Value of pre-hospital discharge defibrillation testing in recipients of implanted cardioverter defibrillators.

Opinions vary regarding the need to perform defibrillation testing prior to hospital discharge in recipients of state-of-the-art cardioverter defibrillators (ICDs). Our protocol is to perform predischarge ICD testing 1 day after implant. This report includes 682 consecutive implants. Adverse observations at testing were grouped into (1) risk of defibrillation failure, (2) surgical complications, (3) sensing/pacing issues or narrow defibrillation margin warranting closer follow-up, or (4) findings correctable by device reprogramming. Among the 682 patients, 63% had single-chamber and 37% dual-chamber or biventricular ICDs. In 48 patients (7%) there were 69 concerns and/or interventions, with overlaps among the four categories, including one failure to defibrillate (0.15%), and six other patients at risk. Surgical complications included 11 hematomas (1.6%), and six lead dysfunctions. Closer follow-up was indicated in 19 patients (2.7%), for high pacing thresholds in seven, sensing issues in seven, and <10 J defibrillation margin in five. Device reprogramming was needed in 31 patients (4.5%), for tachycardia detection and therapy settings in 12, and for pacing/sensing functions in 22 patients. In eight patients ventricular fibrillation could not be induced. There was no morbidity or mortality due to testing. The state-of-the-art ICDs delivering biphasic shocks are remarkably reliable. The routine pre-hospital discharge defibrillation testing of such ICDs may be optional and left to the physicians' discretion.

Lead stuck (frozen) in header: salvage by bone cutter versus other techniques. jfisher@montefiore.org.

It is occasionally difficult to disconnect leads from headers at the time of pulse generator replacement without injuring the fragile leads. Over a 2.5-year period we encountered this problem in six cases (1.7% of pulse generator replacements). The posterior portion of the header was clipped off using an orthopedic bone cutter in four cases. The cut was aligned with the deep end of the lead socket in the header. A metal rod was then used to push the lead out of the socket. Bench testing of alternative methods was done on previously explanted pulse generators that were firmly held in a vice. Motorized microtools were used to drill holes from the end of the header to the deep end of the socket; or with a rotary saw attachment to slice off the back of the header, allowing a retained lead to be pushed out. The latter was also done with a hand held razor saw, and attempts were made with a scalpel. Lead removal in the clinical cases was accomplished quickly in the four cases using the bone-cutter, without trauma to the lead. Bench testing results varied. The bone cutter was the most efficient method for most brands, but was ineffective on one. The motorized tool was difficult to position, produced sprays of plastic particles, and would have been risky in a clinical setting. The razor saw was difficult to use safely, or efficiently, except in some headers that resisted the bone cutter. The scalpel failed except in one "soft header" pacemaker. An orthopedic bone cutter is a useful tool for removing a retained lead from a pulse generator header. Different header designs and materials necessitate knowledge of several lead detachment methods.