Images in CAD
A 57-year-old woman presented to an outside hospital with sudden onset anginal pain at rest, radiating to the left arm. Initial ECG showed ST elevations in the anterior leads. Her pain improved but did not resolve with nitroglycerin and aspirin. Emergent invasive coronary angiography revealed abrupt narrowing and diffuse irregularity of the distal left anterior descending, which did not improve with intracoronary nitroglycerin and nicardipine. At the time, the etiology of the event was uncertain, and treatment for a possible thrombotic coronary event was initiated with dual antiplatelet therapy, statin, angiotensin-converting enzyme inhibitor, and β-blockade. Serum troponin peaked at 22.5 ng/ml. Two months later, she was referred to our hospital for further evaluation at which time a coronary computed tomography angiography (CTA) was requested.
CTA demonstrated sequelae of an apical left ventricular infarction (Fig. 1), also corroborated by cardiac ultrasound (not shown), but did not reveal evidence of any calcified or noncalcified atherosclerosis. No severe stenosis was identified. Given the uncertainty around the diagnosis and discordant findings, previous invasive angiography images were requested for comparison, which showed an abrupt distal left anterior descending caliber change, tortuosity, subtle luminal irregularity and serially beaded lumen (Fig. 2). These findings were then identified on the CTA and had improved in the interim period (Fig. 2). The possibility of a coronary artery dissection was raised. An abdominopelvic CTA was requested, which demonstrated beaded renal arteries with serial aneurysms, and a tortuous aortoiliac system (Fig. 3).
Spontaneous coronary artery dissection (SCAD) is an infrequent cause of acute coronary syndrome. Retrospective studies report a detection rate of SCAD in 0.07–1.1% of all coronary angiograms 1. SCAD typically affects young, otherwise healthy patients, with a strong female preponderance (female : male=4 : 1) 2. There is clear association with peripartum or postpartum status along with underlying vasculitides such as fibromuscular dysplasia (FMD), connective tissue disorders such as Ehlers–Danlos syndrome, and exercise 1,3. Notably, in one study, incidental FMD of the iliac artery was detected in as many as 50% of SCAD patients at the time of coronary catheterization 1. Furthermore, FMD may be detected in an even greater proportion of these patients if more extensive vascular imaging is undertaken, as FMD, a nonatherosclerotic, noninflammatory vascular disease, is known to frequently involve the renal and carotid arteries. This strong association suggests that vascular screening for FMD should be considered in all patients with SCAD, and in this case multimodality imaging of multiple vascular beds helped to establish the correct diagnosis with greater certainty.
The optimal treatment strategy for acute SCAD remains indeterminate. However, there is evidence that conservative management often leads to favorable outcomes, while percutaneous coronary intervention is associated with high rates of complication and procedural failure. Ten-year recurrence rates for SCAD reach 29% with a mean time interval of 2.8 years, stressing the importance of ongoing surveillance 1. Coronary CTA may play an important role in noninvasive diagnosis as well as in ongoing surveillance after the initial diagnosis.
Conflicts of interest
There are no conflicts of interest.
1. Tweet MS, Hayes SN, Pitta SR, Simari RD, Lerman A, Lennon RJ, et al.. Clinical features, management, and prognosis of spontaneous coronary artery dissection. Circulation 2012;126579–588
2. Hayes SN. Spontaneous coronary artery dissection (SCAD): new insights into this not-so-rare condition. Tex Heart Inst J 2014;41295–298
3. Saw J, Ricci D, Starovoytov A, Fox R, Buller CE. Spontaneous coronary artery dissection: prevalence of predisposing conditions including fibromuscular dysplasia in a tertiary center cohort. JACC Cardiovasc Interv 2013;644–52