Tape Recordings of the ECG of Active Men

Abstract

The electronic and mechanical characteristics of the Holter-Avionics instruments for recording and analyzing the electrocardiogram of active men have been measured in the laboratory, and during carefully standardized 6-hour recordings of 385 active subjects. Although late model recorders have a cumulative timing error of less than 1%, the frequency response of the system is limited at both the upper and lower ends of the range, producing significant distortion of the complex. Scanning the taped data at 60 times real-time is a helpful screening procedure, but accurate analysis of records requires photographic write-out of R-R intervals with real-time scanning and analysis of all potential areas of abnormality. If records are made with subjects under constant observation and stop-watch timed, they can yield significant data on phenomena of rate, rhythm, and conduction, under a variety of circumstances and over long periods of time; but changes in the shape of the ST segment and T wave must be interpreted with great caution because of distortions produced by the recording system and by changes in position and activity.

Ventricular Arrhythmias in Hypertensive Left Ventricular Hypertrophy

“…In this study, we have attempted to control for some of these problems by including an age and sex matched control group. The prevalence of arrhythmia in the control group was of a similar order to that reported in asymptomatic individuals (194). Although spontaneous…”

Clinical Applications of Ambulatory Electrocardiography

“…[4], and a recent study by BraggRemschel et al [78] has investigated the ef fect of the frequency response characteristics of several systems on analysis of repolariza tion. Although current recommendations of the American Heart Association call for low and high frequency cutoffs at -3 dB of 0.05 and 100 Hz for standard electrocardiography [79], these criteria are not uniformly met in equipment used for ambulatory recording and playback [78].…”

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ECG variations in patients pre- and post-local anaesthesia and analgesia

“…13 An abnormal P-wave axis was noticed in six patients both on their screening visit and post-analgesia recordings. This implies that either the sinus node was in an abnormal position or that atrial depolarisation was not initiated by the sinus node.…”