Data regarding emergency department (ED) assessment of acute chest pain (CP) and incidence of myocardial infarction (MI) among adult congenital heart disease (ACHD) patients, relative to the non-congenital population, is lacking.

To describe MI risk in ACHD patients presenting to the ED with chest pain and to compare clinical characteristics, diagnostic testing patterns, and outcomes to controls.

We retrospectively identified a cohort of ACHD patients presenting with acute CP and matched them with non-ACHD controls at a large tertiary-level ED during the period 1998–2018.

The congenital and control cohorts comprised 297 patients respectively. While MI was less common among ACHD patients (5.2%) than controls (19.7%), P = .01, arrhythmia (14% vs 6%, P < .001) and acute heart failure (3% vs 0.3%, P = .02) were more often the cause of symptoms. Despite more often presenting with non-anginal CP (81% vs 66%, P < .001) and having fewer CAD risk factors (P = .03), ACHD patients underwent more frequent stress testing (22% vs 14%, P < .001) and underwent invasive coronary angiography with equal frequency (7% vs 8%, P = .99). The trend of greater diagnostic scrutiny for acute coronary disease, in the absence of increased risk, strongly correlated with degree of congenital complexity. Both CP character and HEART Score reliably predicted MI for ACHD patients and controls (both P < .001).

MI is an uncommon cause of CP among ACHD patients presenting to the ED and occurs less frequently than seen in the general population. Established MI predictors, CP character and HEART Score, can reliably identify MI in ACHD patients.