Usefulness of B-Type Natriuretic Peptide in Predicting the Involvement of Right Ventricle in Acute Inferior Wall Myocardial Infarction OC01-OC04
Dr. Victor Ashok,
7D, KG Towers, 100 Feet Bypass Road, Velachery, Chennai-600042, Tamil Nadu, India.
Introduction: Cardiovascular Disease (CVD) is the leading cause of deaths globally as, the death rates due to CVD has increased from 26% in 1990 to 29.5% in 2010. The acute coronary syndrome includes acute Myocardial Infarction (MI) with ST segment elevation, Non-ST Segment Elevation Myocardial Infarction (NSTEMI) and Unstable Angina (UA). Isolated infarction of the Right Ventricle (RVMI) is rare and is commonly associated with Inferior Wall MI (IWMI) or Posterior Wall MI (PWMI). B-type natriuretic peptide is one of the biomarkers which have been evaluated during acute MI.
Aim: In this study, the usefulness of B-Type Natriuretic Peptide (BNP) in predicting the involvement of RV in acute ST elevation with Inferior Wall MI (IW MI) and PW MI was assessed.
Materials and Methods: The study was a prospective observational study, done on 64 patients less than 60 years of age. The study was conducted over a period of four months at Rajiv Gandhi General Hospital, Madras Medical College, Chennai. The patients with diagnosis of IW MI, IW with RVMI, IW with PW myocardial infarction (PWMI), Inferior & PW with RVMI were included. BNP levels, LVEF and troponin I were measured. Killip class was also observed and patients were classified and compared against different levels of BNP.
Results: When RV, PW & RV with PW was involved in IWMI, BNP level was increased to more than 900pg/ml, than in isolated IWMI. This increment was statistically significant. There was severe increase in BNP in those having Left Ventricular Ejection Fraction (LVEF) =30%, and majority of patients in the range of 30-50%. All the patients in Killip class III & IV had severe BNP increase as did those patients with cardiac Troponin levels between the range of 2-4ng/ml.
Conclusion: All the findings are statistically significant and prove that severe BNP increase in acute IW MI is definitely a predictor of either RV, PW & RV with PW involvement. LVEF has a significant inverse correlation with BNP levels, as the BNP raises, LVEF shows a steady decline. Killip class also shows a poor prognosis with elevated BNP. Troponin I levels are higher with increase in BNP.