Coronary artery ectasia: new insights into pathophysiology, diagnosis, and treatment.

Coronary artery ectasia (CAE) is defined as a segment of the coronary artery that has a diameter of more than 1.5 times the normal adjacent segments. It was described many years ago, but many aspects of this phenomenon are still unknown. It can be found in 1.2-2% of patients referred for coronary angiography. Risk factors are similar to atherosclerosis, but not in all patients. Histology shows extensive destruction of the musculoelastic elements, with marked degradation of the medial collagen and elastin fibers with disruption of the internal and external elastic lamina. These patients have abnormal levels of matrix metalloproteinases and other related proteins. Yet, the actual etiology of CAE is still unknown. Advances in new and improved imaging modalities such as CT and magnetic resonance angiography enable easier and more accessible diagnosis and evaluation. Treatment is aimed mostly at common cardiovascular risk factors. In small series, CAE was associated with worse prognosis. Anticoagulation was never examined in large trials. Nitrates worsen the flow and should not be administered. Interventional treatments are also an option, but a challenging one. This review presents an update on the current knowledge on CAE.