Morphology and patency of Gore-Tex wrapped internal mammary artery bypass-evaluation with helical CT

Objective: To determine the patency of coronary internal mammary artery bypass (IMAB) with CT-angiography (CTA) and to evaluate the morphology of a covering Gore-tex IMAB-sleeve (PIMAS) used to protect the bypass at possible reoperation. Materials and Methods: Sixty-five patients with IMAB wrapped with PIMAS (67 grafts) were prospectively investigated by CTA for bypass patency and sleeve morphology 6 months postoperatively with a standardised radiological and clinical protocol. Results: All patent bypass arteries (62/62) were identified by CTA as open. In the remaining five cases, CTA revealed a bypass occlusion, which could be proven by coronary angiography in two cases (two patients refused angiography, one bypass was open angiographically). Morphology of the PIMAS could be imaged exactly in all cases. Sleeve implantation did not lead to adverse effects in terms of bypass occlusion or compression. In four patients, additional clinically relevant information were achieved. Conclusion: PIMAS implantation proved to be a safe procedure with good short-term results. CTA is a valuable method to exclude occlusion of sleeved IMA bypasses. Depiction of the wrapped IMAB by CTA supplies important information for preparing strategy in case of reoperation.