J Korean Soc Emerg Med.  2000 Dec;11(4):530-538.

The Eletrocardiographic Analysis of Acute Myocardial Infarction and Non-infarction Syndrome In the Patients with ST Segment Elevation and Chest Pain

• Ryoo JH
• Kim YK
• So JI
• Heo T
• Min YI

Abstract

BACKGROUND: ST segment elevation in patient with chest pain was seen in acute myocardial infarction and in numerous other non-infarction syndrome. The causes of non-infarction syndrome were left ventricular hypertrophy, BER(benign early repolarization), and left bundle branch block in cardiac origin and were hyperkalemia and hyperventilation syndrome in metabolic origin and were others. Furthermore, the differentiation of electrocardiogram between acute myocardial infarction and non-infarction syndrome was very difficult. So, we compared and analysed characteristics of ST segment elevation of acute myocardial infarction and non-infarction syndrome that suggested the clue of early diagnosis of coronary artery disease. METHOD AND MATERIALS: We retrospectively reviewed the electrocardiogram of 961 patients with chest pain who visited the emergency center from January 1999 to December 1999. Acute myocardial infarction was diagnosed by clinical finding, electrocardiogram, cardiac enzyme, echocardiogram, and myocardial spect. Left ventricular hypertrophy, BER, and left bundle branch block in cardiac origin of non-infarction syndrome were diagnosed by electrocardiographic criteria suggested by William J. Brady. Acute myocarditis, acute pericarditis, and hyperventilation syndrome were diagnosed by clinical finding.
RESULTS
Among 961 patients with chest pain, 236(24.6%) patients manifested ST segment elevation who were diagnosed acute myocardial infarction in 162(68.6%) patients and non-infarction syndrome in 74(31.4%) patients. The causes of non-infarction syndrome in 74 patients were left ventricular hypertrophy(32:13.6%), BER(28:11.9%), left bundle branch block(11:4.7%), and others(3:1.3%). Three others were acute myocarditis, acute pericarditis, and hyperventilation syndrome. Electrocardiographic characteristics of ST segment elevation of non-infarction syndrome manifested almost same finding compared to William J. Brady' criteria.
CONCLUSION
ST segment elevation in patient with chest with chest pain visited emergency department was seen in acute myocardial infarction(68.6%) and the other non-infarction syndromes(31.4%). Significant number of patients were not associated with acute myocardial infarction. Therefore, we must completely understand characteristics of ST segment elevation in acute myocardial infarction and the other non-infarction syndromes to diagnose fatal early coronary artery disease and to avoid unnecessary thrombolytic therapy.

MeSH Terms

Bundle-Branch Block
Chest Pain*
Coronary Artery Disease
Early Diagnosis
Electrocardiography
Emergencies
Emergency Service, Hospital
Humans
Hyperkalemia
Hypertrophy, Left Ventricular
Hyperventilation
Myocardial Infarction*
Myocarditis
Pericarditis
Retrospective Studies
Thorax*
Thrombolytic Therapy
Tomography, Emission-Computed, Single-Photon