Coronary artery bypass grafting (CABG) has prognostic benefit in patients with severe coronary disease and left ventricular dysfunction. It is particularly important in diabetic patients where CABG confers greater long term protection against coronary events than percutaneous angioplasty. However, up to 32% of saphenous vein grafts (SVGs) and 31% of radial artery grafts (RAGs) may be non-patent by one year.¹ Hypertriglyceridaemia is associated with increased mortality after CABG, particularly among diabetics, but its relation to early graft patency is unknown.^2,3 We investigated the association between metabolic risk factors and early graft occlusion by using non-invasive computed tomography (CT) angiography.

METHODS

The study was approved by the institutional review board ethics committee. All patients attending a preoperative clinic for elective CABG between October 2002 and January 2004 in sinus rhythm with normal serum creatinine, but without a history of intravenous contrast allergy, were invited to participate. Written informed consent was obtained. Of 94 consecutive participants, 14 were subsequently excluded: two died postoperatively, one had a stroke, three developed renal impairment, and eight withdrew from the study.

Recorded baseline characteristics were age, sex, history of smoking, hypertension (blood pressure > 140/90 mm Hg or pharmacological treatment for hypertension), hypercholesterolaemia (fasting cholesterol > 5.5 mmol/l or taking a cholesterol lowering agent), diabetes, and body mass index (BMI). Fasting preoperative total, low density lipoprotein, and high density lipoprotein cholesterol, triglycerides, glucose, insulin, C reactive protein, haemoglobin A_1c, fibrinogen, activated partial thromboplastin time, and white cell count were measured at a government certified laboratory. Insulin resistance and pancreatic β cell secretory capacity were calculated by means …