Abstract
This is a report of two sick sinus syndromes succesfully treated with the implantation of transvenous pacemaker. In case I, this was a 49-years-old housewife who had a few syncopal attacks and was manifested sinoatrial block with partly sinus arrest on electro-cardiograms. In case II, this was a 63-years-old man who showed sinus bradycardia, left axis deviation and complete right bundle branch block with partly sinoatrial block and several atrial arrhythmias. On cardiac evaluation of case II, the sinus node recovery time (SRT) was markedly prolonged after overdrive with atrial pacing at 120 beats/min, for one minute (SRT=5528msec. ).
The treatment for such case with syncopal attacks or possibility of this was described. At admission, intracardiac evaluations, such as His bundle electrograms and measurement of SRT with means of overdrive suppression, were performed, Then transvenous temporary pacing was started. Under temporary pacing, several drugs were administered and that effects were evaluated.
At the present, we considered the indications of pacemaker implantation on sick sinus syndromes; (1) no effective therapy, but pacing, (2) apparent Stokes-Adams syndrome or syncopal attacks from unknown origin, (3) in EKG, widespread abnormalities of impulse formation and conduction, (4) BTS, (5) important complications as congestive heart failure, or angina pectoris, and (6) prolonged SRT.
