Currently there are an estimated 300-600 adults living in Switzerland with congenital heart disease (CHD) and a right ventricle (RV) in subaortic (systemic) position. This includes adults with prior atrial switch operations for complete transposition of the great arteries (D-TGA) and adults with congenitally corrected transposition of the great arteries (ccTGA).
Although midterm survival is favorable, late outcome is compromised by ventricular dysfunction of the systemic RV, end-stage heart failure, and premature death. Currently, the only established end-stage therapy for a failing systemic RV is heart transplantation. Given the ubiquitous shortage of donor organs and the number of adults at risk, medical options to improve the fate of patients with a systemic RV are urgently needed. PDE-5 inhibition increases contractility in experimental models of RV hypertrophy, but not in the normal RV. SERVE study aim to assess the effect of PDE-5 inhibition with Tadalafil on RV size and function, exercise capacity and neurohumoral activation in adults with a systemic RV over a 3-year follow-up period.