Etiology, epidemiology, pathophysiology and management of tricuspid regurgitation: an overview

Significant tricuspid regurgitation (TR) is a common finding, affecting about one in twenty-five subjects among the elderly and presenting more frequently in women than in men. This review summarizes data concerning etiology, epidemiology, pathophysiology and management strategies of TR. The tricuspid valve (TV) has a broad anatomical variability. Classically, TR has been distinguished as primary and secondary or functional TR (FTR), with the latter being the most prevalent. FTR is a multifactorial disorder, resulting from maladaptive right ventricular remodeling secondary to pulmonary hypertension or from atrial fibrillation leading to dilation of the right atrium, tricuspid annulus and base of the right ventricle, with pathological TV coaptation. Thus two main types of FTR can be identified: pulmonary hypertension-FTR and idiopathic-FTR, depending on which factor, ventricular or atrial respectively, is the primum movens of the disease. Appreciable evidence suggests that significant TR leads to worsening prognosis regardless of the underlying etiology and should be addressed as a separate therapeutic target. The treatment of TR in patients undergoing left-sided cardiac surgery is well established. Isolated surgical repair of TR is instead rarely performed because patients are often deemed inoperable due to prohibitive risk. Besides, perioperative mortality remains higher than for any other valve. Several transcatheter TV replacement and repair systems, the latter mostly borrowed from percutaneous treatment systems of mitral regurgitation or from TV repair surgical techniques, have shown efficacy and safety when used on the TV. These could provide an effective treatment option for patients not eligible for surgery.