Improved Cardiac Remodeling Following TTVR, TTVA

Two recent studies published in JACC: Cardiovascular Interventions focus on improved cardiac remodeling following transcatheter valve replacement (TTVR) and transcatheter valve annuloplasty (TTVA).

The first, a single-center, retrospective, shorter-term TTVR study conducted by Robin Le Ruz, MD, Rebecca T. Hahn, MD, FACC, et al., analyzed 80 TTVR patients (median age, 81; 65% women), 88% of whom had baseline massive/torrential tricuspid regurgitation (TR). The replacements (80% used the EVOQUE system) were a technical success in 90% of patients, and 96% presented with only mild or less TR post implantation.

Results at a median follow up of 40 days showed that TTVR was associated with a reduction in right ventricular (RV) end diastolic volume (EDV; 138.2 mL/m² to 59.5 mL/m²; p<0.001) and increase in septal curvature and stroke volume, leading to a 65% increase in effective RVEF and 20% increase in RV coupling.

Additionally, this reduction in RVEDV was reciprocal with an increase in left ventricular (LV) EDV (49.6 mL/m² to 57.9 mL/m²; p=0.001). Greater discordance of these two volumes at baseline, as indicated by an average eccentricity index (aEI) ≥1.25, led to greater reverse remodeling, lower follow-up NT pro-BNP levels and greater symptom improvement.

On the eccentricity index, the study authors write, “Our findings add to the growing literature supporting the use of multi-modality imaging to defining subpopulations of patients that may derive greater benefit from TTVR and by which shared decision-making about device choice could be made.”

In an accompanying editorial comment, Muhammed Gerçek, MD, and Felix Rudolph, MD, add that “Incorporating such imaging biomarkers into next-generation risk models could refine patient selection and predict tolerance to sudden afterload shifts.”

The second, longer-term TTVA study, by Caroline Hasse, MD, et al., followed 156 patients (median age, 79 years; 76% women; 89% with atrial fibrillation) undergoing TTVA for severe TR (27% with massive and 42% with torrential) using the Cardioband system. The procedure was successful in 62% of patients, and 37% still had severe or greater TR at discharge.

Results at a median follow-up of 435 days showed that 71% of patients had a TR reduction ≤2+, and 68% improved in NYHA functional class ≤III (p<0.001 for both) following TTVA. Compared with baseline, right atrial area (36.0 vs. 30.4 cm²), RV length (67.5 vs. 63.7 mm), RV midventricular dimension (42.6 vs. 35.6 mm) and RV basal dimension (47.8 vs. 42.6 mm) were all significantly reduced at follow-up (p<0.001 for all).

Torrential to severe TR reduction still led to remodeling (RV basal diameter, 50 vs. 44 mm; p=0.007) and additionally, right heart remodeling was associated with a decrease in vena contracta width (odds ratio, 1.14; p=0.015).

Hasse, et al., note that in the study, residual TR ≥3 at discharge was associated with an elevated mortality rate compared with TR <3 (26% vs. 13%; p=0.042). “Residual TR therefore must be taken seriously. Close clinical follow-up and the evaluation of further treatment options, such as staged edge-to-edge repair, should be carefully taken into consideration in this vulnerable ‘high-risk-cohort,’” they write.

While “the investigators should be commended for assembling a large cohort of patients treated with a single device and for providing a comprehensive clinical and echocardiographic evaluation,” write David Messika-Zeitoun, MD, PhD; Maurice Enriquez-Sarano, MD, FACC; and Julien Dreyfus, MD, PhD, in an accompanying editorial comment, they add that in addition to residual TR severity – procedural complexity, patient selection and timing of intervention all remain crucial concerns for future work.