Letter by Poullis and Pullan Regarding Article, "Frequency and Predictors of Internal Mammary Artery Graft Failure and Subsequent Clinical Outcomes: Insights From the Project of Ex-Vivo Vein Graft Engineering via Transfection (PREVENT) IV Trial".

Harskamp et al1 present interesting data with regard to left internal mammary artery (LIMA) patency in patients from the Project of Ex-vivo Vein Graft Engineering via Transfection (PREVENT) IV trial. Additional diagonal grafting was identified as a significant detrimental risk factor for LIMA patency. Their work involved 1539 patients with 12 to 18 months of follow-up (76% angiographic follow-up rate). This work raises a number of issues. The identification of diabetes mellitus as a preventative risk factor for LIMA patency in the presence of a diagonal graft may hint that …