Dobutamine stress--Doppler echocardiography before and after coronary angioplasty.

Abstract

To determine if dobutamine-induced myocardial ischaemia causes abnormalities in Doppler parameters of left ventricular ejection and filling and to assess early effects of successful coronary angioplasty (PTCA) on these parameters, dobutamine stress echocardiography and Doppler studies were performed once in 11 normal volunteers and twice in 17 patients (within 1 day pre- and post-PTCA). Dobutamine induced wall motion abnormalities, ST changes and angina in 11, five and five patients, respectively, before and three, two and one patients, respectively, after PTCA. Doppler indices of both systolic and diastolic function were comparable at rest, before and after PTCA. Dobutamine induced similar increases in peak aortic velocity and average acceleration in healthy individuals (39% and 53%) and in patients with one-vessel disease both before (38% and 39%) and after PTCA (39% and 40%). In the three patients with multivessel disease, peak aortic velocity showed a blunted response (-0.3%) before PTCA but increased by 17% after PTCA, while acceleration decreased both before (12%) and after PTCA (14%). There were significant differences (P < 0.0001) between healthy individuals and pre-PTCA patients in the effect of dobutamine on peak early (E) filling velocity (+34% vs -19%), E-acceleration (+35% vs -26%), peak early to atrial filling velocity ratio (E/A) (-0.7% vs -37%) and diastolic time velocity integral (TVI) (+34% vs -22%). After PTCA, the response of Doppler diastolic indices improved during dobutamine, as shown by the increase in E and E-acceleration (+8%, +24%), respectively) and by the decline in the reduction of E/A and TVI (-17% and -10%, respectively). Thus, the response of Doppler diastolic parameters to dobutamine stress is a sensitive indicator of significant coronary disease and is superior to changes in ejection indices. Successful PTCA resulted in an improved diastolic filling response to dobutamine stress.