Diagnosis of acute myocardial infarction in patients with chronic right bundle-branch block using standard 12-lead electrocardiogram compared with dynamic vector cardiography.

The aim of the study was to evaluate standard 12-lead electrocardiogram (ECG) criteria and to compare them with dynamic vector cardiography in patients with chronic right bundle-branch block for diagnosing acute myocardial infarction. We used standard 12-lead ECGs recorded on admission and after 12-24 h and compared them with dynamic vector cardiography with trend analysis during the first 12 h. In patients with right bundle-branch block, ST segment changes occurred in the same way as for patients with narrow QRS complexes. By adding 4 h of continuous vector cardiographic monitoring we were able to identify patients with acute myocardial infarction with a high diagnostic accuracy.