STANDARDIZATION OF ARTIFICIAL CHORDAL LENGTH FOR POSTERIOR LEAFLET PROLAPSE: A SIMPLIFIED APPROACH FOR MULTIPLE SCENARIOS

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.

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.