Meta-analyses: Mitral contour system delivers good clinical, patient-centered results
According to two meta-analyses, a mitral contour system for functional mitral regurgitation conferred not only good clinical results, but also positive patient-based outcomes.
As Healio previously reported from Cardiovascular Research Technologies, patients with congestive HF and grade 2 to 4 functional mitral regurgitation despite medical therapy who underwent transcatheter mitral valve repair (TMVR) with the mitral contour system (Carillon, Cardiac Dimensions) experienced favorable survival rates at 5 years.
In the present meta-analyses published in ESC: Heart Failure, researchers used data from the REDUCE-FMR, TITAN and TITAN II studies to evaluate the effect of the mitral contour system on outcomes, including mitral regurgitation severity, left ventricular remodeling, functional status and HF-related outcomes in addition to patient-centered outcomes such as changes from baseline in Kansas City Cardiomyopathy Questionnaire (KCCQ) overall summary score, 6-minute walk test distance and NYHA class after implantation.
“Heart failure patients often suffer from reduced quality of life and compromised physical function, which is why improving their quality of life endpoints should be the primary consideration,” Stefan D. Anker, MD, PhD, of the Berlin-Brandenburg Center for Regenerative Therapies and the department of cardiology at Charité University in Berlin, said in a press release. “Our patients don’t care if they have regurgitant volume when they come to the hospital. Their focus is around symptoms, quality of life, hospitalizations and, as the ultimate goal, long-term survival.”
According to one meta-analysis, among 139 patients, the mitral contour system improved 6-minute walk distance (mean improvement, 63 m; 95% CI, 18.8-107.2; P = .0056) and KCCQ overall summary score at 1 month (mean improvement, 15.1; 95% CI, 5.6-24.7; P = .0022). The improvements were sustained at 12 months (mean walk distance improvement, 64.1 m; 95% CI, 13.2-115; P = .0141; mean KCCQ overall summary score improvement, 12.3; 95% CI, 4.7-19.8; P = .0019).
According to the meta-analysis, more than half of participants had improved KCCQ overall summary score at 12 months by at least 5 points (60.4%; 95% CI, 47.4-72.1) and by at least 10 points (50.5%; 95% CI, 34.9-66).
Additionally, after the procedure, nearly half of the cohort experienced a NYHA class improvement of 1 or more at 1 month (67.9%; 95% CI, 37.3-88.3) and at 12 months (48.8%; 95% CI, 31.8-66.2).
In a subgroup analyses that included patients with mitral regurgitation of grade 3 or 4, the findings remained similar.
According to the study, the prevalence of all-cause mortality was 2.2% (95% CI, 0.7-6.5) at 30 days and 17.3% (95% CI, 11.8-24.5) at 1 year.
“Carillon Mitral Contour System substantially improved the quality of life KCCQ scores and 6-minute walk test distance as early as 1 month, and these benefits were sustained at 12 months,” Muhammad Shahzeb Khan, MD, researcher in the department of medicine at the University of Mississippi, and colleagues wrote. “Quality of life improvement in patients who were treated with the Carillon device was similar or better than other recently reported heart failure trials. Carillon Mitral Contour System represents an attractive new option for heart failure patients with typically poor prognosis and offers many advantages compared with other devices for functional mitral regurgitation.”
Individual patient data meta-analysis
For the second meta-analysis of the same three trials, researchers evaluated outcomes after use of the mitral contour system compared with controls, including mitral regurgitation severity, LV remodeling, NYHA class, mortality and HF hospitalization.
According to the analysis, implantation of the mitral contour system improved mitral regurgitation volume (mean difference, 9.2 mL; 95% CI, 16.11 to 2.29; P = .009) and mitral regurgitation grade (mean difference, 1.12 mL; 95% CI, 1.36 to 0.88; P < .00001) and lowered left atrial volume compared with the control group (mean difference, 7.54 mL; 95% CI, 14.9 to 0.18; P = .04).
Researchers reported that LV reverse remodeling was observed in terms of end-diastolic volume (mean difference, 16.53 mL; 95% CI, 28.61 to 44.4; P = .007) and end-systolic volume (mean difference, 8.68 mL; 95% CI, 18.69 to 1.34; P = .09); however, they observed no effect on LV ejection fraction (mean difference, 0.88%; 95% CI 1.52 to 2.38; P = .47). Researchers attributed this finding to elevated residual mitral regurgitation among patients in the control group, which falsely elevated LVEF.
In addition, use of the mitral contour system was associated with improved NYHA class (mean difference, 0.22; 95% CI, 0.24 to 0.16; P < .00001) and lower rate of HF hospitalization compared with the control group (45.3% vs. 64%; P = .04).
This study also included a subanalysis restricted to patients with mitral regurgitation of grade 3 or 4 at baseline, which had similar results. Reductions in HF hospitalization were greater among this population compared with patients with lower mitral regurgitation gradient (43.9% vs. 82.9%; P = .04).
“The number of patients and trials was modest, but the clear evidence of LV remodeling suggests this may translate into improved outcomes,” Francesco Giallauria, MD, PhD, of the department of translational medicine at ‘Federico II’ University of Naples, Italy, and colleagues wrote. “Future studies are awaited in order to define the impact on this intervention on major clinical outcomes and also to determine whether earlier intervention with the Carillon device could delay the need for the more destructive (to the mitral valve leaflets) MitraClip device.”