydrogenase (LDH). An LDH level significantly above the patient’s baseline or 2.5 times the upper limit of normal should raise suspicion of hemolysis and prompt consultation with an LVAD center.
      • Cowger J.A.
      • Romano M.A.
      • Shah P.
      • et al.
      Hemolysis: a harbinger of adverse outcome after left ventricular assist device implant.
      Electrocardiography should be used to determine the rhythm at each clinic visit if there are concerns of arrhythmia. Cardiopulmonary exercise testing can be used to evaluate functional capacity. Chest radiography is used to evaluate the pump position and proximal driveline with the use of modified anterior-posterior and lateral views. Transthoracic echocardiography can be used to assess ventricular function, ventricular unloading, valvular function (eg, aortic valve opening), and the inflow and outflow. Guidelines for the use of echocardiography in the assessment of LVAD patients are available from the American Society of Echocardiography.
      • Stainback R.F.
      • Estep J.D.
      • Agler D.A.
      • et al.
      Echocardiography in the management of patients with left ventricular assist devices: recommendations from the American Society of Echocardiography.
      Contrast-enhanced gated computed tomographic (CT) scans can be used to assess LVAD components outside of the metallic pump enclosure, such as outflow cannula positioning and patency.
      • Vivo R.P.
      • Kassi M.
      • Estep J.D.
      • et al.
      MDCT Assessment of mechanical circulatory support device complications.
      If infection is suspected, microbiologic samples may be obtained from the driveline site, urine, sputum, and blood. Additional imaging with the use of ultrasonography, transesophageal echocardiography, CT, or nuclear imaging is useful in selected cases to identify the source of infections.

      Outpatient Care of an LVAD Patient

      Antithrombotic therapy

      Antithrombotic therapy is necessary to prevent thrombotic complications of an LVAD and must be balanced against the bleeding risk of the patient. Aspirin is used daily in combination with warfarin to maintain the international normalized ratio (INR) within a device-specific range (usually 2.0-3.0 for the devices being discussed here).
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      Direct oral anticoagulants have not been adequately studied in this population and should not be used.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      ,
      • Potapov E.V.
      • Antonides C.
      • Crespo-Leiro M.G.
      • et al.
      2019 EACTS expert consensus on long-term mechanical circulatory support.

      Medical therapy

      Heart failure medications may be started on most LVAD patients. Diuretics are useful to manage volume overload. Antiarrhythmics can reduce the burden of atrial and ventricular arrhythmias. Neurohormonal therapy with beta-blockers, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, and mineralocorticoid receptor antagonists should be considered.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      ,
      • Potapov E.V.
      • Antonides C.
      • Crespo-Leiro M.G.
      • et al.
      2019 EACTS expert consensus on long-term mechanical circulatory support.
      However, the efficacy of these evidence-based heart failure therapies as BTR is unknown.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.

      Risk factor modification

      Blood pressure control is necessary to maximize LVAD output and ensure adequate LV decompression. Preexisting hypertension may return after a patient’s heart failure improves with an LVAD. This is problematic, because continuous-flow LVADs are afterload dependent such that for a given pump speed the LVAD output is reduced with higher blood pressures. Blood pressure control is also associated with a reduced risk of stroke in HVAD patients.
      • Milano C.A.
      • Rogers J.G.
      • Tatooles A.J.
      • et al.
      HVAD: the ENDURANCE Supplemental Trial.
      International guidelines recommended a target Doppler mean blood pressure of ≤ 80 mm Hg in LVAD patients.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      We recommend intensive modification of standard cardiovascular risk factors, which is outlined elsewhere.
      • Arnett D.K.
      • Blumenthal R.S.
      • Albert M.A.
      • et al.
      2019 ACC/AHA guideline on the primary prevention of cardiovascular disease.
      This is particularly important for BTT-LVAD patients, because uncontrolled cardiovascular risk factors, such as morbid obesity and diabetes with end-organ damage, may contraindicate transplantation.
      • Mehra M.R.
      • Canter C.E.
      • Hannan M.M.
      • et al.
      The 2016 International Society for Heart Lung Transplantation listing criteria for heart transplantation: a 10-year update.

      Cardiac rehabilitation

      Cardiac rehabilitation in LVAD patients is both safe and effective in improving quality of life and functional ability.
      • Karapolat H.
      • Engin C.
      • Eroglu M.
      • et al.
      Efficacy of the cardiac rehabilitation program in patients with end-stage heart failure, heart transplant patients, and left ventricular assist device recipients.
      ,
      • Dugmore L.D.
      • Tipson R.J.
      • Phillips M.H.
      • et al.
      Changes in cardiorespiratory fitness, psychological wellbeing, quality of life, and vocational status following a 12 month cardiac exercise rehabilitation programme.
      All capable patients should be enrolled in cardiac rehabilitation after LVAD implantation.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.

      Adverse Events

      Major adverse effects continue to limit the long-term success of durable LVADs. At 1 year, ∼ 56% of patients with LVADs are “living well,” defined as freedom from death, stroke, bleeding requiring reoperation, pump exchange, RV mechanical support, and device-related infection. The following complications should be considered during any LVAD patient encounter, and should always be managed in close collaboration with the LVAD team.

      Ischemic and hemorrhagic strokes

      Stroke is the major cause of death between 6 and 24 months after LVAD implantation and occurs at a rate of 8.7% per year.
      • Kirklin J.K.
      • Pagani F.D.
      • Kormos R.L.
      • et al.
      Eighth annual INTERMACS report: special focus on framing the impact of adverse events.
      ,
      • Parikh N.S.
      • Cool J.
      • Karas M.G.
      • Boehme A.K.
      • Kamel H.
      Stroke risk and mortality in patients with ventricular assist devices.
      Ischemic strokes may result from embolic sources on the aortic valve, pump, inflow cannula, and outflow graft.
      • Willey J.Z.
      • Demmer R.T.
      • Takayama H.
      • Colombo P.C.
      • Lazar R.M.
      Cerebrovascular disease in the era of left ventricular assist devices with continuous flow: risk factors, diagnosis, and treatment.
      Hemorrhagic strokes may occur secondary to coagulopathy, hypertension, endocarditis, or hemorrhagic conversion of ischemic strokes.
      • Willey J.Z.
      • Demmer R.T.
      • Takayama H.
      • Colombo P.C.
      • Lazar R.M.
      Cerebrovascular disease in the era of left ventricular assist devices with continuous flow: risk factors, diagnosis, and treatment.
      The centrifugal HVAD device showed equivalent stroke rates compared with the axial Heartmate II as long as blood pressure is controlled.
      • Milano C.A.
      • Rogers J.G.
      • Tatooles A.J.
      • et al.
      HVAD: the ENDURANCE Supplemental Trial.
      The newer Heartmate 3 resulted in a lower stroke rate (9.9% vs 19.4% at 2 years) compared with the Heartmate II.
      • Mehra M.R.
      • Uriel N.
      • Naka Y.
      • et al.
      A fully magnetically levitated left ventricular assist device—final report.

      Gastrointestinal bleeding

      Gastrointestinal bleeding is a common and potentially severe adverse event in LVAD patients and occurs with a frequency of 0.31-0.56 events per patient-year.
      • Mehra M.R.
      • Uriel N.
      • Naka Y.
      • et al.
      A fully magnetically levitated left ventricular assist device—final report.
      ,
      • Rogers J.G.
      • Pagani F.D.
      • Tatooles A.J.
      • et al.
      Intrapericardial left ventricular assist device for advanced heart failure.
      Causes of bleeding include 1) antithrombotic therapy, 2) acquired coagulopathy, and 3) the development of angiodysplasia, which may be related to elevated levels of circulating angiogenic mediators.
      • Tabit C.E.
      • Chen P.
      • Kim G.H.
      • et al.
      Elevated angiopoietin-2 level in patients with continuous-flow left ventricular assist devices leads to altered angiogenesis and is associated with higher nonsurgical bleeding.
      LVAD design may affect gastrointestinal bleeding risk. There was no difference in gastrointestinal bleeding between the HVAD and the Heartmate II,
      • Rogers J.G.
      • Pagani F.D.
      • Tatooles A.J.
      • et al.
      Intrapericardial left ventricular assist device for advanced heart failure.
      whereas the Heartmate 3 resulted in a lower incidence of gastrointestinal bleeding (24.5% vs 30.9% at 2 years) compared with the Heartmate II.
      Most clinically significant gastrointestinal bleeding can be managed conservatively in consultation with gastroenterology.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      Endoscopic evaluation is recommended for first and repeated episodes of gastrointestinal bleeding.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      In cases where a source is not identified, investigation of the small bowel may be considered.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      The LVAD team should be contacted, if possible, before withholding or reversing antithrombotic therapy.

      Hematologic disorders

      Continuous-flow LVADs result in blood flow rheology that induces a number of hematologic effects due to shear stress.
      • Wilson S.R.
      • Givertz M.M.
      • Stewart G.C.
      • Mudge G.H.
      Ventricular assist devices. the challenges of outpatient management.
      This results in a low-grade hemolysis and an acquired coagulopathy related to acquired von Willebrand syndrome, platelet dysfunction, and fibrinolysis.
      • Wilson S.R.
      • Givertz M.M.
      • Stewart G.C.
      • Mudge G.H.
      Ventricular assist devices. the challenges of outpatient management.
      Acquired von Willebrand syndrome is the main bleeding risk factor in LVAD patients. Von Willebrand factor (VWF) circulates in the blood as the largest soluble protein and exists as a high-molecular-weight multimer of identical subunits.
      • Sadler J.E.
      Biochemistry and genetics of von Willebrand factor.
      Shear stress causes proteolysis and a measurable reduction of VWF multimers, resulting in acquired von Willebrand syndrome and platelet dysfunction.
      • Kormos R.F.
      • Wieselthaler G.M.
      • Salerno C.
      • Shumway S.J.
      • Pagani F.D.
      Acquired von Willebrand syndrome in continuous-flow ventricular assist device recipients.
      • Meyer A.L.
      • Malehsa D.
      • Bara C.
      • et al.
      Acquired von Willebrand syndrome in patients with an axial flow left ventricular assist device.
      • Klovaite J.
      • Gustafsson F.
      • Mortensen S.A.
      • Sander K.
      • Nielsen L.B.
      Severely impaired von Willebrand factor–dependent platelet aggregation in patients with a continuous-flow left ventricular assist device (Heartmate II).
      The magnitude of VWF reduction is typically modulated by pulsatility, which is a trigger for compensatory endothelial release of VWF and absent in most LVAD patients.
      • Vincent F.
      • Rauch A.
      • Loobuyck V.
      • et al.
      Arterial pulsatility and circulating von Willebrand factor in patients on mechanical circulatory support.
      The resultant bleeding syndrome is similar to Heyde syndrome in aortic stenosis, which also involves shear stress, low pulse pressure, angiodysplasia, and bleeding.
      • Sadler J.E.
      Aortic stenosis, von Willebrand factor, and bleeding.
      There is near immediate and complete recovery of acquired von Willebrand syndrome after LVAD explantation.
      • Davis M.E.
      • Haglund N.A.
      • Tricarico N.M.
      • Matafonov A.
      • Gailani D.
      • Maltais S.
      Immediate recovery of acquired von willebrand syndrome after left ventricular assist device explantation: implications for heart transplantation.
      Increased fibrinolysis and endothelial dysfunction are present in LVAD patients at baseline due to longstanding heart failure.
      • John R.
      • Panch S.
      • Hrabe J.
      • et al.
      Activation of endothelial and coagulation systems in left ventricular assist device recipients.
      ,
      • Slaughter M.S.
      • Sobieski M.A.
      • Gallagher C.
      • et al.
      Fibrinolytic activation during long-term support with the Heartmate II left ventricular assist device.
      Fibrinolytic responses initially increase after LVAD implantation and then gradually normalize by 12 months.
      • Slaughter M.S.
      • Sobieski M.A.
      • Gallagher C.
      • et al.
      Fibrinolytic activation during long-term support with the Heartmate II left ventricular assist device.
      The bleeding risk associated with LVAD-related acquired von Willebrand syndrome, platelet dysfunction, and fibrinolysis is compounded by required antithrombotic therapy using antiplatelets and vitamin K antagonists.

      LVAD malfunction

      LVADs may develop electrical and mechanical malfunctions. Electrical malfunction typically presents with alarms and should be managed by stabilizing the patient, ensuring device connections, and reviewing the alarms. Mechanical malfunction may be intrinsic or extrinsic to the LVAD and can present with hemolysis, heart failure, or abnormal LVAD parameters. Intrinsic mechanical pump failure is rare. Extrinsic mechanical pump malfunction typically results from LVAD thrombosis.
      LVAD thrombosis may occur on the inflow cannula, pump, or outflow graft. The presentation of LVAD thrombosis varies from asymptomatic hemolysis, to changes in pump parameters (ie, power or flow), to biventricular failure and cardiogenic shock. Suspected LVAD thrombosis should be quickly investigated by means of biochemical and imaging studies. Treatment varies from adjusting antithrombotic therapy to thrombolysis or emergent surgical pump replacement. The LVAD team should be involved in all cases of suspected pump thrombosis.
      There are device-specific differences in rates of LVAD thrombosis. Whereas the HVAD showed no difference in pump thrombosis compared with the Heartmate II,
      • Rogers J.G.
      • Pagani F.D.
      • Tatooles A.J.
      • et al.
      Intrapericardial left ventricular assist device for advanced heart failure.
      the Heartmate 3 was associated with a lower rate of suspected or confirmed pump thrombosis (1.4% vs 13.9% at 2 years) compared with the Heartmate II.
      • Mehra M.R.
      • Uriel N.
      • Naka Y.
      • et al.
      A fully magnetically levitated left ventricular assist device—final report.
      The Heartmate 3 uses an “artificial pulse” by changing the rotor speed every 2 seconds to reduce zones of recirculation and stasis.

      Thoratec Corp. Heartmate 3 left ventricular assist system instructions for use. Pleasanton, CA, USA: 2017.

      Device infections

      Infection is the second-most frequent adverse event (after bleeding) in the first 3 months after implantation and the most frequent adverse event thereafter.
      • Kirklin J.K.
      • Pagani F.D.
      • Kormos R.L.
      • et al.
      Eighth annual INTERMACS report: special focus on framing the impact of adverse events.
      Driveline infections are the most common (85%) and are frequently associated with invasive infections.
      • Gordon R.J.
      • Weinberg A.D.
      • Pagani F.D.
      • et al.
      Prospective, multicenter study of ventricular assist device infections.
      LVAD patients are educated on strategies to minimize risk of infection, including minimizing driveline movement and trauma, regular dressing changes, and driveline site surveillance.
      The evaluation of an LVAD infection includes driveline cultures, blood cultures, and imaging with the use of ultrasound or CT. The most common pathogens are skin organisms. International guidelines for the management of infections in LVAD patient are available.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.

      Arrhythmia

      Atrial and ventricular arrhythmias are commonly observed in LVAD patients, and their impact on outcomes is not well defined. Ventricular arrhythmias generally require antiarrhythmic or antitachycardia therapies. Canadian and American guidelines suggest consideration of implantable cardioverter-defibrillator (ICD) implantation in LVAD patients, but noting the lack of evidence to support a mortality benefit.
      • Gopinathannair R.
      • Cornwell W.K.
      • Dukes J.W.
      • et al.
      Device therapy and arrhythmia management in left ventricular assist device recipients: a scientific statement from the American Heart Association.
      ,
      • Bennett M.
      • Parkash R.
      • Nery P.
      • et al.
      Canadian Cardiovascular Society/Canadian Heart Rhythm Society 2016 implantable cardioverter-defibrillator guidelines.
      If an ICD is implanted, a conservative programming strategy is recommended to minimize ICD shocks, given that sustained ventricular arrhythmias are often well tolerated in LVAD patients.
      • Gopinathannair R.
      • Cornwell W.K.
      • Dukes J.W.
      • et al.
      Device therapy and arrhythmia management in left ventricular assist device recipients: a scientific statement from the American Heart Association.

      Heart failure

      Heart failure in LVAD patients often results from RV-LVAD interactions and is associated with worse outcomes.
      • Argiriou M.
      • Kolokotron S.
      • Sakellaridis T.
      • et al.
      Right heart failure post left ventricular assist device implantation Mihalis.
      • Kormos R.L.
      • Teuteberg J.J.
      • Pagani F.D.
      • et al.
      Right ventricular failure in patients with the Heartmate II continuous-flow left ventricular assist device: incidence, risk factors, and effect on outcomes.
      • Takeda K.
      • Takayama H.
      • Colombo P.C.
      • et al.
      Incidence and clinical significance of late right heart failure during continuous-flow left ventricular assist device support.
      • Rich J.D.
      • Gosev I.
      • Patel C.B.
      • et al.
      The incidence, risk factors, and outcomes associated with late right-sided heart failure in patients supported with an axial-flow left ventricular assist device.
      • Kapelios C.J.
      • Charitos C.
      • Kaldara E.
      • et al.
      Late-onset right ventricular dysfunction after mechanical support by a continuous-flow left ventricular assist device.
      • Dang N.C.
      • Topkara V.K.
      • Mercando M.
      • et al.
      Right heart failure after left ventricular assist device implantation in patients with chronic congestive heart failure.
      • Baumwol J.
      • MacDonald P.S.
      • Keogh A.M.
      • et al.
      Right heart failure and “failure to thrive” after left ventricular assist device: clinical predictors and outcomes.
      Before LVAD implantation, LV failure limits RV preload and increases RV afterload. LVADs improve RV function by decompressing the LV, which in turn leads to a reduction of pulmonary vascular resistance. However, the LVAD may also impose deleterious effects on the RV. RV volume loading may unmask occult RV failure, increase tricuspid annular dilation, and worsen tricuspid regurgitation. LV decompression leads to a leftward shift of the interventricular septum, which may decrease septal contribution to RV contraction and impair myocardial mechanics.
      • Moon M.R.
      • Bolger A.F.
      • DeAnda A.
      • et al.
      Septal function during left ventricular unloading.
      ,
      • Farrar D.J.
      • Compton P.G.
      • Hershon J.J.
      • Fonger J.D.
      • Hill J.D.
      Right heart interaction with the mechanically assisted left heart.
      RV failure may be exacerbated by atrial and ventricular arrhythmias, which are common after LVAD implantation.
      • Brisco M.A.
      • Sundareswaran K.S.
      • Milano C.A.
      • et al.
      The incidence, risk, and consequences of atrial arrhythmias in patients with continuous-flow left ventricular assist devices.
      ,
      • Cantillon D.J.
      • Saliba W.I.
      • Wazni O.M.
      • et al.
      Low cardiac output associated with ventricular tachyarrhythmias in continuous-flow LVAD recipients with a concomitant ICD (LoCo VT study).
      Heart failure may result also from aortic regurgitation, which commonly results from commissural fusion or trauma.
      • Wang T.S.
      • Hernandez A.F.
      • Felker G.M.
      • et al.
      Valvular heart disease in patients supported with left ventricular assist devices.
      ,
      • Rajagopal K.
      • Daneshmand M.A.
      • Patel C.B.
      • et al.
      Natural history and clinical effect of aortic valve regurgitation after left ventricular assist device implantation.
      The regurgitant fraction is disproportionately high relative to the valvular defect because regurgitation is continuous throughout the cardiac cycle.
      Decompensated heart failure in an LVAD patient should be approached by the predominant phenotype. Isolated left-side heart failure should prompt the clinician to exclude pump malfunction or valvular regurgitation, treat hypertension if present, consider augmenting cardiac output with inotropes or increasing LVAD pump speed, and consider diuresis. Biventricular heart failure should prompt the same considerations with a greater emphasis on diuresis. Isolated right-side heart failure requires a careful assessment of RV function and hemodynamics, often with the use of echocardiography, with consideration for diuresis, inotropes, vasodilators, additional MCS, and palliative care.

      The LVAD Team

      The LVAD patient and their support person(s) have the most important role in the LVAD team. They require engagement, education, and support from the LVAD team to have the resources and capacity to manage the complexities of LVAD care. The LVAD team consists of specialized medical, surgical, and allied health professionals. Physician specialists include cardiac surgeons and cardiologists with expertise in advanced heart failure along with ancillary subspecialties such as psychiatry, palliative care, and others as required. Allied health specialists include nurses, social workers, psychologists, pharmacists, dieticians, physical therapists, occupational therapists, and rehabilitation services. The LVAD coordinator oversees all aspects of LVAD patient care and commonly acts as the central liaison person. LVAD patients can provide the contact information of their LVAD program or coordinator to a requesting physician. They may also have access to 24/7 LVAD support telephone lines, which may be useful to a consulting clinician.

      Transitions Between Hospital and Home

      Before discharge, LVAD patients and their support person(s) require training in LVAD care. This includes the daily management of LVADs, alarm management, battery changes, system controller changes, and an understanding of when to seek medical attention. Pharmacy-led teaching on the proper use of medications, particularly antithrombotic therapy, is imperative. Postoperative and cardiovascular rehabilitation should be completed as either inpatient or outpatient, depending on local resources. When ready, the LVAD patient may transfer to the local outpatient setting for 6-12 weeks (depending on program requirements) before returning to their home locale.
      LVAD patients often report an improvement in symptoms of heart failure shortly after surgery, whereas symptoms of chronic illness, such as deconditioning and malnourishment, take longer to resolve. Early and intensive cardiac rehabilitation is recommended.
      • Slaughter M.S.
      Long-term continuous flow left ventricular assist device support and end-organ function: prospects for destination therapy.
      ,
      • Grady K.L.
      • Magasi S.
      • Hahn E.A.
      • et al.
      Health-related quality of life in mechanical circulatory support: Development of a new conceptual model and items for self-administration.
      LVAD patients can gradually return to most of their activities of living. Some activities are possible with modification, whereas others are prohibited. For example, showering is possible with the use of accessories to protect the device, whereas activities that involve submerging the device, such as taking a bath or swimming, are prohibited. The physical demands of returning to work, strenuous exercise, and sexual intimacy may also be prohibitive.
      • Grady K.L.
      • Magasi S.
      • Hahn E.A.
      • et al.
      Health-related quality of life in mechanical circulatory support: Development of a new conceptual model and items for self-administration.
      ,
      • Casida J.M.
      • Marcuccilli L.
      • Peters R.M.
      • Wright S.
      Lifestyle adjustments of adults with long-term implantable left ventricular assist devices: a phenomenologic inquiry.
      We work with LVAD patients to enable activities of special significance. For example, driving may promote independence, enable social interactions, and reduce caregiver burnout. The ability to drive is patient specific and dependent on local laws. Canadian recommendations permit private driving for continuous-flow LVAD patients with NYHA functional class I-III symptoms who remain stable 2 months after LVAD implantation, whereas commercial driving is prohibited for all LVAD patients.
      • Baskett R.
      • Crowell R.
      • Freed D.
      • Giannetti N.
      • Simpson C.S.
      Canadian Cardiovascular Society focused position statement update on assessment of the cardiac patient for fitness to drive: fitness following left ventricular assist device implantation.
      Return to daily activities such as these offers a sense of normalcy to patients and contributes to an improved quality of life.
      • Wilson S.R.
      • Givertz M.M.
      • Stewart G.C.
      • Mudge G.H.
      Ventricular assist devices. the challenges of outpatient management.
      Transitions to hospital may occur for LVAD-related or non–LVAD-related issues on either elective or nonelective bases. Regardless of the indication for hospitalization, we recommend a systematic approach to the evaluation of an LVAD patient and early notification of the LVAD team (Table 3).

      Special Considerations

      Unconsciousness or cardiac arrest

      In an unconscious LVAD patient, it can be difficult to determine if altered mental status is due to hypoperfusion or a neurologic event such as stroke.
      A conscious LVAD patient typically has no palpable pulse because the device provides continuous nonpulsatile systemic flow. Vital signs such as noninvasive blood pressure and oxygen saturation may be hard to obtain, and heart sounds will be replaced by an LVAD “hum.” Although standard advanced cardiac life support algorithms rely on the presence or absence of a pulse to guide therapy, the lack of a pulse in LVAD patients is common and cannot be used to infer that the patient is in a low-perfusion state or cardiac arrest.
      There is debate as to whether cardiopulmonary resuscitation (CPR) is safe and effective in LVAD patients. Although manufacturers have warned against external compressions owing to the risk of damage to the outflow graft or inflow cannula,

      Thoratec Corp. Heartmate 3 left ventricular assist system instructions for use. Pleasanton, CA, USA: 2017.

      CPR has been safely administered to LVAD patients.
      • Shinar Z.
      • Bellezzo J.
      • Stahovich M.
      • et al.
      Chest compressions may be safe in arresting patients with left ventricular assist devices (LVADs).
      A number of protocols for approaching the unresponsive LVAD patient have been published.
      • Peberdy M.A.
      • Gluck J.A.
      • Ornato J.P.
      • et al.
      Cardiopulmonary resuscitation in adults and children with mechanical circulatory support: a scientific statement from the American Heart Association.
      ,
      • Guglin M.
      Approach to unresponsive patient with LVAD.
      If an unconscious LVAD patient is encountered by trained health personnel, we agree with recommendations for a rapid assessment of signs of life and LVAD functioning before initiating chest compressions (Fig. 2).
      • Peberdy M.A.
      • Gluck J.A.
      • Ornato J.P.
      • et al.
      Cardiopulmonary resuscitation in adults and children with mechanical circulatory support: a scientific statement from the American Heart Association.
      This includes signs of peripheral perfusion (skin colour, temperature, capillary refill), Doppler blood pressure, and (if intubated) partial pressure of end-tidal carbon dioxide. LVAD function should be assessed by listening for an LVAD “hum” and identifying any alarms. If the LVAD is not functioning, the driveline, power source, and system controller should be troubleshot. If LVAD function is not restored, CPR is recommended and the LVAD team should be immediately notified.
      Figure thumbnail gr2
      Figure 2Algorithm for the management of an unresponsive left ventricular assist device (LVAD) patient. ACLS, advanced cardiac life support; EMS, emergency medical services. *Doppler blood pressure, skin temperature and colour, capillary refill, auscultation of LVAD hum, and identification of LVAD alarms may be assessed. End-tidal CO2 > 20 mm Hg or blood pressure via Doppler or arterial line, if available, to be used as signs of adequate circulation. Modified from Peberdy et al.
      • Peberdy M.A.
      • Gluck J.A.
      • Ornato J.P.
      • et al.
      Cardiopulmonary resuscitation in adults and children with mechanical circulatory support: a scientific statement from the American Heart Association.
      with permission from American Heart Association.
      If an unconscious LVAD patient without any signs of life is encountered by an untrained bystander, CPR should be immediately performed.
      • Peberdy M.A.
      • Gluck J.A.
      • Ornato J.P.
      • et al.
      Cardiopulmonary resuscitation in adults and children with mechanical circulatory support: a scientific statement from the American Heart Association.
      The LVAD team should also be immediately notified and the patient should be transferred to an LVAD center if possible.

      Noncardiac surgery

      Noncardiac surgery in an LVAD patient should be planned in collaboration with the LVAD team. Perioperative planning may include bridging anticoagulation, infection prophylaxis, device programming and monitoring, defibrillator reprogramming, and consultation with cardiac surgery and cardiac anaesthesia.
      LVAD parameters should be continuously monitored by trained personnel, such as an LVAD nurse or perfusionist.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      Blood pressure monitoring by means of Doppler is appropriate during minor procedures, but during procedures with a risk of hemodynamic instability, an arterial line should be placed and a central venous catheter considered.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      If the procedure is in close proximity to components of the LVAD, a cardiac surgeon should be immediately available.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.
      A cardiac anaesthetist may be required during procedures with hemodynamic instability owing to the unique considerations of preload, afterload, and vasodilation in LVAD patients.
      Bleeding is the most common surgical complication in LVAD patients. Blood transfusions are associated with poorer outcomes and may result in allosensitization of the patient. Hemodynamically significant fluid shifts may affect LVAD preload and afterload, and consequently function. Surgical infections must be prevented given the potentially devastating consequence of an LVAD device infection. Antibiotic prophylaxis for prevention of endocarditis has not been well studied in the LVAD population but may be considered.
      • Feldman D.
      • Pamboukian S.V.
      • Teuteberg J.J.
      • et al.
      The 2013 International Society for Heart and Lung Transplantation guidelines for mechanical circulatory support: executive summary.

      Outcomes

      Limited data suggest that noncardiac surgery is safe in selected LVAD patients.
      • Davis J.
      • Sanford D.
      • Schilling J.
      • Hardi A.
      • Colditz G.
      Systematic review of outcomes after noncardiac surgery in patients with implanted left ventricular assist devices.
      Importantly, in BTT-LVAD patients, there was no association between elective surgical interventions and a reduced likelihood of heart transplantation.
      • Stehlik J.
      • Nelson D.M.
      • Kfoury A.G.
      • et al.
      Outcome of noncardiac surgery in patients with ventricular assist devices.
      Despite the added complexity, the perioperative risk of an LVAD patient may not preclude necessarily surgical interventions.

      Palliative care

      Palliative care is recommended for all patients with advanced heart failure with the aims to optimize symptoms, enhance quality of life, and provide support to patients and their caregivers.
      • Fang J.C.
      • Ewald G.A.
      • Allen L.A.
      • et al.
      Advanced (stage D) heart failure: a statement from the heart failure society of america guidelines committee.
      An understanding of the patient’s values and preferences is necessary to determine whether an LVAD will help to achieve their goals. The patient and support person(s) must be willing to adapt to life with an LVAD, be capable of LVAD care, and accept the associated risks. Adverse effects, such as stroke, may impair capacity and require additional caregiver support. Comprehensive patient education is necessary to make an informed decision and may result in improved patient decision quality and fewer LVAD implantations.
      • Allen L.A.
      • McIlvennan C.K.
      • Thompson J.S.
      • et al.
      Effectiveness of an intervention supporting shared decision making for destination therapy left ventricular assist device the DECIDE-LVAD randomized clinical trial.
      In patients who proceed to LVAD implantation, we recommend integration of palliative care with their LVAD care. A preparedness plan is recommended, which includes clear health and quality of life goals, advanced directives for LVAD-specific issues, a designated substitute decision maker, and an end-of-life plan.
      As patients approach the end of life, a medically, legally, and ethically permissible decision may be made by a competent patient to withdraw MCS or receive medical assistance in dying (MAID). These scenarios require patient-centered planning and involvement of the LVAD team. Some clinicians conflate LVAD deactivation with assistance in dying owing to the rapidity of death.
      • McIlvennan C.K.
      • Wordingham S.E.
      • Allen L.A.
      • et al.
      Deactivation of left ventricular assist devices: differing perspectives of cardiology and hospice/palliative medicine clinicians.
      The cause of death after LVAD deactivation is the underlying heart failure syndrome. From an ethical standpoint, LVAD deactivation is no different than separation from a ventilator, deactivation of an ICD, or withdrawal of pacemaker support. LVAD deactivation should be performed by experienced personnel who can deactivate the device without triggering alarms. Symptoms of a decreased cardiac output should be preempted with palliative medications before device deactivation, because decreased circulation may delay the effect of medications.
      MAID is permissible in Canada and now accounts for ∼ 1.12% of deaths. The presence of an LVAD does not preclude a patient from MAID.

      Future Directions and Challenges

      LVAD technology development is progressing toward the ultimate goal of not only obviating the need for heart transplantation, but becoming a widely used treatment for an expanding number of patients with advanced heart failure. Work is underway to miniaturize LVADs,
      Medtronic Cardiac Rhythm and Heart Failure
      A clinical trial to evaluate the Heartware MVAD system (MVAdvantage).
      enhance biocompatibility to allow lower-intensity anticoagulation,
      • Netuka I.
      • Ivák P.
      • Tučanová Z.
      • et al.
      Evaluation of low-intensity anticoagulation with a fully magnetically levitated centrifugal-flow circulatory pump—the MAGENTUM 1 study.
      and develop less invasive surgical approaches.
      • McGee E.
      • Danter M.
      • Strueber M.
      • et al.
      Evaluation of a lateral thoracotomy implant approach for a centrifugal-flow left ventricular assist device: the LATERAL clinical trial.
      A fully implantable LVAD without the need for a driveline would dramatically reduce device infection and improve quality of life. Combined use of an implantable hemodynamic monitoring device (CardioMEMS; Abbott Laboratories, Chicago, IL) to optimize LVAD performance has been described and is being studied.
      • Veenis J.F.
      • Manintveld O.C.
      • Constantinescu A.A.
      • et al.
      Design and rationale of haemodynamic guidance with CardioMEMS in patients with a left ventricular assist device: the HEMO-VAD pilot study.
      ,
      • Feldman D.S.
      • Moazami N.
      • Adamson P.B.
      • et al.
      The utility of a wireless implantable hemodynamic monitoring system in patients requiring mechanical circulatory support.
      Future implementations may include closed-loop feedback systems using real-time hemodynamic data to allow for automatic modulation of LVAD parameters.
      As LVAD technology improves, Canadian health care infrastructure must develop in a hub-and-spoke model to identify potential LVAD candidates and care for an expanding number of LVAD recipients. The cost of the device, surgery, and postsurgical complications would have to be significantly reduced to reach the traditionally held upper threshold of $100,000 incremental cost-effectiveness ratio per quality-adjusted life-year.
      Health Quality Ontario
      Left ventricular assist devices for destination therapy: a health technology assessment. Vol 16, 2016.

      Conclusion

      LVADs are increasingly used to improve survival and reduce morbidity in selected patients with advanced heart failure. Clinicians will increasingly encounter patients with LVADs and should become familiar with their care. We have provided a practical overview of LVAD patient care to assist during those patient encounters.

      Disclosures

      The authors have no conflicts of interest to disclose.

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