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Objective: The objective of this study was to correlate histologic changes in hibernating myocardium with dobutamine stress echocardiography (DSE)., Methods: Patients (n = 8) with anterior regional wall motion abnormalities in the seven echocardiographic segments representing the territory supplied by a significantly stenosed left anterior descending coronary artery had preoperative DSE performed (yielding 56 segments for analysis). Two transmural biopsy specimens were taken from the anterior wall of the left ventricle during coronary artery bypass grafting., Results: Morphometric histologic analysis of biopsy specimens showed significantly less fibrosis in segments demonstrating inotropic reserve (p < 0.05) and significantly less fibrosis in segments demonstrating improvement in wall motion on echocardiography 3 months after revascularization (p < 0.05). DSE had a sensitivity of 100% and a specificity of 62% for detection of hibernating myocardial segments. Percent fibrosis was inversely correlated with percent nucleated cells (r = 0.66, p < 0.01) and directly correlated with cytoplasmic clearance (r = 0.76, p < 0.01)., Conclusion: Inotropic response during DSE correlates with histologic evidence of hibernating myocardium.

Purpose: We assessed the value of dobutamine stress echocardiography for the detection of coronary artery disease in patients with chest pain and an abnormal resting electrocardiograph (ECG)., Methods: Dobutamine stress echocardiography was performed in a standard fashion. Significant coronary artery disease was defined as a >50% luminal diameter stenosis on coronary angiography., Results: The sensitivity, specificity, positive and negative predictive value of dobutamine stress echocardiography for the detection of coronary artery disease in 218 patients were 89, 50, 95 and 32%, respectively. The sensitivity for detection of multi-, double- and single vessel disease were 97, 82 and 81%, respectively. The sensitivity for the detection of coronary artery disease in a subgroup of 69 patients by treadmill exercise testing was 37%., Conclusion: Dobutamine stress echocardiography is better than exercise ECG for the detection of significant coronary artery disease. The negative predictive value of dobutamine stress echocardiography in this patient group is low.

Patients with Type 1 diabetes mellitus have an increased risk of ischaemic heart disease (IHD). When diabetes is complicated by nephropathy this risk is further increased and asymptomatic IHD is common. New techniques for non-invasive cardiac evaluation are now available and one of these, Dobutamine Stress Echocardiography (DSE), was studied in subjects with Type 1 DM and nephropathy who had no evidence of IHD. DSE was performed on 18 subjects (13 male, 5 female; mean age 37.8 +/- 3.4 years), diabetes duration 23.7 +/- 1.2 years and nephropathy diagnosed for 10.9 +/- 1.3 years. There were 7 (38%) positive scans-suggesting asymptomatic IHD; 16.7% of subjects studied had a significant arrhythmia. Coronary angiography was performed in 6 of the 7 subjects with positive DSEs and was positive in only 2. These results suggest that DSE has a high rate of false positive results in Type 1 DM patients suffering from nephropathy and may limit its usefulness in these subjects.

Background: Critical analysis of treadmill exercise testing (TMET) for the detection of coronary artery disease has revealed many shortcomings. Excellent diagnostic accuracy has been reported for dobutamine stress echocardiography (DSE)., Methods: A prospective comparison of DSE and TMET for the detection of coronary artery disease in routine clinical practice was performed using contrast cineangiography (significant stenosis > or = 50%) as a gold standard., Results: A total of 116 patients (82 men, 34 women) were studied. Significant stenosis was detected by coronary angiography in 92 patients (79%). Single vessel disease occurred in 28, double-vessel disease in 32, and multivessel disease in 32 patients. Although sensitivity of DSE was better than that of TMET (82 versus 40%), specificity was worse (63 versus 79%). Positive predictive values for both DSE and TMET were good at 89 and 87%, respectively, whereas negative predictive values were poor for both (47% for DSE, 26% for TMET)., Conclusions: Overall, DSE performs better than TMET in terms of sensitivity and positive and negative predictive value. Its lower specificity than that of TMET may lead to more patients being referred for diagnostic coronary angiography. The poor negative predictive value of DSE and TMET means that one should not be falsely reassured by normal results.

Unlabelled: In this prospective study, patients referred for coronary angiography for detection of disease underwent dobutamine stress echocardiography to define its value in a clinical practice setting., Results: Of 219 patients studied, 170 (78%) had significant coronary artery disease. The overall sensitivity and specificity of dobutamine stress echocardiography for coronary artery disease were 82 and 65%, respectively. The sensitivity was 88% for detection of triple-vessel disease, 83% for double-vessel disease, and 74% for single-vessel disease. Positive and negative predictive values for coronary artery disease were 89 and 51%, respectively. Dobutamine stress echocardiography correctly identified only 72 of 138 patients with significant stenosis of the left anterior descending coronary artery. In 219 patients, 345 of 657 major epicardial vessels had significant disease. Dobutamine stress echocardiography could only correctly identify the vessel involved in 188. Triple-vessel disease was present in 65 patients. Dobutamine stress echocardiography correctly categorised 18% (n = 12) of these. The remainder were incorrectly classified as having double-vessel disease or single-vessel disease (n = 45), or no disease at all (n = 8)., Conclusion: Dobutamine stress echocardiography performs well. However, lower specificity may lead to unwarranted referrals for coronary angiography, and the low NPV give false reassurance as to the absence of disease.

Although the accuracy of dobutamine stress echocardiography for the detection of coronary artery disease in a high-risk population is known, it has not been well defined for lower risk groups. Two probability groups, high (>75%; n = 199) and intermediate (>10% but < or =75%; n = 118), were studied. Dobutamine stress echocardiography was performed in a standard fashion. Significant coronary artery disease was defined as a >50% luminal diameter stenosis on coronary angiography. The positive predictive accuracy of dobutamine stress echocardiography for the detection of coronary artery disease was greater in the high-probability group (96% vs 86%), as was the sensitivity (89% vs 78%), whereas the negative predictive value was greater in the intermediate-probability group (50% vs 23%), as was the specificity (63% vs 50%). Dobutamine stress echocardiography does have a diagnostic role in the evaluation of patients with an intermediate probability of coronary artery disease.

Background: With expanding applications and increasingly aggressive stress protocols, concerns about the safety of dobutamine stress echocardiography (DSE) have arisen. The purpose of this study was to analyse prospectively the safety, adverse event profile and complication rate of DSE., Methods: Prospective data were recorded in a consecutive series of 474 patients undergoing DSE. Dobutamine was administered intravenously in graded infusion, each stage over 3 min, at 10, 20, 40 and, if required, 50 micrograms/kg/min. Atropine (1 mg) was administered thereafter if the response remained suboptimal., Results: The mean dose of dobutamine was 42 micrograms/kg/min, with 111 patients (23%) receiving 50 micrograms/kg/min. Atropine was required for 27 patients (6%). No patient died or suffered a myocardial infarction. Sustained ventricular tachycardia occurred in one patient, angina pectoris in 127 (27%), non-sustained ventricular tachycardia in eight (2%) and supraventricular tachycardia in 19 (4%). Profound bradycardia requiring cessation of the test occurred in one patient. Pulmonary oedema developed in one patient. A hypotensive response requiring cessation of the test was seen in one patient. Test termination because the patient complained of nausea, tremor or headache was not required., Conclusion: DSE is safe. Side effects are rare and when they occur, are usually minor. Ischaemic pain is effectively treated by termination of the test and sublingual administration of nitrates.

Background: There is a high prevalence of coronary artery disease (CAD) in patients with diabetes mellitus. Detection of inducible ischaemia using treadmill exercise testing may be limited by the relatively poor inherent predictive accuracy of the test. The purpose of this study was to determine the value of dobutamine stress echocardiography (DSE) for the detection of CAD in patients with diabetes mellitus., Methods: Patients with diabetes mellitus referred for cardiac assessment were considered eligible for study. DSE was performed in a standard fashion. Significant CAD was defined as a > 50% luminal diameter stenosis on coronary angiography., Results: A total of 52 patients (mean age 59 years) with diabetes mellitus were studied prospectively using DSE. Risk factors for CAD included hypertension in 19, family history in 21, hypercholesterolaemia in 14, history of smoking in 38. The sensitivity, specificity, positive and negative predictive values of DSE for detection of CAD were 82, 54, 84 and 50% respectively., Conclusion: The specificity of DSE for CAD in patients with diabetes mellitus is low. Whether this reflects an underdetection of small vessel disease by contrast coronary angiography or whether it relates to test performance is unclear.

The technology of transesophageal echocardiography is now widely available and has proved extremely useful in evaluating cardiovascular anatomy and pathology. Unfortunately, the enhanced echocardiographic detail and multiple transesophageal imaging planes may sometimes be confusing and cause misinterpretations. The majority of these problems are simply the result of operator inexperience. To help prevent misdiagnoses, we have collected a series of the more common diagnostic and technical "pitfalls" of transesophageal echocardiography.