Korean Circ J.  1985 Jun;15(2):255-268. 10.4070/kcj.1985.15.2.255.

Clinical Cardiac Electrophysiological Study on the Sinus Node and Atrioventricular Conduction System

• Choi YS
• Lee MM
• Park YB
• Seo JD
• Lee YW

• KMID: 2229623
• DOI: http://doi.org/10.4070/kcj.1985.15.2.255

Abstract

Clinical EPS was performed in 16 normal adults without evidence of conduction disease on the surface standard 12 lead electrocardiogram in order to provide normal electrophysiological values of the sinus node function and AV conduction. EPS was also performed in 15 patients with sick sinus syndrome and 10 patients with AV conduction disturbance to evaluate the clinical usefulness of EPS in detecting sinus node dysfunction and AV conduction disturbance. The results were as follows. 1) The results of sinus node function test in the normal group were m-SNRT 853+/-198msec(range 800-1,560msec), c-SNRT 230+/-66msec(range 120-370msec), and %m -SNRT/SCL 127+/-11%(range 114-149%). 2) In 15 patients with SSS, the M-SNRT were ranged from 1,270 to 12,330msec and 10 patients(66%) had significantly increased m-SNRT exceeding 1,560msec. The c-SNRT were ranged from 230 to 10,730msec and 13 patients(83%) had significantly increased c-SNRT exceeding 370msec. The % m-SNRT/SCL were ranged from 136 to 770% and 12 patients(80%) had significantly increased % m-SNRT/SCL exceeding 150%. 3) The SACT in normal group were 84+/-14msec(range 70-105msec) measured by continuous atrial pacing method and 80+/-19 msec(range 60-115msec) measured by atrial extrastimulation method. 4) In SSS, the SACT measured by continuous atrial pacing method was ranged from 80 to 1,050msec and 11/12 patients(92%) had significantly increased SACT exceeding 112 msec. The SACT measured by atrial extrastimulation method was ranged from 90 to 310msec and 7/8 patients(88%) had significantly increased SACT exceeding 118 msec. 5) C-SNRT, % m-SNRT/SCL, and SACT were more useful in detecting sinus node dysfunction than m-SNRT. 6) The AV conduction intervals in normal group were PA interval 17+/-6(range 5-25msec), AH interval 96+/-18 msec(range 70-135msec), and HV interval 46+/-7msec(range 35-55msec). 7) Rapid atrial pacing induced Wenckebach type second degree AV block proximal to H at pacing rate of 90 to 190/min in 14/16 normal adults. 2 patients maintained intact AV conduction upto maximum pacing rate of 200/min. 8) His bundle electrogram showed the site of AV block in 9 of 10 patients with AV conduction disturbances. The sites of AV block were AV nodal area 1 case, intraHis bundle 4 cases, and infraHis bundle 4 cases. 9) EPS provided a good supportive information that was useful in selecting pacemaker therapy in a patient with chronic bifascicular block who revealed prolonged HV interval and infraHis bundle block at a pacing rate of 70min. 10) The refractory periods of AV conduction system in normal group were AERP 274+/-54msec (range 170-410msec), AVN-FRp 467+/-74msec(range 285-600msec), AVN-ERP 341+76msec(range 190-460), and V-ERP 280+/-25msec(range 240-320msec).

MeSH Terms

Adult
Atrioventricular Block
Electrocardiography
Electrophysiologic Techniques, Cardiac
Humans
Sick Sinus Syndrome
Sinoatrial Node*