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Objectives. This study sought to verify the effectiveness of pharmacologic stress echocardiography in risk stratification of patients with single-vessel disease. Background. Noninvasive prognostic assessment of single-vessel disease is an unresolved issue to date. Methods. The study evaluated prospectively collected data from 754 patients with angiographic single-vessel disease who underwent either dipyridamole (n = 576) or dobutamine (n = 178) stress echocardiography. Invasive treatment (coronary revascularization within 3 months of stress testing) was performed in 260 patients and medical treatment in 494. Results. Echocardiographic positivity was observed in 421 patients (56%). Patients treated invasively had a higher incidence of stress test positivity (69% vs. 49%, p < 0.001) and left anterior descending coronary artery involvement (60% vs. 46%, p < 0.001) than patients maintained with medical therapy. During a mean follow-up of 37 months, 54 hard cardiac events occurred (14 deaths, 40 nonfatal infarctions): 37 in medically and 17 in invasively treated patients (7.5% vs. 6.5%, p = NS). On Cox analysis, a positive result on stress testing was the only independent prognostic predictor in medically treated patients (relative risk 2.92, 95% confidence interval 1.29 to 6.59). The 4-year infarction-free survival rate was higher for a negative than a positive stress test result in medically (93.9% vs. 87.3%, p = 0.009) but not invasively treated patients (92.7% vs. 97.1%, p = 0.545). Moreover, a significantly higher 4-year infarction-free survival rate was found in invasively versus medically treated patients with a positive (p = 0.012), but not in those with a negative, stress test result (p = 0.853). Conclusions. Pharmacologic stress echocardiography is effective in risk stratification of single-vessel disease and can accurately discriminate patients in whom coronary revascularization can have the maximal beneficial effect. These findings have a potential favorable impact on the cost-effectiveness of invasive procedures.

Objectives. We sought to assess whether the site of future myocardial infarction can be predicted on the basis of induced dyssynergy (“area at risk”) recognized by stress echocardiography. Background. The severity and extent of stress-induced dyssynergy are strong predictors of subsequent major cardiac events. However, high grade stenotic lesions are not strictly associated with the site of future coronary occlusions. Methods. From the stress echocardiography multicenter trials data bank, we selected 70 patients (56 men; mean age ± SD 58 ± 11 years) meeting the following inclusion criteria: 1) dipyridamole (n = 53) or dobutamine (n = 17) stress echocardiography; 2) a spontaneously occurring infarction, with no intercurrent revascularization procedure between the initial study and the infarction; and 3) a follow-up rest echocardiogram obtained 41 ± 90 days after the infarction. Results. A complete ischemia-infarction mismatch (infarct-related dysfunction in a patient with negative stress test results) occurred in 29 patients (41%). A partial mismatch (ischemic dysfunction in a territory different from the infarct area) occurred in nine patients (13%). A match (ischemia-related and infarction-related dyssynergy involving the same region) occurred in 32 patients (46%). The average time interval between the stress examination and the occurrence of infarction or reinfarction was 144 ± 160 days in patients with a match and 439 ± 622 days in patients with a mismatch (p < 0.05). Conclusions. Induced ischemia (imaged as transient dyssynergy by pharmacologic stress echocardiography) inconsistently identifies the site of future infarction. The majority of spontaneous coronary occlusions leading to infarction unheralded by induced ischemia. However, most infarctions occurring within 1 year of stress testing are in the area identified as ischemic during testing.

Objectives. This study sought to assess the value of dipyridamole echocardiography in predicting reinfarction in patients evaluated early after uncomplicated acute myocardial infarction. Background. The identification of future nonfatal reinfarction seems an elusive target for physiologic testing. However, a large sample population is needed to detect minor differences in phenomena with a low event rate. Methods. We assessed the value of dipyridamole echocardiography in predicting reinfarction in 1,080 patients (mean [±SD] age 56 ± 9 years; 926 men, 154 women) evaluated early (10 ± 5 days) after uncomplicated acute myocardial infarction and followed up for 14 ± 10 months. Results. Submaximal studies due to limiting side effects occurred in 14 patients (1.3%); these test results were included in the analysis. Results of dipyridamole echocardiography were positive in 475 patients (44%). During follow-up, there were 50 reinfarctions: 45 nonfatal, 5 fatal (followed by cardiac death ≤4 days after reinfarction). Reinfarction (either nonfatal or fatal) occurred in 30 patients with positive and 20 with negative results (6.3% vs. 3.3%, p Conclusions. Dipyridamole echocardiographic positivity identifies patients evaluated early after uncomplicated acute myocardial infarction at higher risk of reinfarction, especially fatal reinfarction.

Objectives. This study was conducted to assess the feasibility, safety and prognostic value of dipyridamole echocardiography in elderly patients recovering from an uncomplicated acute nyocardial infarction in a subset analysis performed on the patients entered in the subproject “residual ischemia” of the Echo Persantine Italian Cooperative Study (EPIC). Background. Coronary heart disease accounts for two thirds of all deaths in the age group >65 years, and >50% of all patients admitted to the hospital with acute myocardial infarction are >65 years old. The prognostic value of dipyridamole-induced left ventricular dysfunction was clearly established in patients evaluated early after acute infarction. Methods. In a subgroup analysis of the Echo Persantine Italian Cooperative Study (EPIC), we assessed the value of dipyridamole echocardiography in predicting cardiac events in 190 elderly (≥65 years) patients (age 68.4 ± 3.3 years, range 65 to 78; 147 men and 43 women) evaluated early (mean 10 days) after uncomplicated acute myocardial infarction and followed up for 14 ± 9.8 months. Results. There was no major side effect during dipyridamole echocardiography. A positive test result occurred in 85 patients (44.7%). During follow-up, there were 62 events (14 cardiac deaths, 7 nonfatal reinfarctions, 21 cases of class III or IV angina and 20 revascularization procedures). Of these 62 events, 44 occurred among 85 patients with positive dipyridamole echocardiography and 18 among 105 patients with negative dipyridamole echocardiography (52% vs. 17%, p < 0.001). Spontaneous events (death, reinfarction, angina) occurred in 31 patints with positive and in 11 with negative dipyridamole echocardiography (36% vs. 10%, p < 0.001). Hard events (myocardial infarction or death) occurred in 14 patients with positive and 7 with negative dipyridamole echocardiography (16% vs. 6%, p < 0.05). Death occurred in 11 patients with positive and in 3 with negative dipyridamole echocardiography (13% vs. 3%, p < 0.01). The positive predictive value of positive dipyridamole echocardiography and negative predictive value of negative dipyridamole echocardiography as related to the occurrence of all events in the follow-up period (death, reinfarction, angina, revascularization procedures) were 52% and 83%, respectively. The relative risk (that is, the relative risk of occurrence of future cardiac events in the group with positive dipyridamole echocardiography compared with that in those with negative dipyridamole echocardiography) was 3 for all events and 4.4 for death. Conclusions. Dipyridamole echocardiography was well tolerated by elderly patients and proved to be very effective in prognostic stratification early after uncomplicated acute myocardial infarction, even when only survival was considered.

Clinical data on 10,451 high-dose (up to 0.84 mg/kg over 10 minutes) dipyridamole-echocardiography tests (DET) performed in 9,122 patients were prospectively collected from 33 echocardiographic laboratories, each contributing greater than 100 tests. All patients were studied for documented or suspected coronary artery disease (1,117 early [less than 18 days] after acute myocardial infarction and 293 had unstable angina). Significant side effects including major adverse reactions and minor but limiting side effects occurred in 113 patients (1.2%). Major adverse reactions occurred in 7 cases (0.07%). In 6 of these cases, adverse reactions were associated with echocardiographically assessed ischemia and included 1 prolonged cardiac asystole (complicated by acute myocardial infarction and coma, with death after 23 days), 1 short-lasting cardiac asystole, 2 myocardial infarctions, 1 pulmonary edema and 1 sustained ventricular tachycardia. In all 6 cases, the cardiologist-echocardiographer performing the study had a limited experience (less than 100 tests) with DET, and at off-line reading in 5 cases, the obvious echo-positivity preceded the onset of complications by 1 to 5 minutes. The only ischemia-independent major side effect was a short-lasting cardiac asystole that was reversed by aminophylline and atropine. Significant side effects associated with echocardiographically assessed ischemia occurred in 89 additional cases (21 with and 68 without concomitant echocardiographically assessed myocardial ischemia). The most frequent of these side effects was hypotension or bradycardia, or both, which occurred in 40 patients with negative and 6 with positive DET. In all cases, side effects promptly subsided after aminophylline. In 1,857 cases, the high dose was not given for echo-positivity before the eighth minute.(ABSTRACT TRUNCATED AT 250 WORDS)