Hyponatraemia as a Prognostic Indicator in Acute St Elevation Myocardial Infarction

Abstract

To assess the incidence of hyponatraemia in patients with acute ST elevation myocardial infarction in Intensive Coronary Care Unit and to find out whether hyponatraemia serves as a bad prognostic indicator in acute ST elevation myocardial infarction patients. METHODS 60 patients diagnosed with Acute ST elevation Myocardial Infarction within 48 hrs. of onset of symptoms were included. Serum sodium was recorded on the day of admission. Echo with LVEF at discharge was also recorded. Outcome of the patients was recorded as either improved (with mild, moderate or severe LV dysfunction) or expired. RESULTS The average serum sodium of the 60 patients was 131.3 mEq/L with values ranging from 122-141 mEq/L. About 78.3% of patients with STEMI had hyponatraemia and patients with Anterior Wall MI had greater incidence of hyponatraemia than Inferior Wall MI. Mortality among study group was 30%. There was significant relationship between the respective serum sodium level and outcome of our patients (p = 0.0434), where hyponatraemia was found significantly among those who expired due to MI. Significant correlation existed between hyponatraemia and LV dysfunction which implied that the lower the serum sodium more severe was the LV dysfunction. CONCLUSIONS Hyponatraemia is frequently found in ST elevation myocardial infarction, particularly involving the anterior wall than inferior wall. It is strongly associated with higher Killip class of patients, more severe LV dysfunction and even more number of deaths. Hence, hyponatraemia serves as a poor prognostic indicator in Acute ST elevation myocardial infarction in short-term outlook.