[Diagnosis of stress-induced myocardial ischemia: accuracy of a direct recording long-term ECG system in comparison to standard ECG equipment].
The accuracy of ST-segment analysis with a direct-recording long-term ECG system (CardioData Mk 4) with a good low-frequency response was compared to that obtained by a standard ECG-recorder. Twenty-two patients with coronary heart disease and a positive exercise test were submitted to a second bicycle exercise test with concomitant long-term ECG registration. Application of a special switch device made it possible to record not only extremity and chest leads but also the two bipolar long-term ECG leads simultaneously on both the standard-ECG (leads ECG 1 and 2), and the long-term ECG (leads LEG 1 and 2). We determined the time of the beginning, end, maximum, and the magnitude of the ST-segment depression in bipolar leads LEG 1/2 and ECG 1/2, as well as in the unipolar leads V5/V6 of the exercise ECG. The long-term ECG was just as accurate as the standard ECG: the time intervals between the different leads showed good agreement. The degree of maximum ST-segment depression in ECG 1 (MW +/- SD = 2.2 +/- 1.1 mm) was identical to that in LEG 1 (2.2 +/- 1.3 mm). The maximum extent of ST-segment depression was lower in ECG 2 and LEG 2 but also comparable (ECG 2: 1.4 +/- 1.4 mm, LEG 2: 1.5 +/- 1.7 mm). Comparison of the unipolar leads V5/V6 of standard ECG with the bipolar lead LEG 1 of the long-term ECG yielded nearly identical results: V5/V6 2.0 +/- 0.7 mm; LEG 1: 2.2 +/- 1.3 mm.(ABSTRACT TRUNCATED AT 250 WORDS)
Andresen
D
D
Medizinische Klinik und Poliklinik der Freien Universität Berlin.
Brüggemann
T
T
Jereczek
M
M
Schröder
R
R
D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis; D003327:Coronary Disease / Q000175:diagnosis*; D004562:Electrocardiography / Q000295:instrumentation*; D005080:Exercise Test / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation; D012815:Signal Processing, Computer-Assisted
Diagnostik belastungsinduzierter Myokardischämien: Analysegenauigkeit eines direktaufzeichnenden Langzeit-EKG-Systems im Vergleich zu einem Standard-EKG-Gerät.