For Low-Risk Patients With Suspected Acute Coronary Syndrome, Should Urgent (72-hours) Non-Invasive Cardiac Testing Be Performed After Biomarker Exclusion of Acute Myocardial Infarction

Prospective Validation and Comparative Analysis of Coronary Risk Stratification Strategies Among Emergency Department Patients With Chest Pain

Background

Coronary risk stratification is recommended for emergency department patients with chest pain. Many protocols are designed as “rule‐out” binary classification strategies, while others use graded‐risk stratification. The comparative performance of competing approaches at varying levels of risk tolerance has not been widely reported.

Methods and Results

This is a prospective cohort study of adult patients with chest pain presenting between January 2018 and December 2019 to 13 medical center emergency departments within an integrated healthcare delivery system. Using an electronic clinical decision support interface, we externally validated and assessed the net benefit (at varying risk thresholds) of several coronary risk scores (History, ECG, Age, Risk Factors, and Troponin [HEART] score, HEART pathway, Emergency Department Assessment of Chest Pain Score Accelerated Diagnostic Protocol), troponin‐only strategies (fourth‐generation assay), unstructured physician gestalt, and a novel risk algorithm (RISTRA‐ACS). The primary outcome was 60‐day major adverse cardiac event defined as myocardial infarction, cardiac arrest, cardiogenic shock, coronary revascularization, or all‐cause mortality. There were 13 192 patient encounters included with a 60‐day major adverse cardiac event incidence of 3.7%. RISTRA‐ACS and HEART pathway had the lowest negative likelihood ratios (0.06, 95% CI, 0.03–0.10 and 0.07, 95% CI, 0.04–0.11, respectively) and the greatest net benefit across a range of low‐risk thresholds. RISTRA‐ACS demonstrated the highest discrimination for 60‐day major adverse cardiac event (area under the receiver operating characteristic curve 0.92, 95% CI, 0.91–0.94, P<0.0001).

Conclusions

RISTRA‐ACS and HEART pathway were the optimal rule‐out approaches, while RISTRA‐ACS was the best‐performing graded‐risk approach. RISTRA‐ACS offers promise as a versatile single approach to emergency department coronary risk stratification.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03286179.

The distribution of cardiac diagnostic testing for acute coronary syndrome in the Brazilian healthcare system: A national geospatial evaluation of health access

BACKGROUND

Little is known about the utilization of cardiac diagnostic testing in Brazil and how such testing is related with local rates of acute coronary syndrome (ACS)-related mortality.

METHODS AND RESULTS

Using data from DATASUS, the public national healthcare database, absolute counts of diagnostic tests performed were calculated for each of the 5570 municipalities and mapped. Spatial error regression and geographic weighted regression models were used to describe the geographic variation in the association between ACS mortality, income, and access to diagnostic testing. From 2008 to 2014, a total of 4,653,884 cardiac diagnostic procedures were performed in Brazil, at a total cost of $271 million USD. The overall ACS mortality rate during this time period was 133.8 deaths per 100,000 inhabitants aged 20 to 79. The most commonly utilized test was the stress ECG (3,015,993), followed by catheterization (862,627), scintigraphy (669,969) and stress echocardiography (105,295). The majority of these procedures were conducted in large urban centers in more economically developed regions of the country. Increased access to testing and increased income were not uniformly associated with decreased ACS mortality, and tremendous geographic heterogeneity was observed in the relationship between these variables.

CONCLUSIONS

The majority of testing for ACS in Brazil is conducted at referral centers in developed urban settings. Stress ECG is the dominant testing modality in use. Increased access to diagnostic testing was not consistently associated with decreased ACS mortality across the country.