Dobutamine stress echocardiography: correlation with coronary lesion severity as determined by quantitative angiography.

This study was performed 1) to determine the ability of dobutamine stress echocardiography to detect stenoses in individual coronary arteries by utilizing a new model of coronary artery distribution; 2) to evaluate its ability to detect coronary artery stenosis with a minimal lumen diameter less than 1 mm; and 3) to correlate the heart rate at which a positive test result occurs with the severity of coronary artery disease. Eighty-five patients were identified who underwent both dobutamine stress echocardiography and quantitative coronary angiography. During incremental infusion of dobutamine, two-dimensional echocardiograms were obtained at rest, during low and peak stress and after stress. Echocardiograms were interpreted with use of a modified 16-segment model with an anteroinferior overlap scheme. The overall sensitivity of the technique for the detection of significant coronary artery disease (diameter stenosis greater than or equal to 50%) was 95%; specificity was 82% and accuracy 92%. The sensitivity for detection of individual coronary artery lesions did not differ significantly (p greater than 0.05) in the three major coronary artery distributions (79% left anterior descending, 70% left circumflex, 77% right coronary artery). Among 35 stenoses with a minimal lumen diameter less than 1 mm, the test result was positive in 30 (86%). Test results were correctly positive for 88%, 82% and 86% of stenoses in the left anterior descending, left circumflex and right coronary artery distributions, respectively. Multivessel disease was present in 11 of 16 patients with normal wall motion at rest who developed a wall motion abnormality at a heart rate less than 125 beats/min. The incidence of multivessel disease was statistically higher in patients with positive findings on a dobutamine stress echocardiogram at a heart rate less than or equal to 125/min. In conclusion, dobutamine stress echocardiography has high sensitivity and specificity for the detection and localization of coronary artery disease. Detection of stenosis in individual coronary arteries is improved in those lesions with a minimal lumen diameter less than 1 mm. Patients with a positive test result at a heart rate less than or equal to 125 beats/min have a high likelihood of multivessel coronary artery disease.     

Dobutamine stress echocardiography before and after coronary angioplasty.

Myocardial function was assessed by stress echocardiography in 28 patients before and after successful elective coronary angioplasty. Dobutamine stress echocardiography was performed using up to 40 micrograms/kg/min, followed by the addition of atropine in 20 patients to achieve 85% of the predicted maximal exercise heart rate. The initial studies were performed 1 day before and the second ones within 3 days (mean 1.3) after angioplasty. Peak heart rates and systolic blood pressures were the same for the 2 studies. The frequency of dobutamine-induced new wall motion abnormalities decreased from 20 (71%) before to 4 (14%) after angioplasty (p less than 0.0001). Before angioplasty, wall motion score index (an indicator of left ventricular wall motion, an increase in which indicates impaired wall motion due to myocardial ischemia) increased from 1.06 at rest to 1.23 at peak stress (p less than 10(-6)), but there was no significant increase in this index in the study after angioplasty. Before angioplasty, 14 patients (50%) developed chest pain during the stress test compared with 6 (21%) after angioplasty (p = 0.05), and before angioplasty, the stress test was stopped before the target heart rate was achieved, because of symptoms, ST-segment change or severe new wall motion abnormality in 14 patients compared with 7 after angioplasty (p = 0.09). Thus, early after angioplasty there is a reduction in myocardial ischemia as assessed by dobutamine stress echocardiography.     

Dobutamine stress echocardiography

Two-dimensional echocardiography is a versatile, accurate, and readily available method for the assessment of cardiac anatomy and function, and extensive experience has been gained in the analysis of left ventricular wall motion. Using modern imaging techniques, regional as well as global wall motion analysis can be performed. Echocardiography can be used in conjunction with a protocol for either exercise or pharmacologic cardiovascular stress in order to identify the distribution and severity of coronary artery disease, with the induction of a regional wall motion abnormality being a sign of myocardial ischemia. The use of dobutamine infusion to accomplish stress echocardiography is a safe, accurate, and practical method for the diagnosis of coronary artery disease in patients unable to exercise. In addition to the evaluation of inducible ischemia, preliminary work is being performed with dobutamine stress echocardiography for the assessment of risk and patient prognosis following acute myocardial infarction and as an indication of tissue viability for myocardium that remains dysfunctional at rest following thrombolytic therapy.     

Dobutamine stress echocardiography for detection and assessment of coronary artery disease.

Stress echocardiography with dobutamine infusion for detection of coronary artery disease is a potential alternative to exercise stress testing with some theoretic advantages. Fifty patients who were not receiving cardioactive medication were prospectively studied with two-dimensional echocardiography and 12-lead electrocardiography (ECG) during incremental dobutamine infusion (5, 10, 15 and 20 micrograms/kg body weight per min, each dose for 8 min). Images were analyzed by using an 11-segment left ventricular model. All patients underwent correlative exercise ECG and coronary angiography, which revealed normal coronary arteries in 14 and significant disease (greater than or equal to 70% diameter stenosis) in 36. Peak rate-pressure product during dobutamine infusion was 18,845 +/- 4,156 versus 23,740 +/- 6,158 mm Hg/min on exercise (p less than 0.01). Interobserver concordance for wall motion analysis was good (kappa coefficient = 0.77). The use of baseline (n = 14) or reversible (n = 24) regional asynergy to define an abnormal dobutamine echocardiogram resulted in a sensitivity for detecting coronary artery disease of 78% and a specificity of 93%. Corresponding data for the dobutamine ECG were 47% and 71% and for the exercise ECG were 72% and 71%, respectively. The development of new mitral regurgitation on Doppler color flow imaging (n = 4) improved sensitivity to 81% without loss of specificity. Inducible asynergy or new mitral regurgitation was observed in 6 (50%) of 12 patients with single-, 6 (60%) of 10 with double- and 12 (86%) of 14 with triple-vessel disease. The site of transient asynergy provided additional localizing information. Exercise duration and time to diagnostic ST segment shift were shorter in patients with coronary artery disease with versus those without echocardiographic evidence of ischemia (both p less than 0.05). Side effects during dobutamine infusion were mild and short-lived. Dobutamine stress echocardiography is well tolerated, is useful for detection and assessment of coronary artery disease and is applicable to patients unable to exercise.     

Dobutamine stress echocardiography identifies anthracycline cardiotoxicity.

BACKGROUND: Anthracyclines are effective anti-cancer agents, but their therapeutic value is limited by their myocardial toxicity. We assessed the physiological responses of stress echocardiography at low doses of dobutamine (DSE) in patients treated with anthracycline. METHODS AND RESULTS: In a prospective study, 28 patients were studied before and 1 month after the end of chemotherapy. All patients had normal ejection fraction (EF) at rest before therapy and the mean dose of anthracycline was 212+/-15 mg/m(2). Echocardiographic Doppler studies were performed before and during dobutamine infusion (5 and 10 microg/kg per min). Rest echocardiography demonstrated a significant decrease of EF between the two examinations in ejection fraction (67+/-3% vs. 61+/-3%, P<0.001). The increase of the EF during dobutamine infusion was higher after chemotherapy compared to the initial examination (19+/-3% vs. 29+/-3%: P<.05). No difference in EF was observed at 10 microg/kg per min between before and after chemotherapy. In contrast, at rest no difference in diastolic parameters was observed between the two examinations. Moreover, a significant decrease of the peak E and the ratio E/A was observed during dobutamine infusion after chemotherapy (93+/-4 cm/s vs. 79+/-5 cm/s and 1.3+/-0.1 vs. 1.0+/-0.1, respectively;P<0.05). CONCLUSION: Stress echocardiography may prove to be a sensitive technique and useful non-invasive approach for evaluating subclinical anthracycline cardiotoxicity.     

Dobutamine stress echocardiography: its role in the diagnosis of coronary artery disease.

We have assessed the usefulness of dobutamine infusion for the diagnosis of coronary artery disease by using two-dimensional echocardiography and 12-lead electrocardiogram. Dobutamine was infused at incremental doses (up to a maximum of 40 micrograms kg-1 min-1) in 52 patients with chest pain; all the patients underwent coronary angiography; significant coronary artery disease was quantitatively defined as greater than or equal to 50% diameter stenosis. Thirty-six patients were on betablockers. The test was considered positive when new regional wall motion abnormalities appeared during dobutamine infusion. No significant side effects occurred in any patient during the test. Transient wall motion abnormalities were detected in 20 of 37 patients with coronary artery disease (sensitivity = 54%); ischaemic ST segment changes were present on ECG in nine patients (sensitivity = 24%). Dobutamine stress echocardiography was negative in 12 of 15 patients with coronary artery diameter stenosis less than 50% (specificity = 80%). Exercise electrocardiography (ECG) was performed in 35 of these 52 patients. Maximum heart rate and systolic blood pressure were significantly higher during exercise than during dobutamine stress test (127 +/- 23 vs 99 +/- 24 beats min-1, P less than 0.0001; 179 +/- 25 vs 152 +/- 30 mmHg, P less than 0.0001). The exercise ECG test was positive in 12 of the 26 patients with significant coronary artery disease (sensitivity = 46%), and dobutamine stress echocardiography in 16 (sensitivity = 62%). Dobutamine stress echocardiography test is a safe and feasible diagnostic test for the noninvasive diagnosis of coronary artery disease and can be performed in patients unable to exercise.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dobutamine stress echocardiography and troponin T as a marker of myocardial injury

Introduction and objectives. Troponin T (TnT) is a very specific marker of myocardial damage. Our objective was to describe TnT behavior after dobutamine stress echocardiography (EDOB) and evaluate its usefulness for improving the diagnostic power of EDOB.Methods. Blood levels of TnT were measured at baseline and 3, 6, 12, and 24 h after EDOB in 63 patients (mean age: 69 9; 38 males). Coronary angiography was performed on 36 patients.Results. EDOB was positive in 29 patients and there was an increase over baseline values in 15 of them (51%); EDOB was negative in 34 patients and there was only a rise in TnT in 7 (20%; p < 0.01). The TnT increment was higher in patients with a positive response to EDOB (0.033 0.02 vs. 0.026 0.01; p < 0.01). The ischemia score index was higher in patients in which a significant increase in TnT values was later detected (0.41 0.31 vs. 0.38 0.20; p < 0.01). Coronariography was performed in 36 patients. EDOB was positive in 22 of the 29 patients with coronary artery disease (76%) and TnT was raised in 14 of them (48%; p < 0.05).Conclusion. The rise in TnT levels during EDOB suggests that this test may produce myocardial damage associated with the appearance of contractility disorders during dobutamine infusion.     

Dobutamine stress echocardiography: initial experience of a Canadian centre.

OBJECTIVE: To investigate the diagnostic accuracy, electrocardiogram and hemodynamic effects and safety of dobutamine stress echocardiography. SUBJECTS: Sixty-one patients with suspected coronary artery disease. All patients underwent coronary arteriography. MAIN RESULTS: The sensitivity of dobutamine stress echocardiography in diagnosis of coronary artery disease in the whole group was 91%. In patients with left anterior descending it was 97%; right 85%; circumflex 76%; three vessel 100%; two vessel 95%; single vessel 77%. Specificity, positive predictive value and accuracy of dobutamine stress echocardiography in diagnosis of coronary disease (whole group) was 57, 94 and 87%, respectively. ST depression of more than 1 mm occurred in 11 patients, ST elevation of more than 1 mm in three patients, T wave inversion in one and T normalization in nine. Significant differences of the effects of beta-blockers were noted on the peak effects of dobutamine as follows: heart rate increase of 46 +/- 22 versus 20 +/- 13 beats/min (P less than 0.0001); systolic pressure increase of 4 +/- 26 versus 22 +/- 19 mmHg (P less than 0.01); diastolic pressure decrease of 18 +/- 16 versus 10 +/- 12 mmHg (P less than 0.03) for patients without or with beta-blockers, respectively. Unifocal ventricular premature beats were noted in 10 patients, atrial premature beats in five and ventricular couplets in one. Angina occurred in 11 patients. Atypical chest pain occurred in seven patients, tingling in 11 and nausea in four. Thirty-six patients were totally asymptomatic. CONCLUSIONS: In this population with high prevalence (85%) of coronary artery disease, dobutamine stress echocardiography had high sensitivity and positive predictive value for coronary disease detection particularly in patients with left anterior descending or three vessel disease. The specificity and accuracy were not as good, but this may reflect the small number of normal patients. Dobutamine was well tolerated and conveniently administered.     

Dobutamine stress echocardiography for the detection of coronary artery disease in women

Dobutamine stress echocardiography (DSE) has good diagnostic accuracy for the diagnosis of coronary artery disease (CAD). However, in most published diagnostic studies, patients are predominantly men. In women, diagnostic accuracy may be lower because of a lower prevalence and extent of CAD, a higher incidence of dobutamine stress-induced hypotension (resulting in less stress or even nondiagnostic test results), smaller left ventricular chamber size, and the beneficial effects of estrogens on the induction of myocardial ischemia. To determine the diagnostic accuracy of DSE in women, 14 diagnostic studies published through 2006 were identified through a Medline search. For a total of 901 patients, the weighted mean sensitivity and specificity were 72% and 88%, respectively. In 7 studies directly comparing results in women and men, conflicting results were reported. However, pooled data showed nearly identical values for sensitivity and specificity in women and men. Additionally, in 6 studies directly comparing DSE results in women with those of stress nuclear scintigraphy, DSE was as sensitive and more specific to detect CAD (90% vs 70%, p <0.0001). The excellent specificity of DSE in women was also confirmed by excellent normalcy rates, ranging from 92% to 100% in women, with a <5% pretest probability of CAD. In conclusion, despite some theoretical limitations, DSE has reasonable sensitivity and excellent specificity for the detection of CAD in women. Considering the diagnostic problems of exercise electrocardiography and nuclear scintigraphy in women, stress echocardiography may be the stress modality of choice in women because of its superior diagnostic specificity.     

Dobutamine stress echocardiography for the diagnosis and management of coronary artery disease

Infusion of dobutamine in low and high doses in combination with echocardiography can be used for the assessment of myocardial viability and functional significance of coronary artery disease. Improvement of contractile function of hypokinetic or akinetic ventricular wall segment with low-dose dobutamine has a high predictive value for the detection of hibernating and stunned myocardium. High-dose dobutamine stress is of value for noninvasive diagnosis of coronary disease, assessment of its clinical significance, risk stratification of patients after myocardial infarction, preoperative evaluation of patients undergoing major noncardiac surgery, and assessment of the efficacy of coronary revascularization. It has an excellent safety record even in the immediate postmyocardial infarction period.     

Correlation between echocardiographic calcium score and coronary artery lesion severity on invasive coronary angiography

ObjectivesThe direct correlation between Echocardiographic non-coronary calcium score (ECS) and lesion severity on invasive coronary angiography (ICA) is not reported. The aim of the present study was to find the correlation between ECS and Gensini score.MethodsOne hundred seventy patients aged ≥18 years posted for clinically indicated ICA were included. All the patients underwent standard transthoracic echocardiography. ECS and Gensisni scores were calculated. The primary outcome measure was to find a correlation of ECS with Gensini score, whereas the secondary outcome measure was to correlate ECS with traditional risk factors for coronary artery disease. The Chi-square/Fisher exact test was used to compare qualitative variables. Spearman’s correlation analysis was used for assessing the correlation between ECS score and the Gensini score. Receiver-operating characteristic curve analysis was performed to detect the cut-off value of the ECS score.ResultsThe correlation of total ECS with Gensini score was positive and statistically significant (r = 0.550, p-value < 0.0001). As ECS increased, the Gensini score increased. ECS value of >1 detected CAD with 56.5% sensitivity, 79.5% specificity. Eight-nine percent of patients who had ECS >1, had Gensini score ≥18, whereas 44.3% of patients who had ECS ≤1, had Gensini score ≥18. The patients with ECS >1 had significantly higher Gensini scores than the patients with ECS ≤1.ConclusionsThe correlation of total ECS with Gensini score was positive and statistically significant.     

Dobutamine stress echocardiography in hypertrophic cardiomyopathy

AIMS: Myocardial ischemia in the absence of coronary artery disease is common in patients with hypertrophic cardiomyopathy (HCM). Dobutamine stress echocardiography (DSE) induces left ventricular (LV) new wall motion abnormalities (NWMA) in some patients with HCM. We evaluated the effects of dobutamine on LV performance and hemodynamics in HCM. METHODS AND RESULTS: Eighteen patients with non-obstructive HCM underwent DSE. Dobutamine was administered at dosages of 5, 10, 20, 30 and 40 microg/kg/min with increments at intervals of 3 min. Seven patients developed NWMA, whereas the other 11 did not. During DSE, heart rate increased significantly more in NWMA patients,whereas LV outflow tract gradient (OTG) increased significantly and similarly in both groups. At peak dobutamine dose, NWMA patients had a significant increase in LV end-systolic diameter and volume and a significant decrease in LV fractional shortening and ejection fraction. Posterior wall thickening increased significantly, whereas septal thickening did not increase throughout DSE in both groups. CONCLUSIONS: In a subgroup of patients with HCM, DSE induces NWMA, associated with a greater increase in heart rate, irrespective of LVOTG. NWMA induce a depression of global LV systolic performance. The septum shows no contractile reserve, regardless of NWMA. These phenomena may be the result of induction of ischemia and/or impaired LV systolic function due to fast heart rate.     

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.     

Dobutamine stress test to diagnose the presence and severity of coronary artery lesions in angina.

To calculate the accuracy of dobutamine infusion as a stress test to detect coronary lesions, 90 patients with angina and nine asymptomatic subjects with nonsignificant coronary lesions were submitted to a dobutamine test and coronary arteriography. Dobutamine was given in doses of 5, 10, 15 and 20 micrograms kg-1 min-1 every 5 min; a 12 lead ECG and blood pressure was monitored. Pressure x rate product increased from 8240 +/- 1667 to 14,898 +/- 3042. The test was negative (neither angina pain, nor ST segment shift) in 31 patients, and positive in 68. The ST segment was depressed in 33 cases and elevated in 20. Significant (greater than or equal to 50%) coronary lesions were seen in 63 patients and functional (coronary spasm or vasoconstriction) abnormalities in six. The sensitivity of the dobutamine test for the detection of coronary lesions was 95%, specificity 78%, predictive value of a positive test 88%, of a negative test 90% and diagnostic efficiency 89%. Strongly positive tests predicted severe lesions in 91% of the cases, and slightly positive tests ruled out severe lesions in 84%. ST segment elevation was induced in 20 cases and corresponded to a severe coronary lesion. In conclusion, the dobutamine stress test is a simple and accurate method of predicting coronary artery disease in patients with angina, distinguishing between severe and mild lesions. It can be a good alternative to an exercise test.     

Lipoprotein (a) as a predictor of severity of coronary artery stenosis documented by angiography in male coronary patients under 50 years old

OBJECTIVE: To determine the relationship between lipoprotein (a) seric levels with the age of coronary artery disease debut and the severity of coronary lesions in a group of male patients less than 50 years old. PATIENTS AND METHODS: We studied a group of 230 male patients, younger than 50 who were consecutively admitted to the hospital because of an ischemic coronary event. During hospitalization, the lipoprotein (a) in plasma was measured in all patients. They were distributed in two groups according to age at time of coronary disease clinical presentation with a cut off age of 40. A group of 142 patients underwent a cardiac catheterism and coronariography due to clinical or electrical unstability. RESULTS: The lipoprotein (a) levels were related with the number of diseased vessels. In this way lipoprotein (a) levels were 12 mg/dl (1.5-75) in those patients showing a normal coronariography; 27 mg/dl (2. 5-96) in those with one vessel disease; 34 mg/dl (7-90) in those with two vessels affected and 63 mg/dl (2-116) in the case of three-vessel disease, with statistical significance of p = 0.003. No significant differences in lipoprotein (a) levels were found when the age of coronary artery disease presentation was taken into account. In this way lipoprotein (a) levels were 31 mg/dl (2-97) in patients younger than 40 years of age, in comparison to 33 mg/dl (2-94) in those older than 40. CONCLUSIONS: In our community male patients with a diagnosis of coronary artery disease and less than 50 years old showed a relationship between lipoprotein (a) levels and the severity and number of coronary vessel diseases. However, an association between lipoprotein (a) levels with the age of coronary disease presentation was not evident.