Loop technique for degenerative mitral regurgitation due to extended prolapse

Abstract

Purpose: Our study aims to examine the midterm outcomes of the loop technique for extended mitral valve (MV) prolapse patients.Methods: From October 2008 to August 2020, we performed MV repairs in 407 patients with severe mitral regurgitation (MR). Follow-up ranged in duration from 287 to 2899 days (median, 872 days). The prolapse extensiveness (p-score) was determined based on the ratio of prolapsing segment's areas to whole area. We divided the whole MV into 10 segments (A1, A2 medial, A2 lateral, A3, P1, P2 medial, P2 lateral, P3, AC, and PC). Patients were categorized into three groups according to the p-score: simple (0.1-0.2), intermediate (0.3-0.4), and extensive (0.5-0.9).Results: All patients underwent MV repair with the loop technique. The rates of freedom from significant (moderate to severe or severe) MR at 5 and 7 years after surgery were 91% and 91%, respectively. There were 252, 115, and 40 patients in simple group, intermediate group, and extensive group, respectively. The following were significantly increased in extended group: Barlow disease (23/40 patients, p < .001), the number of loops (p for trend < .0001), and the technique score (p for trend < .0001). The rates of freedom from significant MR at 7 years after surgery were 92% in simple group, 87% in intermediate group, and 94% in extended group, respectively (p = .995).Receiver-operating characteristic curves showed a postoperative mild MR with a sensitivity of 86% and a specificity of 68% for predicting significant MR recurrence.Conclusions: MV repair using the loop technique was useful even in groups with extended prolapse.

Midterm Results of Mitral Valve Repair Using Loop Technique With Simple Height Reduction of the Large Posterior Leaflet

“…We previously reported surgical results of loop technique for degenerative MR due to extended MV prolapse. 14 Surprisingly, the midterm results of extended prolapse patients are superior to those of intermediate and simple prolapse patients. We consider that enough coaptation was achieved by loop technique in patients with bileaflet prolapse, extensive prolapse, or Barlow's disease, which led to better results for MR recurrence.…”

“…Detailed information on how to calculate the p-score was described in our previous reports. 14 The combination of posterior leaflet lesions and commissural lesions was classified into posterior leaflet lesions, and the combination of anterior leaflet lesions and commissural lesions was also classified into anterior leaflet lesions. 14…”

Surgical mitral valve repair technique considerations based on the available evidence

“…[38][39][40] The respect approach consists of implanting polytetrafluoroethylene (PTFE) neochordae into the prolapsing segments (Figure 2b). Studies on chordal replacement (respect concept) show good long-term results with good survival, [31,35,40] low rates of MR recurrence, [11,[41][42][43] and mitral valve reoperations. [37,44,45] Since the respect approach in principle leaves more valve tissue, larger rings may be selected for annuloplasty.…”

“…[7] Current repair strategies, therefore, consist of annuloplasty plus either classic resection of the prolapsing segments [8,9] or respecting the available tissue and resuspending the prolapsing segments with Gore-Tex neochordae. [10][11][12] Patients with endocarditis also belong to the group of structural MR. However, they are comparably infrequent, and the ability to repair depends on both the severity and presentation of the endocarditis as well as the surgeon's mitral expertise.…”