Heart failure in diabetes mellitus: causal and treatment considerations

The metabolic abnormalities associated with diabetes mellitus result in macrovascular and microvascular complications in multiple organ systems; it is the cardiovascular impact that accounts for the greatest morbidity and mortality associated with this disease. Heart failure, both with reduced and preserved systolic function, is a major complication, arising from the frequent associations with coronary atherosclerosis, hypertension, and a specific heart muscle dysfunction (cardiomyopathy) that occurs independently of coronary artery disease. Hyperglycemia, insulin resistance, and hypertension, together with activation of both circulating and tissue renin-angiotensin-aldosterone systems, contribute to structural fibrosis and autonomic neuropathy. Thus it becomes imperative to identify cardiac abnormalities early in the course of both type 1 and type 2 diabetes in order to allow early and aggressive intervention to control glucose and blood pressure and to normalize blood lipid profiles. Patients with diabetes should be treated to secondary prevention targets, including blood pressure less than 130/80 mm Hg and LDL less than 100 mg/dL. Angiotensin converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, certain calcium channel blockers, statins, and aspirin have all been demonstrated to significantly reduce cardiovascular morbidity and mortality in patients with diabetes.