Value of echo-Doppler derived pulmonary vascular resistance, net-atrioventricular compliance and tricuspid annular velocity in determining exercise capacity in patients with mitral stenosis

Background: The present study sought to determine if echo-Doppler-derived pulmonary vascular resistance (PVRecho), net-atrioventricular compliance (Cn) and tricuspid peak systolic annular velocity (Sa), as parameters of right ventricular function, have value in predicting exercise capacity in patients with mitral stenosis (MS). Methods and Results: Thirty-two patients with moderate or severe MS without left ventricular systolic dysfunction were studied. After comprehensive echo-Doppler measurements, including PVRecho, tricuspid Sa and left-sided Cn, supine bicycle exercise echo and concomitant respiratory gas analysis were performed. Measurements during 5 cardiac cycles representing the mean heart rate were averaged. Increment of resting PVRecho (r=-0.416, p=0.018) and decrement of resting Sa (r=0.433, p=0.013) and Cn (r=0.469, p=0.007) were significantly associated with decrease in %V̇O ₂ peak. The predictive accuracy for %V̇O₂ peak could increase by combining these parameters as Sa/PVR_echo (r=0.500, p=0.004) or Cn·(Sa/PVR_echo) (r=0.572, p=0.001) independent of mitral valve area, mean diastolic pressure gradients or presence of atrial fibrillation. Conclusions: Measurement of PVR_echo, Cn and Sa might provide important information about the exercise capacity of patients with MS.