Comparison of Ruptured Plaques in Native Coronary Arteries and in Saphenous Vein Grafts: An Intravascular Ultrasound Study

Intravascular ultrasound (IVUS) has been used to describe ruptured plaques in saphenous vein grafts (SVGs) and native coronary arteries. We compared clinical, angiographic, and IVUS features of ruptured atherosclerotic plaques in SVGs and native coronary arteries. We identified 95 plaque ruptures in 76 SVGs in 73 patients. These lesions and patients were matched with 95 lesions and patients from a database of 468 native artery ruptures. The matching criterion was IVUS mean reference lumen area. Patients with ruptured SVG plaques were older (68.4 ± 10.1 vs 65.0 ± 10.6 years, p = 0.021), more often had hypercholesterolemia (92% vs 74%, p = 0.015) and hypertension (78% vs 62%, p = 0.059), and more often had a history of a remote myocardial infarction (57% vs 32%, p = 0.002). In contrast, anginal symptoms were similar in the 2 groups (70% to 75% of each group had an acute coronary syndrome). Most (90% to 95%) ruptured plaques in each group were classified as angiographically complex. However, ruptured SVG lesions more often had an angiographically visible intimal flap (71% vs 38%, p <0.001). More than 70% of lesions in the 2 groups had positive arterial remodeling by IVUS, but there was a tendency for a higher remodeling index in ruptured plaque SVG lesions (1.18 ± 0.30 vs 1.11 ± 0.20, p = 0.085). The site of the initial tear occurred mainly (in ∼70%) at the plaque shoulders in the 2 groups. In conclusion, although patients with SVG plaque ruptures are older and have more co-morbidities, the clinical presentation and angiographic and IVUS features are remarkably similar to those of native artery plaque ruptures.