Atrial functional tricuspid regurgitation in severe atrial cardiomyopathy: prevalence and prognostic significance

Background The prevalence and prognostic significance of atrial functional tricuspid regurgitation (AF-TR) in patients with severe atrial cardiomyopathy (AtCM) remain incompletely defined. Purpose To evaluate the prevalence, determinants, and prognostic significance of AF-TR in patients with severe AtCM. Methods We conducted a prospective observational study including consecutive patients with severe left atrial dilatation (left atrial volume index ≥50 mL/m²) admitted to a tertiary cardiology department. Patients with left ventricular ejection fraction <50%, primary valvular disease, left ventricular hypertrophy, significant pulmonary hypertension, or implanted cardiac devices were excluded. All patients underwent comprehensive echocardiography, including volumetric and speckle-tracking analysis. Tricuspid regurgitation (TR) was graded according to current guidelines. Multivariable logistic regression was used to identify determinants of severe AF-TR. Cox proportional hazards regression analysis was performed to identify predictors of all-cause mortality. Results A total of 214 patients were included (mean age 73.8±9.6 years; 59% women). Mild AF-TR was present in 51%, moderate in 30%, and severe in 19%. Over a median follow-up of 40 months (IQR 23–57), overall mortality was 25%. Mortality increased according to AF-TR severity (16% in mild, 22% in moderate, and 55% in severe AF-TR; log-rank p<0.0001). Multivariable logistic regression analysis demonstrated that severe AF-TR was independently associated with heart failure (OR 12.8, 95% CI 2.7–21.4; p=0.001), permanent atrial fibrillation (OR 2.9, 95% CI 1.2–6.9; p=0.014), female sex (OR 2.9, 95% CI 1.2–7.2; p=0.020), and chronic kidney disease (OR 2.8, 95% CI 1.1–7.5; p=0.039). In a separate model including echocardiographic parameters, right atrial volume index (OR 1.10 per 1 mL/m² increase, 95% CI 1.05–1.17; p=0.001) and tricuspid annular diameter (OR 1.08 per 1 mm increase, 95% CI 1.02–1.16; p=0.016) were independently associated with severe AF-TR. In Cox regression analysis, heart failure (HR 3.4, 95% CI 1.5–7.6; p=0.003), severe AF-TR (HR 2.8, 95% CI 1.5–5.2; p=0.001), and chronic kidney disease (HR 2.3, 95% CI 1.3–3.8; p=0.003) independently predicted mortality. Conclusion In patients with severe atrial cardiomyopathy, AF-TR is highly prevalent and identifies individuals at increased risk of long-term mortality, underscoring the importance of systematic evaluation and timely management of tricuspid regurgitation.