Abstract
BACKGROUND: Spontaneous coronary artery dissection (SCAD) is an increasingly diagnosed cause of myocardial infarction. Although different SCAD angiographic classifications exist, their clinical impact remains unknown. AIMS: The aim of this study was to evaluate the relationship between an angiographic classification and the development of adverse clinical events during the follow-up of a large, unselected cohort of patients with SCAD. METHODS: We conducted an observational study of consecutive SCAD patients from 26 centres across Italy and Spain. Cases were classified into five different angiotypes according to the latest classification endorsed by the European Society of Cardiology. The main composite endpoint included all-cause death, non-fatal myocardial infarction (MI), and any unplanned revascularisation. RESULTS: In total, 302 SCAD patients (mean age 51.8±19 years) were followed up for a median of 22 months (IQR 12-48). At 28 days, the composite outcome was higher for the angiotypes with a circumscribed contained intramural haematoma (2A and 3): 20.0% vs 5.4%, p<0.001 (non-fatal MI: 11.0% vs 3.5%, p=0.009; unplanned revascularisation: 11.0% vs 2.5%, p<0.001). This was sustained during follow-up (24.5% vs 9.9%, p=0.001). There were no differences in mortality (0.3% overall). The presence of an angiotype 2A or 3 was an independent predictor of a higher incidence of the composite outcome (adjusted HR 2.44, CI: 1.24-4.80, p=0.010). CONCLUSIONS: The SCAD angiographic classification correlates with outcome. Those presenting with an angiographically circumscribed contained intramural haematoma (angiotypes 2A and 3) showed an increased risk of short-term adverse clinical events that was maintained during follow-up.