[Diagnostic value and safety of dobutamine echocardiography in the diagnosis of coronary disease]. / Valore diagnostico e sicurezza del test eco-dobutamina nella diagnosi di coronaropatia.

To assess the safety and diagnostic value of dobutamine stress-echocardiography (DSE), we studied 109 patients with ischemic heart disease: 78 patients with recent myocardial infarction, 31 patients with chest pain (14 patients without and 17 patients with previous myocardial infarction). Echocardiograms were recorded during dobutamine infusion in 5-minute stages to a maximum dose of 40 mcg/kg/min. The test was considered positive when dobutamine infusion induced a new wall motion abnormality. In 95 pts with recent or previous myocardial infarction new asynergies were classified as being within the infarct zone or outside the infarct zone based on the relation with vascular zones at coronary angiography. All patients underwent exercise stress test (EST) according to the Bruce protocol, and coronary angiography within one week from the test: significant coronary artery disease was defined as > or = 50% diameter stenosis for left main artery and > or = 70% for the other vessels. Five patients (4.6%) had ventricular arrhythmias and 3 patients (2.7%) had systolic blood pressure increase > or = 200 mm Hg in the first stage of DSE, without new wall motion abnormalities, and were excluded from diagnostic value analysis. DSE had a sensitivity of 86% vs 56% of EST (p < 0.001); both had specificity of 94% and positive prognostic value of 98%; diagnostic accuracy of DSE was 87% vs 62% of EST (p < 0.001); negative predictive value was not statistically different. Sensitivity of DSE in single vessel disease (78%) was significantly lower (p < 0.05) than sensitivity in multivessel disease (95%). Sensitivity of DSE in detecting multivessel disease in patients with myocardial infarction was 80% vs 55% of EST (p < 0.05); specificity 96% vs 63% (p < 0.001); diagnostic accuracy 90% vs 60% (p < 0.001); positive predictive value 93% vs 48% (p < 0.001); negative predictive value 89% vs 70% (p < 0.05). At the ischemic threshold, EST caused the achievement of higher heart rate and rate-pressure product; in patients with single vessel disease heart rate was higher than in multivessel disease (141 +/- 19 vs 117 +/- 21, p < 0.001). No differences were detected during DSE in heart rate, blood pressure, rate-pressure product; the dose of dobutamine infused at the ischemic threshold in patients with multivessel disease was significantly lower than in those with single vessel disease (15.2 +/- 5.4 vs 19.4 +/- 6 mcg/kg/min, p < 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)