Retrospective Cross-Sectional Study of Transthoracic Echocardiographic Reports in Patients Diagnosed With Aortic Regurgitation in Mashhad, Iran; to Evaluate Echocardiographic Determinants of AR Severity, With Specific Focus on STJ-Related Parameters.

Background and Aims: Aortic regurgitation (AR) is associated with characteristic changes in aortic root geometry. Data on detailed echocardiographic patterns of AR in Iranian cohorts remain limited. This study aimed to describe the echocardiographic and etiologic characteristics of patients with AR and to assess the associations between standard aortic root measurements-including the aortic annulus (AA), sinuses of Valsalva (SOV), sinotubular junction (STJ), and ascending aorta (ASC)-and AR severity. Methods: This retrospective cross-sectional study reviewed transthoracic echocardiography reports of patients diagnosed with AR ( Results: Greater AA, SOV, STJ, and ASC diameters were associated with higher AR severity in unadjusted analyzes, with SOV demonstrating the strongest relationship. All variables, including ASC, STJ, SOV, AA, and STJ/BSA, were correlated with the severity of aortic regurgitation. In multivariable ordinal regression analysis, ascending aorta diameter and the STJ/AA ratio were independently associated with AR severity, whereas STJ diameter and the STJ/BSA ratio were not significant after adjustment. STJ diameter showed no correlation with age. Degenerative and rheumatic etiologies were the most common causes of AR. Conclusion: Aortic root dimensions were associated with AR severity, underscoring the role of aortic root geometry in disease expression. The STJ/AA ratio emerged as an independently associated geometric parameter in adjusted analyzes, while STJ/BSA did not retain significance. As this was a retrospective cross-sectional analysis, findings reflect associations rather than causal relationships and require confirmation in prospective, standardized studies.