Comparison of different methods of ST measurementfor evaluation of myocardial ischaemia in Holter monitoring

Abstract

Long-term ambulatory electrocardiographic monitoring [AEM] of the ST segment is clinically the most practical test for the documentation and quantification of myocardial ischaemia. However, there is still some controversy about the validity of ST measurements in Holter monitoring. Therefore, in the present study, in a series of 26 patients with angiographically proven (greater than 70%) coronary heart disease and a positive exercise electrocardiogram, the number, duration and the severity of symptomatic and asymptomatic ischaemic episodes were measured by (1) the ST change at the J point, (2) the ST change 0.07-0.10 s after the J point (immediately before the T wave), (3) the change of the slope of the ST segment, and (4) the area under the ST segment, with a Reynolds Pathfinder III and compared with visual analysis. At the J point (1) there were a total of 264 episodes with a duration of 3947 min and a maximum of 0.35 mV, before the T wave (2) 276 episodes with a duration of 3440 min and a maximal change of 0.40 mV; looking at the slope of the ST segment (3) the figures were 118, 1041 min and regarding the area under the ST segment they were 198, 2385 min. In conclusion, ST deviations are safely detected by automated analysis of the ST segment. Compared with visual analysis (220 episodes), deviation of the ST1 (J point) and ST2 point (80 ms thereafter) overestimate the incidence of true ischaemic ST depression by about 20%.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of 24-Hour Ambulatory Electrocardiographic Recording in Detecting Asymptomatic Coronary Artery Disease in Diabetic Subjects

“…One explanation for the low sensitivity of 24-hour recording is also the use of only 2 modified bipolar leads to detect ST segment depressions com pared to 12 leads during exercise electrocardiography. Furthermore, the high-speed analyzing system and prob lems related to the proper adjustment of measurement points [ 17] may also influence the sensitivity of 24-hour ECG recording to detect ischemia. The real-time analyz ing systems may give some advantages in this respect.…”