Dobutamine Echocardiography In Patients Research Articles

Limitations of dobutamine echocardiography in patients with significant left ventricular dysfunction

Limitations of dobutamine echocardiography in patients with significant left ventricular dysfunction

Long-Term Prognostic Significance of Dobutamine Echocardiography in Patients With Suspected Coronary Artery Disease: Results of a 5-Year Follow-Up Study

Objectives. This study sought to assess the long-term prognostic utility of dobutamine stress echocardiography in predicting fatal and nonfatal cardiac events.Background. Although dobutamine stress echocardiography has improved sensitivity and specificity for detection of coronary artery disease, little is known of its predictive value for long-term cardiac events. Therefore, we followed up 120 consecutive patients who underwent dobutamine echocardiography for suspected coronary disease from March 1989 to August 1991.Methods. All patients presenting for coronary angiography for chest pain were eligible for recruitment. Follow-up was 100% complete at 5 years (range 3.0 to 6.1). Cardiac events were defined as cardiac death or nonfatal myocardial infarction or the need for coronary revascularization (coronary angioplasty or bypass surgery).Results. Positive (n = 78) and negative (n = 42) dobutamine test groups differed in their rates of coronary artery bypass graft surgery (37.2% vs. 9.5%, p < 0.001, respectively) and mortality. Of 26 total deaths, 22 occurred in the group with positive dobutamine test results (28% vs. 9.5%, p < 0.018); all 7 cardiac deaths occurred in this group as well (9% vs. 0%, p < 0.045). By multivariate regression analysis, positive results on dobutamine echocardiography remained independently predictive of future cardiac death after left ventricular ejection fraction and other clinical variables were accounted for.Conclusions. A positive finding on dobutamine echocardiography is an independent predictor of long-term cardiac mortality, whereas a negative finding confers a significantly reduced likelihood of cardiac death as much as 5 years from initial testing. We conclude that dobutamine stress echocardiography can be used to predict which patients with suspected coronary artery disease are at low risk for cardiac death and do not require concurrent nuclear or invasive testing.(J Am Coll Cardiol 1997;29:969–73)© 1997 by the American College of Cardiology

Relation between ST segment elevation during dobutamine stress test and myocardial viability after a recent myocardial infarction.

OBJECTIVE: To assess the relation between ST segment elevation during the dobutamine stress test and late improvement of function after acute Q wave myocardial infarction. PATIENTS AND DESIGN: 70 patients...

Comparison of ischemic response during exercise and dobutamine echocardiography in patients with left main coronary artery disease

This study sought to compare manifestations of myocardial ischemia evoked by exercise and dobutamine echocardiography in patients with left main coronary artery disease. During exercise testing, left ventricular cavity dilation, marked ST segment depression and blood pressure decrease indicate severe coronary artery disease. Whether these signs are comparably evoked by dobutamine echocardiography has not been described. Fifty-four patients who underwent stress echocardiography (36 exercise, 18 dobutamine) and coronary angiography showing > or = 50% left main stenosis were analyzed. Electrocardiographic and blood pressure changes, symptoms, wall motion score indexes and sensitivity for coronary artery disease were compared. In 47 patients, the left ventricular endocardium was traced to quantify volumes and ejection fraction. Stress-induced regional wall motion abnormalities developed in 91% of patients; this was not different on exercise (89%) or dobutamine echocardiography (94%). Rate-pressure product and wall motion score index, similar at rest, tended to be higher after exercise than after dobutamine stress (p = 0.07 and p = 0.05, respectively). ST segment depression > or = 1 mm was more common with exercise (p = 0.005). Ejection fraction and end-systolic and end-diastolic volume indexes were comparable at rest in both groups. With exercise, ejection fraction decreased in 87% of patients, and end-systolic and end-diastolic volume indexes increased in 80%. In contrast, with dobutamine, decreased ejection fraction and increased volume indexes were infrequent. Ejection fraction was lower ([mean +/- SD] 45 +/- 19% vs. 54 +/- 12%, p = 0.007) and end-diastolic (69 +/- 26 vs. 50 +/- 17 ml/m2, p =0.02) and end-systolic (39 +/- 20 vs. 24 +/- 13 ml/m2, p = 0.02) volume indexes were higher after exercise than after dobutamine stress. On the basis of changes in regional wall motion both dobutamine and exercise echocardiography have a comparable high sensitivity in diagnosing myocardial ischemia in left main coronary artery disease. However, conventional signs of severe myocardial ischemia, including left ventricular cavity dilation and marked ST segment depression, occur more often with exercise than with dobutamine echocardiography.

Exercise versus dobutamine echocardiography in patients with chronic coronary artery disease

Exercise versus dobutamine echocardiography in patients with chronic coronary artery disease

Prognostic value of dobutamine echocardiography in patients with left ventricular dysfunction

This study sought to establish the prognostic implications of ischemic and viable myocardium identified by dobutamine echocardiography in patients with left ventricular dysfunction. Recent studies have suggested that in patients with viable myocardium identified by positron emission tomography, medical treatment is associated with recurrent cardiac events. Dobutamine echocardiography has been used to identify viable myocardium in patients with left ventricular dysfunction, but the prognostic significance of this test is undefined. One hundred thirty-six consecutive patients (mean [+/- SD] age 67 +/- 7.9 years; 104 men) with moderate or severe left ventricular dysfunction (left ventricular ejection fraction 30 +/- 5%) undergoing dobutamine echocardiography were included in the study. Dobutamine was administered using a standard incremental protocol (5 to 40 micrograms/kg body weight per min intravenously in 3-min stages) with additional atropine (1 mg intravenously) as required. Standard body weight echocardiographic views were digitized on-line and compared using a side-by-side display. Viable myocardium was identified by enhancement of regional function at low dose (< 10 micrograms); scar was diagnosed by akinesia at rest or dyskinesia without change and ischemia as new or worsening dysfunction. One hundred thirty patients (95%) were followed up for 16 +/- 8 months after the original study for major cardiac events (cardiac death, myocardial infarction or severe unstable angina requiring late myocardial revascularization). No significant complications occurred during dobutamine echocardiography. Viable myocardium was detected in 26 patients (19%), ischemia in 23 (17%), both viability and ischemia in 13 (10%) and scar in 74 (54%). Of 108 patients treated medically, 46 had viable or ischemic myocardium, and 62 had scar only. There were no significant differences in age or other clinical characteristics, stress response, left ventricular dimensions and ejection fraction between the two groups. Cardiac events occurred in 26 medically treated patients (24%): 18 died of cardiac-related causes; 4 had a nonfatal myocardial infarction; and 4 had late revascularization because of unstable angina. The event rate was greater in patients with viable or ischemic myocardium than those with scar (43% vs. 8%, p = 0.01 by log-rank test). In a Cox regression model, the presence of viable or ischemic myocardium was found to predict subsequent events (relative risk 3.51, p = 0.02) independently of ejection fraction and age. Viable or ischemic myocardium detected at dobutamine echocardiography in patients with left ventricular dysfunction is associated with an adverse prognosis, independent of age and ejection fraction.

Enhanced detection of myocardial ischemia by stress dobutamine echocardiography utilizing the “biphasic” response of wall thickening during low and high dose dobutamine infusion

We sought to assess the ability of the "biphasic" response (i.e., initial improvement in wall thickening followed by reduced wall thickening) during serial dobutamine stress echocardiography to detect ischemia in patients with a wall motion abnormality. Furthermore, we compared the power of the biphasic echocardiographic response with that of myocardial perfusion imaging for the detection of myocardial ischemia. Stress echocardiography has been shown to be less sensitive than radionuclide perfusion imaging for detecting ischemia in patients with a wall motion abnormality. Peak stress wall thickening in such areas may not give a full account of the intermediate changes, whereas initial improvement (the biphasic response) may enhance diagnosis. Patients with a wall motion abnormality and documented coronary artery disease underwent simultaneous graded dobutamine (5 to 40 micrograms/kg body weight per min) stress echocardiography and radionuclide perfusion imaging with single-photon emission computed tomography using either technetium-99m sestamibi or technetium-99m tetrofosmin. Semiquantitative analyses of image groups were performed in blinded manner by two separate groups of observers. Myocardial ischemia was detected by perfusion imaging in 45 of the 54 patients. High dose dobutamine echocardiography detected ischemia in only 25 (56%) of these patients. However, when the biphasic response was taken into account, ischemia was detected in 44 (98%) of the 45 patients (p < 0.001). Agreement between radionuclide imaging and echocardiographic findings for the detection of ischemia was significantly enhanced (p = 0.03) when the biphasic response was used (89%, kappa = 0.51) instead of high dose stress dobutamine echocardiography (56%, kappa = 0.10). The detection of myocardial ischemia may be significantly enhanced by utilizing the biphasic response during serial stress dobutamine echocardiography in patients with a wall motion abnormality.

Prognostic Value of Dobutamine Echocardiography in Patients with High Pretest Likelihood of Coronary Artery Disease

Prognostic Value of Dobutamine Echocardiography in Patients with High Pretest Likelihood of Coronary Artery Disease

Prognostic value of dobutamine echocardiography in patients with high pretest likelihood of coronary artery disease

To examine the value of transient regional asynergy on dobutamine stress echocardiography as a noninvasive predictor of future cardiac events, 51 symptomatic patients (aged 54 ± 9 years) with suspected coronary artery disease (CAD) were studied using an incremental regimen of 5, 10, 15 and 20 μg/kg/min. Pretest likelihood of CAD was (mean ± standard error of the percentage) 79.7 ± 5.6% before and 83.4 ± 5.2% after exercise electrocardiography using probability analysis based on age, sex and symptoms. Two-dimensional images were analyzed with reference to an 11-segment model and gave good interrater agreement. During 24 ± 4 months (range 19 to 32) of follow-up, 23 patients had events (1 myocardial infarction, 9 unstable angina, 10 coronary bypass surgery, 3 coronary angioplasty) and 28 were event free. Age, proportion with baseline asynergy and both pretest echocardiographic ejection fraction and its response to dobutamine were similar in these 2 groups (all p = not significant). Transient asynergy was seen in 17 of 23 patients (74%) with and 8 of 28 patients (29%) without events (p < 0.01); 5 of 6 patients (83%) with involvement of 3 segments had events. Myocardial infarction or unstable angina occurred in 8 of 25 (32%) with a positive and 2 of 26 (8%) with a negative stress echocardiogram (p < 0.05). Both exercise duration (389 ± 195 vs 517 ± 237 seconds, p < 0.05) and time to diagnostic ST-segment shift (291 ± 192 vs 447 ± 212 seconds, p = 0.05) were shorter in those with inducible asynergy. These data suggest that patients with probable CAD and a positive dobutamine echocardiogram are at higher risk of an adverse outcome. Dobutamine echocardiography may aid selection for coronary angiography and prognostic revascularization, particularly in patients unable to exercise.