Prognostic value of exercise echocardiography in patients with classic angina pectoris

The role of stress echocardiography in the prognostic evaluation of patients with angina pectoris is not well defined. This study included 437 patients (241 men and 196 women) with angina pectoris and a pretest probability of coronary artery disease (CAD) of > or = 0.7 who were referred for exercise echocardiography. No patient had a history of acute myocardial infarction or coronary revascularization. Mean age was 65 +/- 10 years. During a median follow-up of 2.7 years, hard cardiac events (cardiac death or nonfatal myocardial infarction) occurred in 19 patients and 53 patients underwent coronary revascularization. Event-free survival rates in patients with normal versus abnormal stress echocardiograms were 98% versus 83% at 1 year, 96% versus 75% at 3 years, and 87% versus 69% at 5 years, respectively. In a multivariate analysis of clinical, exercise stress, and echocardiographic parameters, independent predictors of hard cardiac events were Q waves on the electrocardiogram (chi-square 8.7, p = 0.003) and the presence of wall motion abnormalities during exercise in multivessel distribution (chi-square 5.3, p = 0.02). In an incremental model of clinical, exercise, and echocardiographic variables for the prediction of all cardiac events, the addition of echocardiographic data increased the chi-square of the model from 62 to 78 (p = 0.0003). Exercise echocardiography provides useful information in the risk stratification of patients with suspected CAD and a high pretest probability of CAD. Patients with normal exercise echocardiograms have a low event rate and therefore can be exempted from invasive procedures during the 3 years after a normal exercise echocardiogram.     

Functional and prognostic significance of exercise-induced ventricular arrhythmias in patients with suspected coronary artery disease

Our aims were to assess (1) the relation between exercise-induced ventricular arrhythmia (VA) and myocardial wall motion abnormalities during exercise echocardiography in patients with suspected coronary artery disease (CAD), and (2) the effect of this relation on outcome. We studied the clinical and prognostic significance of exercise-induced VA in 1,460 patients (mean age 64 +/- 10 years; 867 men) with intermediate pretest probability of CAD and no history of previous myocardial infarction or revascularization who underwent exercise echocardiography. Exercise-induced VA occurred in 146 patients (10%). Compared with patients without VA, those with VA had a greater prevalence of abnormal exercise echocardiographic findings (48% vs 29%, p = 0.001) and ischemia on exercise echocardiography (39% vs 22%, p = 0.001), greater increase in wall motion score index with exercise (0.14 +/- 0.28 vs 0.06 +/- 0.18, p <0.0001), and a greater percentage of abnormal segments with exercise (21 +/- 30% vs 9 +/- 19%, p <0.0001). During follow-up (median 2.7 years), cardiac death and nonfatal myocardial infarction occurred in 36 patients. In multivariate analysis of combined clinical and exercise stress test variables, independent predictors of cardiac events were exercise-induced VA (chi-square 4.7, p = 0.03) and exercise heart rate (chi-square 18, p = 0.0001). The percentage of abnormal myocardial segments with exercise echocardiography was the most powerful predictor of VA (chi-square 31, p = 0.0001) and cardiac events (chi-square 15, p = 0.0001). In patients with suspected CAD, exercise-induced VA is associated with a greater risk of cardiac death and nonfatal myocardial infarction. This risk is attributed to the relation between VA and the extent and severity of left ventricular functional abnormalities with exercise.     

Outcome After Normal Exercise Echocardiography and Predictors of Subsequent Cardiac Events: Follow-Up of 1,325 Patients

Objectives. This study sought to examine the outcome of a large group of patients after normal exercise echocardiography and to identify potential predictors of subsequent cardiac events.Background. Earlier studies suggested that prognosis after normal exercise echocardiography is favorable, with a low subsequent cardiac event rate. These studies involved a small number of patients and did not have sufficient statistical power to stratify risk.Methods. The outcomes of 1,325 patients who had normal exercise echocardiograms were examined. End points were overall and cardiac event-free survival. Cardiac events were defined as cardiac death, nonfatal myocardial infarction and coronary revascularization. Patient characteristics were analyzed in relation to time to first cardiac event in a univariate and multivariate manner to determine which, if any, were associated with an increased hazard of subsequent cardiac events.Results. Overall survival of the study group was significantly better than that of an age- and gender-matched group obtained from life tables (p < 0.0001). The cardiac event-free survival rates at 1, 2 and 3 years were 99.2%, 97.8% and 97.4%, respectively. The cardiac event rate per person-year of follow-up was 0.9%. Subgroups with an intermediate or high pretest probability of having coronary artery disease also had low cardiac event rates. Multivariate predictors of subsequent cardiac events were angina during treadmill exercise testing (risk ratio [RR] 4.1, 95% confidence interval [CI] 1.5 to 11.0), low work load (defined as <7 metabolic equivalents [METs] for men and <5 METs for women; RR 3.2, 95% CI 1.4 to 7.6), echocardiographic left ventricular hypertrophy (RR 2.6, 95% CI 1.1 to 6.3) and advancing age (RR 1.04/year, 95% CI 1.0 to 1.1).Conclusions. The outcome after normal exercise echocardiography is excellent. Subgroups with an intermediate or high pretest probability of having coronary artery disease also have a favorable prognosis after a normal exercise echocardiogram. Characteristics predictive of subsequent cardiac events (i.e., patient age, work load, angina during exercise testing and echocardiographic left ventricular hypertrophy) should be considered in the clinical interpretation of a normal exercise echocardiogram.     

Prediction of mortality in patients with left ventricular hypertrophy by clinical,exercise stress,and echocardiographic data

OBJECTIVES: This study evaluated the clinical, exercise stress test, and echocardiographic predictors of mortality and cardiac events in patients with left ventricular hypertrophy (LVH). BACKGROUND: Left ventricular hypertrophy is associated with an increased risk of cardiovascular morbidity and mortality. METHODS: Symptom-limited treadmill exercise echocardiography was performed for evaluation of coronary artery disease in 483 patients (age, 66 +/- 11 years; 281 men) with LVH. End points during follow-up were all-cause mortality and hard cardiac events (cardiac death and nonfatal myocardial infarction [MI]). RESULTS: Forty-six patients died and 14 had nonfatal MI. The cumulative mortality rate was higher in patients with abnormal exercise echocardiography (3% vs. 0.4% at one year, 11.7% vs. 3.7% at three years, and 18.3% vs. 9.5% at five years, p < 0.001). In a sequential multivariate analysis model of clinical, exercise test, and rest and exercise echocardiographic data, incremental predictors of mortality were workload (hazard ratio [HR], 0.5; 95% confidence interval [CI], 0.3 to 0.9), rate pressure product (HR, 0.7; 95% CI, 0.5 to 0.9), left ventricular (LV) mass index (HR, 1.4; 95% CI, 1.1 to 1.8), and failure to increase ejection fraction (EF) with exercise (HR, 2.1; 95% CI, 1.1 to 3.8). Predictors of cardiac events were history of coronary artery bypass grafting (HR, 2.6; 95% CI, 1.2 to 5.4), lower exercise rate-pressure product (HR, 0.6; 95% CI, 0.5 to 0.8), resting wall motion score index (HR, 1.4; 95% CI, 1.1 to 1.8), and failure to increase EF with exercise (HR, 3.3; 95% CI, 1.6 to 6.9). CONCLUSIONS: In patients with LVH, LV mass index and EF response to exercise are independent predictors of mortality, incremental to clinical and exercise test data and resting LV function. A normal exercise echocardiogram predicts a relatively low mortality rate during the following three years.     

Prognostic significance of the location of wall motion abnormalities during exercise echocardiography

OBJECTIVES: Our aim was to determine whether location of wall motion abnormalities (WMAs) during exercise echocardiography provides independent prognostic value. BACKGROUND: The effect of the location of WMAs during stress echocardiography on prognostic outcome is unknown. METHODS: We studied 4,347 patients (mean age, 61 +/- 12 years; 2,230 men) with known or suspected coronary artery disease by symptom-limited exercise echocardiography. An abnormal result was defined as resting or exercise-induced WMA. End points were cardiac death and nonfatal myocardial infarction (MI). RESULTS: There were 133 cardiac events (54 cardiac deaths and 79 nonfatal MIs) during follow-up (median, three years). In a multiple-stepwise multivariate analysis model, clinical and exercise electrocardiography predictors of cardiac events were age, gender, hypertension, typical chest pain, previous MI, smoking, and resting ejection fraction. The percentage of ischemic segments at peak exercise provided additional information to the model (p = 0.0001). The presence of abnormalities in the left anterior descending (LAD) coronary artery distribution had an additional independent effect for the prediction of cardiac events (p = 0.001). Among patients with exercise echocardiographic abnormalities in a single vascular region, those with abnormalities in the left anterior descending coronary artery distribution had a higher event rate than patients with abnormalities elsewhere (3.2% vs. 2.1% at three years and 10.8% vs. 2.1% at five years; p = 0.009). CONCLUSIONS; Exercise WMAs in the distribution of the LAD coronary artery are associated with an increased risk of cardiac death and nonfatal MI. This risk is independent of the resting ejection fraction and the extent of WMAs during exercise.     

Risk stratification by treadmill exercise echocardiography in patients with excellent exercise capacity

BACKGROUND: The incremental value of exercise echocardiography (EE) has been demonstrated to be maximal in patients with moderate pretest probability for coronary artery disease, but there is a lack of data in patients with low pretest probability or patients with good functional capacity. METHODS: To investigate whether such incremental value is maintained in patients with excellent exercise capacity, we studied 1,433 patients who had excellent exercise capacity (>or=8 METs for women, >or=10 METs for men). RESULTS: During a follow-up of 2.3 +/- 1.5 years, 42 hard events occurred (cardiac death or nonfatal myocardial infarction). Variables independently associated to hard events were male gender (P = 0.04), % of the age-predicted maximum heart rate (P = 0.02), chronotropic reserve (P = 0.002), and abnormal EE (P = 0.03; incremental P value of EE = 0.03). CONCLUSIONS: EE has incremental value over clinical variables, resting echocardiography, and exercise testing variables in patients with excellent exercise capacity. EE may be preferable to ECG exercise testing even in patients expected to have good exercise capacity.     

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.     

Prognostic implications of a negative dipyridamole-thallium scan: results in 360 patients.

PATIENTS AND METHODS: A total of 360 patients with either normal perfusion (314) or fixed defects (46) on dipyridamole-thallium scans were followed over an average period of 16 months. Of the 360 patients, 194 subsequently underwent major noncardiac surgery. RESULTS: There were a total of eight cardiac events including two postoperative complications (one fatal and one nonfatal myocardial infarction) and six cardiac events during long-term follow-up (one sudden death and five nonfatal infarctions). During the follow-up period, three patients underwent coronary artery bypass surgery. The low cardiac event rate could not be explained by a low pretest likelihood of coronary artery disease: 77% of the 360 patients had either typical angina pectoris, a previous myocardial infarction, or peripheral vascular disease, which is associated with a high prevalence of coronary artery disease. CONCLUSIONS: In patients with a high pretest likelihood of coronary artery disease, the absence of thallium redistribution on a dipyridamole-thallium scan denotes a very low (1%) cardiac risk for major noncardiac surgery as well as low long-term cardiac mortality (0.3%) and morbidity (1.4%) rates. The coronary death rate is comparable to that of patients with minimal (less than 50%) coronary stenoses.     

Prognostication of the course of stable ischemic heart disease by exercise stress echocardiography

We analyzed data from 549 patients (450 with high and 99 -- low pretest probability of ischemic events). Duration of observation was 12-42 (mean 20.1+/-11.6) months. End points were death, nonfatal myocardial infarction, and revascularization. Cox proportional hazards model was used for assessment of relationship between clinical-instrumental data and events. One year risk of cardiac death and nonfatal myocardial infarction was 3 and 15%, event free survival -- 95 and 66% for patients with negative and positive result of stress echocardiography, respectively. Besides local contractility disturbances total test duration less than 6 min was significantly related to prognosis of main events while left ventricular hypertrophy, amount of METs, development of angina during stress test, and hypertensive disease were predictors of combined end point (death, nonfatal myocardial infarction, or revascularization). Thus results of exercise stress echocardiography had high prognostic power in patients with ischemic heart disease.     

Prognostic value of exercise echocardiography in patients after coronary artery bypass surgery

To assess the prognostic value of exercise echocardiography in patients with prior coronary artery bypass surgery, follow-up was obtained in 718 patients (591 men [82%] and 127 women [18%], aged 67 +/- 9 years) who underwent clinically indicated exercise echocardiography 5.7 +/- 4.7 years after coronary bypass surgery. Resting wall motion abnormalities were present in 479 patients (67%). New or worsening wall motion abnormalities developed with exercise in 366 patients (51%). During a median follow-up of 2.9 years, cardiac events included cardiac death in 36 patients and nonfatal myocardial infarction in 40 patients. The addition of the exercise echocardiographic variables, abnormal left ventricular end-systolic volume response and exercise ejection fraction to the clinical, resting echocardiographic and exercise electrocardiographic model provided incremental information in predicting cardiac events (chi-square 37 to chi-square 42, p = 0.02) and cardiac death (chi-square 38 to chi-square 43, p <0.02). Exercise echocardiography provides prognostic information in patients after coronary artery bypass surgery, incremental to clinical, rest echocardiographic, and exercise electrocardiographic variables.     

Prognostic value of myocardial contrast echocardiography in patients presenting to hospital with acute chest pain and negative troponin

We hypothesized that myocardial contrast echocardiography (MCE) could be used to stratify risk in patients with suspected acute coronary syndrome but a nondiagnostic electrocardiogram and negative troponin. Pretest Thrombolysis In Myocardial Infarction (TIMI) scores were determined. Exercise electrocardiographic data in those patients undergoing treadmill stress echocardiography as part of risk evaluation were analyzed independently of echocardiographic data. On a separate day, low-power MCE at rest and during vasodilator stress was performed. All patients were followed for cardiac events (cardiac death, myocardial infarction, and revascularization). Of 148 patients, 27 demonstrated abnormal myocardial contrast echocardiographic results and had higher cardiac event rates compared with those with normal myocardial contrast echocardiographic findings (59% vs 7%, p <0.0001) at follow-up (8 +/- 5 months). Hard cardiac event rates (death and nonfatal myocardial infarction) were low (3%) in patients with normal myocardial contrast echocardiographic findings. Cardiac events in patients with abnormal myocardial contrast echocardiographic findings (59%) were significantly higher than those predicted by a high-risk TIMI score (33%, p = 0.0023) and compared with those predicted by high-risk exercise electrocardiography (80% vs 57%, p = 0.0003). In conclusion, stress MCE was superior to TIMI risk score and exercise electrocardiography in the assessment of risk in patients with suspected acute coronary syndrome, nondiagnostic electrocardiogram, and negative troponin.     

Prognostic value of normal myocardial radionuclide scan in patients with positive treadmill test

The purpose of this study was to determine the prognostic value of a normal 201Tl scan in patients with a positive treadmill exercise stress test. We analyzed retrospectively 85 consecutive patients with a positive treadmill exercise test and normal Tl201 scan who were studied for the diagnosis of coronary artery disease from January 1996 to December 2000. The pretest probability of coronary artery disease was intermediate or high in all patients. Seventy-eight patients (89%) were followed up for 2.03 years. Forty patients (51%) were men. Age was 56 years. The cardiac events considered were angina, revascularization, nonfatal myocardial infarction, and cardiac death. During the follow-up period, none of the patients suffered a major cardiac event. Eight patients had episodes of chest pain and one had angor that required revascularization. Patients with an intermediate probability of coronary artery disease before the test and normal myocardial radionuclide scan had a very good prognosis even with a positive treadmill exercise test.     

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.     

Stress Echocardiography and Major Cardiac Events in Patients with Normal Exercise Test

Background

Exercise test (ET) is the preferred initial noninvasive test for the diagnosis and risk stratification of coronary artery disease (CAD), however, its lower sensitivity may fail to identify patients at greater risk of adverse events.

Objective

To assess the value of stress echocardiography (SE) for predicting all-cause mortality and major cardiac events (MACE) in patients with intermediate pretest probability of CAD and a normal ET.

Methods

397 patients with intermediate CAD pretest probability, estimated by the Morise score, and normal ET who underwent SE were studied. The patients were divided into two groups according to the absence (G1) or presence (G2) of myocardial ischemia on SE .End points evaluated were all-cause mortality and MACE, defined as cardiac death and nonfatal acute myocardial infarction (AMI).

Results

G1 group was comprised of 329 (82.8%) patients. The mean age of the patients was 57.37 ± 11 years and 44.1% were male. During a mean follow-up of 75.94 ± 17.24 months, 13 patients died, three of them due to cardiac causes, and 13 patients suffered nonfatal AMI. Myocardial ischemia remained an independent predictor of MACE (HR 2.49; [CI] 95% 1.74-3.58). The independent predictors for all-cause mortality were male gender (HR 9.83; [CI] 95% 2.15-44.97) and age over 60 years (HR 4.57; [CI] 95% 1.39-15.23).

Conclusion

Positive SE for myocardial ischemia is a predictor of MACE in the studied sample, which helps to identify a subgroup of patients at higher risk of events despite having normal ET.     

Prognostic value of exercise echocardiography in 5,798 patients: is there a gender difference?

OBJECTIVES: This study was designed to determine the effect of gender on the prognostic value of exercise echocardiography. BACKGROUND: Limited information exists regarding gender differences in prognostic value of exercise echocardiography. METHODS: We obtained follow-up (3.2 +/- 1.7 years) in 5,798 consecutive patients who underwent exercise echocardiography for evaluation of known or suspected coronary artery disease. RESULTS: There were 3,322 men (mean age 62 +/- 12 years) and 2,476 women (mean age 62 +/- 12 years) (p = 0.7). New or worsening wall motion abnormalities developed with exercise in 35% of men and 25% of women (p = 0.001). Cardiac events, including cardiac death (107 patients) and nonfatal myocardial infarction (148 patients), occurred in 5.3% of men and 3.1% of women (p = 0.001). Addition of the percentage of ischemic segments to the clinical and rest echocardiographic model provided incremental information in predicting cardiac events for both men (chi(2) = 137 to 143, p = 0.014) and women (chi(2) = 72 to 76, p = 0.046). By multivariate analysis, exercise electrocardiographic and exercise echocardiographic predictors of cardiac events in both men and women were workload and exercise wall motion score index. There was no significant interaction effect of rest echocardiography (p = 0.79), exercise electrocardiography (p = 0.38) or exercise echocardiography (p = 0.67) with gender. CONCLUSIONS: Although cardiac events occurred more frequently in men, the incremental value of exercise echocardiography was comparable in both genders. Of all exercise electrocardiographic and exercise echocardiographic variables, workload and exercise wall motion score index had the strongest association with outcome. The results of exercise echocardiography have comparable implications in both men and women.     

Prognostic stratification of diabetic patients by exercise echocardiography

OBJECTIVES: The aim of this study was to assess the incremental value of exercise echocardiography for the risk stratification of diabetic patients. BACKGROUND: There are currently insufficient outcome data in diabetic patients to define the role of stress echocardiography as a prognostic tool. METHODS: We studied the prognostic value of exercise echocardiography in 563 patients with diabetes mellitus (mean age 64 +/- 11 years, 336 men) and known or suspected ischemic heart disease (IHD). RESULTS: Cardiac events occurred in 50 patients (cardiac death in 23 and nonfatal myocardial infarction [MI] in 27) during a median follow-up period of three years. Event rate was lower in patients with normal as compared to those with abnormal exercise echocardiography at one year (0% vs. 1.9%), three years (1.8% vs. 11.9%), and five years (7.6% vs. 23.3%), respectively (p = 0.0001). Patients with multivessel distribution of echocardiographic abnormalities had the highest event rate (2.9% at one year, 15.2% at three years, and 32.8% at five years). In an incremental multivariate analysis model, exercise echocardiography increased the chi-square of the clinical and exercise ECG model from 29 to 44.8 (p = 0.0001). CONCLUSIONS: Exercise echocardiography provides incremental data for risk stratification of diabetic patients with known or suspected IHD. Patients with a normal exercise echocardiogram have a low event rate. Patients with multivessel distribution of exercise echocardiographic abnormalities are at the highest risk of cardiac events, as one-third of these patients experience cardiac death or nonfatal MI during the five years following exercise echocardiography.     

Prognostic implications of rest and exercise radionuclide ventriculography in patients with suspected or proven coronary heart disease

Rest and exercise radionuclide ventriculography were assessed for their value in predicting major cardiac events in patients with chest pain. Of 219 patients who were followed for up to 51 months, 42 had major cardiac events: 12 patients (5.5%) died, 5 (2.2%) sustained nonfatal myocardial infarction, and 25 (11.4%) had coronary arterial bypass grafting. Univariate and multivariate survival analysis revealed that exercise left ventricular ejection fraction was the best predictor for total major events and the resting ejection fraction to be the best predictor for death or nonfatal myocardial infarction. These two variables were strong predictors in the entire group of patients and in subgroups: patients with or without Q-wave infarction, patients with high probability of coronary artery disease and those with abnormal resting left ventricular function. Thus, radionuclide angiography provides important prognostic data that permits the physician to categorize patients with chest pain syndromes with respect to subsequent cardiac events. If validated, this model or a modification of it could identify patients at high risk of subsequent major cardiac events who are candidates for intensive follow up and therapy or further invasive evaluation, as well as patients at low risk of subsequent major cardiac events for whom standard follow up would be appropriate.     

Seven-year follow-up after dobutamine stress echocardiography: impact of gender on prognosis

OBJECTIVES: The aim of this study was to investigate the effects of gender on long-term prognosis of patients undergoing dobutamine stress echocardiography (DSE). BACKGROUND: Gender differences in the predictors of outcome among patients with known or suspected coronary artery disease undergoing DSE have not been adequately studied. METHODS: We studied 2,276 men and 1,105 women with known or suspected coronary artery disease who underwent DSE. Follow-up events were cardiac death and nonfatal myocardial infarction (MI). RESULTS: Dobutamine stress echocardiography was normal in 687 men (30%) and 483 women (44%) (p <0.0001). Ischemia on DSE was present in 1,194 men (52%) and 416 women (38%) (p <0.001). During a mean follow-up of 7 +/- 3.4 years, there were 894 (26%) deaths (442 attributed to cardiac causes) and 145 (4%) nonfatal MIs. The annual cardiac event rate was 2.5% in men and 1.2% in women with normal DSE. Independent predictors of cardiac events in patients with normal DSE using a Cox proportional hazards regression analysis were male gender (hazard ratio [HR]: 1.7 [range 1.1 to 2.8]), age (HR: 1.02 [range 1.01 to 1.04]), history of heart failure (HR: 3.4 [range 1.5 to 7.9]), previous MI (HR: 1.7 [range 1.1 to 2.8]), and diabetes (HR: 2.4 [range 1.3 to 4.5]). Independent predictors of cardiac events in patients with an abnormal DSE were age (HR: 1.03 [range 1.02 to 1.04]), history of heart failure (HR: 1.7 [range 1.3 to 2.1]), diabetes (HR: 1.4 [range 1.1 to 1.8]), heart rate at rest (HR: 2.8 [range 1.4 to 5.8]), wall motion abnormalities at rest (HR: 1.06 [range 1.04 to 1.09]), and ischemia on DSE (HR: 1.04 [range 1.02 to 1.07]). Myocardial ischemia was an independent predictor of cardiac events in both men and women. CONCLUSIONS: Dobutamine stress echocardiography provides independent prognostic information in both men and women. In patients with normal DSE, gender is independently associated with cardiac events. The outcome of patients with abnormal DSE is not related to gender, after adjusting for stress echocardiographic abnormalities.     

Exercise echocardiographic findings and outcome of patients referred for evaluation of dyspnea

OBJECTIVES: The purpose of this study was to characterize the outcome of patients referred for exercise echocardiographic evaluation of dyspnea. BACKGROUND: Little information exists regarding outcome of patients with dyspnea. METHODS: We identified 443 patients with unexplained dyspnea, 2,033 with chest pain, and 587 with both symptoms referred for exercise echocardiography. RESULTS: Compared to those with chest pain alone, patients referred for dyspnea alone were older, predominantly men, and had lower workload, lower ejection fraction (EF), more prior myocardial infarction (MI), and abnormal rest electrocardiograms. Patients with both symptoms were similar to those with dyspnea, but more had prior revascularization. Exercise echocardiography showed ischemia in 42% of patients with dyspnea, 19% with chest pain, and 58% with both symptoms. During 3.1 +/- 1.8 years follow-up, cardiac death (5.2% vs. 0.9%, p < 0.0001) and nonfatal MI (4.7% vs. 2.0%, p < 0.0001) occurred more often in patients with dyspnea. Events in patients with both symptoms were similar to those with dyspnea, except for revascularization (20% vs. 13%, p = 0.0004). For patients with dyspnea, independent predictors of events were previous MI (hazard ratio [HR] 3.35, p < 0.0001), male gender (HR 1.94, p = 0.0252), EF (HR 0.95/10% increment, p < 0.0001), and increase in wall motion score index with exercise (HR 4.19/0.25 U, p < 0.0001), but not chest pain. CONCLUSIONS: Patients with unexplained dyspnea have a high likelihood of ischemia and an increased incidence of cardiac events. Exercise echocardiography provides independent information for identifying patients at risk. In patients with known or suspected coronary artery disease, dyspnea is a symptom requiring investigation.     

Prognostic significance of myocardial ischemia during dobutamine stress echocardiography in asymptomatic patients with diabetes mellitus and no prior history of coronary events

The prognostic significance of myocardial ischemia assessed by dobutamine stress echocardiography in asymptomatic patients with diabetes mellitus who have no previous coronary artery disease remains unclear. We assessed the value of dobutamine stress echocardiography for risk stratification in 161 asymptomatic patients with type 2 diabetes (mean 62 +/- 12 years of age; 96 men) who had no previous myocardial infarction or revascularization. End point during follow-up was hard cardiac events (cardiac death and nonfatal myocardial infarction). Ischemia was detected in 45 patients (28%). During a median follow-up of 5 years, 40 patients (25%) died (18 cardiac deaths) and 7 patients had nonfatal myocardial infarction (25 hard cardiac events). An abnormal dobutamine stress echocardiogram was associated with a higher mortality compared with a normal dobutamine stress echocardiogram (p = 0.03). In an incremental multivariate analysis model, clinical predictors of hard cardiac events were age and hypercholesterolemia. Ischemia was incremental to the clinical parameters. In conclusion, myocardial ischemia is an independent predictor of cardiac events in asymptomatic diabetic patients with no previous coronary artery disease.