The direct detection of sinus nodal potentials in man by means of the signal-averaging technique
Hombach, V.; Scholl, H.; Braun, V.; Gil-Sanchez, D.; Behrenbeck, D.W.; Tauchert, M.; Hilger, H.H.
Zeitschrift für Kardiologie 68(10): 720-723
1979
ISSN/ISBN: 0300-5860 PMID: 516847 Document Number: 146643
In 13 patients in the age range of 34 to 70 years (mean: 53 +/- 10 years), during diagnostic His-bundle investigations, registrations from the sinus nodal area were analyzed with a signal-averaging computer. In 12 patients we were able to get reproducible per-P-potentials with a sino-atrial conduction interval between 56 and 227 ms. The normal sequence of the excitation process from the atrium to the AV node together with the bundle of His and to the ventricles in all patients, and the reproducibility of the signal-averaged pre-P-potentials, which were well outlined from the atrial potential with a reasonable conduction interval, suggest that these signal-averaged pre-P-potentials reflect the sinus nodal activity rather than an ectopic focus. In 5 of 11 comparable cases there was a good correlation between the signal-averaged sino-atrial conduction intervals and those calculated with the extrastimulus technique. In 2 patients this correlation was moderate. The signal-averaging process may be impaired by coarse random noise, frequent atrial or ventricular extrasystoles, and by fluctuations of the baseline of the sinus nodal lead. The fact that the registrations are performed during normal undisturbed sinus rhythm offers a considerable advantage over the extrastimulus technique.