The atria and ventricles beat independent of each other under the control of a separate pacemaker foci: one in the sinoatrial node and the other in the AV junction
a prolonged rest period in the upper AV junction
following retrograde conduction .
The presence of a common AV junction from the subcostal (en-face) view.
The identification of a common AV junction from the subcostal view had been the gold standard for diagnosis of AVSD in all the previous reports.
Data from previous studies show that AV junction
ablation can improve quality of life, although it does not appear to have an impact on hospitalization rates, mortality rates, or abilities on exercise function tests; quantitative findings from elderly patients are few.
overall ablation success rate of 95%: 100% for AV junction
ablation, 97% for AV node reentrant tachycardia ablation, and 93% for AP ablation and an overall recurrence rate of 6%.
Since the sinus node is the normal pacer, latent pacing sites at the AV junction or ventricular Purkinje fibers are driven to low resting potentials by the sinus node and have lower rates of normal automaticity (Abraham, 1992).
When the sinus node, AV junction, or ventricular Purkinje fibers escape to protect cardiac output, they have different intrinsic rates; but each site exhibits rhythmicity, a regular and predictable interval between beats.
Nonsurgical direct current (DC) catheter ablation of the AV junction
in patients with supraventricular tachycardia was documented in 1982.
While these results provide evidence supporting the potential expansion of indications regarding the use of CRT as a first-line treatment for all permanent AF patients who must undergo AV junction ablation, we look forward to conducting additional studies to provide further confirmation that will ultimately result in the modification of treatment guidelines.
Often referred to as "ablate and pace" therapy, AV junction ablation, which produces complete AV block to assure heart rate control and rhythm regulation, followed by implantation of a cardiac pacing device, is a routine, clinically validated treatment for patients with symptomatic, drug-refractory permanent AF.