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Robert B McCully

Publications and source records attributed to Robert B McCully.

17 recordsLinked to original sources

Outcomes after normal dobutamine stress echocardiography and predictors of adverse events: long-term follow-up of 3014 patients.

AIMS: Normal exercise echocardiography predicts a good prognosis. Dobutamine stress echocardiography (DSE) is generally reserved for patients with comorbidities which preclude exercise testing. We evaluated predictors of adverse events after normal DSE. METHODS AND RESULTS: We studied 3014 patients (1200 males, 68+/-12 years) with normal DSE, defined as the absence of wall motion abnormality at rest or with stress. During median follow-up of 6.3 years, all-cause mortality and cardiac events, defined as myocardial infarction and coronary revascularization, occurred in 920 (31%) and 231 (7.7%) patients, respectively. Survival and cardiac event-free probabilities were 95 and 98% at 1 year, 78 and 93% at 5 years, and 56 and 89% at 10 years, respectively. Age, diabetes mellitus, and failure to achieve 85% age-predicted maximal heart rate were independent predictors of mortality and cardiac events. Patients with all three of these characteristics had a 13% probability of cardiac events within the first year and higher risk throughout follow-up. CONCLUSION: Prognosis after normal DSE is not necessarily benign, but depends on patient and stress test characteristics. Careful evaluation, using clinical and stress data, is required to identify patients with normal DSE who are at increased risk of adverse outcomes during long-term follow-up.

Aged↗

Relationship between coronary artery calcification detected by electron-beam computed tomography and abnormal stress echocardiography: association and prognostic implications.

OBJECTIVES: The purpose of this study was to compare the results and prognostic value of electron-beam computed tomography (EBCT) and exercise echocardiography. BACKGROUND: Although patients with elevated coronary artery calcium scores (CACS) might be referred for exercise echocardiography, the association of EBCT CACS with wall motion score index (WMSI) is not known. METHODS: Patients without known coronary artery disease who underwent both clinically indicated EBCT and exercise echocardiography within a 3-month period were identified. Exercise WMSI was based on a 16-segment model (normal = 1; abnormal >1). The EBCT CACS was derived with the Agatston scoring system. Follow-up was obtained for the combined end point of death and myocardial infarction. RESULTS: The study population included 556 patients (age 54 +/- 10 years; 65% male). Correlation between EBCT CACS and exercise WMSI was limited (r = 0.17, p < 0.0001) but statistically significant. The proportion of patients with abnormal exercise WMSI increased with increasing CACS severity (chi-square = 19.1, p < 0.001). However, even in those with CACS >400, 66% had normal exercise WMSI. Age, CACS, and chest pain were independently associated with abnormal exercise WMSI. Events occurred in 12 (2%) patients. Wall motion score index (risk ratio [RR] 3.7, p = 0.023) and age (RR 1.9, p = 0.019) were associated with events. CONCLUSIONS: Electron-beam computed tomography CACS was predictive of abnormal exercise WMSI, but the majority of patients with elevated CACS had normal WMSI. Wall motion score index and age were the best predictors of events. Prospective studies are indicated to establish the relative roles of these tests in risk stratification.

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Predictive value of normal left atrial volume in stress echocardiography.

OBJECTIVES: Our objective was to evaluate whether normal left atrial volume index (LAVI) is a predictor of a normal stress echocardiogram and thus a predictor of low ischemic risk. BACKGROUND: Left atrial enlargement is closely related to the chronicity and intensity of the burden of increased ventricular filling pressure. Typically ischemic heart disease (IHD) has a long period of subclinical dysfunction. Increased filling pressure, reflected by enlarged LAVI, is hypothesized to mirror the burden of subclinical and overt IHD. We hypothesized that a normal LAVI might also be useful in predicting low IHD risk. METHODS: One hundred eighty randomly selected patients (mean age, 63 +/- 15 years; 53% men) underwent outpatient exercise or dobutamine stress echocardiography for known or suspected coronary artery disease. Left atrial volume index was measured retrospectively with the biplane area-length method. The stress echocardiogram was interpreted as abnormal if wall motion abnormalities (WMAs) were noted at rest and/or with stress. RESULTS: Left atrial volume index was categorized as < or =28 ml/m2 (normal), 28.1 to 32 ml/m2, 32.1 to 36 ml/m2, and >36 ml/m2. Abnormal stress echocardiography was identified in 57 patients (31.7%). The percentage of abnormal stress echocardiograms in each LAVI category was 5.7%, 21.9%, 38.7%, and 54.7%, respectively. The negative predictive value for LAVI < or =28 ml/m2 was 94.3%. CONCLUSIONS: Normal resting LAVI (< or =28 ml/m2) was strongly predictive of a normal stress echocardiogram. Left atrial volume index might be a simple means of identifying patients with low ischemic risk and should be further evaluated as a complement to the assessment of ischemic risk.

Adult↗

Dobutamine stress echocardiography in patients with diabetes mellitus: enhanced prognostic prediction using a simple risk score.

OBJECTIVES: We sought to determine the prognostic value of dobutamine stress echocardiography (DSE) for predicting long-term outcomes in a large cohort with diabetes mellitus and to develop a simple risk score using clinical and echocardiographic data. BACKGROUND: Neither risk scores nor long-term prognostic value of DSE has been described in a large diabetic population. METHODS: We studied 2,349 patients with diabetes mellitus (1,338 men, 67 +/- 11 years of age) during a follow-up of 5.4 +/- 2.2 years. RESULTS: Mortality and morbidity (myocardial infarction and late coronary revascularization) occurred in 1,044 (44%) and 309 (13%) patients, respectively. Addition of stress echocardiographic variables to the clinical and rest echocardiographic model provided incremental prognostic information for predicting mortality (chi-square = 243 to 270, p < 0.0001) and morbidity (chi-square = 38 to 78, p < 0.0001). For each end point, a simple risk score was derived according to the estimated values of beta coefficients of multivariate predictors (insulin therapy, smoking, failure to achieve target heart rate, percentage of ischemic segments, and impaired left ventricular systolic function) and resulted in an assessment of risk among all age groups. The C-statistic values were 0.60 to 0.64, indicating modest discrimination. The estimated five-year event-free survivals of patients in three risk categories were 94%, 86%, and 80% for morbidity (p < 0.00001) and 69%, 60%, and 47% for mortality (p < 0.0001). CONCLUSIONS: In patients with diabetes mellitus, a simple and practical risk score using clinical variables and results of DSE stratified patients into three risk groups for mortality and cardiovascular morbidity.

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Role of biplane and biplane echocardiographically guided 3-dimensional echocardiography during dobutamine stress echocardiography.

Image acquisition time and wall-motion score of conventional 2-dimensional (2D) dobutamine stress echocardiography (DSE) were compared with those of biplane and 3-dimensional (3D) DSE in 50 patients (age 67 +/- 13 years) with regular rhythms during clinically indicated DSE. Commercially available systems were used for the study. We used a conventional transducer for 2D and a matrix-array transducer (x4 or x3-1) for two biplane (60- and 120-degree) images and one 3D full-volume image. Image quality was scored as 1 = good; 2 = adequate; and 3 = inadequate. Segmental wall-motion scores for each method were analyzed in blinded fashion. Acquisition times of biplane (9.3 +/- 2.8 seconds) and biplane-guided 3D (additional 2.6 +/- 1.0 seconds) echocardiography were significantly shorter than those of conventional 2D DSE (60.0 +/- 26.7 seconds) (P < .001). Image quality was adequate or good in 94% for biplane and 96% for 3D echocardiography. Agreement of segmental wall-motion score was present in 87.6% of segments for 2D versus biplane and 85.9% for 2D versus 3D at baseline and in 88.0% for 2D versus biplane and 87.4% for 2D versus 3D at peak stress. Acquisition of biplane or biplane-guided 3D volumetric data during DSE with use of a new matrix-array transducer was feasible and shortened image acquisition time without affecting the diagnostic yield compared with conventional 2D imaging.

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Effects of pulmonary thromboendarterectomy on right-sided echocardiographic parameters in patients with chronic thromboembolic pulmonary hypertension.

OBJECTIVE: To determine the echocardiographic changes in the heart at 3 months and 1 year after pulmonary thromboendarterectomy (PTE) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). PATIENTS AND METHODS: Thirty-two adult patients who underwent PTE for CTEPH at the Mayo Clinic in Rochester, Minn, from 1997 to 2003 were included in the study. All underwent transthoracic echocardiography before surgery. Follow-up echocardiography was performed within 3 months of surgery in 28 patients and 1 year postoperatively in 17 patients. The results were compared with baseline data. RESULTS: Within 3 months after PTE, the right ventricular end-diastolic area decreased from 38.4 +/- 12.8 cm2 to 32.5 +/- 10.4 cm2 (mean difference, 5.8 +/- 10.4 cm2; P = .02). The right ventricular end-systolic area decreased from 30.4 +/- 12.1 cm2 to 24.1 +/- 8.6 cm2 (mean difference, 6.3 +/- 10.1 cm2; P = .008). The right ventricular systolic pressure decreased significantly from 92.6 +/- 22.0 mm Hg to 55.0 +/- 19.8 mm Hg (mean difference, 40.0 +/- 24.8 mm Hg; P < .001). Tricuspid regurgitation (TR) improved from a mean grade of 2.5 +/- 1.2 to 1.2 +/- 1.1 (mean difference, 1.5 +/- 1.0; P < .001). At 12 months, the right ventricular end-diastolic area, right ventricular end-systolic area, right ventricular systolic pressure, and TR also were significantly lower than baseline values. CONCLUSION: In patients with CTEPH who undergo PTE, echocardiographic measurements of right ventricular size, systolic pressure, and TR show significant improvement immediately after surgery, which is sustained for up to 1 year after surgery.

Adult↗

Long-term effects of surgical septal myectomy on survival in patients with obstructive hypertrophic cardiomyopathy.

OBJECTIVES: This study sought to determine the impact of surgical myectomy on long-term survival in hypertrophic cardiomyopathy (HCM). BACKGROUND: Left ventricular (LV) outflow tract obstruction in HCM increases the likelihood of heart failure and cardiovascular death. Although surgical myectomy is the primary treatment for amelioration of outflow obstruction and advanced drug-refractory heart failure symptoms, its impact on long-term survival remains unresolved. METHODS: Total and HCM-related mortality were compared in three subgroups comprised of 1,337 consecutive HCM patients evaluated from 1983 to 2001: 1) surgical myectomy (n = 289); 2) LV outflow obstruction without operation (n = 228); and 3) nonobstructive (n = 820). Mean follow-up duration was 6 +/- 6 years. RESULTS: Including two operative deaths (procedural mortality, 0.8%), 1-, 5-, and 10-year overall survival after myectomy was 98%, 96%, and 83%, respectively, and did not differ from that of the general U.S. population matched for age and gender (p = 0.2) nor from patients with nonobstructive HCM (p = 0.8). Compared to nonoperated obstructive HCM patients, myectomy patients experienced superior survival free from all-cause mortality (98%, 96%, and 83% vs. 90%, 79%, and 61%, respectively; p < 0.001), HCM-related mortality (99%, 98%, and 95% vs. 94%, 89%, and 73%, respectively; p < 0.001), and sudden cardiac death (100%, 99%, and 99% vs. 97%, 93%, and 89%, respectively; p = 0.003). Multivariate analysis showed myectomy to have a strong, independent association with survival (hazard ratio 0.43; p < 0.001). CONCLUSIONS: Surgical myectomy performed to relieve outflow obstruction and severe symptoms in HCM was associated with long-term survival equivalent to that of the general population, and superior to obstructive HCM without operation. In this retrospective study, septal myectomy seems to reduce mortality risk in severely symptomatic patients with obstructive HCM.

Adult↗

Prognosis of patients with good exercise capacity and mildly abnormal exercise echocardiography results: identification of an at-risk subgroup.

BACKGROUND: Patients with good exercise capacity and mildly abnormal exercise echocardiography results have a favorable overall prognosis. OBJECTIVE: We sought to define subgroups that might be at higher risk. METHODS: We examined outcomes of 868 patients (women, > or = 5 metabolic equivalents; men, > or = 7 metabolic equivalents) with mild rest- or exercise-induced wall-motion abnormalities and evaluated potential predictors of time to cardiac death or nonfatal myocardial infarction (MI). RESULTS: Mean age was 64 +/- 10 years; 477 patients (55%) were men. Mean follow-up was 3.1 +/- 1.5 years; cardiac event rate was 1.2% per person-year. A history of MI was the only significant predictor (risk ratio, 3.9; 95% confidence interval, 1.9-7.8; P = .0001), with 1-, 3-, and 5-year event-free survival of 98.5% +/- 1.1%, 92.6% +/- 2.6%, and 83.3% +/- 5.1%, respectively (event rate, 3.4%). CONCLUSIONS: Patients with a history of MI have a higher annual cardiac event rate and may benefit from reevaluation, whereas no history of MI connotes a favorable prognosis.

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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.

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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.

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Use of a scoring model combining clinical, exercise test, and echocardiographic data to predict mortality in patients with known or suspected coronary artery disease.

The aim of this study was to derive and validate a model for predicting mortality by combining clinical, exercise testing, and echocardiographic data in patients with known or suspected coronary artery disease. We studied 5,679 patients (aged 62 +/- 12 years; 3,231 men) who were followed for a mean of 3 years after treadmill exercise echocardiography. Patients were randomly divided into 2 groups of equal size. (1) The modeling group underwent multivariate analysis to define independent predictors of mortality. Three hundred bootstrap resamplings were performed to determine parameter coefficients. Patients were divided into 5 risk categories according to their composite score and survival rate in each category was estimated by the Kaplan-Meier method. (2) The validation group comprised patients for whom the risk model was applied. Patients were divided into 5 risk categories based on data obtained from the modeling group. During follow-up, 315 patients died (151 in the modeling group). Independent predictors of mortality were exercise wall motion score index (chi-square 22.4, p <0.0001), workload (chi-square 17.1, p <0.0001), male gender (chi-square 15.4, p <0.0001), and age (chi-square 5.5, RR 1.02, 95% confidence interval 1 to 1.04; p = 0.02). Application of the composite score in the validation group resulted in an effective stratification of patients for mortality and cardiac events. This study provides a model for assessing risk of death by combining clinical, exercise testing, and echocardiographic data using a single composite score.

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Akinesia becoming dyskinesia after exercise testing: prevalence and relationship to clinical outcome.

OBJECTIVES: The aim of this study was to determine the prevalence and prognostic implications of dyskinesia developing after exercise. BACKGROUND: The prevalence and prognostic implications of new-onset dyskinesia with exercise testing have not been previously described. METHODS: We considered 1005 consecutive patients who underwent exercise echocardiography and had akinetic segments at rest. Patients were divided according to the presence or absence of exercise-induced dyskinesia. Baseline clinical and echocardiographic parameters were compared, and patients were followed up for a median of 2.7 years. RESULTS: One hundred four (10%) patients developed dyskinesia after exercise. Compared to patients with segments that remained akinetic, these patients were more likely to have electrocardiographic (ECG) evidence of prior myocardial infarction and, during exercise, had a less pronounced rise in systolic blood pressure and more often had ECG evidence of ischemia. Their resting left ventricular (LV) ejection fraction was worse and improved little after exercise. However, all-cause mortality and the incidence of major adverse cardiac events were similar in the two groups, even after correction for age, gender, and resting LV function (hazard ratio for major adverse cardiac events = 1.36, 95% confidence interval [CI] 0.82 to 2.26, p = 0.23; hazard ratio for total mortality = 1.20, 95% CI 0.75 to 1.94, p = 0.45). CONCLUSIONS: One in 10 patients with akinetic myocardium at rest will develop dyskinesia after exercise. This is associated with poorer LV function at rest and little improvement in systolic function after exercise. However, this response has no impact on prognosis.

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Outcomes of patients with reduced exercise capacity at time of exercise echocardiography.

OBJECTIVE: To characterize the prognostic implications of exercise echocardiography in patients who have reduced exercise capacity at the time of testing. PATIENTS AND METHODS: We examined the outcomes of 941 patients at the Mayo Clinic in Rochester, Minn, between January 1, 1990, and December 31, 1995, who had reduced exercise capacity on exercise echocardiography (women, <5 metabolic equivalents; men, <7 metabolic equivalents) and evaluated the potential association between clinical, electrocardiographic, and echocardiographic variables and outcomes for patients with normal vs abnormal exercise echocardiograms. We used variables of independent prognostic value to estimate cardiac risk. RESULTS: For patients with normal exercise echocardiograms (n=282), the rate of cardiac death or nonfatal myocardial infarction was 09% per person-year of follow-up, and previous coronary revascularization was the only predictor of the time to cardiac event. For patients with abnormal exercise echocardiograms (n=659), the cardiac event rate was 4.4%. Independent predictors of outcome were exercise left ventricular (LV) ejection fraction (risk ratio, 1.44 per 10% decrement; 95% confidence interval, 1.2-1.7; P<.001) and an increase or no change in LV end-systolic size in response to exercise (risk ratio, 2.22; 95% confidence interval, 1.2-4.1; P=.01). CONCLUSION: Exercise echocardiographic findings have important prognostic implications for patients who have reduced exercise capacity on testing. Echocardiographic descriptors of LV systolic function and dysfunction obtained immediately after exercise can be used to stratify cardiac risk of patients who do not achieve a level of exercise ordinarily considered to be of "diagnostic" value.

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Outcome after abnormal exercise echocardiography for patients with good exercise capacity: prognostic importance of the extent and severity of exercise-related left ventricular dysfunction.

OBJECTIVES: We sought to define the prognostic implications of the extent and severity of exercise echocardiographic abnormalities in patients with good exercise capacity. BACKGROUND; The exercise capacity of patients with known or suspected coronary artery disease (CAD) is of prognostic importance, as is the extent of exercise-related left ventricular (LV) hypoperfusion or dysfunction. METHODS: We examined the outcomes of 1,874 patients with known or suspected CAD (mean age 64 +/- 10 years, 64% men) who had good exercise capacity (> or = 5 metabolic equivalents [METs] for women, > or = 7 METs for men) but abnormal exercise echocardiograms and analyzed the potential association between clinical, exercise and echocardiographic variables and subsequent cardiac events. RESULTS: Multivariate predictors of time to cardiac death or nonfatal myocardial infarction (MI) were diabetes mellitus (risk ratio [RR] 1.88; 95% confidence interval [CI] 1.2 to 3.0), history of MI (RR 2.44; 95% CI 1.6 to 3.6) and an increase or no change in LV end-systolic size in response to exercise (RR 1.61; 95% CI 1.1 to 2.5). Using echocardiographic variables that were of incremental prognostic value, we were able to stratify the cardiac risk of the study population; cardiac death or nonfatal MI rate per person-year of follow-up was 1.6% for patients who had a decrease in LV end-systolic size in response to exercise (n = 1,330) and 1.2% for patients who did not have any severely abnormal LV segments immediately after exercise (n = 868). CONCLUSIONS: In patients with good exercise capacity, echocardiographic descriptors of the extent and severity of exercise-related LV dysfunction were of independent and incremental prognostic value. Stratification of patients into low- and higher risk subgroups was possible using these exercise echocardiographic characteristics.

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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.

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