Transapical off-pump mitral valve repair with NeoChord™ implantation: An early single-center Portuguese experience

Introduction

Transapical off-pump NeoChord DS1000™ implantation is a minimally invasive surgical mitral valve repair (MVr) procedure to treat degenerative mitral regurgitation (MR), which is performed using the NeoChord DS1000™ system with two and three-dimensional transesophageal echocardiographic guidance on a beating heart. It has been demonstrated to be safe and effective in carefully selected patients.

Objective

The authors aim to analyze short-term clinical and echocardiographic results after mitral valve repair using the NeoChord™ system.

Methods

All patients that underwent transapical off-pump mitral valve repair with NeoChord™ implantation at our center, between December 2017 and December 2019, were included. The procedure was performed by left minithoracotomy, under general anesthesia. All patients presented severe primary MR due to flail/prolapse of one leaflet (anterior or posterior).

Results

Eighteen patients were included in the analysis, the mean age was 65±15 years, 72% were male. The mean EuroSCORE II was 1.9±1.6. All patients had New York Heart Association (NYHA) class ≥ II. Mean effective regurgitant orifice area was 1.0±0.4 cm², with a mean regurgitant volume 146±42 mL, and a mean leaflet-to-annulus index of 1.29±0.14. MR was due to leaflet prolapse in 50% (N=9), and flail leaflet in 50% (N=9). Anatomic type A (isolated P2 defect) was the predominant form in 66.5% (N=12). Successful repair, defined by none, trace or mild mitral regurgitation, by implantation of two to four neochordae, was achieved in all 18 patients. No major complications arose intra-procedurally. The median follow-up was 194 days. NYHA class was ≤II in 94.5% patients at six-month follow-up, which represented a significant improvement in symptomatic status (p=0.002). At follow-up, 72% of patients (N=13) had grade ≤2 MR. There was a significant reduction in mean indexed left atrium volume (63±7 mL/m² vs. 45±6 mL/m², p=0.038), mean indexed left ventricular end-diastolic volume (87±7 mL/m² vs. 79±9 ml/m², p=0.001), and pulmonary arterial systolic pressure (44±4 vs. 31±8 mmHg, p=0.002). The re-intervention rate was 11.1% (N=2, both patients underwent reintervention, either a re-do NeoChord™ or conventional MV repair on-pump surgery). No major adverse cardiac or cerebrovascular events were registered.

Conclusions

In selected patients, minimally invasive MVr using the NeoChord™ system is safe, effective and reproducible. Early clinical and echocardiographic results suggest a significant symptomatic improvement, sustained MR grade decrease, and favorable left cardiac chamber remodeling, with low re-intervention rates. These results warrant further confirmation in larger cohorts, on longer period of follow-up.