Background-Radiofrequency catheter ablation of atrial fibrillation (AF) guided by complex fractionated atrial electrograms has been reported to eliminate AF in a large proportion of patients. However, only a small number of patients with chronic AF have been included in previous studies. Methods and Results-In 100 patients (mean age, 57Ϯ11 years) with chronic AF, radiofrequency ablation was performed to target complex fractionated atrial electrograms at the pulmonary vein ostial and antral areas, various regions of the left atrium, and the coronary sinus until AF terminated or all identified complex fractionated atrial electrograms were eliminated. Ablation sites consisted of Ն1 pulmonary vein in 46% of patients; the left atrial septum, roof, or anterior wall in all; and the coronary sinus in 55%. During 14Ϯ7 months of follow-up after a single ablation procedure, 33% of patients were in sinus rhythm without antiarrhythmic drugs, 38% had AF, 17% had both AF and atrial flutter, 9% had persistent atrial flutter, and 3% had paroxysmal AF on antiarrhythmic drugs. A second ablation procedure was performed in 44% of patients. Pulmonary vein tachycardia was found in all patients in both previously targeted and nontargeted pulmonary veins. There were multiple macroreentrant circuits in the majority of patients with atrial flutter. At 13Ϯ7 months after the last ablation procedure, 57% of patients were in sinus rhythm without antiarrhythmic drugs, 32% had persistent AF, 6% had paroxysmal AF, and 5% had atrial flutter. Conclusions-Modest short-term efficacy is achievable with radiofrequency ablation of chronic AF guided by complex fractionated atrial electrograms, but only after a second ablation procedure in Ͼ40% of patients. Rapid activity in the pulmonary veins and multiple macroreentrant circuits are common mechanisms of recurrent atrial arrhythmias. (Circulation.

Isoproterenol at infusion rates up to 20 microg/min has a high sensitivity (88%) and specificity (95%) for induction of AF in patients with PAF, regardless of whether the clinical subtype is vagotonic, adrenergic, or random.

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Recurrence of AF after EGA is usually due to PV tachycardias. Therefore, it may be preferable to systematically map and isolate all PVs during the first procedure. High-dose isoproterenol may be helpful to identify AF drivers.

Background Teaching practice-based learning and improvement and systems-based practice are challenging. Cardiology fellows at St John Hospital & Medical Center participate in a national registry of outpatient cardiology care. Objective We assessed the use of the registry, hypothesizing that it could serve as an effective foundation for studying ambulatory care, identifying gaps in care, and planning interventions to advance competence in practice-based learning and improvement and systems-based practice. Methods Starting in 2009, trainees prospectively entered data for ambulatory cardiac patients into the PINNACLE Registry database where compliance with 28 performance measures was calculated and reported quarterly. Fellows met with the program director individually and in groups to identify performance gaps and to develop and implement plans for quality improvement. Cardiology fellows were surveyed annually to assess this process. Results Through March 2012, the fellows had completed 2400 patient visits. Participation was feasible because it was cost neutral, with data form completion averaging 5 minutes. It was acceptable, with most fellows describing positive effects on practice-based learning and improvement without significant detriment to work flow. Performance achievement for drug therapies ranged from 69% (77 of 111) of the patients with atrial fibrillation receiving anticoagulation to 99% (486 of 489) of patients with coronary disease receiving lipid-lowering therapy. Gaps in system performance included low levels for diabetes screening (5%; 20 of 422) and lipid monitoring (10%; 58 of 573). Initial quality improvement projects addressed practice gaps with straightforward solutions. Improving system performance was more challenging. Conclusions Using a registry in cardiology trainees' outpatient practice is feasible, acceptable, and valuable. It allows for planning and studying the effects of quality improvement projects.