Atrial Functional Tricuspid Regurgitation (AFTR) Is Associated with Better Outcome After Tricuspid Transcatheter Edge-to-Edge Repair (T-TEER) Compared to Ventricular FTR (VFTR)

Background: Transcatheter tricuspid edge-to-edge repair (T-TEER) is widely used to treat atrial (AFTR) and ventricular (VFTR) functional tricuspid regurgitation (FTR). Methods: The outcome of 136 patients treated with T-TEER for severe AFTR or VFTR was analyzed using a composite endpoint of all-cause death and rehospitalization for decompensated heart failure. AFTR was defined as TR in the context of left ventricular ejection fraction ≥50%, right ventricular fractional area change (RVFAC) ≥ 35% and sPAP ≤ 50 mmHg. Results: Patients with VFTR (N = 109) and AFTR (N = 27, 19.9%) were both elderly (82.0 {IQR: 74.5–84.5} vs. 82.0 {IQR: 75.0–84.0} years, p = 0.98) and had similar interventional risk according to the EuroScore II (6.1 {4.0–9.8} vs. 4.7 {3.6–9.6} %, p = 0.3). Atrial fibrillation was equally frequent in both groups (89.9 vs. 88.9%, p = 0.88). AFTR patients were significantly more often female (56.0 vs. 77.8%, p = 0.04) and had lower NT-proBNP (3600.0 {1706.0–6302.0} vs. 1988.0 {1034.8–3723.3} pg/mL, p < 0.01). While RVFAC (29.5 ± 8.6 vs. 42.1 ± 4.3%, p < 0.01) and LVEF (48.5 ± 12.3 vs. 58.6 ± 8.0%, p < 0.01) were expectedly lower in patients with VFTR, right atrial dilation (RA volume: 126.7 ± 56.5 vs. 127.6 ± 74.2 mL, p = 0.99) was similar. Successful T-TEER with TR reduction ≥ 2 degrees (96.3 vs. 92.6%, p = 0.34) was observed in both groups, and residual TR ≤ II was equally frequent (94.5 vs. 96.3%, p = 1.0). The incidence of the 1-year composite endpoint was significantly higher (34.3 vs. 12.0%) in patients with VFTR (log-rank p = 0.02). AFTR was inversely associated with the composite endpoint (HR: 0.21, 95% CI: 0.06–0.7, p < 0.01) in multivariate Cox regression. Conclusions: Despite equally effective TR reduction through T-TEER, a better outcome was observed in patients with AFTR.