Objective:

This study aimed to compare characteristics and outcomes of patients rejected for TMVR treatment after anatomical screening, who were treated either conservatively with optimal medical therapy (OMT) or interventionally by edge-to-edge repair (E2E).

Methods:

Between 2016 and 2020 a total of 105 patients were screened for TMVR. 44 patients were found anatomically eligible for TMVR. Of those ineligible for TMVR, 31 patients were treated medically (OMT group) and 25 patients received E2E (E2E group). Baseline clinical and anatomical characteristics of both groups were compared and Kaplan-Meier estimates were calculated. Cox regression analysis was performed for the impact of MR reduction on all-cause mortality. Median follow-up time was 1.74 years (1.36, 2.65).

Results:

All patients were diagnosed with moderate-to-severe or severe MR. Distribution of primary (45.2% [OMT] vs. 48.0% [E2E]), secondary (45.2% [OMT] vs. 32.0% [E2E]) or mixed primary/secondary MR (9.7% [OMT] vs. 20.0% [E2E]) did not differ between groups. Age (78.0 years [75.2, 80.8] vs. 81 years [75.3, 84.0], p=0.097), EuroSCORE II (5.8% [2.9, 10.1] vs. 4.8% [3.1, 9.1], p=0.43) and left ventricular ejection fraction (LVEF) at baseline (55.0% [37.3, 60.0] vs. 55.0% [40.2, 58.8], p=0.36) were not different between patients treated with  OMT or E2E. Patients treated with OMT had higher mean transvalvular gradients (3.8 mmHg [2.0, 6.1] vs. 2.0 [1.0, 4.0), p=0.012), smaller mitral annulus diameters (34.9 mm [31.4, 40.4] vs. 41.7 [37.5, 47.1], p=0.0034) and presented more often with severe mitral annular calcification 36.7% (N=11/31, absent in all patients treated with E2E) than patients treated with E2E. Reduction of MR grade to £mild MR by E2E was achieved in 72.0% (N=18) of interventionally treated patients. One-year mortality was high in both groups. Kaplan-Meier analysis revealed no significant difference in all-cause mortality after 1 year between OMT group and E2E group (OMT 35.7%, E2E 23.6%, p=0.73) (Figure 1). After adjustment for age, sex and LVEF no impact on survival was found for the reduction of MR to lower or equal MR by E2E (HR 0.54 [0.15, 1.92], p=0.34).

Conclusions:

Patients with severe MR unsuitable for TMVR have poor outcomes, irrespective of medical or endovascular therapeutic regimen. Markers for combined mitral defects (high transvalvular gradient, valvular calcification) are more common in those offered medical therapy than in those offered E2E. Reduction of MR to £mild MR with E2E was not predictive of survival in in this single-center analysis.