Continuous recording of direct arterial pressure and electrocardiogram in unrestricted man

A system has been devised which records direct arterial pressure, electrocardiogram, and other variables in man with no restriction of activity. The advantage of this system is that the record is on magnetic tape, and it is possible to replay the records at various speeds to analyse each beat or to produce an entire 24-hour record on a few feet of paper. A marker allows the timing of relevant events. Initial experience with this procedure indicates that is is safe and reliable.