Longitudinal right ventricular function as a predictor of functional capacity in patients with mitral stenosis: an exercise echocardiographic study.

Background: The influence of right ventricular (RV) function on exercise capacity has been poorly explored in mitral stenosis (MS). The objective of this study was to assess the determinants of functional status with exercise echocardiography in MS.

Methods: Thirty-nine patients (55 +/- 12 years, 29 female) with MS (1.3 +/- 0.5 cm(2)) underwent an exercise echocardiography (14 patients had previous balloon valvuloplasty). RV function was assessed by tricuspid annulus S-wave velocity (Tric-S) and tricuspid annular plane systolic excursion (TAPSE).

Results: Tric-S correlated with TAPSE (P = .03), cardiac output (P = .006), and mitral valve area (P = .009). With exercise, Tric-S and TAPSE increased significantly (11.3 +/- 3.1 cm/s to 15.5 +/- 3.4 cm/s and 21.2 +/- 5.2 mm to 24.0 +/- 5.8 mm, respectively, both P < .05). TAPSE was lower in patients in New York Heart Association class 3 or 4. In multivariate analysis, Tric-S at rest (beta = 0.34, P = .006) and mitral Delta mean diastolic gradient (beta = 0.34, P = .006) were the independent determinants of maximum workload.

Conclusion: Resting RV longitudinal function assessed through Tric-S is an important determinant of functional capacity in MS.