Atrial functional tricuspid regurgitation: An underappreciated cause of secondary tricuspid regurgitation

Secondary tricuspid regurgitation (TR) caused by right ventricular enlargement in the setting of left heart disease/pulmonary hypertension has been well described. In contrast, that associated with right atrial enlargement-atrial functional TR (AF-TR)-remains largely underappreciated. AF-TR most often occurs in the setting of lone atrial fibrillation, although it is also seen in its absence (idiopathic AF-TR). Several recent studies have found that the prevalence, hemodynamic significance, and prognosis of AF-TR are not inconsequential, suggesting increased physician awareness of this novel clinical entity is warranted. This article discusses the pathogenesis, echocardiographic findings, and treatment of this underappreciated cause of secondary TR.