STRESS-INDUCED LEFT-VENTRICULAR DYSFUNCTION IN SILENT AND SYMPTOMATICMYOCARDIAL-ISCHEMIA DURING DOBUTAMINE STRESS TEST

The extent and severity of dobutamine-induced left ventricular (LV) dy sfunction with and without angina were evaluated in 105 consecutive pa tients with significant coronary artery disease and a positive dobutam ine stress echocardiographic test, defined as new or worsening wall mo tion abnormalities during high-dose dobutamine stress (up to 40 mu g/k g/min). Wall motion score (WMS) was derived using a 16-segment, 4-grad e scoring method. The difference between stress and rest WMS (Delta WM S) was derived as a global measure of stress-induced LV dysfunction. T ypical angina occurred in 61 patients (58%) during the test. There was no significant difference between patients with or without angina wit h respect to age, gender, prevalence of previous myocardial infarction , multivessel disease, or number of diseased coronary arteries. Patien ts with angina had a higher prevalence of a history of angina before t he test, Rest, stress, and Delta WMS, number and distribution of ische mic segments, and number of segments with an increase in regional WMS of greater than or equal to 2 were not significantly different in pati ents with or without angina. ST-segment depression was more frequent i n patients with angina (56% vs 29%, p <0.05). Patients with (vs those without) ST-segment depression had a significantly higher number of is chemic segments with normal baseline contraction, an equal total numbe r of ischemic segments, and a similar Delta WMS. It is concluded that in patients with anatomically and functionally significant coronary ar tery disease, the amount of stress-induced LV dysfunction evaluated by dobutamine stress echocardiography is similar in patients with or wit hout angina. ST-segment depression is more common in patients with ang ina and is associated with more extensive ischemia in normally contrac ting segments at rest.