[The Clinical use of Stress Echocardiography in Ischemic Heart Disease Cardiovascular Ultrasound (2017)15:7. Translation authors: Arystan A.Zh., Fettser D.V.]

Stress echocardiography is an established technique for the assessment of extent and severity of coronary artery disease. The combination of echocardiography with a physical, pharmacological or electrical stress allows detecting myocardial ischemia with an excellent accuracy. A transient worsening of regional function during stress is the hallmark of inducible ischemia. Stress echocardiography provides similar diagnostic and prognostic accuracy as radionuclide stress perfusion imaging or magnetic resonance, but at a substantially lower cost, without environmental impact, and with no biohazards for the patient and the physician. The evidence on its clinical impact has been collected over 35 years, based on solid experimental, pathophysiological, technological and clinical foundations. There is the need to implement the combination of wall motion and coronary flow reserve, assessed in the left anterior descending artery, into a single test. The improvement of technology and in imaging quality will make this approach more and more feasible. The future issues in stress echo will be the possibility of obtaining quantitative information translating the current qualitative assessment of regional wall motion into a number. The next challenge for stress echocardiography is to overcome its main weaknesses: dependence on operator expertise, the lack of outcome data (a widespread problem in clinical imaging) to document the improvement of patient outcomes. This paper summarizes the main indications for the clinical applications of stress echocardiography to ischemic heart disease.

From endothelial dysfunction to atherosclerosis.

It has recently emerged that endothelial dysfunction is an early step in the development of atherosclerosis and is mainly characterised by a reduction in the bioavailability of nitric oxide. All of the traditional cardiovascular (CV) risk factors (dyslipidemia, arterial hypertension, hyperglycemia and diabetes) are associated with endothelial dysfunction, and oxidised low-density lipoproteins, the renin-angiotensin axis and insulin resistance play important roles in the pathogenesis of impaired endothelial function. The increased expression of adhesion molecules and pro-inflammatory cytokines leads to abnormal endothelium-dependent vasodilation which could be investigated using vasoreactivity tests such as flow-mediated dilation in the brachial artery. Recently, new evidences showed that the immune system plays an important role in the pathogenesis of endothelial dysfunction and atherosclerosis with a particular regard towards autoimmunity. The high prevalence of the atherosclerotic process in systemic autoimmune diseases supports the hypothesis of the immune pathogenesis. Evaluating coronary microvascular dysfunction by means of transthoracic echocardiography with non-invasive coronary flow reserve assessment is particularly interesting as it could detect preclinical impairment of coronary microvascular function. The discovery that the mechanisms responsible for endothelial damage have a genetic basis could improve the approach to CV diseases. This review summarises the most important aspects of the pathogenesis and development of endothelial dysfunction, with particular attention to the role of traditional CV risk factors, the usefulness of vasoreactivity tests, and the future perspectives opened by genetic studies.

Prognostic correlates of combined coronary flow reserve assessment on left anterior descending and right coronary artery in patients with negative stress echocardiography by wall motion criteria.

AIMS: To assess the prognostic correlates of Doppler echocardiographically derived coronary flow reserve (CFR) on two coronaries in patients with negative stress echo. Vasodilator stress echocardiography allows dual imaging of regional wall motion and CFR both on left anterior descending (LAD) and right coronary artery (RCA). METHODS: The study group comprised 460 patients with known or suspected coronary artery disease and negative stress echo by wall motion criteria. All underwent dipyridamole (up to 0.84 mg/kg over 6 minutes) stress echo with CFR evaluation of either LAD or RCA by Doppler, and were followed up for a median of 32 months. A CFR value of < or =2.0 was taken as abnormal. RESULTS: CFR was abnormal in 174 patients (38%) (57 in LAD only, 48 in RCA only, and 69 in both LAD and RCA) and normal in 286 patients (62%). During follow-up, there were 77 cardiac events: 5 deaths, 44 acute coronary syndromes (6 STEMI, and 38 NSTEMI) and 28 late (>6 months from stress echo) revascularisations. CFR of < or =2.0 on LAD was the strongest multivariable predictor of either definite (death, acute coronary syndrome) and major (death, acute coronary syndrome, late revascularisation) events, followed by diabetes mellitus. Anti-ischaemic therapy at the time of testing and resting wall motion abnormality were also independently associated with major events. Preserved CFR in both LAD and RCA was associated with better (p<0.0001) definite and major event-free survival compared to abnormal CFR in one or both coronary vessels. CONCLUSION: CFR evaluation of either LAD or RCA allows the identification of distinct prognostic patterns. In particular, preserved CFR in both coronary vessels is highly predictive of a very favourable outcome, while reduced CFR in either coronary vessel, and especially on LAD, is a strong predictor of future cardiac events.

The additive prognostic value of end-systolic pressure-volume relation in patients with diabetes mellitus having negative dobutamine stress echocardiography by wall motion criteria.

BACKGROUND/OBJECTIVE: The end-systolic pressure-volume relation (ESPVR) is a useful method to assess left ventricular contractility during stress providing prognostic information above and beyond regional wall motion. The aim of the study was to assess the prognostic value of ESPVR in patients with diabetes mellitus having negative dobutamine stress echocardiography by wall motion criteria. DESIGN: We enrolled 233 patients with diabetes mellitus (140 males; mean age 67 (SD 9); mean ejection fraction 52 (SD 10)) having negative dobutamine (up to 40 microg/kg/min with atropine 1 mg) stress echocardiography. In all, ESPVR was determined at rest and at the peak of stress as the ratio of peak systolic pressure and end-systolic volume (SP/ESV) index. SETTING: Adult patients with diabetes mellitus evaluated at a tertiary care centre. MAIN OUTCOME MEASURES: Death, non-fatal ST-elevation (STEMI), non-ST-elevation (NSTEMI) and late (>6 months) revascularisation. RESULTS: During a median of 18 months, 62 events occurred: 35 deaths, 4 STEMI, 5 NSTEMI and 18 late revascularisations. Event-free survival was lower (p = 0.006) in patients with peak SP/ESV index < or =28 mm Hg/ml/m(2), chosen with a receiver-operating characteristic curve. Multivariable indicators of future events were prior angioplasty (HR 2.10, 95% CI 1.17 to 3.77; p = 0.01), resting wall motion abnormality (HR 1.94, 95% CI 1.12 to 3.36; p = 0.02), and peak SP/ESV index < or =28 mm Hg/ml/m(2) (HR 2.28, 95% CI 1.08 to 4.81; p = 0.03). At incremental analysis, peak SP/ESV index < or =28 mm Hg/ml/m(2) added prognostic information to that of clinical and resting echo findings. CONCLUSIONS: Patients with diabetes mellitus having negative dobutamine stress echocardiography may still experience an adverse outcome, which can be identified by ESPRV, providing a prognostic stratification in addition to that supplied by regional wall motion abnormalities.

Pre-discharge stress echocardiography and exercise ECG for risk stratification after uncomplicated acute myocardial infarction: results of the COSTAMI-II (cost of strategies after myocardial infarction) trial.

OBJECTIVE: To compare in a prospective, randomised, multicentre trial the relative merits of pre-discharge exercise ECG and early pharmacological stress echocardiography concerning risk stratification and costs of treating patients with uncomplicated acute myocardial infarction. DESIGN: 262 patients from six participating centres with a recent uncomplicated myocardial infarction were randomly assigned to early (day 3-5) pharmacological stress echocardiography (n = 132) or conventional pre-discharge (day 7-9) maximum symptom limited exercise ECG (n = 130). RESULTS: No complication occurred during either stress echocardiography or exercise ECG. At one year follow up there were 26 events (1 death, 5 non-fatal reinfarctions, 20 patients with unstable angina requiring hospitalisation) in patients randomly assigned to early stress echocardiography and 18 events (2 reinfarctions, 16 unstable angina requiring hospitalisation) in the group randomly assigned to exercise ECG (not significant). The negative predictive value was 92% for stress echocardiography and 88% for exercise ECG (not significant). Total costs of the two strategies were similar (not significant). CONCLUSION: Early pharmacological stress echocardiography and conventional pre-discharge symptom limited exercise ECG have similar clinical outcome and costs after uncomplicated infarction. Early pharmacological stress echocardiography should be considered a valid alternative even for patients with interpretable baseline ECG who can exercise.

Prognostic and clinical correlates of angiographically diffuse non-obstructive coronary lesions.

OBJECTIVE: To make a prospective assessment of the clinical and prognostic correlates of angiographically diffuse non-obstructive coronary lesions. DESIGN: Angiographic vessel and extent scores were calculated in 228 clinically stable patients (mean (SD) age, 60 (11) years; 43 women, 185 men) undergoing prospective follow up for the composite end point of death and myocardial infarction. The effect on outcome of clinical variables (age, sex, previous myocardial infarction, diabetes mellitus, smoking habit, systemic hypertension, hypercholesterolaemia, ejection fraction) and angiographic variables (vessel and extent score) was evaluated by Cox's proportion hazard model. RESULTS: The vessel score was 3 in 34 patients (15%), 2 in 78 (34%), 1 in 87 (38%), and 0 in 29 (13%). Median extent score was 60 (range 6-110; first quartile 40, third quartile 70). Forty one events (nine deaths and 32 myocardial infarcts) occurred over a median follow up period of 30 months. Age and extent score were the only multivariate predictors of outcome, but the latter provided 28% additional prognostic information after adjustment for the most predictive variables (gain in chi2 = 7, p < 0.01). A vessel score of 3 was associated with worse survival, while no significant discrimination was possible among the other groups. However, assignment of patients to two groups according to an ROC curve derived cut off value for the extent score made it possible to obtain significant discrimination of survival even in cases with vessel scores of 0 to 2. Age and diabetes were clinical markers of a higher extent score. CONCLUSIONS: The angiographic extent score is a powerful marker of adverse outcome independent of severity and the number of flow limiting coronary lesions, and may reflect the link between clinical risk profile and diffusion of coronary atherosclerosis. Thus it should be of clinical value for targeting aggressive preventive measures.

Vasodilator stress echocardiography for risk stratification of medically stabilized unstable angina.

AIMS: The aims of this study were to assess the safety, feasibility and prognostic value of dipyridamole-atropine stress echo in patients with medically stabilized unstable angina. METHODS: The initial population consisted of 173 patients consecutively admitted at two different Coronary Care Units with class IIIB unstable angina. Of these, 56 were excluded: five had poor acoustic window, 24 did not stabilize with medical therapy and underwent urgent coronary angiography, 26 evolved in non-Q wave myocardial infarction and one patient died. The remaining 117 patients underwent dipyridamole-atropine stress echo after 48 h without symptoms or electrocardiographic evidence of myocardial ischaemia. RESULTS: No complications or side effects occurred. An ischaemic response was found in 61 patients. During follow-up (10+/-9 months), three cardiac deaths, eight infarctions, 13 unstable anginas, and seven late (>3 months from stress testing) revascularizations occurred. There were 22 events (36%) in patients with, and nine events (16%) in patients without, inducible ischaemia (P=0.01). At Cox analysis peak-stress wall-motion score index (HR=5.5; 95% CI, 1.9 to 15.5; P=0.0015), and admission ST-segment depression (HR=4.2; 95% CI, 1.7 to 10.7; P=0.0022) were independent predictors of spontaneous events (cardiac death, infarction, unstable angina). The 12-month event-free survival was 69% for ischaemic and 83% for non-ischaemic group (P=0.03). In considering major events as end-points (spontaneous events, and late revascularization), again multivariate prognostic indicators were peak-stress wall-motion score index (HR=14.2; 95% CI, 2.6 to 76.6; P=0.0021), and admission ST-segment depression (HR=3.1; 95% CI, 1.4 to 6.9; P=0.0055). The 12-month event-free survival rate was 58% for ischaemic and 81% for non-ischaemic group (P=0.002). With an interactive stepwise procedure, stress echo findings were found to provide incremental prognostic contribution to that of clinical data alone. CONCLUSIONS: With proper selection of patients, dipyridamole-atropine stress echo is extremely safe and feasible in patients with medically stabilized unstable angina, and can be useful in identification of subjects at risk for future cardiac events.

Prognostic significance of the dobutamine echocardiography test in idiopathic dilated cardiomyopathy.

Dobutamine stress echo provides potentially useful information on idiopathic dilated cardiomyopathy (IDC). From February 1, 1997, to October 1, 1999, 186 patients (131 men and 55 women, mean age 56 +/- 12 years) with IDC, ejection fraction <35%, and angiographically normal coronary arteries were studied by high-dose (up to 40 micro/kg/min) dobutamine echo in 6 centers, all quality controlled for stress echo reading. In all patients, wall motion score index (WMSI) (from 1 = normal to 4 = dyskinetic in a 16- segment model of the left ventricle) was evaluated by echo at baseline and peak dobutamine. One hundred eighty-four patients were followed up (mean 15 +/- 13 months) and only cardiac death was considered as an end point. There were 29 cardiac deaths. Significant parameters for survival prediction at univariate analysis are: DeltaWMSI (chi-square 20.1; p <0.0000), New York Heart Association (NYHA) class (chi-square 17.57; p <0.0000), rest ejection fraction (chi-square 10.41; p = 0.0013), angiotensin-converting enzyme inhibitors (chi-square 8.23; p = 0.0041), and hypertension (chi-square 8.08, p = 0.0045). In the multivariate stepwise analysis only DeltaWMSI and NYHA were independent predictors of outcome (DeltaWMSI = hazard ratio 0.02, p < 0.0000; NYHA class = hazard ratio 3.83, p < 0.0000). Kaplan-Meier survival estimates showed a better outcome for patients with a large inotropic response (DeltaWMSI > or =0.44, a cutoff identified by receiver-operating characteristic curves analysis) than for those with a small or no myocardial inotropic response to dobutamine (93.6% vs 69.4%, p = 0.00033). Thus, in patients with IDC, an extensive contractile reserve identified by high-dose dobutamine stress echocardiography is associated with a better survival.

Clinical and angiographic correlates of dobutamine-induced wall motion patterns after myocardial infarction.

The ability of different dobutamine-induced wall motion patterns to define the anatomic status of the infarct-related artery (IRA) was evaluated in 159 patients who underwent dobutamine stress echocardiography (DSE) and coronary angiography 10 +/- 2 and 18 +/- 3 days, respectively, after hospital admission. The DSE result was classified as: (1) biphasic: improvement with a low dose followed by deterioration with a high dose; (2) worsening: direct deterioration at low or high doses; (3) sustained improvement: improvement with a low dose that was maintained at high dose; and (4) no change: no change during the entire protocol. A diameter narrowing >70% (50% for the left main stem) of major coronary arteries indicated a severe lesion. Angiograms were classified according to the jeopardy score and collateral circulation graded according to Rentrop's classification. DSE was positive in 92 patients (22 had biphasic results and 70 had worsening results) and negative in 67 patients (14 had sustained improvement and 53 had no changes). Biphasic response was associated with more frequent anterior infarction (p <0.05) and higher resting (p <0.001) and peak (p <0.01) wall motion score indexes. The IRA was totally occluded in 4 of the 92 patients (4%) with positive (worsening pattern) and 12 of the 67 patients (18%) with negative (no change pattern) tests. The biphasic pattern was associated with the highest jeopardy score and was significantly (p <0.05) more specific (100%) compared with worsening (78%) in identifying a severe stenosis of the IRA. The combination of ischemic patterns provided a significantly superior sensitivity (p <0.0001). Logistic regression analysis identified the biphasic pattern as the only significant predictor. Conversely, the prediction of total occlusion of the IRA was poor. Sustained improvement was the most specific (100%) predictor of absence of severe stenosis of the IRA, whereas the combination with no change pattern provided a significantly superior sensitivity (p <0.0001). Thus, DSE effectively predicts the residual stenosis of the IRA. In particular, the biphasic response has an excellent specificity and positive predictive value and is the only significant predictor among clinical and echocardiographic variables.

Angiographic and prognostic correlates of cardiac output by cardiopulmonary exercise testing in patients with anterior myocardial infarction.

STUDY OBJECTIVE: To assess the diagnostic and prognostic value of cardiac output assessed by cardiopulmonary exercise testing in patients with anterior acute myocardial infarction (AMI) and left ventricular dysfunction. PATIENTS AND SETTING: Forty-six patients with AMI (7 female patients; mean +/- SD age, 55 +/- 8 years; ejection fraction, 39 +/- 7%) underwent cardiopulmonary exercise testing and coronary angiography following hospital discharge. MEASUREMENT AND RESULTS: Cardiac output was estimated from oxygen uptake (VO(2)) during exercise according to a method based on the linear regression between arteriovenous oxygen content difference and percent maximum VO(2). Angiograms were scored using Gensini and Duke "jeopardy" scores. Cardiac output at anaerobic threshold (COAT) < or = 7.3 L/min was the best cutoff value for identifying multivessel coronary artery disease (relative risk, 3.1). Angiographic scores were significantly higher in patients with COAT < 7.3 L/min as compared to those with COAT > 7.3 L/min (82 +/- 8 vs 53 +/- 7 and 6 +/- 2 vs 4 +/- 3, respectively; p < 0.05) and were inversely and significantly correlated to COAT. Conversely, no correlation was found with ECG changes. COAT, VO(2) at anaerobic threshold, and peak VO(2) were univariate prognostic indicators. However, using Cox's model, COAT was the only multivariate predictor of outcome (odds ratio, 0.28; 95% confidence interval [CI], 0.09 to 0.9). Moreover, COAT < 7.3 L/min was associated to an increased risk of further cardiac events (odds ratio, 5; 95% CI, 1.4 to 17) and provided a significant discrimination of survival for the combined end point of cardiac death, reinfarction, and clinically driven revascularization. CONCLUSIONS: COAT is a safe and feasible tool providing additional diagnostic and prognostic information in patients with AMI.

Stress echocardiography for risk stratification of diabetic patients with known or suspected coronary artery disease.

OBJECTIVE: Coronary artery disease (CAD) is a leading cause of mortality and morbidity in diabetic patients; therefore, their risk stratification is a relevant issue. Because exercise tolerance is frequently impaired in these patients, pharmacological stress echocardiography (SE) has been suggested as a valuable alternative. Our aim was to evaluate the prognostic value of this technique in diabetic patients with known or suspected CAD. RESEARCH DESIGN AND METHODS: A total of 259 consecutive diabetic patients underwent pharmacological SE (dobutamine in 108 patients and dipyridamole in 151 patients) and follow-up for 24 +/- 22 months. A comparison between the prognostic value of SE and exercise electrocardiography (ECG) was made in a subgroup of 120 subjects. RESULTS: A total of 13 cardiac deaths and 13 nonfatal infarctions occurred during follow-up, and 58 patients were revascularized. Univariate predictors of outcome were known CAD, positive SE, rest and peak wall motion score index (WMSI), and peak/rest WMSI variation. Peak WMSI was the only significant and independent prognostic indicator (odds ratio 11; 95% CI 4-29, P < 0.0001) on multivariate Cox's analysis. After adjustment for the most predictive clinical and exercise ECG variables, SE provided 43% additional prognostic information (gain in X(2) = 7, P < 0.01). Moreover, positive SE was associated with a significantly lower event-free survival. CONCLUSIONS: SE effectively predicts cardiac events in diabetic patients with known or suspected CAD and adds additional prognostic information as compared with exercise ECG.

The prognostic value of myocardial viability recognized by low dose dipyridamole echocardiography in patients with chronic ischaemic left ventricular dysfunction.

AIMS: The aim of this study was to assess the prognostic value of myocardial viability recognized as a contractile response to vasodilator stimulation in patients with left ventricular dysfunction in a large scale, prospective, multicentre, observational study. METHODS AND RESULTS: Three hundred and seven patients (mean age 60 +/- 10 years) with angiographically proven coronary artery disease, previous (>3 months) myocardial infarction and severe left ventricular dysfunction (ejection fraction <35%; mean ejection fraction: 28 +/- 7%) were enrolled in the study. Each patient underwent low dose dipyridamole echo (0.28 mg x kg(-1) in 4 min). Myocardial viability was identified as an improvement of >0.20 in the wall motion score index. By selection, all patients were followed up for a median of 36 months. One-hundred and twenty-four were revascularized either by coronary artery bypass grafting (n=83) or coronary angioplasty (n=41). The only end-point analysed was cardiac death. In the revascularized group, cardiac death occurred in one of the 41 patients with and in 16 of the 83 patients without a viable myocardium (2.4% vs 19.3%, P<0.01). Outcome, as estimated by Kaplan-Meier survival, was better for patients with, compared to patients without, a viable myocardium, who underwent coronary revascularization (97.6 vs 77.4%, P=0.01). Using a Cox proportional hazards model, the presence of myocardial viability was shown to exert a protective effect on survival (chi-square 4.6, hazard ratio 0.1, 95% CI 0.01-0.8, P<0.03). The survival rate in medically treated patients was lower than in revascularized patients irrespective of the presence of a viable myocardium (79.7% vs 86.2, P=ns). CONCLUSION: In severe left ventricular ischaemic dysfunction, myocardial viability, as assessed by low dose dipyridamole echo, is associated with improved survival in revascularized patients.

Noninvasive assessment of coronary artery disease: the role of stress echocardiography.

Echocardiography combined with either exercise or pharmacological stress is a widely used method for the noninvasive assessment of coronary artery disease. This is due to the high diagnostic accuracy that does not differ substantially among the various stress modalities. In addition, stress echocardiography has a useful role in risk stratification of patients with known or suspected coronary artery disease. In particular, evidence of inducible ischemia is predictive of an unfavorable outcome, whilst its absence is associated with a very low risk of future cardiac events. These findings have strong implications in clinical decision-making. One of the main characteristics of the echographic marker of ischemia is that it is significantly more specific than the electrocardiographic one. The higher specificity of stress echocardiography translates into increased prognostic value as compared to exercise electrocardiography. Nevertheless, exercise electrocardiography has a very high negative predictive value. Moreover, compared to stress echocardiography it is safer, simpler, less costly and requires no specific competence. Based on these data, exercise electrocardiography remains the cornerstone of the noninvasive evaluation of coronary artery disease. Stress echocardiography, on the other hand, is particularly useful in those cases when exercise electrocardiography is not feasible, non-interpretable (owing to the presence of left bundle branch block or of a pacemaker or of other electrocardiographic baseline abnormalities), or when it gives inconclusive data, or a positive result at an intermediate or high workload (in such cases, precise knowledge of the site and extension of ischemia can be of crucial importance in deciding between conservative and aggressive treatment), as well as in cases in which ischemia during the test is frequently a false positive response, as in hypertensive patients, in women and in all cases of left ventricular hypertrophy.

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.

Safety, feasibility, and prognostic implications of pharmacologic stress echocardiography in 1482 patients evaluated in an ambulatory setting.

BACKGROUND: The outpatient prognostic assessment of coronary artery disease (CAD) by exercise electrocardiography has limitations, including the feasibility of the test and its low positive predictive value in several clinical conditions. In the current study we investigated the safety, feasibility, and prognostic value of pharmacologic stress echocardiography in a large cohort of ambulatory patients. METHODS: The study group was made of 1482 ambulatory patients (969 men, aged 60 +/- 10 years) who underwent stress echocardiography with either dipyridamole (n = 846) or dobutamine (n = 636) for evaluation of suspected or known stable CAD. The pretest likelihood of CAD was intermediate (<70%) in 709 patients and high (> or =70%) in 773 patients. RESULTS: There was no complication during the dipyridamole test, whereas 2 ischemia-dependent, sustained ventricular tachycardias occurred during the dobutamine test. Limiting side effects were observed in 2% of dipyridamole and in 3% of dobutamine stresses. The echocardiogram was positive in 459 patients. During a mean follow-up of 28 +/- 24 months, 58 patients died, 33 had a nonfatal myocardial infarction, and 158 underwent early (< or =3 months) and 64 late (>3 months) revascularization. Multivariate predictors of hard events (death, infarction) were positive echocardiographic results (hazard ratio [HR] 2.9) and resting wall motion score index (WMSI) (HR 2.3). In considering major events (death, infarction, late revascularization) as end points, positive echocardiographic result (HR 4.3), scar (HR 2.2), and resting WMSI (HR 1.7) were independent prognostic predictors. The 5-year survival rates for the ischemic and nonischemic groups were, respectively, 80% and 91% (HR 3.6, 95% confidence interval [CI] 3.8-8.4; P <.0001) considering hard cardiac events and 65% and 88% (HR 2.6, 95% CI 2.1-5.9; P <.0001) considering major events. Multivariate predictors of major events were positive echocardiographic results (HR 8.2) and male sex (HR 2.5) for the intermediate-risk group and positive echocardiographic results (HR 2.9), resting WMSI (HR 1.8), and prior Q-wave myocardial infarction (HR 1.8) for the high-risk group. CONCLUSIONS: Pharmacologic stress echocardiography is safe, highly feasible, and effective in prognostic assessment of ambulatory patients when both a general population and groups selected on the basis of pretest likelihood of CAD are analyzed. It represents a valid complementary tool to exercise electrocardiography for prognostic purposes in outpatients.

[Effectiveness and adequacy of management of acute coronary syndromes]. / Efficacia e appropriatezza nella gestione delle sindromi coronariche acute.

A rational utilization of resources represents a key issue in modern treatment of cardiac patients. The aim of our study was to highlight a few essential aspects for an efficient and appropriate management of patients with an acute coronary syndrome. Clinical evaluation of the patient's risk (i.e. clinical assessment of the probability of developing a cardiac event), incremental value of the chosen test for risk stratification, value of a strategy in modifying outcome and direct determinants of medical cost of the strategy are selected as the main aspects to be considered in order to optimize management of these patients.