Use Of Dobutamine Echocardiography Research Articles

121 - The Use of Dobutamine Echocardiography for Recovery Prediction in Cancer Patients with Newly Diagnosed Left Ventricular Dysfunction

Introduction: Myocardial viability is dependent on imaging evidence of myocardial functional reversibility. A variety of imaging modalities can analyze tissue viability and are used as a method to predict tissue recovery in patients with heart failure, but there is limited data and agreement on which modality is a better predictor of viability and recovery potential in cancer patients with newly diagnosed left ventricular systolic dysfunction (LVSD). Our previous analysis has demonstrated lower mortality outcomes in cancer patients with full recovery of LV systolic function. We predict that dobutamine stress echocardiography will be a measure viability and functional recovery potential in patients with new LVSD. Methods: We performed a prospective case assessment on cancer patients with new LVSD (LVEF < 50%). Based on inclusion and exclusion criteria, a total of 26 subjects were enrolled. The patients underwent dobutamine echocardiogram (intravenous doses 2.5 mcg, 5 mcg, 10 mcg) to evaluate dobutamine response. Complete recovery was defined as an increase in left ventricular ejection fraction (LVEF) of more than 10 absolute percent points and achieving an LVEF of more or equal to 50%. Partial recovery was defined as an increase in 10 absolute percent points but not achieving at least an LVEF of 50%. No recovery was defined as lack of increase in LVEF or an increase lower than 10 absolute percent points. Data was analyzed to assess the ability of dobutamine echocardiography in predicting recovery of LV systolic function. Results: Out of twenty-six patients, 19 patients (mean age 58 (19 - 85) years, 12 female) had echocardiographic evidence of augmentation with dobutamine (p-value 0.28). Twenty-six percent (n = 5) of these patient's showed full recovery. Twenty-six percent (n = 5) had a partial response and 48% (n = 9) showed no recovery. Seven patients (mean age 62 years, 7 female) had no echocardiographic evidence of augmentation with dobutamine. Of these 7 patients, none showed full recovery, 43% (n = 3) showed partial recovery and 57% (n = 4) showed no recover. Conclusions: The major finding from our small cohort of patients revealed that in cancer patients with new LVSD and lack of augmentation with dobutamine may suggest a dismal opportunity for complete LV systolic function recovery. Our sample size is a significant limitation to show the potential predictive capability that this technique may have. Larger studies are needed to examine the potential of dobutamine echocardiography in predicting functional recovery and outcomes in this population.

Stress imaging in patients with diabetes; routine practice?

Over the past years, echocardiography has been shown to play a crucial role in the accurate evaluation of left ventricular function particularly in patients suspected for ischemic heart disease [1–3]. The ability to rapidly perform bedside echocardiography with Echo-Doppler imaging places this modality in the heart of clinical research to understand cardiac function and to quantify various associated abnormalities [4–8]. Echocardiography has found a major niche in visualizing left ventricular function both at rest and during stress. Widespread use of dobutamine-echocardiography has contributed to more frequent recognition of wall motion disturbances due to coronary artery disease [9–11]. Its applicability in prognostic assessment of such patients has been repeatedly confirmed, particularly in diabetic subjects [12]. Coronary artery disease is the leading cause of morbidity and mortality in patients with diabetes mellitus. In fact, patients with diabetes have the same risk of myocardial infarction as do non-diabetic subjects with a history of infarction. Present data indicate a substantially elevated risk of cardiovascular disease even before a clinical diagnosis of type-2 diabetes has been made. Identifying patients with diabetes suspected for coronary artery disease who will benefit from medical and/or invasive intervention to prevent cardiovascular events is a challenge in both symptomatic and asymptomatic patients. The decision to evaluate patients with diabetes who are asymptomatic for coronary artery disease presents the greatest challenge; investigation will reveal 10–15% of these patients to have coronary artery disease. Current diagnostic tools include exercise tolerance testing [13–18], stress myocardial perfusion imaging [19–26], stress MRI [27–57], and stress echocardiography [12]. In the current issue of the International Journal of Cardiovascular Imaging, Innocenti et al. [58] studied 322 type-2 diabetic patients who underwent dobutamine-stress echocardiography for known or suspected coronary artery disease. Indications to dobutamine-stress echocardiography were evaluation of symptoms suggesting presence of coronary artery disease or assessment of known coronary artery disease. End-points of the study were all-cause mortality, cardiac death, and non-fatal myocardial infarction. During dobutamine-stress echocardiography, viability and inducible ischemia developed in 65 (20%) and 192 (60%) subjects, respectively. Severe ischemia (defined as an asynergic area including more than 40% of all segments combined with a rate pressure product <17000) appeared in 88 (27%) of patients. Presence of diabetic treatment or microvascular diabetic complications did not affect prognosis, while longer diabetes duration was associated with higher all-cause mortality at univariate analysis. At multivariate analysis, advanced age, decreased left ventricular ejection fraction, and peripheral vascular disease independently determined increased all-cause mortality. New hard cardiac events occurred more frequently in presence of peripheral vascular disease, viability and severe ischemia. The authors concluded that in diabetic patients with known or suspected coronary artery disease, presence of viability and severe ischemia during dobutamine-stress echocardiography are independently associated with a higher occurrence of hard cardiac events. The clinical variables showed a weak prognostic role, except for age and presence of peripheral vascular disease. These findings emphasize the role of stress echocardiography in patients with type-2 diabetes. It should, however, be realized, that the value of stress imaging in diabetic patients is dependent on the presence and nature of symptoms. In symptomatic patients, myocardial perfusion imaging provides similar diagnostic and prognostic accuracies as in patients without diabetes [59]. However, the utility of screening patients with type-2 diabetes for asymptomatic coronary artery disease remains controversial [60–62]. For instance, the Detection of Ischemia in Asymptomatic Diabetics (DIAD) study [62] assessed whether routine screening for coronary artery disease identified patients with type-2 diabetes as being at high cardiac risk and whether it affects their cardiac outcomes. A total of 1123 participants with type-2 diabetes and no symptoms of coronary artery disease were randomly assigned to be screened with adenosine-stress radionuclide myocardial perfusion imaging or no screening. It was found that in patients with diabetes, the cardiac event rates were low and were not significantly reduced by screening for myocardial ischemia over almost 5 years. Therefore, findings from the DIAD study indicate that routine screening of asymptomatic patients with diabetes is not justified. Notwithstanding, the current study [58] shows that dobutamine-stress echocardiography has a major role in the evaluation of diabetic patients. In symptomatic diabetic patients with known or suspected coronary artery disease, advanced age and reduced left ventricular function are independent predictors of total mortality. Presence of viability and severe ischemia during dobutamine-stress echocardiography are independently associated with higher occurrence of new major cardiac events. Therefore, dobutamine-stress echocardiography is an important prognostic imaging modality in assessing cardiovascular risk in symptomatic diabetic patients.

1071 Use of dobutamine echocardiography for cardiovascular event prediction in chronic kidney disease: clinical scoring algorithms can optimise patients selection for testing

1071 Use of dobutamine echocardiography for cardiovascular event prediction in chronic kidney disease: clinical scoring algorithms can optimise patients selection for testing

Ecocardiografía de ejercicio para diferenciar la miocardiopatía dilatada de la disfunción ventricular por cardiopatía isquémica

Previous studies have shown the usefulness of dobutamine echocardiography to differentiate dilated cardiomyopathy (DC) from ischemic left ventricular dysfunction (ILVD), but no studies have been made using exercise echocardiography (EE). We hypothesized that most patients with DC have some contractile reserve and experience an increase in left ventricular ejection fraction (LVEF) during exercise, as opposed to patients with ILVD. Differences in response to EE may be useful to clinically differentiate between these two entities. Between 1 March 1995 and 1 March 2001, we performed 4,133 EE studies on 3,830 patients. Of 289 patients (8%) with moderate or severe LV dysfunction (biplane LVEF < 41% and left ventricular end-diastolic diameter > 5.2 cm), 207 were excluded: 111 for a history of myocardial infarction; 28 for scarring on echocardiography (regional akinesia/dyskinesia with thinning and/or increased brightness); 13 for previous revascularization procedures; 9 for aortic valve disease; 11 for a known cause of cardiomyopathy; and 35 for not undergoing angiography. The study group was therefore composed of 82 patients who were encouraged to perform maximal treadmill EE. EE criteria for ILVD were either impaired regional wall motion (RWM) or a decrease/no change in LVEF from baseline to peak exercise, while criteria for DC were RWM improvement/no change and LVEF increase. The ILVD group was formed by 39 patients with stenosis >/= 70% diameter stenosis of a major epicardial coronary artery or major branch vessel. The remaining 43 patients constituted the DC group. The number of coronary risk factors (ILVD 2.0 1.1; DC 1.9 1.1), baseline LVEF (ILVD 30 7; DC 30 8), and exercise-induced angina (ILVD 23%; DC 14%) did not differ between groups (p = NS). ILVD patients achieved less Mets (6.6 3.1 vs 8.3 2.8; p < 0.05), had a lower heart rate x systolic blood pressure product (22 5 vs 27 7; p < 0.001), and developed regional and/or global LV dysfunction more frequently (79 vs 28%; p < 0.001). Sensitivity, specificity, positive and negative predictive values and global accuracy for ILVD detection were 79% (95% CI: 70-88), 72% (95% CI: 63-81), 72% (95% CI: 63-81), 79% (95% CI: 67-85), and 76% (95% CI: 69-83), respectively. Global and/or regional LV function impairment with exercise is accurate in identifying patients with ILVD. This method could reduce the need for invasive procedures.

Evaluation and Management of Patients With Aortic Stenosis

Case presentation: A 66-year-old man is referred to a cardiologist for the evaluation of a heart murmur. The patient claims to be entirely asymptomatic, although his wife notes that he has decreased his physical activity over the past two years because he is “getting old.” At physical examination, his blood pressure was 120/70 mm Hg; pulse, 80 bpm; respiration, 13 breaths per minute; and temperature, 99.0°F. Cardiovascular examination revealed normal central venous pressure. His carotid upstrokes were reduced in volume and delayed in upstroke. Cardiac examination revealed a forceful sustained apical impulse in its normal position. There was a 3/6 late-peaking systolic ejection murmur heard at the right upper sternal border radiating to the neck. The rest of the physical examination was unremarkable. Echo-Doppler evaluation revealed an ejection fraction of 0.60, a left ventricular free wall thickness of 1.3 cm, and a peak transaortic flow velocity of 4.5 m/s. How should this patient be managed? Should he undergo aortic valve replacement now? Should he undergo longitudinal follow-up to monitor progression of his aortic stenosis? Over the past 40 years, diagnostic techniques, substitute cardiac valves, and valve implantation surgery have undergone continued improvement, reducing the risk of the valve replacement and enhancing its benefits. Thus, the risk-benefit analysis of valve surgery has tilted in favor of increasingly early intervention for valve disease. The following is a summary incorporating this concept into the current strategy for managing patients with aortic stenosis such as the one described above. The patient with severe aortic stenosis who presents with symptoms represents the most straightforward management strategy for the disease. Survival is nearly normal until the classic symptoms of angina, syncope, or dyspnea develop.1 However, only 50% of patients who present with angina survive 5 years, whereas 50% survival is 3 years for patients who …

Pathophysiology of myocardial hibernation. Implications for the use of dobutamine echocardiography to identify myocardial viability

Since the pioneering works of Tennant and Wiggers,1 it has been known that total ischaemia leads to a prompt cessation of contraction and eventually results in the appearance of cell...

Use of dobutamine echocardiography for cardiac risk stratification of patients with chronic renal failure.

This study sought to define the value of dobutamine echocardiography (DbE) for cardiac risk stratification in patients with chronic renal failure (CRF). Outcome study correlating results of DbE with late cardiac events in patients with CRF. Academic medical centre. All patients with CRF (serum creatinine > 2.5 mg dL-1) undergoing DbE were studied; we analysed 193 consecutive patients (aged 63 +/- 13 years, 73 men). A standard dobutamine-atropine stress was administered until attainment of peak dose, or the development of severe ischaemia or side-effects. The electrocardiogram (ECG) and echocardiogram were obtained before, during and after stress. Ischaemia was identified by new or worsening wall-motion abnormalities with stress. Patients were followed up after 38 +/- 14 months for cardiac death, myocardial infarction or coronary disease progression requiring revascularization. DbE demonstrated ischaemia in 36 patients (19%), scar in 36 (19%) and a normal study in 121 patients. The heart-rate response to dobutamine was submaximal (< 85% age-predicted heart rate) in the absence of wall-motion abnormalities in 69 patients (36%), 54 of whom completed the protocol. Follow-up data were complete in 191 patients (99%); cardiac events occurred in 33 patients (17%), including 17 with cardiac death, 7 with infarction, and 9 requiring late revascularization. Spontaneous events occurred in 7 patients with ischaemia, 3 with scar (8%), 11 with a nondiagnostic study (16%) and 3 patients with a normal study (6%). Over the entire follow-up, the event-free survival in patients with ischaemia (66%) was markedly lower than those without ischaemia (84%, P = 0.006). However, the event rate in patients with nonischaemic responses increased from 8% to 16% between 24 and 40 months, and whilst ischaemia was an independent predictor of outcome at 24 months, it was not at 40 months. In patients with CRF, the identification of ischaemia at DbE is associated with a significant risk of adverse cardiac events. Patients with nonischaemic scans have a low frequency of events over short-term follow-up, but this increases at later follow-up. These later events may reflect progressive coronary disease, attributable to the atherogenic milieu of these patients, and imply that repeated testing may be required to maintain cardiac risk stratification in patients with CRF.

Assessment of myocardial viability: Dobutamine echocardiography and thallium-201 single-photon emission computed tomographic imaging predict the postoperative improvement of left ventricular function after bypass surgery

The aim of this study was to evaluate the usefulness of dobutamine echocardiography and quantitative thallium-201 single photon emission computed tomography myocardial scintigraphy with reinjection in the detection of viable myocardium in patients with coronary artery disease and reduced left ventricular function, which will improve after aortocoronary bypass surgery. Forty-eight patients (47 men, aged 61 ± 6 years) with angiographically documented reduced left ventricular function (ejection fraction 35 ± 14, 63% with chronic transmural myocardial infarction) were examined by dobutamine two-dimensional echocardiography (before and during low dosage), 201Tl , and gated radionuclide ventriculography before and 3 ± 2 months after aortocoronary bypass surgery. Four of 55 areas classified viable before operation were revascularized inadequately and discarded. Global left ventricular ejection fraction at rest rose from 35% ± 14% before operation to 40% ± 13% ( p < 0.05) after operation. Stress-induced perfusion defects involved 40% ± 19% of the left ventricle circumference after stress and showed a significant reduction of size to 23% ± 14% ( p < 0.01) at rest, 4 hours later, and after reinjection. This value fell to 16% ± 12% ( p < 0.05) 3 months after aortocoronary bypass surgery. We conclude that both dobutamine echocardiography (sensitivity 95%, specificity 80%, positive predictive value 87%, negative predictive value 88%) and 201Tl studies (sensitivity 87%, specificity 98%, positive predictive value 97%, negative predictive value 93%) are suitable and comparable accurate methods for predicting improvement in systolic function 3 months after revascularization in a selected population with a high prevalence of viable but hypokinetic or akinetic myocardium. (Am Heart J 1998;136:463-75.)

Usefulness of Dobutamine Echocardiography in the Hemodynamic Assessment of Mechanical Prostheses in the Aortic Valve Position

Dobutamine stress echocardiography is a simple, safe, and readily available method to evaluate prosthetic valve hemodynamics under various flow conditions. A normal response of aortic valve prostheses to dobutamine infusion is a 100% increment in transprosthetic pressure gradients with an unchanged valve area.

Combined use of dobutamine echocardiography and myocardial contrast echocardiography in predicting regional dysfunction recovery after coronary revascularization in patients with recent myocardial infarction

Myocardial contrast echocardiography and dobutamine echocardiography have recently emerged as potentially useful clinical tools to detect reversible myocardial dysfunction. However, the relative accuracy of these two techniques in predicting regional wall motion improvement after coronary interventions is still unclear. The aim of the present study was to compare their diagnostic value in predicting functional recovery after coronary revascularization in patients with recent acute myocardial infarction. Twenty-four patients with acute myocardial infarction underwent myocardial contrast echocardiography and dobutamine echocardiography within 2 weeks of hospital admission. Infarct zone contrast score and wall motion score indexes were derived in each patient. Infarct-related artery revascularization was performed before hospital discharge in all selected patients. Resting echocardiography was repeated 3 months after revascularization, and regional function recovery was analysed. The degree of wall motion score improvement at 3-month follow-up and the percentage of positive responses to dobutamine echo were greater (P < 0.001 and P < 0.002, respectively) in patients with a higher baseline contrast score (> or = 0.50). Conversely, no significant changes were observed either during dobutamine echo or after revascularization in the group of patients without residual perfusion within the infarct area. Diagnostic agreement between both techniques in predicting reversible dysfunction was high (81% of segments). The sensitivity and negative predictive value in predicting functional outcome were 100% (95% confidence interval [CI], 87% to 100%) and 100% (95% CI, 93% to 100%) by contrast echo, and 85% (95% CI, 66% to 96%) and 93% (95% CI, 84% to 98%) by dobutamine echo. The specificity and positive predictive value were 90% (95% CI, 80% to 96%) and 81% (95% CI, 64% to 93%) by contrast echo, and 88% (95% CI, 78% to 95%) and 76% (95% CI, 58% to 90%) by dobutamine echo. The combination of myocardial contrast and dobutamine echocardiography positive responses improved specificity and positive predictive value in detecting functional recovery after revascularization to 100% (95% CI, 94% to 100%) and 100% (95% CI, 85% to 100%), respectively. However, the sensitivity and negative predictive value slightly decreased with the use of both methods (85% [95% CI, 66% to 96%)] and (93%[95% CI, 85% to 98%)], respectively. In patients with recent myocardial infarction, reversible dysfunction after coronary revascularization and the response to dobutamine infusion are strictly dependent on microvascular integrity. However, microvascular perfusion does not always imply functional recovery after coronary revascularization. The integration with dobutamine echo results seems particularly helpful to further improve myocardial contrast echo specificity and positive predictive values.

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 dobutamine stress echocardiography as it has evolved at a single center and to define predictors of adverse events.Background. The indications and protocol 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 dobutamine stress studies were performed in 2,871 patients, using an incremental protocol from 5 to 40 μg/kg body weight per min in 3-min stages, followed by atropine or an additional stage with 50 μg/kg per min, if required. Clinical data were gathered prospectively, and hemodynamic and echocardiographic findings were recorded at each stage, including recovery. Dobutamine echocardiography was defined as positive for ischemia in the presence of new or worsening wall motion abnormalities; in the absence of ischemia, failure to attain 85% of age-predicted maximal heart rate was identified as a nondiagnostic result.Results. Studies were performed for risk assessment (70%) and symptom evaluation (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 with achievement of target heart rate (>85% maximal age-predicted heart rate); 455 patients (15%) failed to achieve >85% maximal predicted heart rate despite maximal doses of dobutamine and atropine. The protocol was stopped prematurely in 230 patients (7.6%) because of side effects, including ventricular (n = 27 [0.9%]) and supraventricular rhythm disorders (n = 22 [0.7%]), severe hypertension (n = 24 [0.8%]) and hypotension or left ventricular outflow tract obstruction (n = 112 [3.8%]). Noncardiac symptoms, such as headache, nausea or anxiety, caused early test termination in 45 patients (1.6%). The remaining tests were stopped because of severe chest pain (n = 106 [3.5%]) or severe ischemia by echocardiography (n = 26 [0.9%]). Serious complications occurred in nine patients, including sustained ventricular tachycardia in five, myocardial infarction in one and other conditions in three requiring hospital admission (sustained supraventricular tachycardia, hypotension, suspected myocardial infarction), but neither ventricular fibrillation nor death occurred. Independent predictors of serious complications could not be defined. Over 5 years, higher dose protocols and more frequent use of atropine have raised the number of diagnostic protocols from 59% to 80%, without increasing the incidence of major side effects.Conclusions. Despite the use of more aggressive protocols and alterations of the indications for testing to include sicker patients, major side effects are a rare complication of dobutamine echocardiography.(J Am Coll Cardiol 1997;29:1234–40)

Can dobutamine echocardiography distinguish necrotic from ischemic myocardium, early after myocardial infarction?

The aim of this study was to evaluate the usefulness of dobutamine echocardiography (DE) in distinguishing necrotic from ischemic myocardium in infarct zones. We performed DE in 39 patients, 3 to 5 days after admission for a first, acute myocardial infarction, treated with thrombolysis. DE was considered positive if wall motion in the infarct zone worsened progressively during increasing dose of dobutamine or if wall motion in the infarct zone initially improved at low dose of dobutamine and deteriorated at higher dose. The results of DE were correlated to the evolution of wall motion in the infarct zone after 3 months and to the need for supplementary balloon dilatation. In 15 of the 39 patients, there was evidence of residual ischemia in the infarct zone. Twenty of the 39 patients had a positive dobutamine echocardiogram. Eleven of these 20 patients had evidence of residual ischemia in the infarct zone. They showed generalized changes of wall motion in the total infarct territory during DE. The other 9 patients demonstrated only localized changes of wall motion in isolated segments of the infarct zone during DE. None of these patients had evidence of residual ischemia. DE seems worthwhile in the detection of residual ischemia in the region of infarction. To reduce the number of false positive DE early after myocardial infarction, only extensive changes of wall motion in the total infarct territory should be accepted as indicative of residual ischemia in the infarct zone.

Evaluation of the diagnostic use of dobutamine echocardiography and Tc99m sestamibi myocard perfusion scintigraphy for the detection of coronary artery disease

Evaluation of the diagnostic use of dobutamine echocardiography and Tc99m sestamibi myocard perfusion scintigraphy for the detection of coronary artery disease

Usefulness of dobutamine echocardiography in distinguishing severe from nonsevere valvular aortic stenosis in patients with depressed left ventricular function and low transvalvular gradients

The safety of dobutamine echocardiography in coronary artery disease is well established. 27 This study shows that dobutamine can be given safely to patients with AS during noninvasive hemodynamic monitoring. The small number of patients in this study preclude assessment of the effect of dobutamine echocardiography on outcome. A large prospective study is indicated. Although the continuity equation does not contain a flow-dependent constant, its limitations include underestimation of LV outflow diameter and failure to properly align the Doppler beam. 18 However, even if errors in velocity measurement occurred, directional changes should be valid since the transducer locations were identical at baseline and dobutamine infusion.

Usefulness of dobutamine echocardiography for detecting restenosis after percutaneous transluminal coronary angioplasty

To determine the usefulness of dobutamine stress echocardiography for detecting restenosis after percutaneous transluminal coronary angioplasty, the results of coronary arteriography and dobutamine stress echocardiography were compared in 103 patients 6 months after percutaneous transluminal coronary angiography. The dobutamine stress echocardiograms were obtained on the same day as the coronary arteriograms, which were analyzed by both quantitative and visual estimates of luminal narrowing. The angiographic restenosis rate was 44% by quantitative and 31% by visual estimates of stenosis. Dobutamine stress echocardiography was abnormal in 38% of previously dilated regions with restenosis and normal in 79% of previously dilated regions without restenosis by quantitative coronary angiography. Dobutamine stress echocardiography was concordant in 69% of 16 patients with multivessel disease compared with 40% of 41 patients with 1-vessel disease (p < 0.05). By quantitative coronary angiography, 64% of patients with significant disease in the left anterior descending artery were identified by dobutamine stress echocardiography compared to 12 and 24% of patients with disease in the left circumflex and right coronary arteries, respectively (p < 0.009). Concordance was seen in 79% of patients with baseline wall motion abnormalities compared with 54% of patients without baseline wall motion abnormalities. Dobutamine stress echocardiography has a low sensitivity but high specificity for detecting restenosis after coronary angioplasty, which may be explained in part by the high prevalence of 1-vessel disease in this patient population. The variables associated with significantly higher degrees of concordance were the presence of left anterior descending artery disease, multivessel disease, and baseline wall motion abnormalities.