Long Term Favorable Prognostic Value of Negative Treadmill Echocardiogram in the Setting of Abnormal Treadmill Electrocardiogram: A 95 Month Median Duration Follow-Up Study

Abnormal Exercise Electrocardiography With Normal Stress Echocardiography Is Associated With Subclinical Coronary Atherosclerosis

BACKGROUND

Patients with abnormal (positive) exercise electrocardiography, but normal stress echocardiography (+ECG/-Echo), have an increased risk of adverse cardiovascular events compared with patients with a normal (negative) ECG and a normal stress Echo (-ECG/-Echo). However, it is unclear if +ECG/-Echo discordance is associated with a greater burden of subclinical coronary atherosclerosis.

METHODS

Project Baseline Health Study participants who underwent a stress Echo and coronary artery calcium (CAC) scan were stratified by stress Echo result: -ECG/-Echo or +ECG/-Echo. Multivariable regression investigated the association between stress Echo results and CAC burden. Event-free survival from a composite of adverse cardiovascular events was compared between groups.

RESULTS

Among 1630 asymptomatic participants in this observational cohort study, 1503 (92.2%) had a -ECG/-Echo, 105 (6.4%) had a +ECG/-Echo, and 22 (1.3%) had a +Echo. The +ECG/-Echo group had a significantly greater burden of coronary atherosclerosis than the -ECG/-Echo group (mean CAC score, 198±470 versus 53±186; P<0.001; CAClog, 2.2±2.7 versus 1.2±2.0; P<0.001). The -ECG/-Echo group was more likely to have CAC=0 compared with the +ECG/-Echo group (65.9% versus 53.3%; P=0.01), whereas the +ECG/-Echo group more commonly had CAC ≥100 (28.6% versus 11.4%; P<0.001). After adjustment, CAClog scores were 52% higher in the +ECG/-Echo group than in the -ECG/-Echo group (P=0.002). Compared with the -ECG/-Echo group, the +ECG/-Echo group was 4.5× more likely to have a CAC score ≥400 (adjusted odds ratio, 4.54 [95% CI, 1.95-10.05]; P<0.001). After a median follow-up of 4.3 years, a trend toward increased adverse cardiovascular events was observed among participants with +ECG/-Echo.

CONCLUSIONS

Individuals with a +ECG/-Echo have a higher burden of subclinical coronary atherosclerosis than those with a -ECG/-Echo, which may explain, at least in part, the increased risk for adverse cardiac events in this population. Further study is needed to determine the optimal strategy for mitigating cardiovascular risk in these patients.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03154346.

Significance of abnormal stress electrocardiography with normal cardiac imaging during stress testing-a meta-analysis

BACKGROUND AND AIMS

Diagnostic testing for coronary artery disease frequently involves functional stress testing where imaging is often coupled with electrocardiogram (ECG) analysis. While decision-making is straightforward when both functional testing and ECG are either positive or negative, interpretation is challenging and prognostic importance uncertain with positive ECG and negative imaging since imaging is considered more sensitive. Prior studies have demonstrated mixed results. We sought to perform a meta-analysis of published studies to determine the significance of this particular type of discordant stress test result.

METHODS AND RESULTS

PubMed, Cochrane, and Google Scholar were searched to identify studies reporting results of functional imaging (pharmacological exercise echocardiography or SPECT) and ECG analysis, along with the major adverse cardiovascular events (MACE) at patient follow-up. Studies were stratified based on functional imaging modality used. Primary outcome was a composite of all-cause death or myocardial infarction, and secondary outcome was the need for coronary revascularization. Random effects model was used to calculate risk ratios (RR), and heterogeneity among studies was assessed using the Higgins I2 value. Nine studies with a total of 23,715 patients were included. Primary end point was more common with discordant results with exercise stress echocardiography (RR 1.33, 95% confidence intervals [1.08-1.63]) or pharmacological SPECT (RR 6.53 95% CI [2.31-18.48]).

CONCLUSIONS

Patients in the discordant exercise stress echocardiography and pharmacological SPECT groups were more likely to suffer the primary end point than those with a normal stress test. Discordant results should be interpreted carefully in the clinical context, given their prognostic impact based on the stress modality used.

What are the prognostic implications and factors relating to exercise induced electrocardiographic ST segment changes in the setting of a non-ischemic stress echocardiogram?

BACKGROUND

Electrocardiographic (ECG) changes during stress testing are a common and perplexing finding during non-ischemic stress echocardiography (niSE). Research has provided conflicting results regarding the implications.

METHODS

SE was performed after maximal Bruce protocol treadmill exercise.

RESULTS

3020 consecutive patients, mean age 58 ± 12 years, 36% female, were followed-up for up to 9 years (mean 36 ± 21 months) post niSE. Time to first cardiac event (composite of heart failure admission, worsening New York Heart Association class, worsening ejection fraction, acute coronary syndrome, revascularization, angina or cardiovascular death) was analysed and adjusted using Cox proportional hazards regression. Prognostic significance was found with 1.5 mm of downsloping or horizontal ST depression. Adjusting for baseline differences, increased risk of composite major adverse cardiac events was shown with at least 1.5 mm of exercise induced ST depression (Hazard ratio [HR] of 2.47, 95% Confidence ratio [CI] 1.67-3.72, p < 0.0001). Patients achieving high level exercise capacity (≥13 metabolic equivalents or METs) with ST depression lower risk of cardiac events during follow-up.

CONCLUSION

Patients with ST segment depression but non-ischemic stress imaging have a poorer prognosis compared to patients with niSE with normal stress ECGs. ST depression of 1.5 mm or more was established as a prognostically significance value. High exercise capacity was associated with an improved prognosis, and ECG changes in that setting can be regarded as false positives. All niSE have low risk of a cardiac event in the very short term (<12 months). Overall, ST depression during non-ischaemic stress imaging is not a benign finding.

Stress Electrocardiography Testing in Coronary Artery Disease: Is It Time for Its Swan Song or To Redefine Its Role in the Modern Era ?

Stress electrocardiography (sECG) or treadmill stress testing is a well validated noninvasive diagnostic modality available to clinicians at low cost yet providing valuable functional data for coronary artery disease (CAD) diagnostic and prognostic evaluation. With the advances in cardiac imaging in both functional and anatomic fronts and the existing limitations of sECG testing, this modality appears less favored worldwide as reflected in some recent guideline updates. We review the past present and future of sECG to provide a viewpoint on where it stands in CAD evaluation and if it will remain relevant as a diagnostic modality or be retired going forward. We also provide our perspectives on how sECG can co-exist with other modalities such as calcium scoring and discuss the role of such testing in the Indian population.

Implications of Abnormal Exercise Electrocardiography With Normal Stress Echocardiography

IMPORTANCE

Patients with abnormal (positive) exercise electrocardiography, but normal stress echocardiography (+ECG/-Echo) are commonly encountered in clinical practice; however, the prognostic significance of this discordant result is unclear.

OBJECTIVE

To determine whether patients with +ECG/-Echo have a higher rate of adverse clinical events and a poorer prognosis than patients with negative exercise ECG and normal stress Echo imaging (-ECG/-Echo).

DESIGN, SETTING, AND PARTICIPANTS

Between January 1, 2000, and February 28, 2014, a total of 47 944 consecutive patients without known coronary artery disease who underwent exercise stress Echo at Duke University Medical Center were evaluated for inclusion in this observational cohort study. Data analysis was conducted from January 1, 2000, to December 31, 2016.

INTERVENTIONS/EXPOSURES

Patients were categorized as having -ECG/-Echo, +ECG/-Echo, or +Echo (-ECG/+Echo and +ECG/+Echo).

MAIN OUTCOMES AND MEASURES

The primary outcome was a composite end point of death, myocardial infarction, hospitalization for unstable angina, and coronary revascularization. Secondary outcomes included individual adverse events and downstream testing.

RESULTS

After excluding submaximal tests and nondiagnostic ECG or stress imaging results, 15 077 patients (mean [SD] age, 52 [13] years; 6228 [41.3%] men) were classified by stress test results. Of these, 12 893 patients (85.5%) had -ECG/-Echo, 1286 patients (8.5%) had +ECG/-Echo, and 898 patients (6.0%) had +Echo. Through a median follow-up of 7.3 (interquartile range, 4.4-10.0) years, the composite end point occurred in 794 patients with -ECG/-Echo (8.5%), 142 patients with +ECG/-Echo (14.6%), and 297 patients with +Echo (37.4%). Death occurred in 425 patients with -ECG/-Echo (4.8%), 50 patients with +ECG/-Echo (5.9%), and 70 patients with +Echo (11.2%). Myocardial infarction occurred in 195 patients with -ECG/-Echo (2.2%), 31 patients with +ECG/-Echo (3.6%), and 59 patients with +Echo (8.7%). The addition of stress ECG findings to clinical and exercise data yielded incremental prognostic value. Patients with -ECG/-Echo imaging results had the least downstream testing (2.3%), followed by +ECG/-Echo (12.8%), and +Echo (33.6%) (P < .001).

CONCLUSIONS AND RELEVANCE

The presence of +ECG results with normal stress Echo imaging may identify a population of patients who are at slightly increased risk for adverse cardiac events, which was not previously recognized. Further study is needed to determine whether these patients will benefit from intensification of medical management.

Usefulness of Excellent Functional Capacity in Men and Women With Ischemic Exercise Electrocardiography to Predict a Negative Stress Imaging Test and Very Low Late Mortality

Exercise electrocardiography (ExECG) is widely employed to assess patients for coronary artery disease but it has limited diagnostic accuracy. Many patients with positive (ischemic) tests based on exercise-induced ST depression undergo secondary evaluation by noninvasive stress imaging. We hypothesized that high functional capacity in patients with positive ExECG could predict: (1) negative results in secondary evaluation by exercise echocardiography (ESE) or myocardial perfusion scintigraphy (MPS) and (2) low mortality on late follow-up. We evaluated 511 consecutive patients (312 men, 199 women; age 51 ± 9 years) referred for ESE or MPS after an ischemic ExECG at a treadmill workload of ≥10 metabolic equivalents. All-cause mortality was also obtained. Of 511 patients, 401 underwent ESE and 110 had MPS for secondary study. ESE was negative in 94% (376 of 401) and positive in 6% (25 of 401). MPS was also negative in 94% (103 of 110) and positive in 6% (7 of 110). Total stress imaging results were negative in 92% (286 of 312) of men and 97% (193 of 199) of women. During follow-up of approximately 6 years, there were 3 deaths with total all-cause mortality of 0.6% and average annual mortality of 0.1%. In conclusion, high functional capacity in patients with an ischemic ExECG predicts a negative ESE or MPS in a large majority of patients and very favorable late survival in both men and women. These results suggest that patients with ischemic ExECGs and a workload of ≥10 metabolic equivalents during ExECG may not require additional noninvasive or invasive evaluation.

Clinical outcomes of discordant exercise electrocardiographic and echocardiographic findings compared with concordant findings in patients with chest pain and no history of coronary artery disease: An observational study

The aim of this study was to evaluate comparative clinical outcomes of discordant electrocardiographic (ECG) and echocardiographic (Echo) findings compared with concordant findings during treadmill exercise echocardiography in patients with chest pain and no history of coronary artery disease (CAD).A total of 1725 consecutive patients who underwent treadmill echocardiography with chest pain and no history of CAD were screened. The patients were classified into 4 groups: ECG-/Echo- (negative ECG and Echo), ECG+/Echo- (positive ECG and negative Echo), ECG-/Echo+, and ECG+/Echo+. Concomitant CAD was determined using coronary angiography or coronary computed tomography. Major adverse cardiac events (MACEs) were defined as a composite of coronary revascularization, acute myocardial infarction, and death.MACEs were similar between ECG-/Echo- and ECG+/Echo- groups. Compared with ECG+/Echo- group, ECG-/Echo+ group had more MACEs (adjusted hazard ratio [HR] adjusted by clinical risk factors [95% confidence interval {CI}], 3.57 [1.75-7.29], P < .001). Compared with ECG+/Echo+ group, ECG-/Echo+ group had lower prevalence of concomitant CAD and fewer MACEs (HR, 0.49 [0.29-0.81], P = .006).Positive exercise Echo alone during treadmill exercise echocardiography had worse clinical outcomes than positive ECG alone, and the latter had similar outcomes to both negative ECG and Echo. Positive exercise Echo alone also had better clinical outcomes than both positive ECG and Echo. Therefore, exercise Echo findings might be superior for predicting clinical outcomes compared with exercise ECG findings. Additional consideration of ECG findings on positive exercise Echo will also facilitate better prediction of clinical outcomes.

The value of negative stress echocardiography in predicting cardiovascular events among adults with no known coronary disease

Introduction: Stress echocardiography is a safe and cost-effective method of evaluating the patients with suspected coronary artery disease (CAD). However, the risk factors of an adverse cardiovascular event after a normal exercise (ESE) or dobutamine (DSE) stress echocardiography are not well established.

Methods: A cohort of 705 patients without previous history of CAD and a negative ESE/DSE was studied. All studies were performed in a high-volume echocardiologic laboratory and interpreted by two experienced echocardiography-trained cardiologists. Patients with inconclusive studies and those with an evidence of myocardial ischemia were excluded. Demographic, echocardiographic and hemodynamic findings were recorded. Patients were followed for at least 2 years. Independent predictors of major adverse cardiovascular events (MACE) were determined by regression analysis.

Results: During a period of 55.7±17.5 months, MACE occurred in 35 (5.0%) of patients. Negative predictive value (NPV) of DSE was 89.2%, which was significantly less than 96.5% for ESE in predicting the occurrence of MACE (P = 0.001). MACE occurred more frequently among older (≥65 years) men with preexisting diabetes, hypertension, and/or hyperlipidemia. During ESE, a higher maximum blood pressure*heart rate product for the achieved level of metabolic equivalent (METS) of tasks was also an independent predictor of MACE.

Conclusion: Inability of patients to undergo traditional ESE that led to the choice of using DSE alternative reduces the NPV of the stress echocardiography among patients without previous history of CAD. A modest rise of heart rate and blood pressure in response to increased level of activity serves as favorable prognostic value and improves the NPV of stress echocardiography.

Cardiorespiratory Fitness and Cardiovascular Disease Prevention: an Update

PURPOSE OF REVIEW

Cardiovascular diseases account for nearly one third of all deaths globally. Improving exercise capacity and cardiorespiratory fitness (CRF) has been an important target to reduce cardiovascular events. In addition, the American Heart Association defined decreased physical activity as the fourth risk factor for coronary artery disease. Multiple large cohort studies have evaluated the impact of CRF on outcomes. In this review, we will discuss the role of CRF in reducing cardiovascular morbidity and mortality.

RECENT FINDINGS

Recent data suggest that CRF has an important role in reducing not only cardiovascular and all-cause mortality, but also incident myocardial infarction, hypertension, diabetes, atrial fibrillation, heart failure, and stroke. Most recently, its role in cancer prevention started to emerge. CRF protective effects have also been seen in patients with prior comorbidities like prior coronary artery disease, heart failure, depression, end-stage renal disease, and stroke. The prognostic value of CRF has been demonstrated in various patient populations and cardiovascular conditions. Higher CRF is associated with improved survival and decreased incidence of cardiovascular diseases (CVD) and other comorbidities including hypertension, diabetes, heart failure, and atrial fibrillation.

Prognostic value of a negative peak supine bicycle stress echocardiography with or without concomitant ischaemic stress electrocardiographic changes: a cohort study

BACKGROUND

a negative peak supine bicycle exercise stress echocardiography (ESE) was shown to have a long-term favourable prognostic value. Data on the long-term prognosis of ischaemic electrocardiographic (ISECG) changes in the setting of a negative peak supine bicycle ESE are lacking.

DESIGN

we evaluated the prognostic value of negative peak supine bicycle ESE with or without concomitant ISECG changes in a referral population evaluated for chest pain after an inconclusive first-line work-up including clinical evaluation and exercise ECG stress.

METHODS

from 2003 to 2010, patients who underwent a peak supine bicycle ESE and were deemed to be negative were evaluated. Two groups based on concomitant stress ECG tracing were analysed - those with normal stress ECG and those with ISECG changes. The primary endpoint was cumulative incidence of cardiovascular death, hospitalizations for acute coronary syndrome and coronary revascularizations.

RESULTS

a total of 371 patients (mean age 59.1 ± 12.1 years, 49.9% women) were studied. Of those, 141 (38.0%) had concomitant ISECG changes. Mean follow-up was 3.46 ± 1.76 years. The primary endpoint occurred in 3.0% of patients, (2.2% in those with normal stress ECG, and in 4.3% with ISECG changes, p = 0.251); with unadjusted hazard ratio for primary endpoint of 2.04 (95%CI 0.62-6.69, p = 0.239) in patients with ISECG changes compared to those with normal stress ECG.

CONCLUSIONS

in an outpatient population without known CAD evaluated for chest pain after inconclusive first-line work-up, a negative peak supine bicycle ESE confers an excellent prognosis regardless of the nature of concomitant stress ECG abnormalities.