Beta‐blocker infusion did not improve left ventricular diastolic function in myocardial infarction: A doppler echocardiography and cardiac catheterization study

Left ventricular (LV) diastolic function changes after myocardial infarction. It has been suggested that beta blockers may improve diastolic function in hypertensive and heart failure patients. Doppler echocardiographic filling patterns and invasive hemodynamic indices have been used to analyze LV diastolic function. To determine the effect of beta blockers on LV diastolic function, we studied 32 patients with anterior wall myocardial infarction with a mean age of 53 years. Peak early and late flow velocities, peak early‐to‐late flow velocities ratio, pressure half time, diastolic filling period, isovolumic relaxation time, cardiac index, mean arterial pressure, wedge pressure, and systemic and pulmonary vascular resistance indices were obtained simultaneously before and after an intravenous infusion of 10 mg of atenolol. Cardiac index decreased from 4.27 ± 0.97 to 3.19 ± 0.911/min/m 2 (p=0.0001); mean arterial pressure decreased from 85 ± 10 to 80 ± 11 mmHg (p=0.004); wedge pressure increased from 11 ± 5 to 13 ± 4 rnmHg (p = 0.002); systemic vascular resistance index increased from 1586 ± 409 to 1980 ± 634 dynm 2 s/cm 5 (p = 0.0002); pulmonary vascular resistance index increased from 115 ± 58 to 163 ± 72 dynm 2 s/cm 5 (p = 0.0004); peak late flow velocity decreased from 64 ± 15 to 49 ± 14 cm/s (p = 0.0001); early‐to‐late ratio increased from 0.95 ± 0.35 to 1.29 ± 0.36 (p = 0.0001); diastolic filling period increased from 300 ± 108 to 400 ± 110 ms (p=0.0001) and isovolumic relaxation time increased from 133 ± 29 to 143 ± 29 ms (p = 0.009). No significant changes were observed for peak early flow velocity and pressure half‐time. Multivariate regression analysis suggests that significant changes observed on Doppler echocardiographic parameters can be attributed in part to beta‐blocker effect on heart rate analyzed as diastolic filling period. We concluded that beta‐blocker infusion changes LV diastolic function analyzed by Doppler echocardiography in patients with anterior wall myocardial infarction. Moreover, the increase observed on wedge pressure suggests deterioration in cardiac function.