Hypoattenuated Leaflet Thickening and Reduced Leaflet Motion After Transcatheter Tricuspid Valve Replacement

Reduced leaflet motion (RLM) induced by hypoattenuated leaflet thickening (HALT) is a known complication after bioprosthetic aortic valve replacement, associated with adverse outcomes. A similar phenomenon has been observed after transcatheter tricuspid valve replacement (TTVR) but remains unclassified.

The aim of this study was to introduce a grading system for valve thrombosis and dysfunction after TTVR and describe its clinical and echocardiographic associations.

Thirty-day follow-up computed tomographic (CT) scans from all patients undergoing orthotopic TTVR were analyzed. Grading systems for RLM_CT severity (none, mild to moderate, and severe) and HALT (0°-4°) were developed. These were correlated with clinical and echocardiographic parameters at 30 days and up to 3 years.

Among 53 patients, 45 had 30-day CT data. Moderate to severe HALT was present in 12 cases (27%). RLM_CT severity was none in 15 (33%), mild to moderate in 21 (74%), and severe in 9 (20%). HALT was correlated with RLM_CT severity (P < 0.001), and both were associated with increased transvalvular gradient (P = 0.032 and P < 0.0001) and reduced NYHA functional class improvement at 30 days (P = 0.002 and P = 0.003). RLM_CT was correlated with echocardiographic RLM (P < 0.0001), but RLM_echo was less sensitive, detecting just 6 of 9 severe cases of RLM. Similarly, severe HALT was detected on echocardiography in just 3 of 7 cases. There was no association between HALT or RLM_CT and anticoagulation strategy.

HALT and RLM_CT are common after TTVR and are associated with elevated gradients and reduced symptomatic alleviation. Transthoracic echocardiography is insensitive for detecting HALT and RLM, and routine CT imaging may aid early diagnosis, but the long-term impact of low-grade HALT and RLM_CT remains unclear.