Structural Heart Transcatheter Interventions in Orthotopic Cardiac Transplant and Left Ventricular Assist Devices Recipients: A Nationwide Study

Background: The current incidence and outcomes of structural transcatheter procedures in heart transplant (HTx) recipients and left-ventricular assist devices (LVAD) carriers is unknown. Aims: To provide insights on structural transcatheter procedures performed across HTx and LVAD patients in Spain. Methods: Multicenter, ambispective, observational nationwide registry. Results: Until May/2023, 36 percutaneous structural interventions were performed (78% for HTx and 22% for LVAD) widely varying among centers (0%-1.4% and 0%-25%, respectively). Percutaneous mitral transcatheter edge-to-edge (TEER) was the most common (n = 12, 33.3%), followed by trancatheter aortic valve replacement (n = 11, 30.5%), and tricuspid procedures (n = 9, 25%). Mitral TEER resulted in mild residual mitral regurgitation in all but one case, mean gradient was <5 mmHg in 75% of them at 1-year, with no mortality and 8.3% re-admission rate. Tricuspid TEER resulted in 100% none/ mild residual regurgitation with a 1-year mortality and readmission rates of 22% and 28.5%, respectively. Finally, trancatheter aortic valve replacement procedures (n = 8 in LVADs due to aortic regurgitation and n = 3 in HTx), were successful in all cases with one prosthesis degeneration leading to severe aortic regurgitation at 1year, 18.2% mortality rate and no re-admissions. Globally, major bleeding rates were 7.9% and 12.5%, thromboembolic events 3.7% and 12.5%, readmissions 37% and 25%, and mortality 22% and 25%, in HTx and LVADs respectively. No death was related to the implanted transcatheter device. Conclusions: Most centers with HTx/LVAD programs perform structural percutaneous procedures but with very inconsistent incidence. They were associated with good safety and efficacy, but larger studies are required to provide formal recommendations.