Assessing the Risks Associated with MRI in Patients with a Pacemaker or Defibrillator.

BACKGROUND: The presence of a cardiovascular implantable electronic device has long been a contraindication for the performance of magnetic resonance imaging (MRI). We established a prospective registry to determine the risks associated with MRI at a magnetic field strength of 1.5 tesla for patients who had a pacemaker or implantable cardioverter-defibrillator (ICD) that was "non-MRI-conditional" (i.e., not approved by the Food and Drug Administration for MRI scanning). METHODS: Patients in the registry were referred for clinically indicated nonthoracic MRI at a field strength of 1.5 tesla. Devices were interrogated before and after MRI with the use of a standardized protocol and were appropriately reprogrammed before the scanning. The primary end points were death, generator or lead failure, induced arrhythmia, loss of capture, or electrical reset during the scanning. The secondary end points were changes in device settings. RESULTS: MRI was performed in 1000 cases in which patients had a pacemaker and in 500 cases in which patients had an ICD. No deaths, lead failures, losses of capture, or ventricular arrhythmias occurred during MRI. One ICD generator could not be interrogated after MRI and required immediate replacement; the device had not been appropriately programmed per protocol before the MRI. We observed six cases of self-terminating atrial fibrillation or flutter and six cases of partial electrical reset. Changes in lead impedance, pacing threshold, battery voltage, and P-wave and R-wave amplitude exceeded prespecified thresholds in a small number of cases. Repeat MRI was not associated with an increase in adverse events. CONCLUSIONS: In this study, device or lead failure did not occur in any patient with a non-MRI-conditional pacemaker or ICD who underwent clinically indicated nonthoracic MRI at 1.5 tesla, was appropriately screened, and had the device reprogrammed in accordance with the prespecified protocol. (Funded by St. Jude Medical and others; MagnaSafe ClinicalTrials.gov number, NCT00907361 .).

Transcatheter aspiration of large pacemaker and implantable cardioverter-defibrillator lead vegetations facilitating safe transvenous lead extraction.

AIMS: Treatment of patients with systemic cardiac implantable electronic device (CIED) infection with large lead vegetations is challenging and associated with relevant morbidity and mortality. To avoid complications from open surgical extraction, a novel approach with percutaneous aspiration of large vegetations prior to transvenous lead extraction was instituted. The results of this treatment concept were retrospectively analysed in this multicentre study. METHODS AND RESULTS: One hundred and one patients [mean age 68.2 ± 13.1 (30-92) years] were treated in four centres for endovascular CIED infection with large lead vegetations. Mean lead vegetation size was 30.7 ± 13.5 mm. Two hundred and forty-seven leads were targeted for extraction (170 pacemaker leads, 77 implantable cardioverter-defibrillator leads). Mean lead implant duration was 81.7 (1-254) months. The transcatheter aspiration system with a specialized long venous drainage cannula and a funnel-shaped tip was based on a veno-venous extracorporeal circuit with an in-line filter. The aspiration of vegetations showed complete procedural success in 94.0% (n = 95), partial success in 5.0% (n = 5). Three major complications (3.0%) were encountered. Complete procedural success (per lead) of the subsequently performed transvenous lead extraction procedure was 99.2% (n = 245). Thirty-day mortality was 3.0% (n = 3). Five patients (5.0%) died in the further course on Days 51, 54, 68, 134, and 182 post-procedure (septic complications: n = 4; heart failure: n = 1). CONCLUSION: The percutaneous aspiration procedure is highly effective and is associated with a low complication profile. The aspiration of vegetations immediately prior and during the lead extraction procedure may avoid septic embolization into the pulmonary circulation. This may potentially lead to a long-term survival benefit.

Multicenter experience with transvenous lead extraction of active fixation coronary sinus leads.

BACKGROUND/OBJECTIVE: Active fixation coronary sinus (CS) leads limit dislodgement and represent an attractive option to the implanter. Although extraction of passive fixation CS leads is a common and frequently uncomplicated procedure, data regarding extraction of chronically implanted active fixation CS leads are limited. METHODS: We performed a retrospective cohort study of patients undergoing active fixation CS lead extraction at six centers. Patient and procedural characteristics, indications for extraction, use of extraction sheath (ES) assistance, and outcomes are reported. RESULTS: Between January 2009 and February 2011, 12 patients underwent transvenous lead extraction (TLE) of Medtronic StarFix® lead (Medtronic Inc., Minneapolis, MN, USA). The cohort was 83% male with mean age 71 ± 14 years. Average implant duration was 14.2 ± 5.7 months (2.3-23.6). All leads but one were removed for infectious indications (67% systemic infection). At the time of explant, the fixation lobes were completely retracted in only one of the 12 cases and ES assistance was required for lead removal in all cases (58% laser, 25% cutting, 25% mechanical, and 25% femoral). The majority of cases required advancement of the sheath into the CS (75.0%) and often into a branch vessel (41.7%). One lead could not be removed transvenously and required surgical lead extraction. There were no major complications. Examination of the leads after extraction frequently revealed significant tissue growth into the fixation lobes. CONCLUSIONS: Although TLE of active fixation CS leads can be a safe procedure in select patients and experienced hands, powered sheaths and aggressive techniques are frequently required for successful removal despite relatively short implant durations. This raises significant concern regarding future TLE of active fixation CS leads with longer implant durations.

Percutaneous Vacuum-Assisted Thrombectomy Device Used for Removal of Large Vegetations on Infected Pacemaker and Defibrillator Leads as an Adjunct to Lead Extraction.

This case series reports our early experience with a minimally invasive percutaneous method of safely removing large vegetations during lead extraction in septic cardiac implantable electronic devices (CIED). Debate exists concerning the management of vegetations involving these devices. Lead extraction is mandated for infections, but vegetations may embolize, causing complications. Surgical debridement is recommended; alternatives include cardiopulmonary bypass, minimally invasive thoracotomy, or transatrial approaches. The AngioVac device allows percutaneous right heart bypass and suction removal of vegetations under echocardiographic and fluoroscopic guidance. This case series describes our first 20 patients, all critically ill with persistent sepsis and vegetations despite long-term antibiotics. This series includes patients who would not have been eligible for alternative procedures due to contraindications and highlights the potential role of this new technology.