MITRAL A VELOCITY WAVE TRANSIT-TIME TO THE OUTFLOW TRACT AS A MEASUREOF LEFT-VENTRICULAR DIASTOLIC STIFFNESS - HEMODYNAMIC CORRELATIONS INPATIENTS WITH CORONARY-ARTERY DISEASE

Background Subjects in sinus rhythm have two distinct diastolic flow v elocities in the left ventricular (LV) outflow tract directed toward t he aortic valve. These follow E and A waves of the transmitral flow an d are referred to as Er and Ar waves, respectively. The A wave transit time from the mitral valve to the LV outflow tract is shorter than th at of the E wave and is shorter in those with LV hypertrophy and the a ged, suggesting its possible dependence on LV late diastolic stiffness . Methods and Results We measured the peak-to-peak and onset-to-onset A wave transit times from the mitral valve to the LV outflow tract (AA r(p) and AAr(o) intervals, respectively) using Doppler echocardiograph y in 20 patients undergoing left heart catheterization for evaluation of coronary artery disease. These intervals were correlated with indic es of LV late diastolic stiffness obtained from high-fidelity LV press ure tracings and angiographic volume assessments. The AAr(p) and AAr(o ) intervals correlated significantly with LV Dp/DV (conventionally dP/ dV) (r=-.68 and -.83, respectively), volume stiffness, V Dp/DV (r=-.74 and -.80, respectively) and LV (V/P) (Dp/DV) (r=-.69 and -.74, respec tively). The AAr(o) interval correlated better with the square roots o f LV Dp/DV and volume stiffness (r=-.86 and -.87, respectively). Concl usions We conclude that AAr(p) and AAr(o) intervals are easily obtaina ble Doppler parameters that reflect LV late diastolic stiffness in pat ients with coronary artery disease and possibly in other patient group s.