Thirty-day and one-year outcomes following transcatheter mitral valve edge-to-edge repair versus transapical mitral valve replacement in patients with left ventricular dysfunction.

Background: A comparison of 30-day and 1-year clinical outcomes in patients with pre-existing left ventricular (LV) dysfunction undergoing transcatheter mitral valve edge-to-edge repair (TEER) or transcatheter transapical mitral valve replacement (TMVR) has not previously been reported. Aims: We aimed to compare 30-day and 1-year rates of all-cause and cardiovascular mortality as well as rehospitalisation for heart failure (HFH). Methods: All patients with severe (≥3+) symptomatic mitral regurgitation (MR) and an LV ejection fraction ≤50% who underwent TEER or TMVR over a 5-year period were evaluated. Results: Ninety-six patients (50 TEER, age 80±9 years, 70% secondary MR and 46 TMVR, age 72±9 years, 91% secondary MR) were studied. Baseline demographic and transthoracic echocardiogram characteristics were well-matched, with the exception of age (TEER 80±9 vs TMVR 72±9; p=0.01). Successful device implantation occurred in 96% of TEER patients and 97.8% of TMVR patients. Ninety-two percent of TEER patients had ≤2+MR predischarge, whilst no TMVR patient had ≥1+MR (p<0.01). No significant difference in the combined endpoint of 30-day all-cause mortality or HFH was observed (p>0.05). At 1 year, freedom from all-cause mortality and HFH was 79.2% across the entire study population but was significantly higher in patients undergoing TEER (TEER: n=45 [90%] hazard ratio 11.26, 95% confidence interval [CI]: 10.59-11.93 vs TMVR: n=39 [67.4%] 95% CI: 10.09-11.33; p=0.008). Conclusions: Despite comparable rates of successful device implantation, MR reduction, and 30-day all-cause mortality/HFH, TEER patients had lower all-cause mortality and HFH rates at 1 year.