Effects Of L-carnitine On Heart Failure With Preserved Ejection Fraction

Objective:To explore the effects of L-carnitine on improving the diastolic function and the exercise endurance in heart failure patients with preserved ejection fraction(HFPEF) using echocardiographic indices, the level of brain natriuretic peptide (BNP) and the6-minute walk test(6-MWT).Methods:A total of121cases admitted in our department and diagnosed as HFPEF in our department were enrolled from May2011to October2012(58men and63women, average age72.4±7.21years old). All the patients met the criteria according to the consensus statement on the diagnosis of heart failure with normal left ventricular ejection fraction by the Heart Failure and Echocardiography Associations of the European Society of Cardiology(ESC)2007and the Chinese expert consensus on diagnosis and treatment on heart failure with normal ejection fraction2010. The criteria were as follows:①age>50years old,②performance of symptoms and signs of heart failure,③presence of normal or only mildly abnormal left ventricular systolic function (LVEF>45%), LVEDI<97ml/m2,④echocardiographic evidence of diastolic dysfunction, E/E’≥8,⑤with a history of NYHA class Ⅱ-Ⅳ;⑥the BNP>200pg/ml or the NT-proBNP>220pg/ml. Exclusion criteria were as follows:②with a history of ejection fraction<45%in the past;②COPD, valve disease, pericardial diseases, Restrictive cardiomyopathy, hypertrophic cardiomyopathy and isolated right heart failure caused by other reasons;③with a history of acute myocardial infarction in the latest month;④tumor, hematonosis, autoimmune illness, recent surgery trauma, acute or chronic infections;⑤hepatic or renal insufficiency;⑥allergic to L-carnitine.All the cases were divided into two groups randomly, the L-carnitine group (61eases) and the control group (60cases). Basic treatments were given to all patients according to their conditions. Furthermore, the patients in L-carnitine group were given L-carnitine5.0g daily intravenously for14days. Echocardiographic parameters including E/A, E/E1, LA, and DT, the level of BNP and the6-MWT were measured before treatment and14days after treatment. SPSS16.0was used as the statistical software package. P<0.05was considered statistically significant.Results:1There was no significant difference between the L-carnitine group and the control group in baseline data, such as sex, age, diabetes, hypertension, coronary disease, smoking, dyslipidemia, drinking histories, atrial fibrillation and the blood pressure, heart rate, NYHA class, blood biochemical tests, the level of BNP, echocardiographic parameters (E/A, E/E’, LA, and DT) and the6-MWT.(all P>0.05)2After treatment, the E/A ratio in the L-carnitine group is significantly higher than before(0.75±0.16vs.0.85±0.19, P<0.05), but there was no significant difference compared with the control group after treatment (0.85±0.19vs.0.81±0.16, P>0.05).3There was no significant difference in LA size of L-carnitine group between the before and after treatment (42.4±3.9mm vs.41.2±3.6mm, P>0.05). At14days after treatment, there was also no significant difference in LA size between the two groups(41.2±3.6mm vs.42.2±3.9mm, P>0.05).4After treatment DT showed no significant difference compared with before treatment in L-carnitine group (295.3±70.31ms vs.284.5±68.8ms, P>0.05), and there was no significant difference between the two groups after treatment (284.5±68.8ms vs.291.2±75.2ms, P>0.05).5E/E1ratio in the L-carnitine group is significantly lower14days after treatment than before treatment (15.21±6.11vs.10.3±4.05,P<0.05), and there was significant difference between the two groups after treatment (10.3±4.05vs.12.8±4.15,P<0.05).6The level of BNP was lower in L-carnitine group14days after treatment than before treatment (528.2±97.2pg/ml vs.171.8±75.2pg/ml, P<0.05),and there was significant difference between the two groups after treatment in BNP(171.8±75.2pg/ml vs.238.9±89.2pg/ml, P<0.05).7After treatment the results of6-MWT showed significantly improvement than before in L-carnitine group (344.8±12.7m vs.444.5±18.6m,P<0.05), and there was significant difference between the two groups after treatment (444.5±18.6m vs.398.2±17.8m,P<0.05).8There was no significant difference in incidence of all MACE between the two groups during their hospitalization (8.2%vs.10%, P=0.73).Conclusion:L-carnitine can improve the diastolic function and the exercise endurance in heart failure patients with preserved ejection fraction effectively...