# Elevated Major Adverse Cardiac Event (MACE) Risk With a HEART Score of 3: A Single-Site Retrospective Validation Study

## TL;DR

A HEART score of 3 is linked to a higher risk of serious cardiac events than previously thought, suggesting caution in patient discharge decisions.

## Contribution

This study validates the HEART pathway in an urban academic ED and identifies elevated MACE risk at a HEART score of 3.

## Key findings

- A HEART score of 3 or less was associated with a 4.4% MACE rate, exceeding the traditional low-risk threshold.
- The HEART score correlated with MACE outcomes (ρ = 0.223, p < 0.001).
- Age correlated with HEART scores but not directly with MACE outcomes.

## Abstract

Objective: The HEART pathway is a widely used clinical decision-making tool to risk-stratify patients presenting with chest pain in the emergency department (ED). A HEART score of 0-3 is generally accepted as “low risk,” often serving as a threshold for safe discharge. This study aimed to evaluate the performance of the HEART pathway in an urban academic ED and determine the associated rate of major adverse cardiac events (MACE) at a HEART score of 3. MACE were defined as all-cause mortality, cardiovascular death, myocardial infarction, heart failure hospitalization, or stroke within 90 days.

Methods: We conducted a retrospective chart review of 1,284 ED visits for chest pain from September 1, 2017, to August 31, 2018, at Louisiana State University Health Shreveport (LSUHS), Shreveport, Louisiana. HEART scores, demographics, and 90-day MACE outcomes were collected and analyzed using non-parametric statistical methods.

Results: Of 1,284 patients, 79 (6.2%) experienced MACE. Among patients with a HEART score of 3 or less, the MACE rate was 4.4% using Wilcoxon's rank-sum test (p < 0.001). The HEART score showed a positive correlation with MACE using Spearman’s rank correlation coefficient (ρ = 0.223, p < 0.001). Age correlated moderately with the HEART score (ρ = 0.568), but not with MACE. Gender showed no significant correlation with either HEART score or MACE outcomes.

Conclusion: A HEART score of 3 was associated with a MACE rate higher than the traditionally accepted 2% threshold for low risk. Clinicians should approach disposition decisions for these patients with caution and consider shared decision-making and observation. Further research is needed to refine HEART score interpretation at this critical threshold.