Hyperlipidemia after heart transplantation.

Because hyperlipidemia may be a factor in the development of late graft atherosclerosis after heart transplantation, we have studied serum lipid levels in patients during the first year after transplantation. Serum cholesterol and triglyceride levels were measured in the preoperative period and at regular intervals up to 12 months after transplantation in 22 consecutive heart transplant recipients. Patients were divided into two groups: group 1 included 10 patients with underlying ischemic heart disease, and group 2 had 12 patients with underlying idiopathic dilated or valvular cardiomyopathy. Mean serum cholesterol concentrations in both groups increased substantially after operation and peaked at 3 months (respective rises of 35% and 30%). By 12 months after transplantation 50% of group 1 and 33% of group 2 manifested a significant degree of hypercholesterolemia (plasma cholesterol greater than 6.5 mmol/L, 250 mg/100 ml). Mean serum triglyceride concentrations increased in both groups during the latter part of the first year (respective increases of 44% and 13%). At 12 months only 10% of group 1 and 8% of group 2 manifested a significant degree of hypertriglyceridemia (plasma triglycerides greater than 3.0 mmol/L, 265 mg/100 ml). Over the first postoperative year there was a progressive increase in body weight, and this correlated highly with the increase in serum lipid levels (r = 0.90 for serum cholesterol and r = 0.84 for serum triglycerides). The role of conventional risk factors including hypercholesterolemia in the development of graft atherosclerosis remains uncertain, but until their role is defined, further strenuous efforts at weight control as a means of preventing or managing hyperlipidemia need to be explored.