Hypertens. 2006;8:12-18)

Background— Adenosine can unmask dormant pulmonary vein (PV) conduction after PV isolation. Adenosine can also induce ectopy in electrically silent PVs after isolation, possibly via activation of autonomic triggers. We sought to identify the implications of adenosine-induced PV ectopy for atrial fibrillation (AF) recurrence after PV isolation. Methods and Results— A total of 152 patients (age, 60±11 years; 63% paroxysmal AF) undergoing PV isolation for AF were studied. After each PV was isolated, adenosine was administered and the presence of adenosine-induced PV reconnection and PV ectopy were recorded. Dormant conduction was targeted with additional ablation. Adenosine-induced PV ectopy was seen in 45 (30%) patients, and dormant conduction was seen in 44 (29%) patients. After a median follow-up of 374 days, 48 (32%) patients had recurrent AF after a single ablation procedure. Rates of freedom from AF among patients with adenosine-induced PV ectopy were significantly lower than patients without adenosine-induced PV ectopy (63% versus 76% at 1 year; log rank, 0.014). Rates of freedom from AF among patients with dormant conduction were also lower than patients without dormant conduction (64% versus 76% at 1 year; log rank, 0.062). With multivariate analysis, adenosine-induced PV ectopy was found to be the only independent predictor of AF after PV isolation (hazard ratio, 1.90; 95% confidence interval, 1.06–3.40; P =0.032). Conclusions— Adenosine-induced PV ectopy is a predictor of recurrent AF after PV isolation and may be a marker of increased susceptibility to autonomic triggers of AF.

No abstract

ECG LVH using CP criteria may enhance risk stratification in high-risk patients with ICM.

TWA and ST depression testing are strong predictors of mortality among ICM patients without CP LVH, with normal testing conversely predicting low 3-year mortality. Thus, risk assessment with TWA testing and a resting ECG can identify ICM patients at low risk who may be less likely to benefit from ICD implantation.