Radiofrequency (RF) ablation of idiopathic ventricular tachycardia (VT) has been demonstrated to be highly efficacious, but the efficacy RF VT in patients with coronary artery disease unknown. Therefore, purpose this study was determine feasibility disease.Fifteen consecutive and a history myocardial infarction underwent an attempt at 16 hemodynamically stable monomorphic VTs that had documented clinically on 12-lead ECG not successfully managed by pharmacological or device therapy. One...

The acute effect of atrial fibrillation (AF) on the effective refractory period (ERP) in humans is unknown.In 20 patients without structural heart disease, ERP was measured before and after pacing-induced AF at drive cycle lengths 350 500 ms. Immediately spontaneous conversion, post-AF measured. pre-AF ERPs ms were 206 +/- 23 216 17 ms, respectively. time to conversion 7.3 1.9 minutes. first 175 30 (P < .0001 versus pre-AF) 191 pre-AF), returned value a mean 8.4 0.3 In 15 patients, during...

The automatic ICD improves survival in patients with a history of sudden cardiac arrest. However, some do not meet the guidelines for implantation or are unable to receive an implantable device. This study tested hypothesis that these could benefit from wearable cardioverter defibrillator. Patients symptomatic heart failure and ejection fraction <0.30 (WEARIT Study) having complications associated high risk death after myocardial infarction bypass surgery receiving up 4 months (BIROAD were...

The combined role of atrial septal lead location and pacing algorithms in the prevention tachyarrhythmias (AT/AF), including both fibrillation flutter, is unknown. We tested hypothesis that could decrease AT/AF frequency patients with leads, bradycardia, paroxysmal AT/AF.A total 298 (age 70 +/- 10 years; 61% male) from 35 centers were implanted a DDDRP system three algorithms. Lead site was randomized at implant to right or nonseptal. Patients 1 month postimplant ON OFF for 3 months then...

Background Concealed entrainment has been useful in guiding catheter ablation of monomorphic ventricular tachycardia patients with coronary artery disease. However, not all sites concealed result successful the targeted tachycardia. The purpose this prospective study was to identify factors at that demonstrate differentiate effective from ineffective target sites. Methods and Results In 14 consecutive hemodynamically stable disease, radiofrequency 26 tachycardias performed. Ablation...

Background Ventricular pace mapping is performed by comparing the QRS morphology of ventricular paced complexes to that a template arrhythmia, either premature depolarization or complex during tachycardia. The objective this study was evaluate effect coupling interval and pacing cycle length on morphology. Methods Results population consisted 20 patients (mean age, 38±16 years) undergoing clinically indicated electrophysiology procedure. In first 10 patients, single evaluated visually signal...

Radiofrequency catheter ablation of accessory pathways and the atrioventricular junction often requires multiple applications energy. The inability to determine effects any given application on underlying tissue may contribute this problem. In present study, impedance was monitored in 20 patients undergoing radiofrequency ablation, relationship between an initial decrease subsequent were examined. An fall more than 10 omega 78% sensitive 88% specific for predicting evidence heating...

Background The purpose of this study was to examine the spatial resolution unipolar atrial pace mapping by pacing at adjacent sites within coronary sinus and right atrium. Methods Results Unipolar from each pole a quadripolar catheter performed in (n=29) atrium (n=10). Pacing distal electrode used simulate site origin an tachycardia. These P waves were compared with generated three proximal electrodes. analyzed for changes amplitude, duration, configuration. resulted significant amplitude...

Background High-density mapping studies of atrial fibrillation (AF) have suggested the presence an excitable gap. The purpose this study was to assess local and left response pacing at high right atrium during type I AF in humans. Methods Results Pacing performed 24 patients electrophysiology laboratory. assessed cycle lengths 10, 20, 30, 40, 50 ms less than mean baseline length. Digitized tracings tachycardia were recorded from distal coronary sinus. Computer analysis these signals used...

Radiofrequency lesions in the anterior, superior aspect of tricuspid annulus result selective elimination fast pathway function patients with typical atrioventricular (AV) nodal reentry tachycardia. This technique is simple and effective, but has been associated a significant risk inadvertent complete AV block. The purpose this study was to compare safety effectiveness two different techniques for radiofrequency catheter ablation pathway. Initially, fixed power output used at each target...

In a double-blind, placebo-controlled, single-dose, parallel-group study, oral doses (5, 10 and 25 mg) of the prostaglandin synthetase inhibitor bromfenac were compared with acetaminophen (1000 placebo for postoperative orthopedic pain. Analgesic measurements made by nurse observers use standard verbal rating visual analog scales. For most pain intensity relief measurements, 1000 mg was statistically superior to placebo, demonstrating assay sensitivity, better than both 5 ordinal ratings...

Implantable cardioverter‐defibrillator (ICD) generator replacement due to a depleted battery is frequently performed procedure. The frequency with which sensing and defibrillation system failures are identified during device procedures has not been previously described. Therefore, the purpose of this study was prospectively determine lead malfunction detected at time in 55 consecutive patients undergoing ICD replacement. mean age 63 ± 10 years 40 them were men. Forty‐nine had an epicardial...

Slow Pathway Ablation. Introduction : Successful radiofrequency ablation of an accessory pathway has been demonstrated to be associated with electrode‐tissue interface temperature approximately 60°C or impedance change −5 −10 Ω. However, the and changes AV nodal reentrant tachycardia (AVNRT) using slow approach have not reported. Therefore, purpose this study was define achieved during AVNRT. Methods Results The included 35 consecutive patients AVNRT undergoing a fixed power output 32 W,...

Impedance Versus Temperature Monitoring. Introduction : The purpose of this study was to prospectively compare the value impedance and temperature monitoring during accessory pathway ablation. can be used radiofrequency ablation pathways titrate power achieve adequate but not excessive tissue beating. Methods Results One hundred thirty‐two patients with a single were randomly assigned undergo using either or monitoring. During monitoring, endpoint for titration 5‐to 10‐Ω decrease in measured...