Characteristics and outcomes of spontaneous coronary artery dissection of the left anterior descending artery

BACKGROUND: Spontaneous coronary artery dissection (SCAD) is an underrecognised cause of acute coronary syndrome (ACS). The left anterior descending artery (LAD) is most frequently affected, but the clinical and prognostic implications of SCAD in this location unclear. AIMS: We sought to evaluate the clinical characteristics, angiographic features, management, and outcomes of patients with SCAD involving the LAD (LAD-SCAD) using data from a nationwide registry. METHODS: The Spanish Registry on SCAD (SR-SCAD) is a prospective, multicentre registry enrolling consecutive patients with angiographically confirmed SCAD from 34 hospitals across Spain. Coronary angiograms were reviewed by a central core laboratory, and all clinical events were independently adjudicated. Primary endpoints were in-hospital major adverse events and long-term major adverse cardiovascular and cerebrovascular events (MACCE). Outcomes were compared between patients with and without LAD involvement. RESULTS: Among 388 patients (mean age 54±11.5 years), 190 (49%) had LAD involvement, after excluding 8 patients with concomitant left main extension. Compared with other vessels, LAD dissections were longer (35 mm [interquartile range [IQR] 22-50] vs 30 mm [IQR 20-40]; p=0.01), more often multivessel (16% vs 3%; p<0.001) and multisegment (30% vs 19%; p=0.024), with higher creatine kinase-myocardial band (170 U/L [IQR 112-190] vs 24 U/L [IQR 4-78]; p=0.032), lower left ventricular ejection fraction (55±5.4% vs 58±6.6%; p=0.034), and more frequently treated with percutaneous coronary intervention (27% vs 17%; p=0.027). Notably, LAD involvement independently predicted higher long-term MACCE (adjusted hazard ratio 2.00, 95% confidence interval: 1.10-3.97; p=0.046), compared with SCAD in other locations. CONCLUSIONS: LAD-SCAD identifies patients with more complex angiographic features and higher long-term risk compared with non-LAD-SCAD. Despite frequent percutaneous coronary intervention, outcomes were not improved in this high-risk LAD population, emphasising the prognostic relevance of dissection location and supporting individualised treatment.