While leaflet resection is the most common repair technique for primary mitral regurgitation
(MR), there has been a growing interest towards the use of artificial chords for the
repair of primary MR. Neo-chord sizing is paramount to the effectiveness of this technique;
inappropriate lengths can result in restriction or residual prolapse of the diseased
segments. In previous reports, sizing was typically performed on the arrested heart
either by visual inspection or with a caliper. Herein, we report our initial experience
with a standardized length for multi-loop neo-chord for posterior leaflet (PL) prolapse
based on a pre-operative measurement.
METHODS AND RESULTS
Between October 2017 and October 2020, 18 patients who underwent mitral valve (MV)
repair for MR due to PL prolapse were included in the study. Pre-operative transesophageal
echocardiogram (TEE) was used to determine the optimal neo-chordae length, which was
the distance between the papillary muscle tip and desired coaptation point: consistently,
16mm was the optimal neo-chordae length regardless of the affected PL segment. Multi-loop
neo-chords were prepared prior to incision. The procedure was performed minimally
invasively in 6 patients. Pre-measured 16 mm neo-chords were used to treat prolapsing
segments either at the level of P1 (28%), P2 (39%) or P2-P3 (33%). An incomplete semi-rigid
band was implanted in all cases. Post-procedural TEE was performed to confirm MV competency.
The mean age was 65±13 years and majority were male (74%). Patients either exhibited
moderate-severe (11%) or severe (89%) MR. The mean aortic cross-clamp time was 101±17
min. The mean ICU and hospital length of stay were 2±1 and 7±5 days, respectively.
No patient required conversion to MV replacement. There was no in-hospital mortality.
None exhibited systolic anterior leaflet motion, residual MR greater than grade 2,
or mitral stenosis. The mean post-procedural coaptation length was 11±3 mm. At discharge,
the mean transmitral gradient and left ventricular ejection fraction were 3±1 mmHg
and 61±7%, respectively.
Our results show that a standard neo-chord length of 16mm can sufficiently correct
MR arising from PL prolapse, while avoiding SAM of the anterior leaflet and mitral
stenosis and irrespective of the affected segment. However, long-term outcomes are
warranted to validate the durability of this approach.