Predictors for the Development of Severe Tricuspid Regurgitation with Anatomically Normal Valve in Patients with Atrial Fibrillation

BACKGROUND AND AIMS: Atrial fibrillation (AF) may be a risk factor for severe functional tricuspid valve regurgitation (FTR). We aimed to determine the predictors of severe FTR in patients with AF. METHODS AND RESULTS: From our echocardiographic laboratory database, we searched for and reviewed the medical records of consecutive patients with severe FTR and AF seen at Mayo Clinic in Arizona from 2002 through 2009. Our search identified 42 patients who met all inclusion criteria. These patients (cases) with severe FTR and AF were compared with 38 patients (controls) with AF who had no greater than mild tricuspid regurgitation. Case patients with severe FTR were older than controls (mean, 81 years vs. 76 years; P < 0.001) and more frequently had chronic AF (69% vs 26%; P < 0.001). Mean right atrial volume (86 mL/m(2) vs 46 mL/m(2) ; P < 0.001), right ventricular volume (42 mL ± 33 mL vs 22 mL ±8 mL; P < 0.001) and tricuspid annular diameter (3.6 cm vs 3.0 cm; P < 0.001) were larger in cases than in controls. Patients with severe FTR also had a higher prevalence of right-sided heart failure (69% vs 16%; P < 0.001). After adjusting for age and gender, right atrial and right ventricular volumes were independent predictors for the development of severe FTR in patients with AF (odds ratio, 1.7 95% CI, 1.3-2.8 for every 10 mL/m(2) increase in right atrial volume; P = 0.0002 and odds ratio, 3.1 95% CI, 1.5-8.9 for every 10 mL increase in right ventricular volume; P = 0.0002). CONCLUSIONS: Severe FTR occurs in older patients with chronic AF as a result of marked right atrial and right ventricular dilatation; and enlargement of the tricuspid annulus in the absence of pulmonary hypertension. More importantly, severe FTR leads to increased prevalence of right-sided heart failure underscoring the nonbenign nature of chronic AF.