Association of Diastolic Dysfunction with N-terminal Pro-B-type Natriuretic Peptide Level in Heart Failure Patients with Preserved Ejection Fraction.

Heart failure is a major public health issue with a current prevalence of over 23 million worldwide. Epidemiologic studies suggest that nearly one-half of patients with heart failure have a normal ejection fraction that is now termed HFpEF. Prevalence of HFpEF is approximately 50% (range 40-71%). Most pathophysiologic abnormalities in patients with HFpEF are related to diastolic function. Doppler echocardiography is the choice of investigation for evaluation of Diastolic function. Tissue Doppler Imaging is a new dimension in this concept. Natriuretitic peptides are widely accepted biomarker in HFrEF patients. Now a days, it is also considered for HFpEF patients for diagnostic & prognostic purpose. Aim of this study was to find out the association of Diastolic dysfunction with N-terminal Pro B-type Natriuretic Peptide level in HFpEF patients. This cross-sectional analytical study was conducted in the department of Cardiology in Mymensingh Medical College Hospital, Mymensingh, Bangladesh from October 2016 to September 2017. Total 120 HFpEF patients were included after considering inclusion and exclusion criteria. Sample population was divided into two groups, Group I: HFpEF patients with normal Diastolic function. Group II: HFpEF patients with diastolic dysfunction in this study mean NT-pro BNP value of Group I and Group II were 104.07±7.2pg/ml and 943.19±112.51pg/ml respectively, which was statistically significant (p value <0.05). Among the echocardiographic parameters LV hypertrophy, Left atrial volume index (LAVI), TDI derived mitral annular velocity, e' septal velocity, E/e' (septal) ratio, Decelaration time were statistically significant. In this study, it was also shown that the levels of NT-proBNP had positive correlation with Doppler parameters. Statistically significant moderate positive correlation was observed between NT-proBNP level and LAVI value, correlation coefficient (r=0.553, p=0.001) suggesting that the higher the level of NT Pro BNP level, the higher value of the LAVI value. Statistically significant moderate positive correlation was also observed between NT-proBNP level and E/e' (septal), correlation coefficient (r=0.526, p=0.001) suggesting that the higher the level of NT Pro BNP level, the Higher value of the E/e' (septal) value in HFpEF patients with diastolic dysfunction. In subgroup analysis of Group II ,mean NT-proBNP level showed affirmative relation with severity of diastolic dysfunction grades ranging from grade I (340.76±24.42) to grade III (3727.83±306.50) Diastolic dysfunction is associated with elevated NT-proBNP level in HFpEF patients & NT-proBNP value rises with gradual deterioration of Diastolic dysfunction among the HFpEF patients.