Mid to Long-term Echocardiographic Follow-up of Patients Undergoing Transcatheter Tricuspid Valve-in-Valve Replacement for Degenerated Bioprosthetic Valves: First Single-Center Report from Iran

Abstract

Background: Transcatheter tricuspid valve-in-valve (TTViV) replacement has become an alternative treatment in high-risk patients with bioprosthetic valve degeneration. This is the first report on the mid to long-term echocardiographic findings of patients who underwent TTViV replacement in a cardiac referral center in Iran. 
 Methods: Data of 12 patients, consisting of 11 women and 1 man, who underwent TTViV replacement between 2015 and 2021 were reviewed retrospectively. The patients underwent echocardiography before the procedure and at a mean follow-up time of 3.17±1.75 years. 
 Results: All the patients had New York Heart Association (NYHA) function class III/IV before TTViV. Six patients had tricuspid regurgitation, 1 had tricuspid stenosis, and 5 had both. All the patients had successful TTViV. The mean time from the initial valve surgery to TTViV was 6.25±2.45 years. At follow-up, 2 patients had died: 1 due to COVID-19 pneumonia and 1 without a known cause. The remaining 10 patients experienced improvements in the NYHA functional class. Echocardiographic measures showed significant improvements. Transvalvular mean gradient pressure decreased from 7.08±1.98 mm Hg to 5.29±1.63 mm Hg (P=0.028), tricuspid valve pressure half time decreased from 245.00±49.46 ms to 158.64±57.41 ms (P=0.011), tricuspid regurgitation gradient decreased from 39.91±7.31 mm Hg to 26.72±8.99 mm Hg, and left ventricular ejection fraction increased from 47.71±4.70% to 49.79±4.58% (P=0.046). There was no significant paravalvular or transvalvular leakage at follow-up.
 Conclusion: This is a single-center report on the mid and long-term echocardiographic follow-up of patients after TTViV replacement. Our study showed that TTViV was a safe and efficient method in treating high-risk patients with degenerated bioprosthetic tricuspid valves and had favorable echocardiographic and clinical results.