itral stenosis (MS) is known to comprise 2 stenotic lesions: the mitral valve itself and pulmonary arteriolar stenosis, anatomically or functionally. 1,2 MS initially produces pulmonary venous hypertension and subsequently, pulmonary arterial hypertension develops because of the combined effect of back pressure, pulmonary arteriolar constriction and obliterative changes in the pulmonary vascular bed. 1,2 Pulmonary vascular resistance (PVR), representing pre-capillary resistance, reflects pulmonary arteriolar stenosis or pulmonary vascular reactivity, and is a major determinant of exercise capacity and right ventricular (RV) afterload in MS. 3 Net-atrioventricular compliance (Cn), a determinant of pressure decay across the stenotic mitral valve, is related to post-capillary resistance and is also a major determinant of inappropriate elevation of pulmonary arterial pressure during exercise. 4 could be related to increased PVR or direct RV involvement in rheumatic heart disease. 5 RV function significantly affects symptoms, exercise capacity, peri-operative mortality and postoperative results; 6 however, measurement of PVR or RV function has limitations because of the invasiveness of the procedure and the geometric complexity of the RV. Development of the Doppler technique has enabled measurement of new parameters representing PVR and RV function, 7,8 and the major advantage of these Doppler-derived parameters is that they are highly reproducible. Based on this, we aimed to determine if echo-Doppler derived PVR (PVRecho), Cn and peak systolic tricuspid annular velocity (Sa) as parameters of RV function are relevant in predicting the cardiopulmonary exercise (CPX) capacity of patients with MS.
Methods
Study PopulationThirty-two consecutive patients (25 females, age 52.0± 9.4 years) with moderate or severe MS (mitral valve area (MVA) by 2-dimensional (2D) planimetry: 0.7-1.5 cm 2 ) were studied. Exclusion criteria included patients with left ventricular (LV) systolic dysfunction (ejection fraction (EF) <50%), mitral regurgitation more than grade I, history of underlyng ischemic heart disease or exercise-induced ST segment change on 12-lead electrocardiogram (ECG) suggeting myocardial ischemia, valvular heart disease other 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 ResultsThirty-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=0.43...