EVOLUTION OF DOBUTAMINE ECHOCARDIOGRAPHY PROTOCOLS AND INDICATIONS - SAFETY AND SIDE-EFFECTS IN 3,011 STUDIES OVER 5 YEARS

Objectives. This study sought to document the safety of debutamine str ess echocardiography as it has evolved at a single center and to defin e predictors of adverse events. Background The indications and protoco l for dobutamine stress testing have evolved over 5 years of clinical use, but the influence of these changes on the safety and side effects of the test is undefined. Methods. Over 5 years, 3,011 consecutive do butamine stress studies were performed in 2,871 patients, using an inc remental protocol from 5 to 40 mu g/kg body weight per min in 3-min st ages, followed by atropine or an additional stage with 50 mu g/kg per min, if required. Clinical data were gathered prospectively, and hemod ynamic and echocardiographic findings were recorded at each stage, inc luding recovery. Dobutamine echocardiography was defined as positive f or ischemia in the presence of new or worsening wall motion abnormalit ies; in the absence of ischemia, failure to attain 85% of age-predicte d maximal heart rate was identified as a nondiagnostic result. Results . Studies were performed for risk assessment (70%) and symptom evaluat ion (30%); over the study period, there was an increment in the use of dobutamine echocardiography for preoperative evaluation. Most tests ( n = 2,194 [73%]) were terminated due to attainment of peak dose,vith a chievement of target heart rate (>85% maximal age predicted heart rate ); 455 patients (15%) failed to achieve >85% maximal predicted heart r ate despite maximal doses of dobutamine and atropine. The protocol was stopped prematurely in 230 patients (7.6%) because of side effects, i ncluding ventricular (n = 27 [0.9%]) and supraventricular rhythm disor ders (n = 22 [0.7%]), severe hypertension (n = 24 [0.8%]) and hypotens ion or left ventricular outflow tract obstruction (n = 112 [3.8%]). No ncardiac symptoms, such as headache, nausea or anxiety, caused early t est termination in 45 patients (1.6%). The remaining test were stopped because of severe chest pain (n = 106 [3.5%]) or severe ischemia by e chocardiography (n = 26 [0.9%]). Serious complications occurred in nin e patients, including sustained ventricular tachycardia in five, myoca rdial infarction in one and other conditions in three requiring hospit al admission (sustained supraventricular tachycardia, hypotension, sus pected myocardial infarction), but neither ventricular fibrillation no r death occurred. Independent predictors of serious complications coul d not be defined. Over 5 years, higher dose protocols and more frequen t use of atropine have raised the number of diagnostic protocols from 59% to 80%, without increasing the incidence of major side effects. Co nclusions. Despite the use of more aggressive protocols and alteration s of the indications for testing to include sicker patients, major sid e effects are a rare complication of dobutamine echocardiography. (C) 1997 by the American College of Cardiology.