Effects of a Thin-Sized Lead Body of a Transvenous Single Coil Defibrillation Lead on ICD Implantation

SCHUCHERT, A., et al. : Effects of a Thin‐Sized Lead Body of a Transvenous Single Coil Defibrillation Lead on ICD Implantation. In the interest of patients receiving implantable cardioverter defibrillators (ICDs), the clinical benefits of newer and thinner transvenous defibrillation leads have to be determined. The aims of this study were to evaluate the ICD procedure duration and the frequency of lead dislocation at the 3‐month follow‐up of a new defibrillation lead with a thin‐sized lead body and its conventionalsized predecessor. The thin‐sized single coil defibrillation lead (Kainox RV, Biotronik; lead body 6.7 Fr) was implanted in 61 patients and the conventional‐sized defibrillation lead (SPS, Biotronik; lead body 7.8 Fr) in 60 patients. Both leads were connected to a left‐sided, prepectorally implanted Phylax ICD (Biotronik) with active housing. The lead implantation time and total procedure duration were determined. Lead implantation time was defined as the time from lead insertion to the end of the pacing measurements. The total procedure duration spanned skin incision to closure. The incidence of lead repositioning during the lead implantation time and during ventricular fibrillation conversion testing was also assessed. The frequency of lead dislocations was recorded at the 3‐month follow‐up. Mean lead implantation time and total procedure duration of the thin‐sized lead (23 ± 22 minutes 76 ± 37 minutes ) were not statistically different from the time needed for the conventional‐sized lead (22 ± 20 minutes 81 ± 34 minutes ). The number of lead repositionings during the lead implantation time was similar (thin‐sized lead: 1.4 ± 2.4 ; conventional‐sized lead: 1.1 ± 1.9 ). An additional lead repositioning was not necessary during ventricular fibrillation conversion testing in 93.4% of the patients with thin‐sized and in 94.4% with conventional‐sized leads (not significant). At the 3‐month follow‐up, there were four (6.6%) lead dislocations in the thin‐sized and four (6.7%) in the conventional‐sized lead group. In conclusion, the downsized lead body of the new defibrillation lead influenced neither ICD procedure duration nor the incidence of lead dislocation during follow‐up.     

Limitation of Programmed Alerts to Predict ICD Lead Failures

A 75-year-old man with a Sprint Fidelis ICD lead (Medtronic Inc., Minneapolis, MN, USA) experienced inappropriate shocks after sudden failure of the right ventricular (RV) pace-sense connector resulting in noise. Interrogation of the implantable cardioverter-defibrillator pulse generator revealed that the 3 AM daily measurement of RV pacing impedance was slightly higher (750 Ω) than the baseline (∼450–550 Ω )(although below the recommended alert level of 1,000 Ω ) and markedly higher at 4 AM (1,552 Ω ) when therapies were delivered. The event occurred before the patient could be alerted by the audible tones. Thus, the manufacturer's recommended impedance monitoring alert parameters will not predict all lead failures .     

Right Ventricular Perforation with an ICD Defibrillation Lead Managed by Surgical Revision and Epicardial Leads—Case Reports

The authors present two cases of patients with perforation of the right ventricular wall by the implantable cardioverter defibrillator (ICD) lead. The complication was resolved by cardiosurgical revision and epicardial leads stitched onto the diaphragmatic wall of the heart. The perforation was identified by electrical parameter changes of the leads, echocardiography, and computed tomography. Both patients had satisfactory values of electrical parameters and ICD function with epicardial leads. The importance of regular follow-up and a check of the lead parameters are emphasized.     

Delayed ICD lead cardiac perforation: comparison of small versus standard-diameter leads implanted in a single center

Background: An increased risk of delayed cardiac perforation (DCP) with active‐fixation small‐diameter ICD leads has recently been reported, especially with regard to the St. Jude Riata lead (St. Jude Medical, Sylmar, CA, USA). Few data on the risk of DCP in small versus standard‐diameter leads implanted in a single high‐volume center are available. Moreover, no data on the performances of St. Jude's new small‐diameter Durata lead are as yet available. The aim of this study was to assess the incidence of DCP in small versus standard‐diameter leads implanted in our center. Methods: Between January 2003 and October 2009, 437 small‐diameter leads (190 Medtronic Sprint Fidelis [Medtronic Inc., Minneapolis, MN, USA], 196 Riata, 51 Durata) and 421 standard‐diameter (>8 Fr) leads were implanted. Results: After a median follow‐up of 421 days seven of 858 (0.8%) patients experienced DCP. The incidence of DCP was higher in patients with small‐diameter leads than in those with standard‐diameter leads (1.6% vs 0%, P = 0.01). No cases of DCP occurred among 371 passive‐fixation leads versus 1.4% of events among active‐fixation leads (P = 0.02). The incidence of DCP was 2.5% in Riata, 1% in Sprint Fidelis, 0% in Durata, and 0% in standard‐diameter leads (P < 0.01 for Riata vs standard‐diameter leads). Conclusions: Small‐diameter active‐fixation ICD leads are at increased risk of DCP, a finding mostly due to the higher incidence of events in the Riata family. By contrast, passive‐fixation small‐diameter leads and standard‐diameter leads appear to be safe enough regarding the risk of DCP. Our preliminary data suggest that the new Durata lead is not associated with an increased risk of DCP. (PACE 2011; 34:475–483)     

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.     

Inadvertent Implantation of an ICD Lead in the Great Cardiac Vein

We report an implantable cardioverter defibrillator (ICD) implanted with a single lead inadvertently introduced in the great cardiac vein. No venous lesion was caused by the shocks and the position of the lead remained stable. This case emphasizes the usefulness of different fluoroscopic views during ICD implantation.     

Clinical Evaluation of a Prototype Passive Fixation Dual Chamber Single Pass Lead For Dual Chamber ICD Systems

Dual chamber ICD systems use two separate leads for sensing. We developed and tested a new prototype of a single pass dual chamber passive fixation lead for dual chamber ICDs. Methods and Results: The prototype was a modification of the Guidant CPI Endotak DSP lead. The additional sensing electrode for the right atrium consisted of a side-mounted porous atrial ring electrode (AR). Atrial signals were recorded from the lead in patients during normal sinus rhythm (NSR), atrial fibrillation (AFib), and/or atrial flutter (AFl) with the AR in stable contact with the atrial wall or floating. During NSR, with the AR in contact with the atrial wall, an average P wave amplitude of 7.2 ± 1.5 mV (mean ± SD, n = 12) was measured. After induction of AFib/AFl, the single amplitude decreased to 3.6 ± 1.5 mV (n = 8) during AFib and 3.4 ± 1.7 mV (n = 9) during AFl. Amplitudes dropped between 53% and 75% when the AR lost atrial wall contact. The atrial pacing threshold was 1.0 ± 0.4 V (n = 16) when the AR was in contact with the atrial wall. Conclusions: In future dual chamber ICDs the signals from a passive fixation single pass lead could be used for atrial sensing and pacing as long as the sensing electrode for the right atrium remains in contact with the atrial wall. This system might lead to a simpler, less invasive implantation of dual chamber ICD systems.     

Multiple ICD Discharges Associated with Lead Fracture Without Triggering of High Impedance Alert

The Sprint Fidelis^® lead has an increased incidence of lead fracture. The manufacturer has recommended programming alerts to preempt lead malfunction due to fracture. The current trigger for an alert is an increase in the right ventricular pacing impedance to greater than 1,000 Ω. Our patient suffered multiple inappropriate implantable cardioverter defibrillator therapies with stable impedance less than 1,000 Ω. This case of lead fracture would not have been detected with these programming alerts. Additional programming measures may detect lead fractures, including changing the lower detection for impedances, arranging for a percentage change in the impedance trend to trigger an alarm, or programming the device to warn if there is an increase in nonphysiologic short R-R interval counts.     

Incidence of ICD Lead Related Complications During Long-Term Follow-Up: Comparison of Epicardial and Endocardial Electrode Systems

The aim of this study was to evaluate the longterm stability of epicardial and endocardial lead systems for third-generation cardioverter defibrillators (ICDs) and to assess the usefulness of diagnostic tools. One hundred forty patients with 61 epicardial (43.6%) and 79 nonthoracotomy systems (56.4%) were followed for 2 5 ± 19 months. A total of 18 (12.9%) lead related complications were documented. Complications of epicardial systems were detected in 10 patients (16.4%) during a follow-up time of 36 ± 8 months: crinkling of patch electrodes in 6 patients (9.8%), insulation breakage of sensing electrodes in 2 patients (3.3%), and adapter defect in 2 patients (3.3%). Eight of the patients (10.1%) with transvenous-subcutaneous systems had lead related complications during a 13 ± 6 months follow-up: fracture of the subcutaneous patch lead in 2 patients (2.5%), dislodgment of the right ventricular lead in 2 patients (2.5%), dislodgment of the superior vena cava lead in 2 patients (2.5%), insulation breakage of sensing electrodes in 1 patient (1.3%), and connector defect in 1 patient (1.3%). There was no significant difference in the incidence of lead related complications between epicardial and endocardial systems (P > 0.05). Fractures, dislodgments, and crinklings were documented within the first 8 ± 5 months by regular chest X ray. Defects of insulation, adapter, or connector were detected 22 ± 10 months after implantation and were associated with delivery of multiple inappropriate ICD therapies. An operative lead revision was indicated for 4 epicardial (6.6%) and 6 endocardial (7.6%) lead systems. Conclusions: Endocardial lead systems offer a similar long-term stability as compared to epicardial had systems. Chest X ray is the most useful tool to detect lead fracture, dislodgment. and patch crinkling. Marker recordings or real-time electrograms have not been helpful in this series to identify patients with suspected lead defects prior to the experience of inappropriate ICD discharges.     

Prevention of inappropriate ICD shocks due to lead insulation failure by continuous monitoring and automatic alert

Patients with implantable cardioverter defibrillator lead insulation failures may present with oversensing and/or abnormal impedance. The Lead Integrity Alert (LIA) monitors right ventricular pace/sense leads using both continuous oversensing and daily impedance measurementd. Oversensing consists of isolated short R‐R intervals and nonsustained runs of short R‐R intervals. The LIA algorithm has been studied for Sprint Fidelis conductor fractures, but not for lead insulation failures. We report on a patient with a failed St. Jude Riata? ST lead (St. Jude Medical, St. Paul, MN, USA) connected to a Medtronic Virtuoso DR (Medtronic Inc., Minneapolis, MN, USA) with the LIA. Oversensing triggered the LIA, while the impedance trend was normal. (PACE 2012; 35:e150–e153)     

Inappropriate ICD Discharges Due to Noise Oversensing as the First Sign of Repetitive Perforations of the Right Ventricular Lead

Acute lead perforation is one of the major complications associated with implantable cardioverter defibrillator (ICD) implantation. We describe a case with repetitive inappropriate ICD discharges due to noise oversensing as the first sign of lead perforation.