Soluble CD40 ligand in acute and chronic heart failure.

AIMS: Inflammatory cytokines may play a pathogenic role in heart failure (HF). CD40-CD40 ligand (CD40L) interactions are important in atherogenesis and based on its role in inflammation we sought to evaluate the role of CD40L in human HF. METHODS AND RESULTS: Serum levels of soluble (s) CD40L were measured in 236 patients with acute HF following myocardial infarction, treated with either angiotensin-converting enzyme (ACE)-inhibition or angiotensin II blockade and followed for 2 years, and in 116 patients with chronic HF. Our main findings were: (i) patients with acute HF had increased sCD40L levels, particularly those with severe HF, diabetes, or hypertension; (ii) when these patients were followed longitudinally, persistently raised sCD40L levels were found throughout the observation period with no effect of captopril or losartan; (iii) the increase in sCD40L during follow-up was not seen in patients receiving warfarin therapy; (iv) patients with chronic HF also had raised sCD40L, significantly correlated with clinical severity, neurohormonal dysregulation, and left ventricular dysfunction; (v) studies from different blood compartments suggest that the vasculature of lower extremities and the failing myocardium itself may produce and secrete sCD40L in chronic HF. CONCLUSION: Our findings may suggest a pathogenic role for enhanced CD40-CD40L interactions in human HF.