Adaniya H. Conduction blocks in and around preferential pathway of dog right atrium

SHI ADANIYA. Conduction blocks in and around preferential pathway of dog right atrium. Am. J. Physiol 253 (Heart Circ. Physiol. 22): H16-H24, 198X-We studied conduction prop-erties and histological findings at branching sites of the pectin-ate muscle (PM) from the crista terminalis (CT) in the dog right atrium. Propagation was faster in the longitudinal direc-tion along CT than along PM. When the rate of stimulation was increased, conduction blocks to PM occurred at a longer cycle length than those to CT in 10 of 19 cases without differences in the refractory period. There were two block sites, one at the lateral edge within CT and the other at the branching site of PM from CT. The former was dominant with normal solution and the latter with high K ’ solution. Histological studies showed no apparent differences between the two groups. CT consisted of a number of unit bundles in a longitudina