Associations of increased arterial stiffness with left ventricular ejection performance and right ventricular systolic pressure in mitral regurgitation before and after surgery: Wave intensity analysis

BACKGROUND The effect of increased arterial stiffness on mitral regurgitation (MR) is not clear. Using wave intensity (WI) analysis, which is useful for analyzing ventriculo-arterial interaction, we aimed to elucidate associations of increased arterial stiffness with left ventricular (LV) ejection performance and right ventricular systolic pressure (RVSP) in MR. METHODS AND RESULTS We noninvasively measured carotid arterial WI and stiffness parameter (β) in 98 patients with non-ischemic chronic MR before and after surgery, and 98 age-and-gender matched healthy subjects by ultrasonography. WI is defined as WI = (dP/dt)(dU/dt) [P: blood pressure, U: velocity, t: time]. The peak value of WI (W1) increases with LV peak dP/dt. The temporal WI index (Q-W1)st, which is the standardized interval between the Q wave of the ECG and W1, is a surrogate for preejection period. Ejection fraction (EF), left atrial volume index (LAVI), effective regurgitant orifice area (ERO), RVSP, and other echocardiographic data were also obtained. W1 was enhanced in the MR group before surgery compared with the normal group (10.7 ± 5.7 vs 8.5 ± 3.6 × 103 mmHg m/s3, p < 0.05). However, the results of two-way ANOVA showed this enhancement of W1 was observed only in the subgroup of MR before surgery with lower arterial stiffness (β < 13, p< 0.0001). ERO, β and LAVI were predictor variables before surgery to determine RVSP. EF and (Q-W1)st before surgery were predictor variables for EF after surgery. CONCLUSIONS In the MR group before surgery, increased arterial stiffness suppresses compensatory enhancement of W1, and increases RVSP. Prolonged (Q-W1)st has the potential for predicting low EF after surgery.