Recommendation for Inclusion of Surface Echocardiography in Evaluation of Chest Pain in Acute Emergency Care

Abstract

Objective  A significant number of conditions may mimic acute myocardial infarction when patients present to acute emergency care (AEC) with chest pain. A proportion of such patients may exhibit ST segment abnormality on the electrocardiogram (ECG) which is due to conditions other than acute coronary syndromes (ACS) or myocardial infarction. The American Heart Association/American College of Cardiology guidelines (2015) algorithm for ACS does not include echocardiographic evaluation in the assessment of chest pain. Patients with chest pain may be subjected to investigations and interventions based on ECG leading unwarranted invasive procedures, which may prove unnecessary, futile, and even detrimental. This study was performed to determine if a bedside echocardiography would help identify the conditions that do not need intervention and might possibly change the treatment pathway at the right time. Materials and Methods In a prospective observational study design, adult patients presenting to AEC with chest pain were included in the study. After the assessment of airway, breathing and circulation, and initiation of bed side monitoring, a 12-lead ECG was obtained. Patients exhibiting a significant ST change on ECG were subjected to bedside echocardiography, that is, two-dimensional (2D) transthoracic echocardiography (2D-TTE) with a cross reference to a consultant cardiologist for the precise assessment and diagnosis. The findings of echocardiography were correlated with electrocardiogram for possible diagnostic coronary angiography and percutaneous coronary intervention. The results of ECG, echocardiography, and coronary angiography (if done) were analyzed to determine the sensitivity and specificity of echocardiography for ACS. Results Among 385 patients in the study, 312 were suspected to suffer acute coronary syndrome; among these patients, eight patients turned out to have chest pain due to non-ACS. Of the 73 patients, the chest pain was suspected to be not of cardiac ischemia origin; among these patients, 66 patients were true negative and 7 patients were false positive. Echocardiography was the predictive of ischemic chest pain with a predictive value of 97.7%. The specificity of echocardiography calculated from the above confusion matrix was 90.4% and sensitivity was 97.4%. The positive predictive value of 2D-TTE was 97.7% and negative predictive value was 89.1%. The overall accuracy of bedside 2D-TTE was 96.1%. Conclusion Echocardiography was found to be an effective tool in aiding diagnosis of a patient presenting to AEC with chest pain and ST-T changes in ECG. A significant percentage of patients (18.7%) presented to AEC with chest pain, ST-T changes and found to have causes other than ACS, and screening echocardiography (2D-TTE) was able to identify 90.4% of those cases. From this study, we conclude that bedside echocardiography had high specificity (90.4%) and sensitivity (97.43%) in identifying regional wall motion abnormality due to ACS. Hence, bedside echocardiography is recommended in patients with chest pain and ST-segment abnormality to avoid unnecessary delay in diagnosis and invasive interventions in non-ACS