Cardiovascular Diabetology (Nov 2009)
Elevated plasma levels of TNF-alpha and Interleukin-6 in patients with diastolic dysfunction and glucose metabolism disorders
Abstract
Abstract Background Diabetes mellitus (DM) has reached epidemic proportions and is an important risk factor for heart failure (HF). Left ventricular diastolic dysfunction (LVDD) is recognized as the earliest manifestation of DM-induced LV dysfunction, but its pathophysiology remains incompletely understood. We sought to evaluate the relationship between proinflammatory cytokine levels (TNF-alpha, IL-6) and tissue Doppler derived indices of LVDD in patients with stable coronary artery disease. Methods We enrolled 41 consecutive patients (mean age 65+/-10 years) submitted for coronary angiography. Echocardiographic assessment was performed in all patients. Pulsed tissue Doppler imaging was performed at the mitral annulus and was characterized by the diastolic early relaxation velocity Em. Conventional transmitral flow was measured with pw-doppler. Early (E) transmitral flow velocity was measured. LVDD was defined as E/Em ratio ≥ 15, E/Em 8-14 was classified as borderline. Plasma levels of TNF-alpha and IL-6 were determined in all patients. A standardized oral glucose tolerance test was performed in subjects without diabetes. Results Patients with E/Em ratio ≥ 15, classified as LVDD and those with E/Em ratio 8-14 (classified as borderline) had significantly higher IL-6 (P = 0,001), TNF-alpha (P Conclusion This study reveals that increased plasma levels of IL-6 and TNF-alpha were associated with LVDD. These findings suggest a link between low-grade inflammation and the presence of LVDD. An active proinflammatory process may be of importance in the pathogenesis of diastolic dysfunction.