Internal Thoracic Artery vs. Vein Grafts - Postoperative Angiographic Findings in Symptomatic Patients after 1000 Days - Gansera, B; Schiller, M; Kiask, T; Angelis, I; Neumaier-Prauser, P; Kemkes, B M (The Thoracic and Cardiovascular Surgeon, 2003)