Dynamic on-line vectorcardiography improves and simplifies in-hospital ischemi monitoring of patients with unstable angin

Objectives. This study sought to validate computerized vector-cardiography against the established technique of Holter electro-cardiographic (ECG) monitoring and to compare the feasibility of the two methods for monitoring patients with unstable angin pectoris. Background. Detection of myocardial ischemic episodes is an important objective in patients admitted to the hospital for unstable angin pectoris. Standard ECG monitoring may be sufficient for detection of symptomatic episodes but will often overlook silent ischemia. Holler ECG monitoring has higher likelihood of discovering such episodes, but analysis is time-consuming, and the results are not available on-line. Methods. We simultaneously monitored 53 consecutive patients with unstable angina, 46 of whom had technically adequate 24-h Holter ECGs and computerized vectorcardiograms. Results. The Holter tapes had mean (±SD) of 15.3 ± 10.3 h of recording with both channels technically adequate for analysis compared with 23.7 ± 1.77 h of vectorcardiographic recording that could be analyzed (p < 0.01). Of the 15 symptomatic episodes detected by Holter ECG monitoring, 13 were also detected with dynamic vectorcardiography. In contrast, eight patients had 18 episodes of chest pain, with simultaneous ST segment changes detected by dynamic vectorcardiography; only 9 of these episodes were also detected by Hotter ECG monitoring. Conclusions. Monitoring of myocardial ischemi with dynamic vectorcardiography seems to be more efficient than Holter monitoring and may have higher sensitivity. Computerized, continuous vectorcardiography has complete real-time capacity, allowing monitoring over prolonged periods of time, and the results are immediately available without time-consuming analysis.