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Published on: February 28, 2012
Initial clinical experience with implantable loop recorders
H Mieszczanska1, B Ibrahim, T J Cohen
1Director of Electrophysiology, Winthrop University Hospital, 259 First St., Mineola, NY 11501, USA.
The purpose of this study was to review the initial experience of a university hospital with Implantable Loop Recorders (ILR) for diagnosis of recurrent unexplained syncope or presyncope. Twelve patients with syncope or presyncope of unknown etiology (who had a negative tilt table test, electrophysiologic study, and neurologic work-up) underwent implantation of ILR. All implants were performed using the Reveal ILR (Medtronic AVE, Santa Rosa, California). The 8 cc device is 61 mm long, 19 mm wide, 8 mm thick and weighs 17 grams. It has 18 months of battery life and has 2 electrodes with 38.5 mm spacing. The device is nonvascular and is implanted approximately 2 fingerbreadths below the clavicle in a subcutaneous pocket (1.5 inches long) and is secured via polydacron suture to the pre-pectoral fascia/pectoralis muscle. Twelve patients with a mean age of 61 +/- 22 years received the ILR. Ten patients had syncope and 2 had presyncope. Three patients had coronary artery disease and 2 had dilated cardiomyopathy. ILRs were implanted for a mean follow-up period of 7.2 +/- 5.8 months (range, 1 day to 18 months). Two patients still continue to be monitored at the time of this report. The mean number of events prior to ILR was 6.0 +/- 5.4. Eight patients (66%) had recurrent syncope after implantation. One patient was not available for follow-up. There were no significant complications from the implant. In 5/12 patients (42%), the ILR helped to diagnose the etiology of the syncopal episode. Syncope was secondary to asystole in three patients, junctional bradycardia in another patient, and seizure activity in a fifth patient (high-frequency noise recorded on the electrocardiogram during sinus rhythm). The 4 patients with ILR-documented bradyarrhythmias underwent permanent pacemaker implantation and are alive and well. ILR implantation is a simple, useful and safe method in assisting with the diagnosis of recurrent unexplained syncope or presyncope after an inconclusive electrophysiologic and neurologic evaluation.
The purpose of this study was to review the initial experience of a university hospital with Implantable Loop Recorders (ILR) for diagnosis of recurrent unexplained syncope or presyncope. Twelve patients with syncope or presyncope of unknown etiology (who had a negative tilt table test, electrophysiologic study, and neurologic work-up) underwent implantation of ILR. All implants were performed using the Reveal ILR (Medtronic AVE, Santa Rosa, California). The 8 cc device is 61 mm long, 19 mm wide, 8 mm thick and weighs 17 grams. It has 18 months of battery life and has 2 electrodes with 38.5 mm spacing. The device is nonvascular and is implanted approximately 2 fingerbreadths below the clavicle in a subcutaneous pocket (1.5 inches long) and is secured via polydacron suture to the pre-pectoral fascia/pectoralis muscle. Twelve patients with a mean age of 61 +/- 22 years received the ILR. Ten patients had syncope and 2 had presyncope. Three patients had coronary artery disease and 2 had dilated cardiomyopathy. ILRs were implanted for a mean follow-up period of 7.2 +/- 5.8 months (range, 1 day to 18 months). Two patients still continue to be monitored at the time of this report. The mean number of events prior to ILR was 6.0 +/- 5.4. Eight patients (66%) had recurrent syncope after implantation. One patient was not available for follow-up. There were no significant complications from the implant. In 5/12 patients (42%), the ILR helped to diagnose the etiology of the syncopal episode. Syncope was secondary to asystole in three patients, junctional bradycardia in another patient, and seizure activity in a fifth patient (high-frequency noise recorded on the electrocardiogram during sinus rhythm). The 4 patients with ILR-documented bradyarrhythmias underwent permanent pacemaker implantation and are alive and well. ILR implantation is a simple, useful and safe method in assisting with the diagnosis of recurrent unexplained syncope or presyncope after an inconclusive electrophysiologic and neurologic evaluation.
