Underwent Device Replacement Research Articles

Longevity of the Subcutaneous Implantable Defibrillator: Long-Term Follow-Up of the European Regulatory Trial Cohort.

The recent advent of subcutaneous implantable cardioverter defibrillators (S-ICDs) has provided investigators with a safe and effective new therapy in patients at risk of sudden cardiac death. At present, no data are available with regard to the longevity of these new devices. This study evaluated the longevity of the S-ICD system. All patients enrolled in the European Regulatory Trial were included in the analysis. During follow-up, time and causes of device replacement or explantation were assessed and categorized. Device longevity was estimated using Kaplan-Meier analysis. Fifty-five patients were followed for a median of 5.8 years. During follow-up, 26 (47%) patients underwent device replacement and 5 (9%) underwent device explantation. Median time to replacement was 5.0 years (Q1-Q3, 4.4-5.6 years). Replacement was caused by battery depletion in 25 patients (92%), of which 5 within 1.5 years because of premature battery depletion, and by infection in 1 patient (2%). Replacement for a transvenous ICD system was required in 4 patients (7%) because of ineffective defibrillation in 1 (0.003 per patient-year), need for resynchronization therapy in 2 (0.01 per patient-year), and for antibradycardia pacing in 1 (0.003 per patient-year). At 5 years follow-up, 71% of devices were still in service. This study provides the first estimate of S-ICD system longevity since its introduction in clinical practice. Median longevity of the first generation S-ICD system was 5.0 years. The majority of devices were replaced because of battery depletion. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01117792.

IMpact of pocKet rEvision on the rate of InfecTion and other CompLications in patients rEquiring pocket mAnipulation for generator replacement and/or lead replacement or revisioN (MAKE IT CLEAN): A prospective randomized study.

The fibrous capsule around cardiac implantable device generators is known to promote bacterial colonization and latent infection. Removal of the capsule during device replacement procedures may reduce infection rates but may increase hemorrhagic complications. The purpose of this study was to evaluate the effect of pocket capsule decortication procedure on infection and bleeding rates in patients undergoing device replacement procedures. In a prospective randomized single-blind control study, patients undergoing device replacement, upgrade, or lead extraction were randomized to Group A "with pocket revision" (n = 131) and group B "without pocket revision" (n = 127). Deep and superficial infection rates, bleeding, and prolonged serous drainage were assessed during 12 months of follow-up. Data were analyzed according to intention-to-treat principle. A total of 258 patients were enrolled in the study. Rates of generator change, upgrade, and lead extraction/replacement were similar between both groups. There was no incidence of deep infection in either group at 12-month follow-up. There was no significant difference in the incidence of superficial infection between groups (1.5% vs 4.7%, P = .13) during 12-month follow-up. There was a significant increase in acute hematoma formation in group A compared to group B (6.1% vs 0.8%, P = .03). Two patients in group A had to undergo hematoma evacuation. There was increased incidence of hematoma formation in group A with no effect on infection rates. Our study suggests that there is no benefit to performing empiric pocket revision.

Outcomes After Implantable Left Ventricular Assist Device Replacement Procedures

As the duration of support increases for patients with continuous flow left ventricular assist devices (LVADs), device replacement may still be necessary for a variety of indications. Outcomes after replacement LVAD surgeries have not been extensively described, and whether these patients experience outcomes similar to primary LVAD implant patients remains unclear. From 2003 to 2012, 342 consecutive implantable LVAD procedures took place at a single institution, of which 201 were considered destination therapy. Within this larger group, 30 patients underwent 35 replacement procedures. The three major indications for replacement LVAD procedures were mechanical/electrical failure (57%), hemolysis/thrombosis (29%), and infection (14%). Propensity matching using preoperative characteristics was used to generate a primary implant control group to determine the impact of the replacement status on outcomes. Thirty-day and 1-year survival after LVAD replacement was 90% and 48%, respectively. Survival outcomes were worse for patients undergoing device replacement compared with the matched primary cohort (p = 0.03). The need for transfusion and the incidence of postoperative right ventricular and renal dysfunction were similar between the two groups, as was length of hospitalization. There was no difference between the rates of postoperative infection or stroke. Emergent replacement procedures had a higher mortality than those done nonemergently. Given these findings, earlier timing for replacement, temporary stabilization with an extracorporeal device, and use of a nonsternotomy surgical approach should be investigated as strategies to improve outcomes.

Twiddler syndrome with 180° rotation of an implantable cardioverter defibrillator generator resulting in malfunction of one of the shocking coils

A 78-year-old woman with non-ischaemic cardiomyopathy received a prophylactic single-chamber implantable cardioverter defibrillator (ICD) and later underwent device replacement for battery depletion (Current VR, St Jude Medical Inc., …

Complications of replacing implantable devices in response to advisories: A single center experience

Background Advisories for implanted devices present a challenging management problem since no specific guidelines exist for device replacement under these circumstances. Since the rate and severity of complications is an important factor in the decision-making, we sought to review our experience with replacement of devices under advisory. Methods Medical records of patients with devices under advisory were reviewed. A total of 237 patients (age 68 ± 13 years, men 71%, implantable cardioverter-defibrillator (ICD) 87%) underwent device replacement in response to advisories (Medtronic Inc. 43% and Guidant Inc. 57%) at our institution between February 2005 and June 2006. Results The mean time from original device implantation to replacement was 31 ± 16 months (3–73 months). During a mean follow-up of 198 ± 103 days, there was a 5.5% overall rate of complications related to the procedure. Major complications requiring re-operation affected 2.1% of patients. There were no deaths associated with device replacement. Device failure prior to replacement was documented in 1.7% of patients, with syncope occurring in one patient. A history of diabetes mellitus (23%), peripheral vascular disease (4%), obstructive lung disease (7%), end-stage renal disease (2%), or use of anticoagulation (44%) did not predict the occurrence of complications after advisory device replacement. Conclusion This single center experience shows a lower major complication rate from replacement of devices under advisory than previously reported. Experience from this center and others may be useful in guiding future management of patients in the setting of device advisories.

Complications Associated with Generator Replacement in Response to Device Advisories

Device recalls create problems for patients and physicians, for the risks associated with replacement may be greater than the device failure rate. In 2005, Medtronic, Guidant, and St. Jude had implantable cardioverter defibrillator (ICD) recalls on several of their devices. There were no national standards to guide physicians on the management of such patients. We report the reasons for and outcomes of ICD and pacemaker generator changes from our practice resulting from these advisories. After an advisory was issued, the patients with an affected device were contacted, evaluated in the office by one of the electrophysiologists in our group, and a management plan was determined. Two hundred and twenty-two of 1,039 (Medtronic 273, Guidant 766) (21.4%) patients with advisory devices underwent device replacement. Nine minor complications occurred: hematoma managed conservatively (n = 6); local discomfort (n = 1); and incisional infections treated successfully with oral antibiotics (n = 2). Major complications occurred in nine patients (4.1%). Four atrial leads were damaged, two of which were repaired, one during the same procedure and the other at a later date. One patient required a reoperation to tighten a loose ventricular lead set screw. Hematoma requiring evacuation occurred in one patient, and pocket revision was necessary in two patients secondary to severe discomfort due to the positioning of the device in the pocket. One patient had a cerebrovascular accident preoperatively. There were no perioperative deaths or infections requiring system removal. Even with experienced operators complications can occur when replacing generators for a device recall. Careful risk assessment for each individual patient should be performed and efforts made to minimize generator changes.

Indications for predismissal testing with arrhythmia-induction in patients receiving an implantable cardioverter defibrillator

Arrhythmia induction during implantation of cardioverter defibrillators (ICD) is a standard procedure. However, controversy exists regarding the need for routine arrhythmia induction before discharge from hospital (pre-hospital discharge (PHD) test). In order to reduce the number of tests we identified risk factors that predict relevant ICD malfunction. 965 patients receiving a first device implantation (n=724) or device/system replacement (n=241) between 1998 and 2004 were analysed. During implantation 176 (18%) complications (intraoperative undersensing of induced arrhythmias, unsuccessful arrhythmia-therapy or low DFT safety margin) occurred. Frequent (>4 times) intraoperative lead repositioning due to low sensing values was present in 44 patients (5%). 9% of the patients with first ICD implantation, 21% with device replacement and 27% with system replacement developed complications during PHD testing with arrhythmia induction. Intraoperative complications, although corrected during implantation, were independent risk factors for malfunction during PHD testing (p<0.05). Additional predictors for malfunction were intraoperative lead repositioning (>4 times) and a history of both VF and VT (p<0.05). Patients without intraoperative complications rarely developed malfunction during PHD testing (3.7% first device, 6.25% system replacement). Only in patients undergoing device replacement was a higher risk for failure (13%) evident. No risk factors could be identified for these subgroups. Routine arrhythmia induction during PHD is recommended in ICD patients with intraoperative complications, although corrected during implantation, as well as frequent intraoperatives lead repositioning. Patients undergoing device/system replacement uncomplicated implantation are not generally at low risk for device failure.

Identification of Device Malfunction in Patients Supported With the HeartMate XVE Left Ventricular Assist System

Predicting end-of-life for left ventricular assist devices is important to determine timing of device removal. A retrospective analysis was performed on 46 patients undergoing implantation of the latest HeartMate XVE from July 1, 2003, through March 31, 2006. Devices were assessed by analysis of motor current waveforms and quantification of the titanium or copper particles within dust localized to the driveline vent filter by optical, polarized light, scanning electron microscopy, and energy dispersive x-ray spectroscopy. Assessments were performed monthly for patients supported > or =330 days or for unexpected device alarms. Thirty-one (67%) patients were supported for <330 days and 15 (33%) were supported for > or =330 days. No malfunctions occurred in patients supported <330 days. For patients supported > or =330 days, five had abnormal current waveforms or copper and titanium dust localized to the vent filter. One underwent urgent transplantation, three underwent device replacement (one death; two ongoing), and one is with ongoing support. Of the remaining 10 patients, seven underwent transplantation; two remain on device; and one died while on left ventricular assist device support. There were no unexpected device failures. Bearing wear of the HeartMate XVE is predictable by analysis of current waveforms or titanium and copper dust within the vent filter.