Robert Sorrentino

Pacemaker Lead Extraction With the Laser Sheath: Results of the Pacing Lead Extraction With the Excimer Sheath (PLEXES) Trial

OBJECTIVES The purpose of this study was to evaluate the safety and effectiveness of pacemaker lead extraction with the excimer sheath in comparison to nonlaser lead extraction. BACKGROUND Fibrotic attachments that develop between chronically implanted pacemaker leads and to the venous, valvular and cardiac structures are the major obstacles to safe and consistent lead extraction. Locking stylets and telescoping sheaths produce a technically demanding but effective technique of mechanically disrupting the fibrosis. However, ultraviolet excimer laser light dissolves instead of tearing the tissue attachments. METHODS A randomized trial of lead extraction was conducted in 301 patients with 465 chronically implanted pacemaker leads. The laser group patients had the leads removed with identical tools as the nonlaser group with the exception that the inner telescoping sheath was replaced with the 12-F excimer laser sheath. Success for both groups was defined as complete lead removal with the randomized therapy without complications. RESULTS Complete lead removal rate was 94% in the laser group and 64% in the nonlaser group (p = 0.001). Failed nonlaser extraction was completed with the laser tools 88% of the time. The mean time to achieve a successful lead extraction was significantly reduced for patients randomized to the laser tools, 10.1 +/- 11.5 min compared with 12.9 +/- 19.2 min for patients randomized to nonlaser techniques (p < 0.04). Potentially life-threatening complications occurred in none of the nonlaser and three of the laser patients, including one death (p = NS). CONCLUSIONS Laser-assisted pacemaker lead extraction has significant clinical advantages over extraction without laser tools and is associated with significant risks.

Catheter ablation of sinoatrial node reentrant tachycardia

OBJECTIVES This study evaluates 1) the safety and efficacy of catheter delivery of radiofrequency current to eliminate sustained sinoatrial node reentrant tachycardia; 2) the incidence of sinoatrial node reentrant tachycardia in the current group of patients undergoing electrophysiologic study for paroxysmal supraventricular tachycardia; and 3) the association of sinoatrial node reentrant tachycardia with other tachyarrhythmias. BACKGROUND Sustained sinoatrial node reentrant tachycardia is an uncommon cause of paroxysmal supraventricular tachycardia that is reported to occur infrequently in conjunction with other arrhythmias. Although pharmacologic and surgical therapies are available, there is limited information with regard to catheter ablation of sinoatrial node reentrant tachycardia. METHODS Ten patients with sustained sinoatrial node reentrant tachycardia underwent electrophysiologic study and radiofrequency current ablation. Patients were followed up for 9.2 +/- 6.0 months. RESULTS Of 343 consecutive patients referred for electrophysiologic evaluation of paroxysmal supraventricular tachycardia, 11 (3.2%) were found to have inducible sustained sinoatrial node reentrant tachycardia. Nine of the 11 patients had other associated arrhythmias, including atrioventricular (AV) node reentrant tachycardia (6 patients), AV reciprocating tachycardia (2 patients), ectopic atrial tachycardia (2 patients) and bundle branch reentrant tachycardia (1 patient). In 10 patients, direct ablation of sinoatrial node reentrant tachycardia was attempted and was successful in all (confidence interval for failure 0-0.26). Sinoatrial node reentrant tachycardia was eliminated with a median of four radiofrequency current applications (range 1 to 10) at 20 to 30 W. Successful ablation site characteristics during sinoatrial node reentrant tachycardia included 1) atrial activation > or = 35 ms (mean 44 +/- 8 ms) before the onset of the surface P wave, 2) atrial activation > or = 20 ms (mean 28 +/- 6 ms) before the onset of high right atrial activation, and 3) significantly prolonged and fractionated electrograms (mean duration 87 +/- 21 ms). No complications were encountered, and there have been no recurrences of sinoatrial node reentrant tachycardia. CONCLUSIONS Sinoatrial node reentrant tachycardia may be effectively and safely treated with radiofrequency current ablation at the site of earliest atrial activation.

BUNDLE BRANCH REENTRY TACHYCARDIA AND POSSIBLE SUSTAINED INTERFASCICULAR REENTRY TACHYCARDIA WITH A SHARED UNUSUAL INDUCTION PATTERN

Bundle Branch Reentry and Interfascicular Reentry. A case of bundle branch reentry tachycardia with an unusual induction pattern is presented. Unlike typical cases of this arrhythmia in which tachycardia is usually inducible with routine programmed ventricular stimulation and/or short‐long sequences, tachycardia in this case was inducible only with atrial stimulation. It also arose spontaneously during atrial flutter and during isoproterenol administration. After ablation of the right bundle, possible interfascicular reentry tachycardia with a similar induction pattern was observed. This tachycardia was successfully ablated in the region of the posterior fascicle of the left bundle branch.

AN UNUSUAL CASE OF VENTRICULAR FIBRILLATION

A 46-year-old woman was brought by ambulance to the emergency room, having suffered a transient loss of consciousness at home. The admission vital signs were a pulse of 127 beats/min and a blood pressure of 116/80 mmHg. After an ECG was obtained (Fig. 1), intravenous lidocaine (175 mg in divided doses) and magnesium sulfate were administered, without change in either her cardiac rhythm or hemodynamic status. She was then sedated and cardioverted with 100 J, after which she hecame pulseless and apneic. She was successfully defibrillated on the second attempt with 360 J. An ECG was then obtained (Fig. 2). Cardiac isoenzymes peaked at 406 IU/L with 16 units MB. Serum potassium was 2.8 mEq/L immediately following her resuscitation, which rose to 4.0 with the administration of 20-mEq intravenous potassium.

RISK STRATIFICATION SCORING PREDICTS MORTALITY IN DIALYSIS PATIENTS WITH ATRIAL FIBRILLATION

The CHA2DS2VASc score predicts stroke occurrence and mortality in atrial fibrillation (AF) patients. AF and End Stage Renal Disease (ESRD) share many risk factors including heart failure, hypertension, and diabetes. Patients with ESRD and AF may exhibit some or all of these risk factors, suggesting

Multiuser clinical electrophysiology database using low-cost PCs in a Novell Netware Environment

A multiuser database has been developed by the Duke University Medical Centers clinical electrophysiology (EP) group that runs on low-cost IBM compatible PCs running in a Novell Netware Environment and is written in the FoxPro programming language. The authors describe the functioning of the Duke EP database and illustrate how networked PCs in combination with the powerful database development systems now available can be employed by end-users to solve problems quickly and economically. The functions provided by the Duke EP database include storage of patient information, procedure report generation, quality assurance monitoring, intrahospital billing, clinic scheduling, and implantable cardiac defibrillator monitoring. The system incorporates features such as pop-up menus for data entry, step-by-step instructions, and an online help system to make it easy to use by nontechnical personnel. The effectiveness and cost of the system are discussed.<<ETX>>