Melanie Maytin

Superior vena cava defibrillator coils make transvenous lead extraction more challenging and riskier

To the Editor: Studies have demonstrated equivalent defibrillation efficacy and all-cause mortality in patients with single and dual coil implantable cardioverter-defibrillator (ICD) leads ([1,2][1]). Despite this equivalency, the vast majority of implanted ICD leads are dual coil ([3][2]). The

Multicenter Experience With Extraction of the Sprint Fidelis Implantable Cardioverter-Defibrillator Lead

OBJECTIVES This study was undertaken to determine the safety and feasibility of extraction of the Sprint Fidelis (Medtronic, Minneapolis, Minnesota) lead. BACKGROUND The reported failure rate of the Sprint Fidelis defibrillator lead has increased to a range greater than initially appreciated with emerging evidence of an accelerating rate of fracture. At present, consensus guidelines continue to recommend against prophylactic extraction of the lead, citing major complication rates between 1.4% and 7.3%. However, data regarding the safety and feasibility of extraction of small-diameter, backfilled implantable cardioverter-defibrillator leads such as the Sprint Fidelis are limited. METHODS We performed a retrospective cohort study of consecutive patients undergoing extraction of Sprint Fidelis (models 6930, 6931, 6948, 6949) leads at 5 high-volume centers. Patient characteristics, indications for extraction, and use of countertraction sheath (CTS) assistance are reported. The risk of major and minor complications was determined. A multivariable logistic regression model was developed to predict factors associated with the use of CTS assistance. RESULTS Between May 2005 and August 2009, 349 Sprint Fidelis leads were extracted from 348 patients. All leads were removed completely. The average duration of the implanted lead was 27.5 months (range 0.03 to 58.8 months). Approximately one-half of the extracted leads were fractured (49.4%), and 26.5% were extracted prophylactically. The other major indication for extraction was infection (22.8%). Extraction was achieved with simple traction in 49.4% leads; CTS assistance was required in 174 cases (50.6%). In multivariable models, length of time since implantation was directly related to the need for CTS assistance (odds ratio per month since implantation: 1.035; 95% confidence interval: 1.010 to 1.061; p=0.006). There were no major procedural complications or deaths. CONCLUSIONS Extraction of the Sprint Fidelis lead can be performed safely by experienced operators at high-volume centers with a complication rate lower than that reported for older generation leads. However, leads with longer implant durations are associated with the use of CTS assistance. Recommendations regarding prophylactic Sprint Fidelis lead extraction may warrant reconsideration.

Pressure Overload–Induced Myocardial Hypertrophy in Mice Does Not Require gp91phox

Background—Reactive oxygen species (ROS) may mediate pressure overload–induced myocardial hypertrophy. NADPH oxidase may be involved in this process, because its expression and activity are upregulated by pressure overload and because myocardial hypertrophy caused by a subpressor infusion of angiotensin is attenuated in mice deficient in the gp91phox catalytic subunit of NADPH oxidase. Methods and Results—To test the role of NADPH oxidase–dependent ROS in mediating pressure overload–induced myocardial hypertrophy, we subjected transgenic mice lacking gp91phox to chronic pressure overload caused by constriction of the ascending aorta. Contrary to our hypothesis, neither myocardial hypertrophy nor NADPH-dependent superoxide generation was decreased in gp91phox-deficient mice after aortic constriction. Aortic constriction caused an exaggerated increase in p22phox and p47phox mRNA in gp91phox-deficient mice. Conclusions—These results indicate that gp91phox is not necessary for pressure overload–induced hypertrophy in the mouse and suggest the involvement of another source of ROS, possibly an NADPH oxidase that does not require the gp91phox subunit.

Lead Extraction Is Preferred for Lead Revisions and System Upgrades: When Less Is More

Cardiovascular implantable electronic device (CIED) use has increased exponentially during the past decade,1,–,3 with >4.5 million active devices and >1 million new leads implanted annually.4,5 With expanded CIED use and indications for device therapy, observed complications have increased in parallel.6,–,14 The occurrence of more frequent device system revisions for complications,6,–,8 system upgrades,15,–,17 and/or lead malfunction9,–,13 and longer patient life expectancies have mandated a paradigm shift toward premeditated lead management strategies from implant to removal or replacement. Consequently, clinicians increasingly are faced with the challenging choice of extraction or abandonment of sterile, superfluous leads. The decision is difficult and highly controversial,4,18,–,26 with limited rigorous evidence and passionate arguments on either side. Response by Henrikson on p 424 We contend that although decisions regarding extraction in these situations must be made on a case-by-case basis after considering multiple patient- and physician-related variables, lead extraction should be the preferred management strategy for lead revisions and system upgrades. Randomized, controlled trials of extraction versus abandonment are lacking, but the available evidence from observational, cohort, and registry studies supports the contention that the potential future benefit of lead extraction outweighs the risks of lead abandonment and that lead abandonment should be viewed as a “palliative procedure” that “just postpones the inevitable future lead extraction.”27 In patients with venous occlusion undergoing the addition of a lead with plans to preserve the existing leads (eg, VVI to DDD implantable cardioverter defibrillator, or DDD implantable cardioverter defibrillator upgrade to BiV implantable cardioverter defibrillator), venoplasty, when possible, is the preferred approach. In many such patients, the venous obstruction is short in length and …

Long-term mortality after transvenous lead extraction.

Background— The number of cardiovascular implantable electronic devices has increased progressively and has led to an increased need for transvenous lead extraction (TLE). Multiple reports of TLE procedural outcomes exist; however, data regarding postprocedural and long-term mortality are limited. Methods and Results— We performed a retrospective study of consecutive patients undergoing TLE at a single, high-volume center. Patient characteristics, indications, and outcomes were analyzed. A multivariable Cox regression model was developed to identify factors associated with mortality. Between January 2000 and December 2010, 985 patients underwent 1043 TLE procedures. The cohort was 68% male, with a mean age of 63 years (range, 15–95 years) and a left ventricular ejection fraction of 40±17%. Indications included systemic infection (18%), pocket infection (32%), lead malfunction (30%), and other (device upgrade, venous occlusion, and advisory leads; 20%). There were no procedure-related deaths. The mean follow-up was 3.7 years (range, 0.1–11.3 years). Kaplan–Meier analysis demonstrated a cumulative mortality of 2.1% at 30 days, 4.2% at 3 months, 8.4% at 1 year, and 46.8% at 10 years. In multivariable analysis, systemic infection (hazard ratio [HR], 3.52; 95% CI, 1.95–6.38; P<0.0001), local infection (HR, 2.70; 95% CI, 1.55–4.67; P=0.0004), device system upgrade (HR, 2.14; 95% CI, 1.07–4.25; P=0.03; indication compared with a reference group of extraction for lead malfunction), diabetes mellitus (HR, 1.71; 95% CI, 1.25–2.35; P=0.0009), increasing age (HR, 1.05; 95% CI, 1.04–1.07; P<0.0001), and serum creatinine (HR, 1.16; 95% CI, 1.01–1.35; P=0.04) were significant correlates of increased mortality risk. Conclusions— Although TLE procedural mortality is exceedingly low at high-volume centers, postprocedural and long-term mortality remain high in certain patient populations, such as elderly patients and those undergoing TLE for infectious indications and device system upgrade. Information regarding TLE long-term outcomes may help guide cardiovascular implantable electronic device and lead management.

Ventricular Tachycardia in Cardiac Sarcoidosis: Characterization of Ventricular Substrate and Outcomes of Catheter Ablation

Background—Cardiac sarcoid–related ventricular tachycardia (VT) is a rare disorder; the underlying substrate and response to ablation are poorly understood. We sought to examine the ventricular substrate and outcomes of catheter ablation in this population. Methods and Results—Of 435 patients with nonischemic cardiomyopathy referred for VT ablation, 21 patients (5%) had cardiac sarcoidosis. Multiple inducible VTs were observed with mechanism consistent with scar-mediated re-entry in all VTs. Voltage maps showed widespread and confluent right ventricular scarring. Left ventricular scarring was patchy with a predilection for the basal septum, anterior wall, and perivalvular regions. Epicardial right ventricular scar overlay and exceeded the region of corresponding endocardial scar. After ≥1 procedures, ablation abolished ≥1 inducible VT in 90% and eliminated VT storm in 78% of patients; however, multiple residual VTs remained inducible. Failure to abolish all inducible VTs was because of septal intramural circuits or extensive right ventricular scarring. Multiple procedure VT-free survival was 37% at 1 year, but VT control was achievable in the majority of patients with fewer antiarrhythmic drugs compared with preablation (2.1±0.8 versus 1.1±0.8; P<0.001). Conclusions—Patients with cardiac sarcoidosis and VT exhibit ventricular substrate characterized by confluent right ventricular scarring and patchy left ventricular scarring capable of sustaining a large number of re-entrant circuits. Catheter ablation is effective in terminating VT storm and eliminating ≥1 inducible VT in the majority of patients, but recurrences are common. Ablation in conjunction with antiarrhythmic drugs can help palliate VT in this high-risk population.

Long-Term Mortality Following Transvenous Lead Extraction

Background— The number of cardiovascular implantable electronic devices has increased progressively and has led to an increased need for transvenous lead extraction (TLE). Multiple reports of TLE procedural outcomes exist; however, data regarding postprocedural and long-term mortality are limited. Methods and Results— We performed a retrospective study of consecutive patients undergoing TLE at a single, high-volume center. Patient characteristics, indications, and outcomes were analyzed. A multivariable Cox regression model was developed to identify factors associated with mortality. Between January 2000 and December 2010, 985 patients underwent 1043 TLE procedures. The cohort was 68% male, with a mean age of 63 years (range, 15–95 years) and a left ventricular ejection fraction of 40±17%. Indications included systemic infection (18%), pocket infection (32%), lead malfunction (30%), and other (device upgrade, venous occlusion, and advisory leads; 20%). There were no procedure-related deaths. The mean follow-up was 3.7 years (range, 0.1–11.3 years). Kaplan–Meier analysis demonstrated a cumulative mortality of 2.1% at 30 days, 4.2% at 3 months, 8.4% at 1 year, and 46.8% at 10 years. In multivariable analysis, systemic infection (hazard ratio [HR], 3.52; 95% CI, 1.95–6.38; P<0.0001), local infection (HR, 2.70; 95% CI, 1.55–4.67; P=0.0004), device system upgrade (HR, 2.14; 95% CI, 1.07–4.25; P=0.03; indication compared with a reference group of extraction for lead malfunction), diabetes mellitus (HR, 1.71; 95% CI, 1.25–2.35; P=0.0009), increasing age (HR, 1.05; 95% CI, 1.04–1.07; P<0.0001), and serum creatinine (HR, 1.16; 95% CI, 1.01–1.35; P=0.04) were significant correlates of increased mortality risk. Conclusions— Although TLE procedural mortality is exceedingly low at high-volume centers, postprocedural and long-term mortality remain high in certain patient populations, such as elderly patients and those undergoing TLE for infectious indications and device system upgrade. Information regarding TLE long-term outcomes may help guide cardiovascular implantable electronic device and lead management.

The challenges of transvenous lead extraction

Transvenous lead extraction (TLE) has undergone an explosive evolution since its inception as a rudimentary skill with limited technology and therapeutic options. Early techniques involved simple manual traction that frequently proved ineffective for chronically implanted leads and carried a significant risk of myocardial avulsion, tamponade, and death.1 2 The significant morbidity and mortality associated with these early extraction techniques limited their application to life threatening situations such as infection and sepsis. The past 30 years have witnessed significant advances in lead extraction technology resulting in safer and more efficacious techniques and tools, providing the skilled extractor with a well equipped armamentarium. With the development of the discipline, we have witnessed a growth in the community of TLE experts coincident with a pronounced decline in the incidence of procedure related morbidity and mortality, with more recent registries at high volume centres reporting high success rates with exceedingly low complication rates (figure 1).3–6 Future developments in lead extraction are likely to focus on new tools that will allow us to provide comprehensive device management, alternative systems for extraction training, and the design of new leads conceived to facilitate future extraction. Figure 1 Success, morbidity and mortality in large series. Graphic representation of complete success as a function of time, represented by black columns. Secondary y axis represents percentage morbidity (orange) and mortality (red). Timeline of extraction techniques and tools commensurate with reported trials is at the top of the figure. Values below the graph represent the number of leads (N) extracted in each study. Composite major complication (MC) and mortality (M) rate was calculated. Only studies with ≥50 leads extracted and data regarding mortality and major complications were included. The challenges and risks of TLE are principally related to the bodys foreign body response to a cardiovascular implantable electronic device (CIED). This …

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.

Multicenter experience with extraction of the Riata/Riata ST ICD lead

BACKGROUND In November 2011, the Food and Drug Administration issued a class I recall of Riata and Riata ST implantable cardioverter-defibrillator leads. Management recommendations regarding the recall have remained controversial. OBJECTIVE Data regarding the safety and feasibility of extraction of Riata implantable cardioverter-defibrillator leads are limited. METHODS We performed a retrospective study of patients undergoing extraction of Riata/Riata ST leads at 11 centers. RESULTS Between July 2003 and April 2013, 577 Riata/Riata ST leads were extracted from 577 patients (Riata 467, [84%]; Riata ST 89, [16%]). Complete procedural success achieved in 99.1%. The cohort was 78% men, with a mean age of 60 years and a mean left ventricular ejection fraction of 34% ± 14%. The mean implant duration was 44.7 months (range 0-124.6 months). The majority of leads extracted were for infection (305 [53.0%]) and 220 (35.7%) for lead malfunction. Evaluation for lead integrity was performed in 295 cases. Of these, 34.9% were found to have externalized cables. Implant duration was significantly longer in leads with externalized cables (P < .0001). No difference in lead integrity was noted between Riata and Riata ST leads (11.7% vs. 17.7% failure; P = .23). Among leads in which cable externalization was noted, laser sheaths were used more frequently (P = .01). Major complications included 3 superior vena cava/right ventricular perforations requiring surgical intervention with 1 death 12 days after the procedure and 1 pericardial effusion requiring percutaneous drainage (0.87%). CONCLUSION Extraction of the Riata/Riata ST leads can be challenging, and leads with externalized cables may require specific extraction techniques. Extraction of the Riata/Riata ST leads can be performed safely by experienced operators at high-volume centers with a complication rate comparable to published data.