Background-The pulmonary veins (PVs) and surrounding ostial areas frequently house focal triggers or reentrant circuits critical to the genesis of atrial fibrillation (AF). We developed an anatomic approach aimed at isolating each PV from the left atrium (LA) by circumferential radiofrequency (RF) lesions around their ostia. Methods and Results-We selected 26 patients with resistant AF, either paroxysmal (nϭ14) or permanent (nϭ12). A nonfluoroscopic mapping system was used to generate 3D electroanatomic LA maps and deliver RF energy. Two maps were acquired during coronary sinus and right atrial pacing to validate the lateral and septal PV lesions, respectively. Patients were followed up closely for Ն6 months. Procedures lasted 290Ϯ58 minutes, including 80Ϯ22 minutes for acquisition of all maps, and 118Ϯ16 RF pulses were deployed. Among 14 patients in AF at the beginning of the procedure, 64% had sinus rhythm restoration during ablation. PV isolation was demonstrated in 76% of 104 PVs treated by low peak-to-peak electrogram amplitude (0.08Ϯ0.02 mV) inside the circular line and by disparity in activation times (58Ϯ11 ms) across the lesion. After 9Ϯ3 months, 22 patients (85%) were AF-free, including 62% not taking and 23% taking antiarrhythmic drugs, with no difference (PϭNS) between paroxysmal and permanent AF. No thromboembolic events or PV stenoses were observed by transesophageal echocardiography. Conclusions-Radiofrequency PV isolation with electroanatomic guidance is safe and effective in either paroxysmal or permanent AF.

Background —Dual therapy with ticlopidine and aspirin has been shown to be as effective as or more effective than conventional anticoagulation in patients with an optimal result after implantation of intracoronary metallic stents. However, the safety and efficacy of antiplatelet therapy alone in an unselected population has not been evaluated. Methods —Patients were randomized to conventional anticoagulation or to treatment with antiplatelet therapy alone. Indications for stenting were classified as elective (decided before the procedure) or unplanned (to salvage failed angioplasty or to optimize the results of balloon angioplasty). After stenting, patients received aspirin and either ticlopidine or conventional anticoagulation (heparin or oral anticoagulant). The primary end point was the occurrence of bleeding or peripheral vascular complications; secondary end points were cardiac events (death, infarction, or stent occlusion) and duration of hospitalization. Results —In 13 centers, 236 patients were randomized to anticoagulation and 249 to antiplatelet therapy. Stenting was elective in 58% of patients and unplanned in 42%. Stent implantation was successfully achieved in 99% of patients. A primary end point occurred in 33 patients (13.5%) in the antiplatelet group and 48 patients (21%) in the anticoagulation group (odds ratio=0.6 [95% CI 0.36 to 0.98], P =0.03). Major cardiac-related events in electively stented patients were less common (odds ratio=0.23 [95% CI 0.05 to 0.91], P =0.01) in the antiplatelet group (3 of 123, 2.4%) than the anticoagulation group (11 of 111, 9.9%). Hospital stay was significantly shorter in the antiplatelet group (4.3±3.6 versus 6.4±3.7 days, P =0.0001). Conclusions —Antiplatelet therapy after coronary stenting significantly reduced rates of bleeding and subacute stent occlusion compared with conventional anticoagulation.

Short-term administration of testosterone induces a beneficial effect on exercise-induced myocardial ischemia in men with coronary artery disease. This effect may be related to a direct coronary-relaxing effect.

Background-We treated paroxysmal recurrent atrial fibrillation (AF) with radiofrequency (RF) catheter ablation by creating long linear lesions in the atria. To achieve line continuity, a 3D electroanatomic nonfluoroscopic mapping system was used. Methods and Results-In 27 patients with recurrent AF, a catheter incorporating a passive magnetic field sensor was navigated in both atria to construct a 3D activation map. RF energy was delivered to create continuous linear lesions: 3 lines (intercaval, isthmic, and anteroseptal) in the right atrium and a long line encircling the pulmonary veins in the left atrium. After RF application, the atria were remapped to validate completeness of the block lines, demonstrated by late activation of the areas circumscribed by the lines. The mean procedure duration was 312Ϯ103 minutes (range, 187 to 495), with mean fluoroscopy time of 107Ϯ44 minutes (range, 32 to 185 minutes). No acute complications occurred, but 1 patient experienced early prolonged sinus pauses and received a pacemaker. During the first day, 17 patients (63%) had AF episodes, but at discharge, 25 patients were in sinus rhythm. After a follow-up of 6.0 to 15.3 months (average, 10.5Ϯ3.0 months), 16 patients are asymptomatic, 3 have an almost complete disappearance of symptoms, 1 patient is improved, and 7 patients have their AF attacks unchanged. Conclusions-Paroxysmal recurrent drug-refractory AF can be treated by RF catheter ablation. Creation of long continuous linear lesions necessary to compartmentalize the atria is facilitated by a nonfluoroscopic electroanatomic mapping system. (Circulation. 1999;100:1203-1208.)