High incidence of adverse events in spontaneous coronary artery dissection patients during mid-term follow-up: a persistent challenge ahead

Background: Spontaneous coronary artery dissection (SCAD) is an emerging cause of acute coronary syndrome (ACS), disproportionately affecting women. Data on the management and outcomes of these patients remain limited, especially regarding the overall risk of major adverse cardiovascular events (MACE) and arrhythmic complications. This study aimed to investigate the incidence and independent predictors of MACE in SCAD patients. Methods: In this single-center, prospective observational study, 76 patients with SCAD were enrolled. Clinical follow-up (mean duration: 4.03±3.4 years) was conducted through in-hospital visits and electronic database monitoring. The primary composite endpoint included MACE, defined as cardiovascular (CV) rehospitalization and death, the secondary endpoint included supraventricular and ventricular arrhythmias. Results: All the patients enrolled were characterized by their clinical presentation, underlying risk factors, and triggers for SCAD. Of the 76 patients, 45 (59.2%) received medical therapy alone, 27 (35.5%) underwent percutaneous coronary intervention (PCI), and four (5.2%) had coronary artery bypass grafting (CABG). During the follow-up period, the primary endpoint occurred in 34 patients (44.7%), with CV rehospitalization as the main cause of MACE (31 patients, 40.8%). Coronary revascularization emerged as the only independent predictor of MACE (HR=1.92, 95% CI 1.13-3.21, P=0.035). The secondary endpoint occurred in 13 patients (17.1%). Conclusions: Although SCAD is often considered a rare and relatively benign cause of ACS, our findings reveal a high rate of CV rehospitalization and mortality. Furthermore, mid-term follow-up indicates that SCAD is associated with supraventricular and non-sustained ventricular arrhythmias, with limited impact on prognosis and generally requiring pharmacological optimization.