High degree atrioventricular (AV) block is manifested in low incidence (2,1%) during postoperative heart surgery and could be transient or permanent. In the absence of block reversibility criterions. permanent pacemaker (PPM) implantation is recommended when AV block is persistent longer than 15 days. In isolated cases the block could be reversible after this period. Av block occurred in 4 of 300 patients who underwent cardiac surgery. We reviewed their records and confirmed that neither the heart rate nor compared QRS characteristics in the periods before, during or after block, is usefully to predict block reversibility. The intracardiac electrophysiologic study is unnecessary to indication of PPM. Corrected pacemaker recovery time greater than 2 seconds indicates junctional or idioventricular activity uncertain and should be investigated as block reversibility criterion.
