Prognostic Information from On-Line Vectorcardiography in Unstable Angina Pectoris

Abstract

The prognostic information from 24-hour monitoring with on-line vectorcardiography (VCG) was assessed in 100 patients with a clinical diagnosis of unstable angina pectoris. ST change vector magnitude, ST vector magnitude and QRS vector difference were monitored. During a follow-up period of 343 ± 77 days, 7 patients died from cardiac causes and 8 patients had a nonfatal myocardial infarction (MI). Thirty patients were readmitted for unstable angina pectoris and 36 were revascularized because of medical refractory angina. Univariate predictors of cardiac death or nonfatal MI included greater age, rest pain during hospitalization, previous MI, diabetes mellitus and high incidence of supposedly ischemic transient ST and QRS vector changes. In multivariate analysis, a high incidence of transient ST (p < 0.01) and QRS (p < 0.01) vector changes provided additional prognostic information beyond that of clinical and exercise test data. In conclusion, VCG monitoring during the first 24 h of hospitalization for unstable angina pectoris identifies patients with increased risk of adverse cardiac events.

Prognostic Value of Ischemia Monitoring with On-Line Vectorcardiography in Patients with Unstable Coronary Artery Disease

“…Our results add to previous evidence regarding the prognostic information of ST-VM and STC-VM measurements [6, 9, 18]. In contrast to most other measurements, VCG monitoring is useful for early risk stratification.…”

“…Conflicting data are present regarding the prognostic information of QRS-VD [6, 8]. However, we found a clear trend of maximum QRS-VD to be related to the risk of death.…”

“…Therefore, early risk stratification is critical. Several studies have indicated that continuous on-line vectorcardiography (VCG) gives prognostic information both in patients with unstable angina [6]and those with acute MI [7]. However, these findings need to be tested in independent patient populations.…”

Detection of Myocardial Ischemia With a Computer-Assisted 12-lead 24-hour ECG Monitoring System (EAGLE) in Patients With Suspected Unstable Angina

“…The ECG waveform is a real-time waveform, and artifact cannot be avoided. The 24-h recording of 3 Frank leads and the mathematical reconstruction of the standard 12-lead ECG from the Frank leads has been reported recently; 29,30 however, the clinical significance of this has not been validated yet.…”

A Technical Approach for Optimizing Surveillance of Patients with Unstable Coronary Syndromes: Continuous Vectorcardiography Ischemic Monitoring

“…More objective techniques for risk assessment of patients have been proposed during the last decades as a supplement to the medical history and examination. These include methods that assess the electrical consequences of UCS, i.e., 12-lead electrocardiogram (ECG) [3, 4], predischarge exercise ECG testing [5, 6], and continuous QRS and S-T segment monitoring [7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28]; analyses that assess the myocardial damage, i.e., myocardial biochemical markers, e.g., the troponins [6, 19, 27, 29], and tests that assess the contractile function, i.e., stress echocardiography [30], and myocardial blood flow, i.e., sestamibi SPECT scintigraphy [31]. The method of continuous vectorcardiography ischemic (QRS and S-T segment) monitoring (VCG) is increasingly used in this respect.…”