The Relationship of ST Segment Changes in Lead aVR with Outcomes after Myocardial Infarction; a Cross Sectional Study
Journal Title: Archives of Academic Emergency Medicine - Year 2017, Vol 5, Issue 1
Abstract
Introduction: Among the 12 leads studied in electrocardiography (ECG), lead aVR can be considered as the most forgotten part of it since no attention is paid to it as the mirror image of other leads. Therefore, the present study has been designed with the aim of evaluating the prevalence of ST segment changes in lead aVR and its relationship with the outcome of these patients. Methods: In this retrospective cross sectional study medical profiles of patients who had presented to emergency department with the final diagnosis of myocardial infarction (MI) in a 4-year period were evaluated regarding changes of ST segment in lead aVR and its relationship with in-hospital mortality, the number of vessels involved, infarct location and cardiac ejection fraction. Results: 288 patients with the mean age of 59.00 ± 13.14 (18 – 91) were evaluated (79.2% male). 168 (58.3%) patients had the mentioned changes (79.2% male). There was no significant relationship between presence of ST changes in lead aVR with infarct location (p = 0.976), number of vessels involved (p = 0.269) and ejection fraction on admission (p = 0.801). However, ST elevation ≥ 1 mv in lead aVR had a significant relationship with mortality (Odds = 7.72, 95% CI: 3.07 – 19.42, p < 0.001). Sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios of ST elevation ≥ 1 for prediction of in-hospital mortality were 41.66 (95% CI: 22.79 – 63.05), 91.53 (95% CI: 87.29 – 94.50), 31.25 (95% CI: 16.74 – 50.13), 94.44 (95% CI: 90.65 – 96.81), 0.45 (95% CI: 0.25 – 0.79), and 0.05 (95% CI: 0.03 – 0.09), respectively. Conclusion: Based on the results of the present study, the prevalence of ST segment changes in lead aVR was estimated to be 58.3%. There was no significant relationship between these changes and the number of vessels involved in angiography, infarct location and cardiac ejection fraction. However, presence of ST elevation ≥ 1 in lead aVR was associated with 8 times increase in in-hospital mortality risk.
Authors and Affiliations
Keywords
Related Articles
- EP ID EP339321
- DOI 10.22037/emergency.v5i1.17655
- Views 188
- Downloads 0
Continuous Education of Basic Life Support (BLS) through Social Media; a Quasi-Experimental Study
Introduction: It is imperative, if not fundamental, for medical students to receive continuing education in Basic life support (BLS). This present study aimed to investigate the effectiveness of continuing education usin...
Acute Myocardial Infarction following Naltrexone Consumption; a Case Report
Cardiovascular effects of opioid withdrawal have long been studied. It was reported that patients with underlying ischemic heart disease and atherosclerotic vessels may be complicated by a sudden physical and emotional s...
Screening Characteristics of TIMI Score in Predicting Acute Coronary Syndrome Outcome; a Diagnostic Accuracy Study
Introduction: In cases with potential diagnosis of ischemic chest pain, screening high risk patients for adverse outcomes would be very helpful. The present study was designed aiming to determine the diagnostic accuracy...
A Cross-sectional Study on Epidemiology and Death-Related Factors of Oncology Patients in Emergency Department
Introduction: Accurate diagnosis and proper treatment of oncology patients presented to emergency department (ED) can dramatically enhance their quality of life and decrease their mortality rate. Therefore, the present s...
Evidence Based Emergency Medicine Part 3: Positive and Negative Likelihood Ratios of Diagnostic Tests
In the previous two parts of educational manuscript series in Emergency, we explained some screening characteris-tics of diagnostic tests including accuracy, sensitivity, specificity, and positive and negative predictive...