Electrocardiographic Changes and Coronary Findings in Patients with Acute non-ST-Elevation Myocardial Infarction: A Cross-Sectional Study

Abstract

Background: Despite significant improvements in diagnosis and treatment, non-ST-Elevation Myocardial Infarction (NSTEMI) is still one of the health problems in developed and developing countries. Objectives: The present study was performed to assess the electrocardiographic changes and coronary findings in patients with NSTEMI. Methods: The study enrolled 158 patients with NSTEMI diagnosis at the discharge time. Demographic characteristics and electrocardiographic changes were collected using a checklist from the medical records of the patients. The angiography data were used to calculate a syntax score for each patient. Finally, patients were divided into three groups based on this score: high risk >32, intermediate risk 22-32, and low risk < 22. Involved vessels, including the left anterior descending artery, Right Coronary Artery (RCA), Left Circumflex Artery (LCX), and the left main stem, were also determined. Results: The mean age of the patients was 60.68 ± 12.15 years. The LAD, LCX, and RCA were the most common involved vessels, in sequence. About 27.73, 67.15, and 5.12% of the patients were assigned to low, moderate, and high-risk groups, respectively. Statistically significant differences were observed in the frequencies of ECG changes (P = 0.003) and types of involved vessels (P < 0.001) between low, moderate, and high-risk patients. In addition, there were statistically significant differences in the mean syntax scores between different types of involved vessels (P < 0.001). Conclusions: The findings of the present study showed a significant relationship between the types of vessel involvement and syntax score. Also, there was a high prevalence of ST changes in precordial leads that may improve the sensitivity of diagnosis. We did not find any significant relationship between the frequencies of ECG changes based on the types of involved vessels.