The following is a summary of “Residual Mitral Regurgitation Interacts With Transmitral Mean Pressure Gradient to Modify the Association With Mortality Following Transcatheter Edge-to-Edge Repair,” published in the January 2025 issue of Cardiology by Duggal et al. 

The relationship between transmitral mean pressure gradient (TMPG) after MitraClip-based mitral transcatheter edge-to-edge repair and 1-year mortality remains unclear.  

Researchers conducted a retrospective study to estimate the association between intraoperative residual mitral regurgitation (rMR), TMPG, and 1-year mortality in patients undergoing mitral transcatheter edge-to-edge repair.  

They analyzed registry data of patients with severe secondary (functional) MR using generalized estimating equations. Both rMR and TMPG were transformed nonlinearly through fractional polynomials.  

The results showed 570 patients with secondary (functional) MR undergoing mitral transcatheter edge-to-edge repair were studied across 11 centers. The majority were male (61%) with an average age of 72 ± 12 years. Most (78%) had TMPG <5 mm Hg, while 22% had TMPG ≥5 mm Hg. Post-procedural MR improved, with 95% having ≤2+ severity (76% ≤1+), 3% at 3+, and 2% at 4+, 1-year mortality was 20%. After adjusting for confounders, rMR and TMPG were associated with mortality. Odds ratios for rMR >1+ were 2.10 (95% CI, 1.88–2.35; P < 0.001). For TMPG values of 4, 6, and 8, odds ratios were 1.26 (95% CI, 1.19–1.32), 1.84 (95% CI, 1.58–2.10), and 3.13 (95% CI, 2.31–3.98), respectively, when compared to TMPG = 2 mm Hg at rMR = 1+.  

Investigators concluded the association between TMPG, and 1-year mortality exhibited a significant interaction with rMR, with larger changes in the risk of death observed at higher rMR levels for even small variations in TMPG. 

Source: ahajournals.org/doi/10.1161/CIRCINTERVENTIONS.124.014843