The pivotal role of tricuspid regurgitation in the failing systemic right ventricle: The "chicken and egg story".

Systemic right ventricle (SRV) is commonly encountered in patients with congenital heart disease. This nomenclature includes diseases with different anatomic features, adaptation and clinical phenotypes, and has a variable - but overall guarded - prognosis. Right ventricular fibromuscular architecture, shape, adaptation to overload conditions, rhythmic disorders and - most of all - tricuspid regurgitation (TR) contribute to the pathophysiology of SRV failure. The pivotal role of TR is complex as it is due to both the intrinsic abnormalities of the valve (specific to each phenotype) and the consequence of SRV dilation and failure. Medical therapy has not been equivocally proven to be effective for TR. Surgery (valve repair or replacement) has shown conflicting long-term results, mainly dependent on preoperative SRV function. Thus, other management options have been proposed to improve SRV function and valve competency, such as early anatomical correction, pulmonary banding, resynchronization therapy and valvular edge-to-edge percutaneous repair. The aim of this review is to discuss the mechanisms of TR and SRV failure, as well as the available therapeutic options.