INTRODUCTION: Coronary sclerosis is a risk factor for the progression to obstructive coronary artery disease (CAD). However, understanding its impact on the outcomes of patients with myocardial infarction and non-obstructive coronary arteries is limited. This study aimed to explore the prognostic influence of coronary sclerosis on in- and out-of-hospital events in troponin-positive patients with non-obstructive coronary arteries.

METHODS: This study was a retrospective cohort analysis based on prospectively collected data. A total of 24,775 patients who underwent coronary angiography from 2010 to 2021 in a German university hospital were screened, resulting in a final study cohort of 373 troponin-positive patients with non-obstructive coronary arteries and a follow-up period of 6.2 ± 3.1 years. Coronary sclerosis was defined as coronary plaques without angiographically detectable stenotic lesions of 50% or more in the large epicardial coronary arteries. The primary study endpoint was the occurrence of in-hospital events. Secondary endpoints included events during follow-up.

RESULTS: Patients with coronary sclerosis were significantly older (70 ± 12 vs. 58 ± 16 years, p < 0.001), had ST-segment elevation less frequently on electrocardiogram (9.4% vs. 18.7%, p = 0.013), and suffered more often from diabetes mellitus (23.3% vs. 13.1%, p = 0.009), arterial hypertension (79.6% vs. 59.8%, p < 0.001), chronic obstructive pulmonary disease (17.1% vs. 9.4%, p = 0.028), chronic kidney disease (22.2% vs. 8.4%, p < 0.001), atrial fibrillation (19.8% vs. 12.2%, p = 0.045), and valvular diseases than patients without CAD. Patients with coronary sclerosis were more likely to receive medication for primary/secondary prevention on admission and at discharge. The incidence of in- and out-of-hospital events was significantly higher in patients with coronary sclerosis (in-hospital: 42.8% vs. 29.9%, p = 0.010; out-of-hospital: 46.0% vs. 26.1%, p < 0.001). Mortality rates tended to be higher in the coronary sclerosis group (29.4% vs. 20.0%, p = 0.066).

CONCLUSION: Patients diagnosed with coronary sclerosis presented a higher incidence of comorbidities and increased medication use, and experienced higher rates of both in-hospital and out-of-hospital events, primarily due to the clustering of cardiovascular risk factors.