Ellison Berns

Feasibility of Radiofrequency Powered, Thermal Balloon Ablation of Atrioventricular Bypass Tracts Via the Coronary Sinus: In Vivo Canine Studies

Radiofeequency catheter ablation of left sided accessory pathways is technically demanding and usually requires left heart catheterization. The feasibility of creating lesions from within the coronary sinus of sufficient size to ablate accessory pathways in humans using a thermal balloon catheter was studied in 20 dogs. In group 1 (n == 14), 17 thermal inflations were performed in 12 dogs at either 70°, 80°, or 90°C each for 30 or 60 seconds (in 2 dogs two non‐thermal control inflations were performed). Animals were sacrificed 6.3 ± 1.6 days later. In group 2 (n = 6), seven thermal inflations were performed at 90°C each for 180, 300, or 360 seconds. Group 2 animals received antiplatelet and anticoagulant therapy for 1 week and were sacrificed at 13 ± 10.7 days. In both groups, hemodynamic, angiographic, and electrocardiographic studies were performed at baseline, 1 hour after inflation, and prior to sacrifice. All dogs remained clinically stable throughout the procedure and no complications were attributed to the effect of thermal inflation. Thermal lesions measured 14.4 ± 4.4 mm in length and extended from the coronary sinus intima to a mean depth of 2.9 ± 1.2 mm (range 1.4‐6.5 mm). Group 2 lesions were significantly deeper than group 1 lesions (P = 0.03). Of the 24 thermal lesions created, atrial necrosis was present in 23 and ventricular necrosis in 11. In all lesions there was some degree of either atrial necrosis, ventricular necrosis, or both. A variable degree of coronary sinus thrombus was present in 18 dogs without clinical sequelae. It is concluded that radiofrequency balloon heating via the coronary sinus can create thermal lesions in the atrioventricular sulcus of dogs that may be of sufficient size to ablate accessory left‐sided pathways in humans. (PACE 1995; 18: 1518‐1530)

De novo monomorphic and polymorphic ventricular tachycardia following coronary artery bypass grafting

We compared de novo monomorphic and polymorphic ventricular tachycardia (VT) occurring after coronary artery bypass graft surgery in 21 patients. Our findings support an underlying arrhythmogenic substrate for de novo monomorphic VT, whereas polymorphic VT is more likely related to transient perioperative abnormalities.

Predictors of conversion of atrial fibrillation after cardiac operation in the absence of class I or III antiarrhythmic medications.

BACKGROUND Although risk factors for the development of atrial fibrillation (AF) after cardiac operations have been studied extensively, predictors of conversion to sinus rhythm within 24 hours of onset have not been examined. METHODS Eleven hundred consecutive adults undergoing cardiovascular operations from July 1997 to June 1998 were screened for new onset AF after operation. Patients with chronic persistent preoperative AF or those who died within 48 hours of the operation were excluded. RESULTS Three hundred fifty-three patients develop

Advanced heart block and atrial flutter in a patient with HLA B27 spondyloarthropathy.

An athletic 43-year-old man presented with symptomatic bradycardia and atrial flutter after being diagnosed with HLA B27 associated spondyloarthropathy several months earlier. The patient was admitted and underwent electrophysiology evaluation with ablation of his atrial flutter and eventually underwent pacemaker implantation. His cardiac workup showed a structurally normal heart and strongly suggested that his HLA B27 associated spondyloarthropathy was responsible for his presentation. A review of the literature suggests that HLA B27 spondyloarthropathy related heart block may be an often overlooked cause of heart block in otherwise healthy patients.

Early Antiarrhythmic Therapy Is No Better than Rate Control Therapy Alone for Suppression of Atrial Fibrillation After Cardiac Surgery

Background: Despite recent advances in therapy for atrial fibrillation (AF) following cardiac surgery, the potential superiority of antiarrhythmics over rate control therapy for suppression of AF has not been convincingly demonstrated. We sought to determine whether early treatment of AF following cardiac surgery with antiarrhythmics improves clinical outcome, as measured by recurrence rate, length of stay, and adverse events.

Analysis of Complications in Outpatient ICD Surgery On or Off Warfarin Anticoagulation.

Implantable cardioverter defibrillator (ICD) implantation is being performed differently at many hospitals, with some keeping patients overnight after procedure while others discharge patients home same day. In addition, many centers are now performing ICD surgery while on warfarin anticoagulation. There are, however, limited data on outpatient ICD surgery on anticoagulated (AC) patients.

A Prospective Study Comparing the Sensed R Wave in Bipolar and Extended Bipolar Configurations: The PropR Study

Progress in implantable cardiac defibrillator (ICD) technology has allowed for switching the sensing polarity for the detection of ventricular fibrillation (VF). However, whether one sensing polarity confers additional advantage over the other is not known.