Dipyridamole and dobutamine-atropine stress echocardiography in the diagnosis of coronary artery disease. Comparison with exercise stress test, analysis of agreement, and impact of antianginal treatment

STUDY OBJECTIVES: To compare the usefulness of dipyridamole echocardiography, dobutamine-atropine echocardiography, and exercise stress testing in the diagnosis of coronary artery disease and to analyze the agreement among the tests. DESIGN: Performance of these three tests in random order on a consecutive cohort of patients. SETTING: A tertiary care and university center. PATIENTS: One hundred two consecutive patients with chest pain and no history of coronary artery disease. INTERVENTIONS: Dipyridamole echocardiography, dobutamine-atropine echocardiography, exercise stress testing, and coronary angiography. MEASUREMENTS AND RESULTS: Dobutamine-atropine test was positive in 49 (77%) of 63 patients with coronary artery disease, dipyridamole test in 49 (77%), and exercise stress test in 44 (68%; p = NS). Both echocardiographic tests showed an overall specificity (dipyridamole, 97%; dobutamine, 95%) higher than exercise stress test (79%; p < 0.05). Sensitivity of dipyridamole testing decreased from 93 to 61% (p = 0.002) if patients were receiving antianginal treatment but sensitivity of dobutamine-atropine testing was not affected (77% in patients receiving and not receiving treatment). When results were considered as positive-negative, agreement between dipyridamole and dobutamine-atropine echocardiography was 85% (kappa = 0.70). With regards to regional analysis, concordance was good (93% for segments, kappa = 0.76; and 95% for coronary arteries, kappa = 0.92). Major complications were more frequent during dobutamine-atropine (n = 7) than during dipyridamole infusion (n = 2) (p = 0.06). CONCLUSIONS: Dobutamine-atropine and dipyridamole echocardiography have a similar sensitivity and a higher specificity than that obtained by exercise ECG for the diagnosis of coronary artery disease. Similar information is obtained with dipyridamole and dobutamine-atropine echocardiography. It is our thought that pharmacologic stress echocardiography should be used as a first-step test to rule out coronary artery disease in patients not capable of exercising.     

Echocardiography with dobutamine in hypertensive patients with chest pain

INTRODUCTION: The exercise stress test shows limited diagnostic accuracy for the detection of coronary artery disease in hypertensive patients. Echocardiography with dobutamine is a useful tool in the assessment of coronary artery disease. PURPOSE: Our purpose has been to compare dobutamine stress echocardiography and exercise stress test for diagnosing coronary disease in hypertensive patients. MATERIAL AND METHODS: Dobutamine stress echocardiography (administered up to 40 micrograms/kg/min, and atropine when necessary), exercise stress test and coronary arteriography were performed on 74 hypertensive patients with chest pain and no previous history of coronary artery disease. RESULTS: Forty-eight (65%) patients underwent a diagnostic exercise stress test and 66 (89%) a diagnostic dobutamine stress echocardiography. Coronary artery disease (> or = 70% stenosis in, at least, one major vessel) was demonstrated in 28 (58%) patients who underwent a diagnostic exercise stress test, and in 39 (59%) patients who completed a dobutamine stress echocardiography. Sensitivity for exercise stress test was 82%, and 79% for dobutamine stress echocardiography (p = NS). Specificity was higher for dobutamine stress echocardiography (100% vs 60%; p < 0.005). CONCLUSIONS: Dobutamine stress echocardiography has high sensitivity and specificity for the detection of coronary artery disease in hypertensive patients. Dobutamine stress echocardiography has higher feasibility and specificity than exercise stress test in this group of patients.     

Noninvasive diagnosis of ischemia-induced wall motion abnormalities with the use of high-dose dobutamine stress MRI: comparison with dobutamine stress echocardiography

BACKGROUND: The analysis of wall motion abnormalities with dobutamine stress echocardiography (DSE) is an established method for the detection of myocardial ischemia. With ultrafast magnetic resonance tomography, identical stress protocols as used for echocardiography can be applied. METHODS AND RESULTS: In 208 consecutive patients (147 men, 61 women) with suspected coronary artery disease, DSE with harmonic imaging and dobutamine stress magnetic resonance (DSMR) (1.5 T) were performed before cardiac catheterization. DSMR images were acquired during short breath-holds in 3 short-axis views and a 4- and a 2-chamber view (gradient echo technique). Patients were examined at rest and during a standard dobutamine-atropine scheme until submaximal heart rate was reached. Regional wall motion was assessed in a 16-segment model. Significant coronary heart disease was defined as >/=50% diameter stenosis. Eighteen patients could not be examined by DSMR (claustrophobia 11 and adipositas 6) and 18 patients by DSE (poor image quality). Four patients did not reach target heart rate. In 107 patients, coronary artery disease was found. With DSMR, sensitivity was increased from 74.3% to 86.2% and specificity from 69.8% to 85.7% (both P<0.05) compared with DSE. Analysis for women yielded similar results. CONCLUSIONS: High-dose dobutamine magnetic resonance tomography can be performed with a standard dobutamine/atropine stress protocol. Detection of wall motion abnormalities by DSMR yields a significantly higher diagnostic accuracy in comparison to DSE.     

Ultrasonic tissue characterization in predicting residual ischemia and myocardial viability for patients with acute myocardial infarction

The identification of viable myocardium and residual ischemia in patients with acute myocardial infarction has important prognostic implications. The ultrasonic tissue characterization with integrated backscatter and dobutamine-atropine stress echocardiography were performed 8.3+/-3 days after AMI in 30 patients. After coronary angioplasty for the residual stenosis of infarct-related artery, both modalities were repeated. The parameter obtained from ultrasonic tissue characterization, phase-weighted variation, could differentiate the myocardium with residual coronary stenosis or nonviable myocardium from the viable myocardium without residual coronary stenosis (p < 0.001). Using the cutoff value of 5.8 dB, the sensitivity, specificity and accuracy for detecting viable myocardium without residual coronary stenosis were 75%, 100% and 90.2%, respectively. The phase-weighted variation of the viable infarction zone restored after the coronary stenosis was relieved. In contrast, the nonviable myocardium had a small phase-weighted variation that was irrelevant to the patency of the infarct-related artery. The ultrasonic tissue characterization may be used in identifying patients with acute myocardial infarction whose infarction zones are viable without residual ischemia.     

Dobutamine stress echocardiography: clinical utility and predictive value at various infusion rates

Dobutamine stress echocardiography has increasingly been used to assess patients for coronary artery disease. Despite the popularity of this test, the optimal dose of dobutamine has not been established. The objective of this study was to assess the accuracy of dobutamine stress echocardiography at various infusion doses and its utility as a predictor of perioperative risk in patients undergoing a noncardiac surgical procedure. One hundred thirteen consecutive patients underwent dobutamine stress echocardiography, subsequent cardiac catheterization and/or a noncardiac surgical procedure. Three patient groups were analyzed on the basis of peak dobutamine infusion rates (17 +/- 4, 29 +/- 2, and 40 +/- 0 micrograms/kg/min, respectively). The three groups were comparable with regard to age, sex, ejection fraction, and severity of coronary artery disease. In group I, the sensitivity and specificity of dobutamine stress echocardiography were 74% and 33%, respectively, with a positive predictive value of 78%. In group II, the sensitivity and specificity improved to 84% and 78%, with a positive predictive value of 89%. In group III, the sensitivity and specificity were 86% and 80%, respectively, with a positive predictive value of 86%. In the noncardiac surgical group there was only one nonfatal cardiac complication among the 50 patients with a dobutamine echocardiogram, which was negative for evidence of inducible ischemia. In conclusion, this study demonstrates that dobutamine stress echocardiography should use an infusion rate of > or = 30 micrograms/kg/min to optimize diagnostic accuracy relative to angiographic coronary artery disease. A test that shows no evidence of new, inducible ischemia predicts a low risk of perioperative cardiac events in patients undergoing noncardiac surgery, even at an infusion rate as low as 20 microns/kg/min.     

Noninvasive diagnosis of coronary artery stenosis in women with limited exercise capacity: comparison of dobutamine stress echocardiography and 99mTc sestamibi single-photon emission CT

OBJECTIVES: To compare the accuracy of dobutamine stress echocardiography (DSE) and simultaneous 99mTc sestamibi (MIBI) single-photon emission CT (SPECT) imaging for the diagnosis of coronary artery stenosis in women. PATIENTS: Seventy women with limited exercise capacity referred for evaluation of myocardial ischemia. METHODS: DSE (up to 40 microg/kg/min) was performed in conjunction with stress MIBI SPECT. Resting MIBI images were acquired 24 h after the stress test. Ischemia was defined as new or worsened wall motion abnormalities confirmed by DSE and as reversible perfusion defects confirmed by MIBI. Significant coronary artery disease was defined as > or = 50% luminal diameter stenosis. RESULTS: DSE was positive for ischemia in 35 of 45 patients with coronary artery stenosis and in 2 of 25 patients without coronary artery stenosis (sensitivity = 78% CI, 68 to 88; specificity = 92% CI, 85 to 99; and accuracy = 83% CI, 74 to 92). A positive MIBI study for ischemia occurred in 29 patients with coronary artery stenosis and in 7 patients without coronary artery stenosis (sensitivity = 64% CI, 53 to 76; specificity = 72% CI, 61 to 83; and accuracy = 67% CI, 56 to 78 [p < 0.05 vs DSE]). In the 59 vascular regions with coronary artery stenosis, the regional sensitivity of DSE was higher than MIBI (69% CI, 62 to 77 vs 51% CI, 42 to 59, p < 0.05), whereas specificity in the 81 vascular regions without significant stenosis was similar (89% CI, 84 to 94 vs 88% CI, 82 to 93, respectively). CONCLUSION: DSE is a useful noninvasive method for the diagnosis of coronary artery stenosis in women and provides a higher overall and regional diagnostic accuracy than dobutamine MIBI SPECT in this particular population.     

Diffusion-weighted MR imaging with a single-shot echoplanar sequence: detection and characterization of focal hepatic lesions

BACKGROUND: The aim of this study was to establish the feasibility, safety, and diagnostic accuracy of the dipyridamole echocardiography test in patients with severe aortic valve stenosis for noninvasive detection of coexisting coronary artery disease. METHODS: The high-dose dipyridamole echocardiography test was performed in 52 patients with severe aortic stenosis; all patients also underwent coronary angiography, independent of test results, before cardiac operation. RESULTS: The dipyridamole echocardiography test was completed without major complications. One patient had transient atrial fibrillation that was reversed by aminophylline. Thirty-one patients (60%) had a negative test result; all had normal coronary arteries. Ten of the 21 patients (48%) with a positive test result had coexisting coronary artery disease. The positive predictive value of the dipyridamole echocardiography test for detection of coronary disease in patients with severe aortic stenosis was 48%. The negative predictive value was 100%. The sensitivity was 100% and the specificity was 74%. CONCLUSIONS: Dipyridamole echocardiography is a safe and feasible tool in patients with severe aortic stenosis eligible for a cardiac operation. A negative test result reliably rules out a significant stenosis, whereas a positive one is much less accurate in predicting coronary artery disease.     

Comparison of dobutamine stress echocardiography and treadmill exercise electrocardiography for detection of coronary artery disease

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.     

Primary rhabdomyosarcoma of the brain: observations on a case with clinical and radiological evidence of cure

BACKGROUND: After heart transplantation, accelerated coronary vasculopathy is a major factor that limits long-term survival and is usually detected by serial coronary angiography. The aim of this study was to determine whether dobutamine stress echocardiography could accurately identify the progression of cardiac allograft vasculopathy. METHODS: Two sequential controls by dobutamine stress echocardiography were performed at an 18-month interval in 37 heart transplant recipients at the time of their routine coronary angiography. The first control (control 1) occurred 37+/-20 months after transplantation, and the second control (control 2) occurred after 56+/-21 months. Standard echocardiographic views were acquired at baseline and at incremental dobutamine infusion levels. Regional wall motion score was calculated in a 16-segment model, and each segment was graded from 1 (normal) to 4 (dyskinesia). Visual and quantitative coronary angiographic analysis were used to assess the severity of the coronary vasculopathy. RESULTS: The incidence of coronary vasculopathy increased from 46% (17/37 patients, four of whom had stenoses > 50%) at control 1 fo 70% (26/37 patients, six of whom had stenoses > 50%) at control 2. Progression of coronary vasculopathy was diagnosed by coronary angiography in 25 patients (new abnormalities in 19 and worsening of previous abnormalities in 6). Dobutamine stress echocardiography correctly identified the progression of vasculopathy in 21 of these 25 patients (84%) with new abnormalities in 17 and worsening in four. In the four remaining patients with evidence of progression of vasculopathy on coronary angiography, the result of dobutamine stress echocardiography was abnormal in three patients and normal in only one. Therefore dobutamine stress echocardiography results were abnormal in 12 patients at control 1 (sensitivity: 65%, specificity: 95%) and in 27 at control 2 (92% sensitivity, 73% specificity). CONCLUSION: Dobutamine stress echocardiography is a sensitive, noninvasive method to diagnose the progression of allograft vasculopathy, and a negative test result is a strong predictor of absence of allograft coronary vasculopathy. Therefore serial routine coronary angiography may be deferred when dobutamine stress echocardiography results are normal.     

Effect of cigarette smoke on CYP1A1, CYP1A2 and CYP2B1/2 of nasal mucosae in F344 rats

BACKGROUND: Dobutamine stress echocardiography (DSE) is sensitive and specific in detecting myocardial ischemia of male patients. However, there have been few reports about the use of DSE for the detection of coronary artery disease (CAD) in women. METHODS: DSE was evaluated in 51 consecutive women who underwent concomitant quantitative coronary angiography. Forty-four of the 51 patients received stress thallium-201 single-photon emission computed tomography (SPECT), and 30 of the 51 patients had interpretable results (exercise level > or = 85% of age-predicted maximal heart rate) of treadmill exercise. Twenty-nine patients had angiographically documented CAD defined as > or = 50% diameter stenosis. RESULTS: The overall sensitivity of DSE and stress 201Tl SPECT in detecting CAD was 93% and 79% (p = nonsignificant), and the specificity was 82% and 75% (p = nonsignificant), respectively. A combination of both tests increased the sensitivity (96%) at the expense of some decrease in specificity (60%). The agreement of DSE and 201Tl SPECT was 68% (30 of 44; kappa statistic = 0.35; p < 0.0001). The overall sensitivity, specificity, and accuracy in detecting CAD by treadmill exercise test and DSE were 71% vs 93% (p = nonsignificant), 44% vs 82% (p = 0.036), and 57% vs 88% (p = 0.003). In patients with abnormal results of treadmill exercise testing, the false-positive rate in detecting CAD was 2 (18%) of 11 in patients with abnormal results of DSE and 7 (88%) of 8 in those with normal results of DSE (p = 0.005). In patients with normal results of treadmill exercise testing, the false-negative rate in detecting CAD was 4 (100%) of 4 in patients with abnormal results of DSE and 0 (0%) of 7 in those with normal results of DSE (p = 0.003). CONCLUSION: The diagnostic accuracy of DSE was similar to that of stress 201Tl SPECT in women. DSE was able to stratify female patients with either abnormal or normal results of treadmill exercise testing and to avoid unnecessary cardiac catheterization.     

Improved specificity of transesophageal dobutamine stress echocardiography compared to standard tests for evaluation of coronary artery disease in women presenting with chest pain

The detection of coronary artery disease (CAD) by noninvasive methods has been hindered in women by the high rate of false-positive results. To determine the feasibility and accuracy of transesophageal dobutamine stress echocardiography for identification of CAD in women, we studied 84 patients (age 51 +/- 11 years) who underwent symptom-limited exercise treadmill testing, exercise thallium-201 scintigraphy, and coronary angiography for evaluation of anginal chest pain. Of the 84 patients, 62 had normal coronary arteries or nonsignificant coronary lesions, and 22 had significant stenosis of > or = 1 major coronary artery. During treadmill exercise, repolarization changes were observed in 16 of 21 patients with CAD and in 19 of 60 patients with normal coronary arteries. With thallium scintigraphy, a reversible defect was observed in 19 of 22 patients with CAD and in 12 of 60 patients with normal coronary arteries. Regional wall motion abnormalities during dobutamine infusion developed in 18 of 22 patients with CAD and in none of the 62 patients with normal coronary arteries. All 3 tests had similar sensitivity for detection of CAD (76% for exercise treadmill test, 86% for thallium scintigraphy, and 82% for transesophageal dobutamine stress echocardiography). However, transesophageal dobutamine stress echocardiography had significantly higher specificity than the other 2 tests (100% vs 68% for exercise treadmill test and 80% for thallium scintigraphy; p = 0.0001). Thus, transesophageal dobutamine stress echocardiography is accurate for evaluation of CAD among women presenting with chest pain; its use should be considered when more conventional tests are equivocal or technically suboptimal.     

A recurrent nonrandom translocation (3;7)(q27;p12) associated with BCL-6 gene rearrangement in B-cell diffuse large cell lymphoma

BACKGROUND: To overcome the relatively low accuracy of exercise stress testing (EST) in detecting coronary artery disease (CAD), both echocardiography and perfusion scintigraphy have been evaluated in conjunction with pharmacologic stress, but there is still uncertainty of the relative value of these tests as possible first-line examinations for suspected CAD. This study evaluated the accuracy of EST, dipyridamole and dobutamine stress echocardiography (DIP-ECHO, DOB-ECHO), and dipyridamole and dobutamine technetium 99m sestamibi tomography (DIP-MIBI, DOB-MIBI) for the detection of CAD in patients evaluated for the first time because of chest pain. METHODS AND RESULTS: Sixty patients underwent EST, DIP-ECHO, DOB-ECHO, DIP-MIBI, and DOB-MIBI. Echocardiographic images were acquired simultaneously with sestamibi injections, and the scintigraphic images were collected 1 hour later. Coronary angiography was performed within 15 days. Out of 33 patients with significant (>70%) coronary stenoses, 19 (58%) were correctly identified by EST, 18 (55%) by DIP-ECHO, 20 (61%) by DOB-ECHO, 32 (97%) by DIP-MIBI, and 30 (91%) by DOB-MIBI (p < 0.005 for MIBI vs EST and ECHO). The specificity of EST was 67% (p < 0.05 vs ECHO and MIBI), 96%, 96%, 89%, and 81%, respectively. Of the 62 stenotic coronary arteries, 20 (32%) were correctly identified by DIP-ECHO, 24 (39%) by DOB-ECHO, 48 (77%) by DIP-MIBI, and 45 (73%) by DOB-MIBI. The sensitivity of the imaging techniques in predicting the presence of multivessel disease was 14% and 29% for DIP and DOB-ECHO compared with 48% and 57% for DIP and DOB-MIBI. CONCLUSIONS: Our results confirm the limited reliability of EST in detecting CAD and the good diagnostic value of DIP and DOB-MIBI. Conversely, the lower sensitivity and the poorer capability to recognize multivessel CAD do not support the role of either DIP or DOB-ECHO as first-line examination for suspected CAD.     

Stress echocardiography versus scintigraphy in evaluating coronary heart disease: stress echocardiography is superior

Stress echocardiography has evolved as a routinely employed non-invasive method for the evaluation of patients with coronary artery disease. The diagnostic accuracy of stress echocardiography for the detection of myocardial ischemia is comparable to scintigraphic myocardial perfusion imaging, and may even have a higher specificity for the evaluation of myocardial viability. User-friendliness including patient and investigator safety, availability and mobility of the method, and environmental compatibility, is superior to that of scintigraphy. The potential for future developments, especially in the field of digital imaging and telecommunication, is great. Last but not least, echocardiography is the method most familiar to cardiologists. The sum of these arguments renders stress echocardiography the superior method to scintigraphy in the evaluation of patients with coronary artery disease.     

Perimenstrual eruptions

PURPOSE: To study the safety and feasibility of dobutamine-atropine stress echocardiography (DASE) in patients with known or suspected coronary artery disease. METHODS: There were 3,000 DASE that were studied in a prospective fashion. All symptoms and side effects were stored in a data base format. RESULTS: Major test-related complications observed included one case of myocardial infarction, four cases of sustained ventricular tachycardia and five cases of atropine intoxication. There was no death or ventricular fibrillation as a direct or indirect consequence of the test. The infusion protocol allowed to us to examine patients using beta blockers, and led to 95% feasibility. CONCLUSION: DASE is a safe and feasible method for the study of patients with suspected or known coronary artery disease.     

Stress echocardiography. Part I. Exercise echocardiography: techniques, implementation, clinical applications, and correlations

OBJECTIVE: To describe the techniques and applications of exercise echocardiography. DESIGN: We review pertinent experimental and clinical studies from the literature and present our experience with the first 2,000 patients who underwent exercise echocardiography in our laboratory. MATERIAL AND METHODS: The indications for and contraindications to exercise echocardiography and the advantages, limitations, and accuracy of this procedure in comparison with other techniques for detecting coronary artery disease are discussed. RESULTS: Exercise echocardiography is increasingly used for the noninvasive evaluation of coronary artery disease because, in addition to its diagnostic capabilities, it offers attractive features such as portability, versatility, rapid availability of results, and relatively low cost. For accurate interpretation of the results, the workload achieved and the time between completion of exercise and image acquisition must be considered. The major limitation of exercise echocardiography is the high degree of operator dependence. For accurate interpretation of regional wall motion abnormalities and recognition of ischemic changes, specific training and extensive experience are necessary. CONCLUSION: Although exercise echocardiography has only relatively recently become a widely used technique, it has proved to have considerable accuracy in the diagnosis of coronary artery disease (mean sensitivity, 84%; mean specificity, 87%). In high-volume laboratories, feasibility studies have shown success rates between 90 and 99%; thus far, reproducibility has been satisfactory. Other applications of exercise echocardiography being studied are follow-up monitoring after revascularization, determination of prognosis, and assessment of valvular heart disease.     

The effect of the suture-induced delay phenomenon on skin flap survival and lipid peroxidation in rats

To assess the prognostic significance of a normal dobutamine-atropine stress echocardiogram in relation to the pretest probability of coronary artery disease (CAD), 200 consecutive patients (86 men and 114 women, mean [SD] age 59 [13] years) with a stable chest pain syndrome and a normal dobutamine-atropine stress echocardiogram were followed-up for 21 +/- 16 months. Outcome events were cardiac death, non-fatal myocardial infarction, and coronary revascularization procedures. Low (<10%), intermediate (10% to 80%), and high (>80%) pretest probabilities of CAD were present in 27 (14%), 108 (54%), and 65 (33%) patients, respectively. During follow-up, 2 patients (annual event rate 0.6%) had cardiac death, none had nonfatal myocardial infarction, and 4 patients (annual event rate 1.1%) underwent a coronary revascularization procedure. All patients with cardiac events had high pretest probabilities of CAD. Patients with cardiac death (but unproven significant CAD) had maximal tests without angina or ischemic electrocardiographic changes. In contrast, all patients with subsequent coronary revascularization had dobutamine-induced angina or ischemic electrocardiographic changes, and all except one study were submaximal. We conclude that patients with a stable chest pain syndrome and normal findings on dobutamine-atropine stress echocardiograms have an excellent cardiac prognosis. However, patients with typical angina, high pre-test probabilities of CAD, and stress-induced angina or ischemic electrocardiographic changes, and in particular those with submaximal stress, still appear to be at risk for functionally important CAD despite a normal dobutamine-atropine stress echocardiogram.     

The effect of hyperoxia on embryonic and organ mass in the developing chick embryo

OBJECTIVES: We investigated the sensitivity and specificity of exercise-induced T wave normalization (TWN) in infarct-related electrocardiographic leads (IRLs) for detection of residual viability in the infarct area. BACKGROUND: The meaning of exercise-induced TWN on IRLs is not yet well understood. Recent reports suggest that TWN during dobutamine echocardiography could indicate the presence of viable myocardium. METHODS: We evaluated 40 consecutive patients with a recent acute myocardial infarction and negative T waves in at least two IRLs. All patients underwent exercise testing; positron emission tomography (PET) with nitrogen-13 ammonia and fluorine-18 fluorodeoxyglucose; and coronary angiography. RESULTS: Twenty-four patients showed exercise-induced TWN: 18 at a work load < or =50 W (group la) and 6 at a work load > or =75 W (group 1b); 16 patients did not show TWN (group 2). On the PET study, viability in the infarct area was present in 17 patients (94%) from group la, in only 1 (16%) from group 1b and in 4 (25%) from group 2 (p < 0.0001). The sensitivity, specificity and diagnostic accuracy of exercise-induced TWN, in comparison with residual viability, were, respectively, 82%, 67%, 75% for TWN at every work load and 77%, 94%, 85% for TWN at a work load < or =50 W. Moreover, the sensitivity and diagnostic accuracy of TWN at the low work load were higher for anterior infarctions (87% and 88%, respectively). CONCLUSIONS: Exercise-induced TWN on IRLs at low work loads is a sensitive and specific index for the presence of residual viability in the infarct area. Sensitivity and diagnostic accuracy of this sign are higher for anterior infarctions.     

Dobutamine stress echocardiography for assessing coronary artery disease after transplantation in children

OBJECTIVES: The purpose of this study was to determine the feasibility, safety and diagnostic accuracy of dobutamine stress echocardiography (DSE) for evaluating posttransplant coronary artery disease (TxCAD) in children, and to determine the frequency of selected cardiac events after normal or abnormal DSE. BACKGROUND: Posttransplant coronary artery disease is the most common cause of graft loss (late death or retransplantation) after cardiac transplantation (CTx) in children. Coronary angiography, routinely performed to screen for TxCAD, is an invasive procedure with limited sensitivity. The efficacy of DSE for detecting atherosclerotic coronary artery disease is established, but is unknown in children after CTx. METHODS: Of the 78 children (median age 5.7 years, range 3 to 18) entered into the study, 72 (92%) underwent diagnostic DSE by means of a standard protocol, 4.6 +/- 1.9 years after CTx. The results of coronary angiography performed in 70 patients were compared with DSE findings. After DSE, subjects were monitored for TxCAD-related cardiac events, including death, retransplantation and new angiographic diagnosis of TxCAD. RESULTS: No major complications occurred. Minor complications, most often hypertension, occurred in 11% of the 72 subjects. The sensitivity and specificity of DSE were 72% and 80%, respectively, when compared with coronary angiography. At follow-up (21 +/- 8 months), TxCAD-related cardiac events occurred in 2 of 50 children (4%) with negative DSE, versus 6 of 22 children (27%) with positive DSE (p < 0.01). CONCLUSIONS: DSE is a feasible, safe and accurate screening method for TxCAD in children. Positive DSE identifies patients at increased risk of TxCAD-related cardiac events. Negative DSE predicts short-term freedom from such events.     

Value of dobutamine echocardiography in the detection of coronary disease in heart transplant patient. Groupe de Recherche VACOMED]

The value of Dobutamine stress echocardiography in the detection of coronary artery disease in heart transplant patients was studied in 64 patients at control coronary angiography 39 +/- 14 months after transplantation. Dobutamine was infused at progressively increasing doses (5 to 40 micrograms/kg/min) at 5 minute intervals, in order to reach 85% of the theoretical maximal heart rate or an ischaemic event. Echocardiography was analysed in the 4 standard views which were digitised allowing calculation of a regional wall motion score under basal conditions and at peak dosage in 16 left ventricular segments. Coronary angiography identified three groups: group I: 29 patients with normal coronary arteries; group II: 17 patients with non-significant coronary disease (diffuse or localised stenosis < 50%); group III: 9 patients with significant (> 50%) coronary disease. Dobutamine stress echocardiography showed regional wall motion abnormalities in 2/29 patients in group I, 13/17 patients in group II and all patients in group III (global sensitivity: 85%; specificity: 97%). The contractility score was significantly higher under basal conditions in group III (1.45 +/- 0.54) than in group I (1) and group II (1.17 +/- 0.23). At peak dose, the contractility score was unchanged in group I and increased significantly (p < 0.01) in the other two groups. The authors conclude that Dobutamine echocardiography is a reliable, non-invasive method of detecting coronary disease in cardiac transplant patients, and is particularly valuable for demonstrating myocardial ischaemia related to coronary lesions judged to be not significant at coronary angiography.     

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.