Spontaneous Coronary Artery Dissection: Pitfalls of Angiographic Diagnosis and an Approach to Ambiguous Cases

Spontaneous coronary artery dissection (SCAD) is a pathophysiologically distinct cause of acute coronary syndromes (ACS). It is increasingly recognized that optimal management is different from that for atherosclerotic ACS and that a SCAD diagnosis has specific long-term prognostic and therapeutic implications. Accurate diagnosis is therefore essential to ensure the best treatment of patients. At present this relies on the recognition of typical features of SCAD identified on invasive coronary angiography. Although most SCAD can be readily distinguished angiographically from alternative causes of ACS, false positive and false negative diagnoses remain common. In particular, sometimes non-SCAD presentations, including atherothrombosis, takotsubo cardiomyopathy, coronary embolism, coronary vasospasm, contrast streaming, and myocardial infarction with nonobstructive coronary arteries, can mimic angiographic features usually associated with SCAD. The authors present the combined experience from European and US SCAD referral centers reviewing the classical angiographic appearances of SCAD, presenting potential diagnostic pitfalls and exemplars of SCAD mimickers. The authors further review the benefits and limitations of intracoronary imaging in the context of SCAD. Finally, the authors discuss the investigation of ambiguous cases and an approach to minimize misdiagnosis in difficult cases.