Safety and feasibility of dobutamine and dipyridamole stress echocardiography in hypertensive patients

OBJECTIVES : To establish whether safety and feasibility of dobutamine and dipyridamole stress echocardiography are affected by history of hypertension. METHODS : Data on 2200 consecutive pharmacologic stress echocardiography (959 dobutamine and 1241 dipyridamole) performed between October 1990 and February 2001 at a single cardiology centre, were analysed. RESULTS : There were two complications (1/480 tests) during dobutamine (one sustained ventricular tachycardia and one severe asthmatic attack following antidote administration) and two (1/620 tests) during dipyridamole (one non-Q wave myocardial infarction and one sustained ventricular tachycardia) stress. Complications or limiting side effects were observed in 83/959 patients (48/430 hypertensives and 35/529 normotensives) with dobutamine and in 34/1241 patients (17/571 hypertensives and 17/670 normotensives) with dipyridamole stress. Therefore, the overall feasibility was 88.8% in hypertensives and 93.4% in normotensives (P = 0.013) for dobutamine, and 97% in hypertensives and 97.5% in normotensives (P = 0.64) for dipyridamole. Dipyridamole was significantly more feasible than dobutamine in both hypertensive (P < 0.0001) and normotensive (P = 0.0006) subjects. Logistic regression analysis failed to identify clinical or echocardiographic predictors of adverse reactions with dipyridamole, while history of hypertension [odds ratio (OR) = 1.8, 95% confidence interval (CI) 1.1-2.8, P = 0.0138] was the only independent predictor of cumulative adverse reactions with dobutamine stress. In addition, history of hypertension (OR = 3.2, 95% CI, 1.2-8.5, P = 0.0166), resting wall motion abnormalities (OR = 1.8, 95% CI, 1.1-3.1, P = 0.0282), and age over 70 years (OR = 4.8, 95% CI, 1.5-15.3, P = 0.0087) predicted hypertensive response, ventricular tachycardia, and atrial fibrillation, respectively. No covariate was associated with hypotensive response during dobutamine test. CONCLUSIONS : Dipyridamole has a slightly better safety profile and significantly higher feasibility than dobutamine stress both in hypertensives and in normotensives. In addition, the history of systemic hypertension is an independent predictor of cumulative adverse effects during dobutamine but not during dipyridamole stress.     

Safety and feasibility of dobutamine stress echocardiography in patients with implantable cardioverter defibrillators

Coronary artery disease is the underlying etiology of left ventricular dysfunction and arrhythmias in most patients who receive implantable cardioverter defibrillators (ICDs). The aim of this study was to assess the safety and feasibility of dobutamine stress echocardiography (DSE) in patients with an ICD. DSE (dobutamine up to 50 microg/kg/min, atropine up to 2 mg) was performed in 87 patients with an ICD and known or suspected coronary artery disease. The ICD was inactivated before the stress test and reactivated after the study; no serious complications occurred. DSE is a safe and feasible method for evaluating myocardial ischemia in patients with an ICD.     

Safety, feasibility, and diagnostic accuracy of accelerated high-dose dipyridamole stress echocardiography

Protocols for dipyridamole stress testing have evolved in the last 16 years in the neverending quest of optimal diagnostic accuracy and user friendliness. Higher dipyridamole dose in a shorter infusion time provides higher sensitivity, but concern over safety is still controversial. An accelerated high-dose (0.84 mg/kg in 6 minutes without atropine) dipyridamole stress test was performed on 1,295 patients in 2 echocardiographic laborotories: Institute of Clinical Physiology of Pisa and Niguarda Hospital of Milan. During testing, there were no deaths and no patients had ventricular fibrillation. Major adverse reactions occurred in 3 cases (1 every 431 studies): 1 myocardial infarction, 1 brief cardiac asystole, and 1 transient ischemic attack. Overall feasibility was 97%. In 66 patients with normal function at rest who were evaluated off therapy, with coronary angiography performed independently of test results, the accelerated high-dose protocol showed a sensitivity of 85% (confidence interval [CI] 73% to 92%) and a specificity of 93% (CI 83% to 97%) for angiographically assessed coronary artery disease (quantitatively assessed diameter reduction > or = 50%). Diagnostic accuracy of the accelerated high dose was 89% (CI 79% to 95%). Thus, accelerated high-dose dipyridamole stress echocardiography was reasonably safe and well tolerated. This protocol is especially appealing for its excellent diagnostic accuracy coupled with the short imaging time and no need for drug cocktails.     

Diagnostic and prognostic use of stress echocardiography in stable patients

Stress echocardiography is an effective diagnostic and prognostic technique in stable patients with known or suspected coronary artery disease (CAD), myocardial infarction, or chronic left ventricular dysfunction and those undergoing noncardiac surgery. Stress echocardiography is sensitive and specific for the detection and extent of CAD. Negative tests confer a high negative predictive value for cardiac events regardless of the clinical risk. Positive studies confer a high positive predictive value for ischemic events in patients with intermediate to high clinical risk. Stress echocardiography provides incremental prognostic information relative to clinical, resting echocardiographic, and angiographic data. Meta-analysis studies have shown that the diagnostic and prognostic information provided by stress echocardiography is comparable to that from radionuclide scintigraphic stress tests. Stress echocardiography may be more specific for the detection and extent of CAD, whereas radionuclide scintigraphy may be more sensitive for one-vessel disease. Sensitivities are similar for the detection and extent of disease in patients with multivessel CAD.     

Comparison of prognostic value of pharmacologic stress echocardiography in chest pain patients with versus without diabetes mellitus and positive exercise electrocardiography

The aim of this study was to compare the prognostic value of pharmacologic stress echocardiography in diabetic and nondiabetic patients with chest pain and intermediate- to high-threshold positive exercise electrocardiographic results. A total of 935 patients with chest pain (131 diabetic patients) with ST-segment depression > or =1 mm on exercise electrocardiography at > or =75-W workload underwent dipyridamole (n = 786) or dobutamine (n = 149) stress echocardiography and were followed up for the occurence of hard (death and infarction) and major events (death, infarction, and late revascularization). During a median follow-up of 26 months, 158 events (51 deaths, 28 myocardial infarctions, and 79 late revascularizations) occurred: 34 in diabetic and 124 in nondiabetic patients (26% vs 15%, p = 0.003). Independent predictors of hard events were age, diabetes, and ischemia at stress echocardiography. Five-year hard event rates were 24% in patients with and 4% in those without ischemia (p <0.0001). Independent predictors of major events were age, diabetes, hypercholesterolemia, smoking habit, antianginal therapy at the time of testing, and ischemia at stress echocardiography. Five-year major event rates were 46% in patients with and 7% in those without ischemia (p <0.0001). Stress echocardiography results yielded effective prognostic information in diabetic and nondiabetic patients. However, the latter had worse outcomes in both the presence and absence of ischemia. Nevertheless, a nonischemic test result predicted an uneventful 6-month period and 2% major event rate at 1-year follow-up in both populations. In conclusion, stress echocardiography was effective in risk stratifying diabetic and nondiabetic patients with intermediate- to high-threshold ischemic exercise electrocardiographic results. However, major event rates associated with a nonischemic test result were similar in diabetic and nondiabetic patients during the first year of follow-up and markedly increased in the former thereafter.     

Stress-Doppler echocardiography in the diagnosis of ischemic heart disease in an ambulatory setting]

Coronary arteriography, bicycle ergometry and transesophageal atrial pacing (TAP) in combination with Doppler echocardiography (stress-Doppler echocardiography) were used to evaluate cardialgias in 30 outpatients. Stress-Doppler echocardiography showed a high (94%) sensitivity and a high (86%) specificity to detect coronary heart disease (CHD). There was a high correlation (r = 0.79, p less than 0.001) between the wall motion values obtained by echocardiography during TAP and coronary rating. The left ventricular (LV) diastolic filling (DF) was studied by pulsed wave Doppler echocardiography in the postpacing period. The Doppler-derived parameters of LV DF obtained in that period appeared to be moderately sensitive (75%) and specific (64%) in detecting CHD. In post-pacing ischemia, the "pseudonormalized" LV filling pattern was observed in 5 of 6 patients (sensitivity 80%) having three-vessel disease and major left (or equivalent) coronary stenosis.     

Prognostic value of pharmacologic stress echocardiography in patients with left bundle branch block

PURPOSE: Although coronary artery disease is a frequent cause of left bundle branch block, the prognostic value of myocardial ischemia in patients with this conduction abnormality has not been defined. We investigated the value of pharmacologic stress echocardiography in risk stratification of patients with left bundle branch block. PATIENTS AND METHODS: Three hundred eighty-seven patients [230 men and 157 women, mean (+/- SD) age, 64 +/- 9 years] with complete left bundle branch block on the resting electrocardiogram underwent dobutamine (n = 217) or dipyridamole (n = 170) stress echocardiography to evaluate suspected or known coronary artery disease. A summary wall motion score (on a one to four scale) was calculated. The primary end points were cardiac death and nonfatal myocardial infarction. RESULTS: A positive echocardiographic result (evidence of ischemia) was detected in 109 (28%) patients. During a mean follow-up of 29 +/- 26 months, there were 21 cardiac deaths and 20 myocardial infarctions, 63 patients underwent coronary revascularization, and 1 patient received a heart transplant. In a multivariate analysis, four clinical and echocardiographic variables were associated with increased risk of cardiac death: resting wall motion score index [hazard ratio (HR) = 7.5 per unit; 95% confidence interval (CI), 2.8 to 20; P = 0.001], previous myocardial infarction (HR = 2.9; 95% CI, 1.1 to 7.3; P = 0.02), diabetes (HR = 2.7; 95% CI, 1.1 to 6.6; P = 0.03), and the change in wall motion score index from rest to peak stress (HR = 3.0 per unit; 95% CI, 1.0 to 8.6; P = 0.04). The 5-year survival was 77% in the ischemic group and 92% in the nonischemic group (P = 0.02). Four variables were associated with increased risk of cardiac death or infarction: previous myocardial infarction (HR = 3.4; 95% CI, 1.7 to 6.8; P = 0.0005), diabetes (HR = 2.4; 95% CI, 1.2 to 4.6; P = 0.01), resting wall motion score index (HR = 2.2 per unit; 95% CI, 1.1 to 4.1; P = 0.02), and positive echocardiographic result (HR = 2.2; 95% CI, 1.1 to 4.5; P = 0.03). The 5-year infarction-free survival was 60% in the ischemic group and 87% in the nonischemic group (P < 0.0001). Stress echocardiography significantly improved risk stratification in patients without previous myocardial infarction (P = 0.0001), but not in those with previous myocardial infarction (P = 0.08). In particular, it provided additional value over clinical and resting echocardiographic findings in predicting cardiac events among patients without previous infarction. CONCLUSIONS: Myocardial ischemia during pharmacologic stress echocardiography is a strong prognostic predictor in patients with left bundle branch block, particularly in those without previous myocardial infarction.     

Complications of pharmacologic stress echocardiography in coronary artery disease

In the last few years, pharmacologic stress echocardiography is emerging as a promising diagnostic tool with a favorable cost/benefit ratio. Its main clinical applications include the assessment of coronary artery disease, the identification of viable myocardium, and risk stratification before major vascular surgery. However, cardiac (arrhythmic, ischemic, or hemodynamic) as well as noncardiac complications have been reported, so that a risk/benefit analysis is advisable in view of the extensive introduction of this technique in the clinical arena. The most popular pharmacologic agents employed for stress echocardiography are dipyridamole, do-butamine, and adenosine. A comparative analysis with exercise stress testing, the classical standard of reference of all ischemia-provoking tests, confirms that in terms of safety and tolerability pharmacologic stress echocardiography may be considered a good alternative in patients unable to exercise maximally. No appreciable difference among the safety profiles of the most common pharmacologic agents has been found, but a careful evaluation of the risk/benefit ratio is advisable for any stressor in the individual patient by considering the relative importance of the expected diagnostic contribution and the pharmacodynamic impact of the test. Finally, adequate training of the operator and monitoring of the patient during stress and recovery are essential for getting optimal safety conditions.     

Safety of dobutamine stress echocardiography in patients with aortic stenosis

BACKGROUND AND AIM OF THE STUDY: Aortic valve disease is becoming one of the most important cardiac diseases in western society. Low-dose dobutamine stress echocardiography (DSE) is recommended in patients with low-gradient aortic stenosis (AS) and severe left ventricular (LV) dysfunction. DSE is also used in patients with AS and moderately reduced or normal LV function for diagnostic purposes. The study aim was to assess the safety of DSE in the setting of AS and various degrees of LV dysfunction. METHODS: A total of 75 patients with AS who underwent DSE at the authors' center between 1997 and 2001 was reviewed. Group A patients (n = 20) had severely reduced mean LV ejection fraction (LVEF) of 25 +/- 6% and underwent low-dose DSE; group B patients (n = 55) had moderate to normal LV function (LVEF 51 +/- 8%) and underwent high-dose DSE. The mean pressure gradient, valve area and side effects after DSE were evaluated. RESULTS: Serious cardiac arrhythmias occurred in 10 patients. In group A, four patients (20%) developed non-sustained ventricular tachycardia. In group B, two patients (4%) had non-sustained ventricular tachycardia (VT), four (7%) had paroxysmal supraventricular tachycardias, and two (4%) severe symptomatic hypotension. Among the 20 patients with evidence of ischemia on DSE, three developed adverse side effects (no difference compared with patients without ischemia; p = 0.922). Fourteen patients received atropine during DSE, and 1 of these developed non-sustained VT after atropine administration. CONCLUSION: Serious cardiac arrhythmias occur frequently during both low-dose and high-dose DSE in patients with AS. Adverse side effects do not relate to stress-induced ischemia or atropine addition.     

Safety and prognostic value of early dobutamine-atropine stress echocardiography in patients with spontaneous chest pain and a non-diagnostic electrocardiogram.

AIMS: To risk stratify and shorten hospital stay in patients with spontaneous (resting) chest pain and a non-diagnostic electrocardiogram (ECG). METHODS AND RESULTS: The study comprised 102 patients (mean age 58+/-12 years, 67 men) with spontaneous chest pain and a non-diagnostic ECG. Forty-three patients had suspected coronary artery disease and 59 had known (but of unknown actual significance) coronary artery disease. All patients underwent serial creatine kinase enzyme measurements, continuous ECG monitoring for at least 12 h and early dobutamine-atropine stress echocardiography in patients with negative creatine kinase enzymes and normal findings at ECG monitoring. Dobutamine-atropine stress echocardiography was considered positive in patients with new or worsening wall thickening abnormalities. Patients with negative dobutamine-atropine stress echocardiography were discharged after the test. In-hospital and 6 month follow-up events noted were cardiac death, non-fatal myocardial infarction, unstable angina, and coronary artery bypass surgery or angioplasty. Thirteen patients had evidence of evolving myocardial infarction by elevated creatine kinase enzymes, or unstable angina by ECG monitoring. In the remaining 89 patients, dobutamine-atropine stress echocardiography was performed after a median observation period of 31 h (range 12-68 h). During dobutamine-atropine stress echocardiography no serious complications (death, non-fatal myocardial infarction, sustained ventricular tachycardia or ventricular fibrillation) occurred. Dobutamine-atropine stress echocardiography results were of poor quality in three, non-diagnostic in six, negative in 44 and positive in 36 patients. In the 80 patients with diagnostic dobutamine-atropine stress echocardiography, variables associated with in-hospital events (n=7) were history of exertional angina (P<0. 005), chest pain score (P<0.005), stress-induced angina (P<0.001) and positive dobutamine-atropine stress echocardiography (P<0.005). Variables associated with follow-up events (n=11) were history of exertional angina (P<0.05), chest pain score (P<0.001), stress-induced angina (P<0.01) and positive dobutamine-atropine stress echocardiography (P<0.01). At multivariate analysis the only significant predictor of events was positive dobutamine-atropine stress echocardiography (P<0.01). CONCLUSION: Early dobutamine-atropine stress echocardiography may safely distinguish between low- and high-risk subsets for subsequent cardiac events in patients with spontaneous chest pain and a non-diagnostic ECG.     

Usefulness of pharmacologic stress echocardiography in a chest pain center

We tested the value of a stress echocardiography-based algorithm used in a chest pain center. The algorithm had superlative negative predictive value for cardiac events, allowing an early discharge.     

Safety and feasibility of two-dimensional echocardiography and myocardial perfusion imaging in patients with chest pain

The accurate identification of patients at high risk for acute coronary syndromes among those seen in the emergency department with possible myocardial ischemia and nonischernic electrocardiograms is a problem. Two-dimensional echocardiography and myocardial perfusion imaging with 99m-technetium sestamibi can identify patients at low and high risk; however, comparative studies are lacking. The authors studied 555 patients considered at low or moderate risk for myocardial ischemia in our emergency department on the basis of the presenting history, and results of physical examination and electrocardiography. These patients underwent echocardiography and myocardial perfusion imaging within 4 hours of presentation. Endpoints included myocardial infarction, percutaneous transluminal coronary angioplasty, and positive results on stress perfusion imaging. Both imaging procedures were performed in the emergency department on 370 patients. Overall agreement between the two techniques was high (concordance, 89%) in the patients who had myocardial infarction or underwent coronary angiography. Agreement between the two techniques is high when used in patients with possible myocardial ischemia. Both techniques helped identify patients at high risk who required admission and those who could be safely discharged.     

Long-term prognostic value of dobutamine stress echocardiography in patients with atrial fibrillation

STUDY OBJECTIVE: To assess the long-term prognostic value of dobutamine stress echocardiography (DSE) for cardiac events (cardiac death, myocardial infarction, and late revascularization) in patients with atrial fibrillation (AF). METHODS: Baseline ECGs were studied in patients undergoing DSE between 1989 and 1998. Sixty-nine patients had AF before DSE. Prognostic value of DSE in these patients was compared with a control group who had sinus rhythm (n = 1,664). The presence of stress-induced ischemia was noted for every patient. The mean follow-up period was 35 months (range, 6 to 84 months). Data are presented as hazards ratio (HR) with 95% confidence interval (CI). RESULTS: Heart rate at rest was higher in patients with AF (77 +/- 15 beats/min vs 73 +/- 14 beats/min; p = 0.04); however, double product at peak stress was not different between patients with AF and sinus rhythm (17,602 vs 17,169, respectively; p = 0.46). In patients with AF, target heart rate was achieved at a lower dobutamine dose (33 +/- 8 microg/kg/min vs 35 +/- 9 microg/kg/min; p = 0.01). Cardiac arrhythmias occurred more frequently (12% vs 5%; p = 0.001) in patients with AF during DSE. During a follow-up period of 7 years, cardiac death occurred in 5 patients, myocardial infarction in 2 patients, and late revascularization in 10 patients. Prognostic value of DSE for all late cardiac events was similar in patients with AF (HR, 3.0; 95% CI, 0.9 to 9.5) and sinus rhythm (HR, 3.4; 95% CI, 2.7 to 4.3; p = 0.85). CONCLUSION: The prognostic value of DSE for late cardiac events is maintained in patients with AF.     

Prediction of mortality in patients with right bundle branch block referred for pharmacologic stress echocardiography

Right bundle branch block (RBBB) is independently associated with all-cause mortality in patients referred for noninvasive evaluation of coronary artery disease. However, further stratification of risk in these patients has not been specifically addressed. The aim of this study was to risk stratify patients with RBBB who were referred for stress echocardiography. The study population was comprised of 343 patients (267 men; age 66 ± 9 years) with RBBB who underwent pharmacologic stress echocardiography (231 dipyridamole, 112 dobutamine) for evaluation of suspected or known coronary artery disease. Overall mortality was the only end point. Stress echocardiography was positive for ischemia in 109 patients (32%). During follow-up (38 ± 32 months), 36 deaths occurred. Seventy-three patients underwent revascularization and were censored. Ischemia at stress echocardiography (hazard ratio [HR] 2.9, 95% confidence interval [CI] 1.5 to 5.5, P = 0.002), left anterior fascicular block (LAFB) (HR 2.8, 95% CI 1.4 to 5.6, P = 0.002), age>65 years (HR 2.1, 95% CI 1.0 to 4.3, P = 0.047), and wall motion score index at rest (HR 2.5, 95% CI 1.0 to 6.5, P = 0.057) were multivariate predictors of mortality. On the basis of stress echocardiographic result and presence and/or absence of LAFB, 3 levels of risk were identified: (1) low-risk, in cases of no ischemia and no LAFB (49% of the entire study population); (2) intermediate-risk, in cases of ischemia or LAFB only; and (3) high-risk, in cases of ischemia and LAFB. Clinical data, electrocardiography at rest, and stress echocardiographic results can provide effective stratification of risk in patients with RBBB.