M. Dellborg et al., DYNAMIC ONLINE VECTORCARDIOGRAPHY IMPROVES AND SIMPLIFIES IN-HOSPITALISCHEMIA MONITORING OF PATIENTS WITH UNSTABLE ANGINA, Journal of the American College of Cardiology, 26(6), 1995, pp. 1501-1507
Objectives. This study sought to validate computerized vectorcardiogra
phy against the established technique of Holter electrocardiographic (
EGG) monitoring and to compare the feasibility of the two methods for
monitoring patients with unstable angina pectoris. Background. Detecti
on of myocardial ischemic episodes is an important objective in patien
ts admitted to the hospital for unstable angina pectoris. Standard ECG
monitoring may be sufficient for detection of symptomatic episodes bu
t will often overlook silent ischemia. Holter ECG monitoring has a hig
her likelihood of discovering such episodes, but analysis is time-cons
uming, and the results are not available on-line. Methods. We simultan
eously monitored 53 consecutive patients with unstable angina, 46 of w
hom had technically adequate 24-h Holter ECGs and computerized vectorc
ardiograms. Results. The Holter tapes had a mean (+/-SD) of 15.3 +/- 1
0.3 h of recording with both channels technically adequate for analysi
s 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 vectorcar
diography. In contrast, eight patients had 18 episodes of chest pain,
with simultaneous ST segment changes detected by dynamic vectorcardiog
raphy; only 9 of these episodes were also detected by Holter ECG monit
oring. Conclusions. Monitoring of myocardial ischemia with dynamic vec
torcardiography seems to be more efficient than Holter monitoring and
may have a higher sensitivity. Computerized, continuous vectorcardiogr
aphy has a complete real-time capacity, allowing monitoring over prolo
nged periods of time, and the results are immediately available withou
t time-consuming analysis.