RESUMO
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 +/- 0.91 l/min/m2 (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 mmHg (p = 0.002); systemic vascular resistance index increased from 1586 +/- 409 to 1980 +/- 634 dyn.m2.s/cm5 (p = 0.0002); pulmonary vascular resistance index increased from 115 +/- 58 to 163 +/- 72 dyn.m2.s/cm5 (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.(ABSTRACT TRUNCATED AT 250 WORDS)
