Local prediction score for MACE helps reduce needless tests, admissions

Researchers in Singapore have developed the age, coronary risk factors (CRF), sex, and symptoms (ACSS) risk score that can identify patients who are not at risk for major adverse cardiac events (MACE).

“The ACSS risk score shows potential for use in the local emergency department (ED) or primary care setting, potentially reducing unnecessary cardiac investigations and admission,” the researchers said.

Specifically, patients with no history of dyslipidaemia or random low-density lipoprotein (LDL) ≥2.6 mmol/L, currently treated diabetes mellitus or random glucose ≥11.1 mol/L, current smoking status, or history of myocardial infarction have a very low risk of MACE.

Of the 1,689 participants, 172 (10.2 percent) and 200 (11.8 percent) had MACE within 30 days and 1 year, respectively. The following symptoms predicted MACE: central chest pain, radiation to the jaw or neck, associated diaphoresis, and symptoms aggravated by exertion and relieved by glyceryl trinitrate. [Singapore Med J 2024;65:397-404]

The ACSS score did better than the EDACS* in predicting MACE, with an area under the curve of 0.769 (95 percent confidence interval [CI], 0.735‒0.803) for 30-day MACE and 0.760 (95 percent CI, 0.727‒0.793) for 1-year MACE.

“Our findings challenge some assertions about the value of individual symptoms in patients presenting with chest pain to the ED, as not all symptoms known to be ‘typical’ of cardiac chest pain may have significant diagnostic value in our population,” the researchers said.

“[S]ymptoms that have been reported to be predictive of MACE, such as duration, character of chest pain, radiation to one or both the arms, associated vomiting, and chest pain worse than usual angina or same as previous acute myocardial infarction, were not significant after statistical analysis,” they added.

These results were consistent with those found in studies carried out in European and other Asian settings. [Resuscitation 2010;81;281-286; J Gen Intern Med 2021;36;1514-1524; Ann Emerg Med 2016;68;93-102.e1]

Typical symptoms

In the current study, nearly “13 percent of patients with MACE had none of the typical symptoms, and about 73 percent of patients who did not have MACE had at least one of the typical symptoms,” the researchers said. “From these findings, we derived the ACSS risk score, which could identify patients in the very-low-risk band who may not require additional troponin T tests.”

In addition, the researchers modified the CRF component of the HEART** score to fit the local population and recommended a HEART score cutoff of ≤2 with a negative predictive value of ≥99.4 percent for 30-day and 1-year MACE.

“An ACSS score of ≥34, a modified HEART score of ≥6, or a troponin score of ≥1 gave a positive predictive value of about 70 percent for both 30-day and 1-year MACE,” the researchers said. “These patients should be admitted for further aggressive evaluation and management.”

In this study, the researchers enrolled patients with chest pain and nondiagnostic 12-lead ECG who presented to the ED and recorded clinical history in a predesigned template. They also measured the participants’ glucose and LDL levels and performed serial cardiac troponin tests.

The ACSS risk score was derived using results of the multivariate analysis, considering age, CRF, sex, and symptoms. Patients were then classified into very low, low, moderate, and high risk for MACE.

*ED Assessment of Chest Pain Score 

**history, electrocardiogram, age, risk factors, troponin