The clinical application of sinus node function test by transvenous atrial pacing

106 patients,including NON-SSS group 62 cases and SSS group 44 cases,were subjected tosinus node function test by transvenous atrial pacing in recent 3 years.
The criteria for sinus dysfunction were:SNRT≥1400ms and/or AV junctional escape beforesinus recovery and/or secondary pause,SNRTc≥560ms,total SACT≥300ms.
In the detection of SSS,SNRT was most sensitive with 88.7% positive rate in SSS group and9.6% false positive rate in NON-SSS group.The positive rate of SNRTc,total SACT in the SSSgroup were 76.8% and 44%,and false positive rate inthe NON-SSS group 1.6% and 3.3% re-spectively.However,with any one abnormal parameter considered as sinus node dysfunction,thepositive rate was 100% in the SSS group while false positive rate in the NON-SSS group was15%.AV junctional escape before sinus recovery and secondary pause were only found in SSS pa-tients.So it seemed that positive result of any these parameters was significant in the diagnosisof SSS if false positive result could be excluded.