Abstract
Background
Fibromuscular dysplasia (FMD) is a common predisposing condition for spontaneous coronary artery dissection (SCAD), which is an important cause of myocardial infarction (MI) in young to middle-aged women. However, its impact on clinical presentation, coronary anatomies, and outcomes have not been reported.
Purpose
To evaluate coronary angiographic characteristics and clinical outcomes in SCAD patients with or without underlying extracoronary FMD.
Methods
We retrospectively analyzed patients enrolled in our Vancouver SCAD registries who were screened for extracoronary FMD. Extracoronary FMD was defined as the presence of multifocal FMD on catheter or noninvasive angiography (computed tomographic or magnetic resonance imaging) in ≥1 extracoronary vascular beds. We reviewed coronary angiograms for manifestations of coronary FMD that were previously described (i.e. irregular stenosis, smooth stenosis, dilatation/ectasia, and tortuosity). Severe tortuosity was defined as ≥2 consecutive bends ≥180° at any cardiac cycle or 360° loop in ≥1 epicardial artery that was ≥2 mm in diameter. Clinical outcomes of major adverse cardiovascular event (MACE), a composite of all-cause death, MI, and stroke, were evaluated.
Results
We included 346 SCAD patients, 250 (72.3%) had extracoronary FMD. Patients with FMD were older (54.6±9.5 vs. 51.7±9.8 years) and more likely to have prior history of MI (7.2% vs. 1.0%, p=0.047) and stroke (4.4% vs. 0%, p=0.081) compared with non-FMD patients. The proportion of multivessel SCAD and TIMI flow was not different between groups, but type 3 SCAD was more commonly observed in FMD group (11.6% vs. 3.1%, p=0.026). On coronary angiography, severe tortuosity was more prevalent in patients with extracoronary FMD (58.4% vs. 36.5%, p<0.001), whereas rates of irregular stenosis, smooth stenosis, and dilatation/ectasia were not significantly different (Figure). Percutaneous coronary intervention was performed in 13.2% of FMD and 15.6% of non-FMD group, with similar success rates (75.8% vs. 69.2%, p=0.65). In-hospital and long-term MACE rate at median follow-up of 1032 (IQR 453–1096) days were not different between FMD and non-FMD groups (in-hospital: 5.6% vs. 8.3%, p=0.492; long-term: 19.6% vs. 15.6%, p=0.185).
Conclusion
In SCAD patients, severe coronary tortuosity was more prevalent in patients with FMD than those without. Despite the complex coronary anatomy, FMD was not associated with worse outcomes.
Differences in coronary manifestations
Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): Canadian Institutes of Health Research
TCT-21 Thrombolysis in Spontaneous Coronary Artery Dissection: Angiographic Findings and Clinical Outcomes
