Exercise testing in patients with tricuspid regurgitation undergoing transcatheter tricuspid valve intervention.

Background: Transcatheter tricuspid valve intervention (TTVI) has shown promising results with persistent reduction of tricuspid regurgitation (TR) and improvements in functional class and quality of life (QOL).

Objectives: To analyze the impact of TTVI on maximal and submaximal exercise capacity (SEC).

Methods: Constant work-rate exercise-time (CWRET) testing reflects SEC, which is more likely to be relevant for daily life activities and provides more differentiated physiological insight into the nature of exercise intolerance. Thus, 30 patients undergoing TTVI (21 direct annuloplasty and 9 edge-to-edge repair) received cardiopulmonary exercise testing (CPET) and CWRET (at 75% of maximum work rate in the initial CPET) before and 3 months after TTVI.

Results: Patients' age was 80.5 [74.8-82.3] years and 53.3% were female. TR reduction ≥ 2 grades was achieved in 93.3% (TR grade ≤ moderate in 83.3%). Echocardiography revealed improved right ventricular (RV) characteristics with decreased RV basal diameter (47.0 mm [43.0-54.3] vs. 41.5 mm [36.8-48.0]; p < 0.001) and decreased inferior caval vein diameter. CWRET testing showed a significantly improved SEC (246.5 s [153.8-416.8] vs. 338.5 s [238.8-611.8] p = 0.001). Maximum oxygen uptake showed a positive trend without statistically significant differences (9.9 ml/min/kg [8.6-12.4] vs. 11.7 ml/min/kg [9.7-13.3]; p = 0.31). In contrast to the six-minute-walking distance (6MWD), SEC correlated moderately with effective regurgitation orifice area reduction (r = 0.385; p = 0.036), increased cardiac output (r = 0.378; p = 0.039), and improved QOL (r = 387; p = 0.035).

Conclusion: Improvements in exercise capacity after TTVI mainly occur in the submaximal rather than in the maximal exercise range and correlate with hemodynamic effects and QOL. This may have a methodological impact on assessment of exercise capacity in these patients.