Intraprocedural Residual Mitral Regurgitation and Survival After Transcatheter Edge-to-Edge Repair: Prospective German Multicenter Registry (MITRA-PRO)

Impact of Intraprocedural Mitral Regurgitation and Gradient Following Transcatheter Edge-to-Edge Repair for Primary Mitral Regurgitation

BACKGROUND

The impact of intraprocedural results following transcatheter edge-to-edge repair (TEER) in primary mitral regurgitation (MR) is controversial.

OBJECTIVES

This study sought to investigate the prognostic impact of intraprocedural residual mitral regurgitation (rMR) and mean mitral valve gradient (MPG) in patients with primary MR undergoing TEER.

METHODS

The PRIME-MR (Outcomes of Patients Treated With Mitral Transcatheter Edge-to-Edge Repair for Primary Mitral Regurgitation) registry included consecutive patients with primary MR undergoing TEER from 2008 to 2022 at 27 international sites. Clinical outcomes were assessed according to intraprocedural rMR and mean MPG. Patients were categorized according to rMR (optimal result: ≤1+, suboptimal result: ≥2+) and MPG (low gradient: ≤5 mm Hg, high gradient: > 5 mm Hg). The prognostic impact of rMR and MPG was evaluated in a Cox regression analysis. The primary endpoint was 2-year all-cause mortality or heart failure hospitalization.

RESULTS

Intraprocedural rMR and mean MPG were available in 1,509 patients (median age = 82 years [Q1-Q3: 76.0-86.0 years], 55.1% male). Kaplan-Meier analysis according to rMR severity showed significant differences for the primary endpoint between rMR ≤1+ (29.1%), 2+ (41.7%), and ≥3+ (58.0%; P < 0.001), whereas there was no difference between patients with a low (32.4%) and high gradient (42.1%; P = 0.12). An optimal result/low gradient was achieved in most patients (n = 1,039). The worst outcomes were observed in patients with a suboptimal result/high gradient. After adjustment, rMR ≥2+ was independently linked to the primary endpoint (HR: 1.87; 95% CI: 1.32-2.65; P < 0.001), whereas MPG >5 mm Hg was not (HR: 0.78; 95% CI: 0.47-1.31; P = 0.35).

CONCLUSIONS

Intraprocedural rMR but not MPG independently predicted clinical outcomes following TEER for primary MR. When performing TEER in primary MR, optimal MR reduction seems to outweigh the impact of high transvalvular gradients.

Cardiac Surgery 2023 Reviewed

We reviewed the cardiac surgical literature for 2023. PubMed displayed almost 34,000 hits for the search term "cardiac surgery AND 2023." We used a PRISMA approach for a results-oriented summary. Key manuscripts addressed the mid- and long-term effects of invasive treatment options in patient populations with coronary artery disease (CAD), comparing interventional therapy (percutaneous coronary intervention [PCI]) with surgery (coronary artery bypass graft [CABG]). The literature in 2023 again confirmed the excellent long-term outcomes of CABG compared with PCI in patients with left main stenosis, specifically in anatomically complex chronic CAD, but even in elderly patients, generating further support for an infarct-preventative effect as a prognostic mechanism of CABG. For aortic stenosis, a previous trend of an early advantage for transcatheter (transcatheter aortic valve implantation [TAVI]) and a later advantage for surgical (surgical aortic valve replacement) treatment was also re-confirmed by many studies. Only the Evolut Low Risk trial maintained an early advantage of TAVI over 4 years. In the mitral and tricuspid field, the number of interventional publications increased tremendously. A pattern emerges that clinical benefits are associated with repair quality, making residual regurgitation not irrelevant. While surgery is more invasive, it currently generates the highest repair rates and longest durability. For terminal heart failure treatment, donor pool expansion for transplantation and reducing adverse events in assist device therapy were issues in 2023. Finally, the aortic diameter related to adverse events and technical aspects of surgery dominated in aortic surgery. This article summarizes publications perceived as important by us. It cannot be complete nor free of individual interpretation, but provides up-to-date information for patient-specific decision-making.

Echocardiographic Profiling Predicts Clinical Outcomes After Mitral Transcatheter Edge-to-Edge Repair

BACKGROUND

Prior studies investigating the impact of residual mitral regurgitation (MR), tricuspid regurgitation (TR), and elevated predischarge transmitral mean pressure gradient (TMPG) on outcomes after mitral transcatheter edge-to-edge repair (TEER) have assessed each parameter in isolation. We sought to examine the prognostic value of combining predischarge MR, TR, and TMPG to study long-term outcomes after TEER.

METHODS AND RESULTS

We reviewed the records of 291 patients who underwent successful mitral TEER at our institution between March 2014 and June 2022. Using well-established outcomes-related cutoffs for predischarge MR (≥moderate), TR (≥moderate), and TMPG (≥5 mm Hg), 3 echo profiles were developed based on the number of risk factors present (optimal: 0 risk factors, mixed: 1 risk factor, poor: ≥2 risk factors). Discrimination of the profiles for predicting the primary composite end point of all-cause mortality and heart failure hospitalization at 2 years was examined using Cox regression. Overall, mean age was 76.7±10.6 years, 43.3% were women, and 53% had primary MR. Two-year event-free survival was 61%. Predischarge TR≥moderate, MR≥moderate, and TMPG≥5 mm Hg were risk factors associated with the primary end point. Compared with the optimal profile, there was an incremental risk in 2-year event-rate with each worsening profile (optimal as reference; mixed profile: hazard ratio (HR), 2.87 [95% CI, 1.71-5.17], P<0.001; poor profile: HR, 3.76 [95% CI, 1.84-6.53], P<0.001). Echocardiographic profile was statistically associated with the 2-year mortality end point (optimal as reference; mixed profile: HR, 3.55 [95% CI, 1.81-5.96], P<0.001; poor profile: HR, 3.39 [95% CI, 2.56-7.33], P=0.02).

CONCLUSIONS

The echocardiographic profile integrating predischarge TR, MR, and TMPG presents a novel prognostic stratification tool for patients undergoing mitral TEER.

Preprocedural Controlling Nutritional Status Score as a Predictor of Mortality in Patients Undergoing Transcatheter Mitral Valve Repair - A Single Center Experience in Japan

Background: A high score for controlling nutritional status (CONUT) due to poor nutritional status has been associated with adverse outcomes in patients with chronic heart failure. However, because little is known about the effect of CONUT score on mortality rates after transcatheter mitral valve repair, we evaluated nutrition screening tools for prognosis prediction in patients undergoing transcatheter mitral valve repair using the MitraClipTM system. Methods and Results: We retrospectively analyzed 148 patients with severe mitral regurgitation (MR) who underwent MitraClipTM implantation between April 2018 and April 2021. The preprocedural CONUT scores were assessed at the time of hospitalization, the primary outcome was all-cause death, and the analysis was of the mortality and incidence rates of cardiac events 1 year post-operation. Functional MR was of ischemic origin in the majority of patients (69.6%), with a mean left ventricular ejection fraction of 48.9±15.8%. Kaplan-Meier curves indicated that all-cause death was significantly worse in the high-CONUT score group than in the low-CONUT score group. Cox hazard analysis showed a significant association between all-cause death and CONUT score, as well as MitraScore. Conclusions: Preprocedural CONUT score, as well as MitraScore, in patients undergoing transcatheter edge-to-edge mitral valve repair may predict an increased risk of all-cause death. This knowledge should allow the heart team to accurately assess the clinical implications and prognostic benefits of the procedure in individual patients.

Transapical electrosurgical laceration and stabilization of mitral clips followed by transcatheter mitral valve replacement-A one-stop shop

Objective

Electrosurgical laceration and stabilization of mitral clips (ELASTA-CLIP) is a bail-out technique to recreate a single-orifice mitral valve after transcatheter edge-to-edge repair (TEER) with subsequent transcatheter mitral valve replacement (TMVR). This technique is a novel option for patients with significant residual mitral regurgitation after TEER with high risk for conventional surgery. The original ELASTA CLIP procedure features a transseptal approach, whereas the TMVR with the Tendyne bioprosthesis has a transapical access. Hereby we tested the hypothesis that a modified transapical ELASTA CLIP technique can be safely applied transapically allowing a straightforward one-stop shop access strategy.

Methods

We developed the procedural steps in a porcine passive-beating heart model and applied the modified technique with subsequent TMVR in 2 consecutive patients with severe mitral regurgitation after previous TEER. Patients were followed up to 30 days.

Results

The modified transapical ELASTA CLIP procedure was successful in both patients. The mean total procedure time was 118 minutes, and the mean fluoroscopy duration 22 minutes. At 30 days' follow-up, both patients were alive without bleeding complications, reintervention, or prosthetic valve dysfunction.

Conclusions

The modified transapical ELASTA CLIP procedure is technically feasible and safe at 30 days. Procedure times are lower compared with previous reports of the original transseptal approach.