非房颤患者的房颤诱发率：正常意味着什么？

Background: While inducibility of atrial fibrillation (AF) is often used as an endpoint for radiofrequency ablation of AF little is known regarding inducibility among normals  We therefore evaluated the inducibility of AF with rapid atrial pacing in patients without a clinical history of AF after catheter ablation of supraventricular tachycardia (SVT)  Methods: We prospectively evaluated 86 patients with no history of AF who were referred for catheter ablation of SVT  After successful ablation two different rapid atrial pacing protocols for induction of AF were tested  First AF induction was attempted by 5second bursts of atrial pacing from the coronary sinus ostium (CSO) at three different cycle lengths (CLs)  Next decremental pacing was performed from the CSO starting at a CL of 250 ms to the loss of 1:1 atrial capture  This protocol was repeated 3 times for each subject  Results: Three of the subjects (3 5%) enrolled had inducible AF with the first pacing protocol  However with the second protocol AF was inducible in 22 patients (25 6%) including sustained AF in 16 patients (18 6%)  There were significant differences in the inducibility of AF between the two atrial pacing protocols  Additionally with the second pacing protocol patients with a loss of 1:1 atrial capture at CL <180 ms were more easily inducible for AF (21/63 vs  1/23,  P =  006)  Conclusion: Using a specific decremental pacing protocol 26% of patients without a history of AF had inducible AF  These findings suggest that significant further investigation is needed to optimize the specificity of using AF induction as an endpoint for AF ablation  © 2011 Heart Rhythm Society