title: Clinical significance of the pre-atrial electrical activity recorded by the catheter electrode in high right atrium.
abstract: 1) In canine experiment, the averaging of high right atrial electrical activity revealed the pre-A preceding the atrial deflection, which was proven to be a part of the electrical activity of sinus nodal region. 2) The pre-A was obtained in 114 (75%) of 153 clinical cases. 3) The mean pre-A interval was 18 +/- 4 msec in control group, and was prolonged in cases with sick sinus syndrome, ischemic heart disease and myocarditis. 4) The significant correlation existed between the pre-A interval and the SACT by Strauss' method (r = 0.80, p < 0.01). 5) The pre-A obtained by averaging technique is relatively simple, safe and reliable method, and is useful for evaluating the sino-atrial function.
mesh_terms: D000200:Action Potentials; D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D016275:Atrial Function; D006328:Cardiac Catheterization; D003327:Coronary Disease / Q000503:physiopathology; D004285:Dogs; D004566:Electrodes; D006329:Heart Conduction System / Q000502:physiology / Q000503:physiopathology; D006801:Humans; D008875:Middle Aged; D009205:Myocarditis / Q000503:physiopathology; D012804:Sick Sinus Syndrome / Q000503:physiopathology*; D012849:Sinoatrial Node / Q000502:physiology* / Q000503:physiopathology; D013997:Time Factors