[Secondary atrial tricuspid regurgitation: an underestimated but increasingly clinically relevant valve disorder].

Atrial secondary tricuspid regurgitation (A-STR) is a complex and increasingly recognized form of valvular heart disease that arises primarily due to right atrial and tricuspid annular dilation in the absence of intrinsic leaflet pathology. Unlike ventricular secondary tricuspid regurgitation, which is driven by right ventricular remodeling, A-STR is predominantly associated with atrial fibrillation, heart failure with preserved ejection fraction, and other conditions that lead to chronic right atrial remodeling. This condition has been underappreciated despite its significant prevalence and impact on patient morbidity and mortality. Echocardiography is the primary diagnostic tool for diagnosing and assessing patients with A-STR. The natural history of A-STR is unfavorable, with potential worsening over time, particularly if the underlying conditions are not properly treated. Treatment options include cardioversion of atrial fibrillation and medical treatment of heart failure with preserved ejection fraction, which may promote reverse remodeling of the right heart structures and reduce STR severity in some cases. Surgical tricuspid valve annuloplasty remains the gold standard for severe cases, but transcatheter interventions are emerging as potential alternatives. This review provides a comprehensive overview of A-STR, encompassing its epidemiology, pathophysiology, diagnostic approaches, and treatment strategies. By synthesizing current evidence and highlighting gaps in knowledge, this paper aims to guide clinicians in the management of this challenging condition and to inspire future research.