Determinants of Late Potentials in Acute Myocardial Infarction Patients

Background: Ventricular tachyarrhythmia increases the risk of mortality after acute myocardial infarction. One of the recommended noninvasive techniques for ventricular arrhythmia risk stratification in post-myocardial-infarction patients is detecting late potentials (LP) in signal averaged-electrocardiography (SA-ECG). This study aims to determine the prevalence of LP and to identify the determining factors of LP in Indonesian acute myocardial infarction patients. Subjects and methods: This cross-sectional study was conducted from December 2019 to April 2020 at Cipto Mangunkusumo National General Hospital, Jakarta, Indonesia. Data were collected via interviews and observation and/or obtained from the medical records provided in our unit. SA-ECG recordings were taken in the first 48 hours and the fifth day after the onset of chest pain. Independent variables were gathered during the patients' stay in the hospital. Results: We observed 53 subjects, in whom the prevalence of LP was 34%. The proportion of LP was higher in subjects with prior myocardial infarction (50% vs. 30.2%; p = 0.205), left ventricle hypertrophy (37.5% vs. 31.0%; p = 0.621), diabetes mellitus (35.3% vs. 33.3%; p = 0.563), decreased eGFR (40% vs. 31.6%; p = 0.560), hypertension (83.3% vs. 19.2%; p = 0.026), hypokalemia (28.6% vs. 15.6%; p = 0.555), hyperkalemia (100% vs. 31.4%; p = 0.111), hypomagnesemia (100% vs. 30%; p = 0.035), and hypocalcemia (41.5% vs. 15.4%; p = 0.095). In bivariate analysis, hypertension and hypomagnesemia were associated with LP. In multivariate analysis, hypertension was associated with increased risk of LP (p = 0.031; OR = 3.900; 95%CI: 1.136-13.387). Conclusion: Hypertension is a risk factor for LP.