Nonatherosclerotic coronary artery disease in young women

Background: Nonatherosclerotic coronary artery disease (NACAD) is an important cause of myocardial infarction (MI) in young women but is often missed on coronary angiography, especially spontaneous coronary artery dissection (SCAD). The prevalence of NACAD in young women has not been described.

Methods: We retrospectively reviewed all coronary angiograms of women aged 50 years and younger at Vancouver General Hospital from December 1, 2009 to November 30, 2011. The angiograms were reviewed by 2 experienced interventional cardiologists, and reported as normal (<30% stenosis), atherosclerotic coronary artery disease (ACAD), or NACAD. NACAD was further characterized as SCAD, coronary fibromuscular dysplasia (FMD), ectasia, vasculitis, embolism, congenital anomaly, or unclear etiology.

Results: Of 7605 coronary angiograms performed, 177 were done in women aged 50 years and younger. The mean age was 45.4 ± 4.9 (range, 31-50) years, 76 of 177 (42.9%) presented with acute coronary syndrome, and 66 were troponin-positive. Ninety-seven (54.8%) women had normal arteries, 54 (30.5%) had ACAD, 23 (13.0%) had NACAD, and 3 (1.7%) had unclear etiology. Of those with NACAD, SCAD was observed in 16 (all troponin-positive and 13 of 16 had noncoronary FMD), and 2 had irregular beading suspicious of coronary FMD. Coronary vasculitis was suspected in 2, and 5 had coronary ectasia. Among women with MI (66/177), 19 (28.8%) had normal arteries (3 Takotsubo cardiomyopathy), 24 (36.4%) had ACAD, 20 (30.3%) had NACAD, 16 (24.2%) had SCAD, and 3 had unclear etiology.

Conclusions: NACAD was not rare among young women (aged 50 years and younger) undergoing coronary angiography and was an important cause of MI, accounting for 30%. SCAD was the most commonly encountered NACAD in young women, causing 24% of MIs.