Spontaneous Coronary Artery Dissection in Young Women Presenting with Acute Coronary Syndrome

Abstract

The pathophysiology of acute coronary syndrome (ACS) in women is complex and may involve non-atherosclerotic mechanisms. Spontaneous coronary artery dissection (SCAD) is a rare cause of ACS that predominantly affects younger women. However, limited information is available for its incidence, clinical course and outcomes compared to younger women with acute coronary syndrome (ACS) not associated with SCAD. Gender and Sex determinants of cardiovascular disease: From bench to beyond-Premature Acute Coronary Syndrome (GENESIS-PRAXY) study is multicenter prospective study of ACS patients aged 18 to 55 years. Detailed demographic, clinical, laboratory and outcome data were collected and coronary angiograms analyzed in a blinded manner. Among 383 women with ACS, 42 (11%) had SCAD confirmed by angiography. Multiple SCAD were present in 9 (21%) patients. Compared with no-SCAD patients, SCAD subjects were more likely to have absence of any cardiac risk factor (24% vs 7%, p=0.0001), lower LDL (2.5±0.9 vs 3.0±1.2 mmol/L, p=0.06) and higher HDL (2.3±4.7 vs 1.1±0.5 mmol/L p=0.0002) levels. Single vessel disease was more common (81% vs. 50%, p=0.0002) and SYNTAX score lower (8±6 vs. 12±8, p=0.002) in SCAD compared to no-SCAD patients. Coronary intervention was less commonly performed (43% vs 73%, p<0.0001) and TIMI 3 flow less commonly achieved (77% vs 93%, p=0.003) in SCAD compared with no-SCAD patients. The presence of autoimmune disease, connective tissue disorders were similar between the SCAD and no-SCAD group. Coronary hypertortuosity was identified in 95% of SCAD compared with 7% of no-SCAD patients, (p<0.0001). At 12 months follow up, SCAD patients were more likely to experience repeat hospitalization compared to no-SCAD patients (29% vs 16, p=0.04) with similar no difference in overall major adverse cardiac events (MACE). SCAD is an important and not infrequent cause of ACS in younger women. Despite a low risk factor and angiographic burden of atherosclerosis, a significant proportion of SCAD patients experience repeat hospitalization and MACE at one year. These findings underscore the need for greater understanding of SCAD mechanisms and better risk stratification for improving outcome in this high risk group.