Percutaneous edge‐to‐edge repair of severe mitral regurgitation using the MitraClip XTR versus NTR system

Abstract

Background Transcatheter mitral valve repair (TMVR) has shown to improve symptoms and functional capacity in patients with severe mitral valve regurgitation (MR). Novel device developments provide the technology to treat patients with complex anatomies and large coaptation gaps. Nevertheless, the question of superiority of one device remains unanswered. We aimed to compare the MitraClip XTR and MitraClip NTR system in a real world setting. Hypothesis TMVR with the MitraClip XTR system is equally effective, but associated with a higher risk of leaflet injury. Methods We retrospectively analyzed peri‐procedural and mid‐term clinical and echocardiographic outcomes of 113 patients treated for severe MR between March 2018 and August 2019 at the University Hospital of Munich. Results Postprocedural MR reduction to ≤2+ was comparable in both groups (XTR: 96.1% vs. NTR: 97.6%, p = .38). There was a significant difference in a composite safety endpoint of periprocedural Major adverse cardiac and cerebrovascular events (MACCE) including leaflet injury between groups (XTR 14.6% vs. NTR 1.7%, 95% CI [2.7, 24.6], p = .012). After a median follow‐up of 8.5 (4.4, 14.0) months, durable reduction of MR was confirmed (XTR: in 91.9% vs. NTR: 96.8%, p = .31) and clinical and symptomatic improvement was comparable in both groups accordingly. Conclusion While efficacy was comparable in both treatment groups, patients treated with the MitraClip XTR systems showed more events of acute leaflet tear and single leaflet device attachment (SLDA). A detailed echocardiographic assessment should be done to identify risk candidates for acute leaflet injury.

Transcatheter edge‐to‐edge repair for secondary mitral regurgitation with third‐generation devices in heart failure patients – results from the Global EXPAND Post‐Market study

“…Of relevance for the application of different clip sizes could be the reported association of usage of a larger device with more SLDAs and leaflet tears. 9 Leaflet adverse events within EXPAND have been further analysed by an expert panel. 10 Reassuringly, only two peri-procedural SLDA were reported, with further six SLDA through 30 days and no other leaflet related adverse events through 1 year.…”

“…This 1.9% rate of SLDA is lower than the very early experience with different MitraClip devices reported before. 9,17 This could be due to the aetiology of SMR. In SMR, the prevalence of fragile and degenerative leaflets or extensive mitral annulus calcifications should be low.…”

“…These advances could translate into amelioration of heart failure symptoms and potentially improved prognosis in SMR patients, who would otherwise be denied M-TEER due to anatomic difficulties. Initial 9 The present investigation aimed to evaluate the real-world experience with two different sizes of the third generation of MitraClip devices in patients with SMR from the Global EXPAND study with centrally adjudicated clinical and echocardiographic outcomes.…”

Acute Leaflet Injury During Percutaneous Edge-to-Edge Mitral Valve Repair

“…3 Patients with thinner mitral valve (MV) leaflets (such as in functional, secondary MR) and patients with more fragile tissue would be at higher risk of leaflet injury. The third-generation XTR system carries higher rates of leaflet injury than the original NT MitraClip (Abbott) 3 due to its larger size (12 vs 9 mm cases-anesthesia-analgesia.org 3 clip arm length) and greater number of frictional elements (6 vs 4), causing increased leaflet stress. 3,4 Incidence of leaflet damage with the fourth-generation devices which allow for independent leaflet grasping has yet to be thoroughly studied.…”

A Practical Approach to Combined Transcatheter Mitral and Tricuspid Valve Intervention

“…When planning TV TEER procedures, the choice of device can present a challenge given that these devices were developed for the mitral valve, whereas tricuspid valve leaflets are thinner and more fragile and severe TR tends to involve larger leaflet malcoaptation gaps. Some evidence from MV TEER has shown that the XTR clip leads to more SLDA and leaflet tearing ( 57 ), however the length of the XTR device is theoretically ideal when treating severe TR as most patients have malcoaptation gaps. The use of MitraClip XTR vs. NTR devices has been shown to achieve a higher procedural success rate (TR ≤ 2+ 80% vs. 70%), was able to treat TR with larger coaptation defects including those with torrential TR and lead to a greater reduction in TR.…”