Abstract
Background
Implantable cardioverter defibrillators (ICDs) have shown benefit in reducing mortality
in patients with heart failure, after myocardial infarction, and those with reduced
ejection fraction. We sought to explore the use of this therapy in specialized heart
function clinics, in rural and urban locations.
Methods
This was a retrospective cohort study performed in 3 specialized heart function clinics
in Nova Scotia, 2 of which were in rural locations. All patients with an initial left
ventricular ejection fraction ≤ 35% were included from 2006 to 2011. Rates of referral,
ICD implantation, and mortality were compared between urban and rural groups.
Results
There were 922 patients included in the study; 636 patients in the urban clinic, 286
in the rural locations. Referral rates were higher in the urban clinic compared with
the rural locations (80.4% vs 68.3%; P = 0.024). Refusal rates for referral were higher in the rural locations (13.7% vs
2.1%; P < 0.0001). Higher referral rates were associated with urban location (odds ratio
[OR], 1.81; 95% confidence interval [CI], 1.01-3.26; P = 0.047), and younger age (OR, 0.96; 95% CI, 0.93-0.99; P = 0.003); lower referral rates for women was observed (OR, 2.29; 95% CI, 1.13-4.63;
P = 0.021). Mortality was significantly associated with older age, lack of referral,
presence of comorbidities (renal failure, diabetes, peripheral vascular disease) and
a rural location.
Conclusions
Specialized heart function clinics have a high rate of appropriate referral for primary
prevention ICDs, but referral rates for this life-saving therapy remain lower in rural
jurisdictions. This disparity in access to care is associated with increased mortality
and might require particular attention to prevent unnecessary deaths.
Résumé
Introduction
Les défibrillateurs cardioverteurs implantables (DCI) ont démontré des avantages dans
la réduction de la mortalité chez les patients souffrant d’insuffisance cardiaque,
après un infarctus du myocarde et chez ceux dont la fraction d’éjection est réduite.
Nous avons cherché à étudier l’utilisation de cette thérapie dans des cliniques spécialisées
en fonction cardiaque, en milieu rural et en milieu urbain.
Méthodes
Il s’agissait d’une étude rétrospective de cohorte réalisée dans 3 cliniques spécialisées
en fonction cardiaque de la Nouvelle-Écosse, dont 2 en milieu rural. De 2006 à 2011,
tous les patients dont la fraction d’éjection ventriculaire gauche initiale était
≤ 35 % étaient inclus. Les taux d’aiguillage, l’implantation de DCI et la mortalité
étaient comparés entre les groupes en milieu urbain et les groupes en milieu rural.
Résultats
L’étude comptait 922 patients, dont 636 de la clinique en milieu urbain, et 286 des
cliniques en milieu rural. Les taux d’aiguillage étaient plus élevés dans la clinique
en milieu urbain que dans les cliniques en milieu rural (80,4 % vs 68,3 % ; P = 0,024). Les taux de refus d’aiguillage étaient plus élevés en milieu rural (13,7
% vs 2,1 % ; P < 0,0001). Les taux d’aiguillage plus élevés étaient associés au milieu urbain (ratio
d’incidence approché [RIA], 1,81 ; intervalle de confiance [IC] à 95 %, 1,01-3,26 ;
P = 0,047), et à un plus jeune âge (RIA, 0,96 ; IC à 95 %, 0,93-0,99 ; P = 0,003) ; les taux d’aiguillage plus faibles étaient observés chez les femmes (RIA,
2,29 ; IC à 95 %, 1,13-4,63 ; P = 0,021). La mortalité était significativement associée à un âge plus avancé, à l’absence
d’aiguillage, à la présence de comorbidités (insuffisance rénale, diabète, maladie
vasculaire périphérique) et au milieu rural.
Conclusions
Les cliniques spécialisées en fonction cardiaque ont un taux élevé d’aiguillage convenable
pour les DCI en prévention primaire, mais les taux d’aiguillage pour les traitements
de sauvetage restent plus faibles dans les milieux ruraux. Cette disparité dans l’accès
aux soins est associée à une mortalité accrue et nécessiterait une attention particulière
pour prévenir les décès inutiles.
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Article Info
Publication History
Published online: January 16, 2017
Accepted:
October 12,
2016
Received:
April 13,
2016
Footnotes
See editorial by Wilton and Lyons, pages 420–421 of this issue.
See page 442 for disclosure information.
Identification
Copyright
© 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
