Objective: To evaluate the relationship between myocardial energy expenditure (MEE) level and cardiac function in chronic heart failure (CHF) patients.
Methods: A total of 99 CHF patients were divided into 3 groups according to the LVEF (HFNEF > or = 50%, n = 37; HFREF1 35.1% - 49.9%, n = 30; HFREF2 < or = 35%, n = 32) or the New York Heart Association (NYHA II, n = 26; III, n = 42; IV, n = 31) criteria. Thirty patients with cardiovascular disease and without CHF served as controls. Routine examinations including serum CRP (ELISA) and plasma NT-proBNP (chemiluminescence sandwich ELISA) were made on the next morning after admission; echocardiography was performed on the third day after admission. LVMW, LVMWI, RWT, LVIDd, LA, LV, LVEF, LVFS, E/A, EDT, IVRT, Tei index and MEE were measured or calculated.
Results: MEE was significantly higher in HFREF patients than in controls (P < 0.01) and similar between HFNEF patients and controls (P > 0.05). MEE increased in proportion to decrease of LVEF and increase of NYHA grades in CHF patients (all P < 0.05). Bivariate analysis confirmed that MEE was significant correlated with LVMW, LVMWI, RWT, LVIDd, LA, LV, LVEF (r = -0.540, P < 0.01), LVFS (r = -0.454, P < 0.01), E/A, EDT, IVRT, Tei index, NYHA grades, CRP and NT-proBNP.
Conclusion: MEE derived from standard echocardiographic measurements is an effective indicator for myocardial bioenergetics and significantly correlated with cardiac function in CHF patients, especially in CHF patients with reduced LVEF.