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P WAVE CHARACTERISTICS BEFORE AND AFTER TRANSCA THETER CLOSURE OF SECUNDUM
ATRIAL SE PTAL DEFECT Yip WCL1,2,
Ho TF1, Chan KY2, Quek SC1 1 National University of
Singapore, Singapore 2 Gleneagles Medical
Center, Singapore Objective: P maximum (pm) and p
dispersion (pd) have been used as predictors of atrial dysrhythmias in
adults The aim of this study was to assess these parameters before and
after transcatheter closure of atrial septal defects (ASD). Methods: Twenty-three patients(9
males and 14 females; mean±SD age at procedure:14.2±16.3years)with isolated ASD who had undergone transcatheter device
closure(20 Amplatzer septal occluders,3 Starflex occluders)and 22 age-and
sex-matched controls were studied Resting 12-lead ECG was used to measure p
waves from which pm and pd(difference between maximum and minimum p wave
duration)were derived. Results: Patients had
significantly longer mean pm(10.8±10.6vs93.3±10.8msec,p<0.0001)and pd(39.7±11.7vs26.1±6.2msec, p<0.0001). Significant reduction of mean pm to 99.5±10.9 msec and mean pd to 31.1±8.7msec were observed within the first 7 days
post-closure as compared to the pre-closure values Mean pm and pd remained
closely similar with marginal decrease in pd over 3 years post-closure
follow-up. Conclusion: Prolonged
atrial conduction time and inhomogeneity of atrial conduction in patients
with ASD were favourably altered by transcatheter closure of the defects.