Can BNP levels and Killip grading assess the severity of injury to myocardium after acute myocardial infarction in Type II Diabetics?

Abstract

Introduction: Post myocardial infarction risk assessment and stratification is done clinically using Killip Scale as well as biochemically by measuring plasma B-type Natriuretic Peptide (BNP) levels.
Objective: To compare the validity of the two diagnostic modalities in type II diabetic patients who had recently suffered from acute myocardial infarction (AMI).
Materials & Methods: This descriptive cross-sectional study was conducted on 196 type II diabetic patients admitted after first episode of AMI in the Department of Cardiology at Rehman Medical Institute (RMI) and Lady Reading Hospital (LRH) Peshawar from 1st November 2014 to 30th June 2015 through convenience sampling. The subjects were divided into two groups; optimal control group and sub-optimal control group on the basis of HbA1c levels. Blood samples were taken and analyzed for HbA1c and BNP levels. Killip scale grading and echocardiography were recorded. Post MI risk assessment was done by Killip scale as well as by plasma BNP levels. SPSS version 16.0 was used to analyze the data for descriptive and comparative statistics, keeping p≤0.05 significant.
Results: Significant difference (p<0.001) in the BNP levels were observed between optimal and suboptimal control groups with severe heart disease who had plasma BNP level of more than 900 pg/ml (5.71% vs 17.39%). No association was found between glycemic control and Killip scale grading (p>0.05). There was also no significant difference in classes (II, III and IV based on Killip scale grading) between two groups.
Conclusion: High BNP levels were recorded in post MI patients in both the groups whereas the Killip Scale grades did not differ significantly in BNP levels in post MI patients.