CLINICAL-APPLICATION OF A MICROCOMPUTER SYSTEM FOR ANALYSIS OF MONOPHASIC ACTION-POTENTIALS

Computerized analysis of monophasic action potentials (MAPs) has rarel y been reported in clinical setting We developed a computer system fea turing on-line acquisition and user-monitored automatic measurement of multichannel MAPs with the capability of manual corrections. This sys tem has been used in 34 patients in whom two-channel MAPs and 1-lead E CG were digitized during sinus rhythm, pacing, and programmed stimulat ion (PS). In total, 41,413 MAPs in 212 data files were measured. The c orrect determination rate was 100% for MAP onset and plateau, 99.78% ( 95.76% during PS) for MAP baseline, and 99.96% (54.24% during PS) for QRS onset. The comparison between the computerized and manual measurem ents in 292 MAPs showed that the former highly agreed with the latter, with the limits of agreement, defined as mean difference +/- 2 SD, be ing from - 4.8-4.9 ms for activation time and from - 4.2-6.0 ms for MA P duration measurements. Using this system, two-channel MAPs of more t han 300 consecutive beats can be measured in a few minutes, which made if possible to determine the steady state of MAP duration individuall y, and evaluate the MAP changes during intervention in detail. The cli nical routine procedure for testing the effective refractory period an d several new MAP parameters were also evaluated using this system. Co nclusion: The MAP measurement using this computer system is reliable, rapid and accurate; it can therefore replace the manual method and pro vide more useful information for clinical research.