Performance of a Population-based Cardiac Risk Stratification Tool in Asian Patients with Chest Pain

Abstract

Objectives: Most contemporary cardiac risk stratification tools have been derived and validated in mixed-race populations. Their validity in single-race populations has not been tested. The authors sought to compare the performance of a risk stratification tool between a mixedrace U.S. patient population and an Asian patient population. Methods: This study is an analysis of data from the Internet Tracking Registry for Acute Coronary Syndromes (i*trACS) registry of patients with chest pain presenting to the emergency departments of eight U.S. centers and one site in Singapore. The Acute Cardiac Ischemia TimeInsensitive Predictive Instrument (ACI-TIPI) was computed for included patients, and its performance in predicting acute coronary syndrome (ACS) was compared between patients from the United States and Singapore. [Singapore]; p = 0.5611), sensitivity and specificity were different when equal ACI-TIPI thresholds were considered. Recreating the logistic regression models used to create the ACI-TIPI showed similar results between the derived parameters and the parameters estimated for the U.S. group. In contrast, age older than 50 years (log-odds ratio [LOR], 0.107; 95% confidence interval [CI] = 0.518 to 0.713), male gender (LOR, 0.487; 95% CI = 0.149 to 1.122), and chest pain as a primary complaint (LOR, 0.237; 95% CI = 0.139 to 0.613) had little predictive power in patients from Singapore. Conclusions: Differences exist in presentation and factors associated with ACS among patients from the United States and Singapore that may affect the performance of risk stratification tools. These findings suggest that cardiac clinical decision rules need international validation.

Clinical value of diagnostic instruments for ruling out acute coronary syndrome in patients with chest pain: a systematic review

“…Related to the time the studies were performed, appropriate reference tests were applied in all studies. In only three studies was troponin part of the reference test 10 11 22. In three studies8 26 33 the reference test was described as being interpreted without the knowledge of the result of the prediction rule.…”

“…A single study22 was derived and only a few studies10 11 22 were validated in the troponin era. This might confine the validity of earlier performed studies and limit their application in daily practice.…”

Prognostic Value of the Duke Treadmill Score for Emergency Department Patients with Chest Pain

“…ACI-TIPI is a continuous scale reported as a percentage that indicates the probability of MI, computed as a function of the following categorical variables: age, gender, chest pain as chief complaint, abnormal Q waves, ST-segment elevation, ST segment depression, T-wave elevation, T-wave inversion. Relative weights of these predictor variables are reported in the technical manual for the algorithm as log-odds ratios and the exact numerical values are reported elsewhere (14).…”

Prognostic utility of the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI)

“…Based on ECG evidence of pathologic Q waves and ST- and T-wave changes, the software calculated a probability score for myocardial infarction, reported as a percentage, which represents the probability of acute ischemia. Exact numerical values for these log-odds ratios are reported elsewhere [30]. …”