Stress echocardiography in the ED: diagnostic performance in high-risk subgroups

Major adverse cardiac events after emergency department evaluation of chest pain patients with advanced testing: Systematic review and meta-analysis

OBJECTIVES

Our primary objective was to describe the risk of major adverse cardiac events (MACE) at 1, 6, and 12 months after a negative coronary computed tomography angiogram (cCTA), electrocardiogram (ECG) stress test, stress echocardiography, and myocardial perfusion scintigraphy (MPS) in low- to intermediate-risk patients.

METHODS

Initially, 952 articles were identified for screening, 81 met criteria for full-text review, and once risk of bias was assessed, 33 articles were included in this meta-analysis. We utilized a random-effects model to assess pooled MACE event proportion for patients undergoing evaluation of acute coronary syndrome (ACS) when risk stratified to a low- to intermediate-risk category after undergoing standard testing. Heterogeneity analysis was performed using Cochrane's Q-test and I² statistic.

RESULTS

Twenty-one studies evaluated follow-up at 1 month with cCTA having a 0.09% (95% confidence interval [CI] = 0.03% to 0.26%) pooled MACE compared to 0.23% (95% CI = 0.01% to 5.8%) of the exercise stress testing (p = 1). MPS and cCTA had an overall event rate of 0.15% (95% CI = 0.06% to 0.41%) at 6 months (I²  = 0%). At 12 months, a subgroup analysis found a pooled cCTA MACE of 0.16% (95% CI = 0.04% to 0.65%) compared to 1.68% (95% CI = 0.01% to 2.6%) for stress echocardiography with low within-group heterogeneity (I²  = 0%). Subgroup analysis of cCTA with no disease versus nonobstructive disease (<50% stenosis) did not find statistical difference in the MACE at both 1 month (0.17% [95% CI = 0.04% to 0.67%] vs. 0.06% [95% CI = 0.01% to 0.34%]) and 12 months (0.44% [95% CI = 0.09% to 2.2% vs. 0.54% [95% CI = 0.19% to 1.5%]).

CONCLUSIONS

Patients presenting with chest pain who have a coronary CTA showing < 50% stenosis, negative ECG stress test, stress echocardiography, or stress myocardial perfusion scan in the past 12 months can be discharged without any further risk stratification if their ECG and troponin are reassuring given low MACE.

Does an imaging stress-test adds information to prognostic scores in patients with chest pain in the emergency department?

We evaluated the ability of a stress-test (Str-T) to improve the risk stratification based on prognostic scores in patients presenting to the ED with chest pain. Between 2008, June and 2013, December, 1082 patients with chest pain were evaluated with an imaging Str-T. With a retrospective analysis, patients were stratified according to: (1) Florence Prediction Rule as low (0-1, LR-FPR), intermediate (2-4, IR-FPR), high risk (5-6, HR-FPR), respectively, 26, 50 and 24% of patients; (2) HEART score as LR-HEART, (0-3) and HR-HEART (≥4), respectively, 36 and 64%; (3) likelihood of CAD according to NICE guidelines, 10-29% LR-NICE, 30-60% IR-NICE and > 60% HR-NICE, respectively, 12, 18 and 70%. Scores' diagnostic performance was calculated with Str-T as reference. One-month follow-up by a phone call was performed, to investigate the occurrence of new cardiovascular events. In LR and HR patients, FPR and NICE score showed sensitivity 66 vs 93%, specificity 59 vs 19% (both p < 0.001), Positive Predictive Value (PPV) 36 vs 31%, Negative Predictive Value (NPV) 83 vs 87%. Among LR-HEART patients, Str-T was positive for inducible ischemia in 53 (14%) patients and 12 (4%) of them underwent a percutaneous coronary revascularization. The Str-T was negative for inducible ischemia in 760 (70%) patients, positive in 272 (25%), inconclusive in 50 (5%); among patients in the LR and IR subgroups, incidence of CAD (1.3 and 1.6%) and the cumulative incidence of significant events at 1-month follow-up (both 1%) was very low Str-T improved prognostic scores' diagnostic performance in LR- and HR-subgroups.

The incremental value of stress testing in patients with acute chest pain beyond serial cardiac troponin testing

OBJECTIVE

In patients with acute chest pain and normal range cardiac troponin (cTn), accurate risk stratification for acute coronary syndrome is challenging. This study assesses the incremental value of stress testing to identify patients for angiography with a view to revascularisation.

METHODS

A single-centre observational study recruited patients with acute chest pain in whom serial cTn tests were negative and stress testing (exercise tolerance testing/dobutamine stress echocardiography) was performed. Stress tests were reported as negative, non-diagnostic or positive. The primary outcomes were revascularisation on index admission, or cardiac death and myocardial infarction over 1 year follow-up.

RESULTS

Of 749 patients recruited, 709 underwent exercise tolerance testing and 40 dobutamine stress echo of which 548 (73.2%) were negative, 169 (22.6%) were non-diagnostic and 32 (4.3%) were positive. Patients with positive tests (n=19 (59.4%)) were more likely to undergo index admission revascularisation than patients with non-diagnostic (n=15 (8.9%)) (p<0.001) tests who in turn were more likely undergo index admission revascularisation than those with negative tests (n=2 (0.4%)) (p<0.001). The risks of adverse events including cardiovascular death/acute myocardial infarction were low and were similar across stress test outcomes.

CONCLUSIONS

The incremental value of stress testing was the identification of an additional 34 (4.5% (95% CI 3.0% to 6.0%)) patients who underwent index admission revascularisation with a view to preventing future adverse events. Uncertainty in whether revascularisation prevents adverse events in patients with negative cTn means the choice to undertake stress testing depends on whether clinicians perceive value in identifying 4.5% of these patients for revascularisation.

CLINICAL TRIAL REGISTRATIONS

ACTRN1260900028327, ACTRN12611001069943.