Echocardiographic evaluation of mitral inflow e wave velocity-to-tissue Doppler e’ wave velocity ratio (E/e’) as a prognostic indicator in ST-elevation myocardial infarction

Abstract AIMS AND OBJECTIVES: To study the clinical characteristics and to assess the usefulness of echocardiographic evaluation of mitral inflow E wave velocity-to-tissue Doppler e’ wave velocity ratio (E/e’) as a prognostic indicator in patients admitted with ST-elevation myocardial infarction (STEMI) with or without revascularization therapy to predict in-hospital mortality. BACKGROUND: Myocardial infarction is a high-risk condition, especially when filling pressure is raised, and earlier reports have suggested that E/e’ is associated with poor outcome. However, whether E/e’ predicts risk better than left ventricular ejection fraction (LVEF), which is the current standard of practice, is not known. MATERIALS AND METHODS AND RESULTS: The echocardiographic evaluation of mitral inflow E wave velocity-to-tissue Doppler e’ wave velocity ratio (E/e’) as a prognostic indicator in ST-elevation myocardial infarction” was carried out on 100 patients admitted in the Department of Cardiology of Fortis Escorts Heart Institute, Okhla, New Delhi, from November 2019 to March 2021. The mean age of the patients with ST-elevation myocardial infarction was 59.8 ± 11.3 years. In patients who had E/e’ >15, male predominance and higher age (mean 63.7 ± 7.7 years) were found. Out of common cardiovascular risk factors, smoking and diabetes mellitus were found to be statistically significant. 67.7% of patients were belonged to the Killip Class II or more. In patients who had E/e’ >15, 29 (93.5%) patients had LVEF ≤45%. Twenty-seven (87.1%) patients had deceleration time (DT) ≤140 ms. Moderate or severe mitral regurgitation (MR) was found in 19.4% of patients, while the mean values of LVEDD and LVESD were 50.4 ± 2.15 mm and 39.7 ± 3.3 mm, respectively. The mean velocity of E and A was 0.87 ± 0.12 m/s and 0.75 ± 0.11 m/s, respectively. The mean E/A ratio was 1.1 ± 0.22. The mean velocity of e’ was 5.02 ± 0.45 cm/s and E/e’ ratio was 17.48 ± 1.57. The association of various clinical features showed that male gender, higher age, smoking, and diabetes mellitus, cardiogenic shock, and Killip Class II or greater were significant factors associated with E/e’ >15. Echocardiographic findings showed that LVEF ≤45%, higher LVEDD and LVESD, higher peak E velocity, DT ≤140 ms, lower mitral annulus e’ velocity, higher E/e’ ratio, and moderate or severe MR were significantly associated with E/e’ >15. CONCLUSION: The current study concluded that Doppler echocardiographic estimation of E/e’ ratio can be used as a marker of elevated left ventricular filling pressure and hence can be used as a prognostic marker in risk stratification of patients admitted in coronary care units. The E/e’ ratio is an independent and powerful predictor of the in-hospital mortality.