Pablo B. Nery

Device‐Related Infection Among Patients With Pacemakers and Implantable Defibrillators: Incidence, Risk Factors, and Consequences

Risk Factors and Complications of Pacemaker and ICD Infection. Background: Device‐related infection is a major limitation of device therapy for cardiac arrhythmia.

Clinical Predictors of Fidelis Lead Failure Report From the Canadian Heart Rhythm Society Device Committee

Background— Approximately 268 000 Fidelis leads were implanted worldwide until distribution was suspended because of a high rate of early failure. Careful analyses of predictors of increased lead failure hazard are required to help direct future lead design and also to inform decision making on lead replacement. We sought to perform a comprehensive analysis of all potential predictors in a multicenter study. Methods and Results— A total of 3169 Sprint Fidelis leads were implanted in 11 centers with a total of 251 failures. Lead failure rates at 3, 4, and 5 years were 5.3%, 10.6%, and 16.8%, respectively. The rate of lead failure continues to accelerate (P<0.001). There were 4 independent predictors of failure: center, sex, access vein, and previous lead failure. Women had a higher hazard of failure (hazard ratio 1.51; 95% confidence interval, 1.14–2.04; P=0.005). Both axillary and subclavian access increased the hazard of failure (P=0.007); hazard ratio for axillary was 1.94, (95% confidence interval, 1.23–3.04) and for subclavian 1.63 (95% confidence interval, 1.08–2.46). Previous lead failure increased the hazard of a subsequent Fidelis failure with a hazard ratio of 3.12 (95% confidence interval, 1.80–5.41; P<0.001). Conclusions— The rate of Fidelis failure continues to increase over time, with failures approaching 17% at 5 years. Women, patients with leads inserted via the subclavian or axillary vein, and those with a previous lead fracture were at greatest risk of Fidelis failure. Our data suggest that Fidelis replacement should be strongly considered at the time of generator replacement.Background— Approximately 268 000 Fidelis leads were implanted worldwide until distribution was suspended because of a high rate of early failure. Careful analyses of predictors of increased lead failure hazard are required to help direct future lead design and also to inform decision making on lead replacement. We sought to perform a comprehensive analysis of all potential predictors in a multicenter study. Methods and Results— A total of 3169 Sprint Fidelis leads were implanted in 11 centers with a total of 251 failures. Lead failure rates at 3, 4, and 5 years were 5.3%, 10.6%, and 16.8%, respectively. The rate of lead failure continues to accelerate ( P <0.001). There were 4 independent predictors of failure: center, sex, access vein, and previous lead failure. Women had a higher hazard of failure (hazard ratio 1.51; 95% confidence interval, 1.14–2.04; P =0.005). Both axillary and subclavian access increased the hazard of failure ( P =0.007); hazard ratio for axillary was 1.94, (95% confidence interval, 1.23–3.04) and for subclavian 1.63 (95% confidence interval, 1.08–2.46). Previous lead failure increased the hazard of a subsequent Fidelis failure with a hazard ratio of 3.12 (95% confidence interval, 1.80–5.41; P <0.001). Conclusions— The rate of Fidelis failure continues to increase over time, with failures approaching 17% at 5 years. Women, patients with leads inserted via the subclavian or axillary vein, and those with a previous lead fracture were at greatest risk of Fidelis failure. Our data suggest that Fidelis replacement should be strongly considered at the time of generator replacement. # Clinical Perspective {#article-title-32}

Corticosteroid therapy for cardiac sarcoidosis: a systematic review.

BACKGROUND There are no published clinical consensus guidelines or systematic evaluation supporting the use of corticosteroids for the treatment of cardiac sarcoidosis. The purpose of this study was to systematically review the published data on corticosteroid treatment of cardiac sarcoidosis. METHODS Studies were identified from MEDLINE, EMBASE, Cochrane Controlled Trials Register, Cochrane Database of Systematic Reviews, and National Institutes of Health Clinical Trials.gov database. The quality of included articles was rated using Scottish Intercollegiate Guidelines Network 50. Outcomes examined were atrioventricular (AV) conduction, left ventricular function, ventricular arrhythmias, and mortality. RESULTS A total of 1491 references were retrieved and 10 publications met the inclusion criteria. There were no randomized trials and all publications were of poor to fair quality. In the 10 reports, 257 patients received corticosteroids and 42 patients did not. There were 57 patients with AV conduction disease treated with corticosteroids, with 27/57 (47.4%) improving. In contrast, 16 patients were not treated with corticosteroids and 0/16 improved. Four publications reported on left ventricular function recovery, 2 reported on ventricular arrhythmia burden, and 9 reported on mortality. However, the data quality were too limited to draw conclusions for any of these outcomes. CONCLUSIONS Our systematic review identified 10 publications reporting outcomes after corticosteroid therapy. The best data relates to AV conduction recovery and corticosteroids appeared to be beneficial. It is not possible to draw clear conclusions about the utility of corticosteroids for the other outcomes. There is a clear need for large multicentre prospective registries and trials in this patient population.

The role of F(18)-fluorodeoxyglucose positron emission tomography in guiding diagnosis and management in patients with known or suspected cardiac sarcoidosis.

Cardiac sarcoidosis (CS) has gained significant interest in recent years with the emergence of advanced imaging modalities such as MRI and F18-fluorodeoxyglucose-positron emission tomography (FDG-PET) as modalities to aid in the diagnosis of this condition. CS remains a difficult condition to diagnose, particularly in cases of isolated cardiac involvement and it can present with a broad spectrum of clinical syndromes. Furthermore, the appropriate management of these patients remains controversial. FDG-PET has a potential role not only in diagnosis of CS but also in directing further therapies, facilitating the decision to start immunosuppression and monitoring the response to it. In this article, we discuss when to consider FDG-PET, outline the current optimal patient preparation and scanning protocols and then, using case examples, discuss the use of FDG-PET in follow-up of patients with known or suspected CS. We also outline how PET can influence management decisions in these patients.

Is There an Association Between Clinical Presentation and the Location and Extent of Myocardial Involvement of Cardiac Sarcoidosis as Assessed by 18F- Fluorodoexyglucose Positron Emission Tomography?

Background— Positron emission tomography using 18F-Fluorodeoxyglucose (FDG) is an emerging modality for diagnosis of cardiac sarcoidosis (CS). We compared the location and degree of FDG uptake in CS patients presenting with either advanced atrioventricular block (AVB) or ventricular tachycardia (VT). Methods and Results— We included consecutive patients who presented with either AVB or VT with a diagnosis of CS. A cohort of patients with clinically silent CS was included as controls. FDG activity was quantified as standardized uptake values (SUV) and both the overall mean left ventricular (LV) SUV as well as the Maximum Mean Segmental SUV was recorded for each patient. Receiver operator characteristic (ROC) analysis was performed to identify cutoff SUV values that best identified patients with VT. A total of 27 patients with CS were included (13 females; mean age, 56±8 years; 8 VT, 12 AVB, and 7 controls). Both mean LV SUV and Max SUV in CS patients presenting with VT were significantly higher compared with those with AVB (mean SUV: VT median 5.33, range 4.7–9.35 versus AVB median 2.48, range 0.86–8.59, P=0.016; max SUV: VT median 11.07, range 9.24–14.4 versus AVB median 5.63, range 3.42–15.71, P=0.005) and compared with controls. There was no significant difference in SUV values between AVB patients and controls. ROC analysis for identification of patients with VT showed AUCs of 0.93 and 0.895 for a mean LV SUV of >3.42 and a max SUV >8.56, respectively (P<0.001). Conclusions— CS patients with VT displayed significantly higher FDG uptake when compared with those with AVB and asymptomatic controls. Further prospective studies are required to evaluate this finding.

Atrioesophageal Fistula in the Era of Atrial Fibrillation Ablation: A Review

The purpose of this review is to understand the epidemiology, clinical features, etiopathogenesis, and management of atrioesophageal fistula (AEF) after atrial fibrillation (AF) ablation. The incidence of AEF after AF ablation is 0.015%-0.04%. The principal clinical features include fever, dysphagia, upper gastrointestinal bleeding, sepsis, and embolic strokes. The close proximity of the esophagus to the posterior left atrial wall is responsible for esophageal injury during ablation. Prophylactic proton pump inhibitors, esophageal temperature monitoring, visualization of the esophagus during catheter ablation, esophageal protection devices, and avoidance of energy delivery in close proximity to the esophagus play an important role in preventing esophageal injury. Early surgical repair or esophageal stenting are the mainstay of treatment. Eliminating esophageal injury during AF ablation is of utmost importance in preventing AEF. A high index of suspicion and early intervention is necessary to prevent fatal outcomes.

Failure rate of the Riata lead under advisory: A report from the CHRS Device Committee

BACKGROUND A unique form of lead failure has been described in the Riata (8-F) and Riata ST (7-F) silicone defibrillation lead degradation of the outer insulation, resulting in the externalization of conductor cables. OBJECTIVE To assess rates of lead revision due to lead failure in Riata leads affected by the Riata advisory. METHODS Nineteen implantable cardioverter-defibrillator implant and follow-up centers were surveyed. RESULTS As of March 1, 2012, there were 5043 known affected leads implanted in Canada. Data on 4358 (86.4%) leads were obtained; 65.3% of these were Riata (8-F) and 32.4% were Riata ST (7-F) leads. The median time from implant to last follow-up was 5 years. Electrical abnormalities were reported in 4.6% of the affected leads; 8.0% of these were found to have concomitant radiographic evidence of externalization. The rate of electrical failure was higher in the 8-F (5.2%) vs 7-F (3.3%) leads (P = .007). Oversensing with or without inappropriate shocks was reported in 39.8% of the leads with confirmed failure. Abnormally high or low impedance values (29.9%) and elevated pacing capture thresholds (43.8%) were frequently reported. One death (0.5%) attributed to lead failure was reported. Among the leads that were replaced, 21% were extracted. Two major complications (1.0%) were attributed to extraction of these leads. CONCLUSIONS The overall rate of lead failure in the Riata (8-F) and Riata ST (7-F) leads is higher than previously reported by using passive surveillance data. The impact of recent advisories related to these leads is not yet apparent.

Cardiac resynchronization therapy in patients with left ventricular systolic dysfunction and right bundle branch block: A systematic review

BACKGROUND Whether patients with right bundle branch block (RBBB) benefit from cardiac resynchronization therapy (CRT) is unclear. OBJECTIVE The purpose of this study was to systematically review the published data from randomized clinical trials of CRT on the outcomes in patients with baseline RBBB. METHODS Randomized controlled trials of CRT in heart failure and left ventricular systolic dysfunction were identified from MEDLINE (1950-2010), EMBASE (1980-2010, week 45), Cochrane Controlled Trials Register (2009), Cochrane Database of Systematic Reviews, National Institutes of Health Clinical Trials.gov database. RESULTS A total of 112 references were retrieved. Four publications from five studies reported data on patients with RBBB and were included in this investigation, with 259 patients randomized to CRT and 226 randomized to non-CRT. None of the available data showed more favorable outcomes (soft or hard) in patients with CRT. CONCLUSION None of the available data showed more favorable outcomes with CRT in patients with RBBB. A meta-analysis of RBBB patients from the major CRT trials is urgently needed. Results of the meta-analysis can direct further research, perhaps indicating a need for randomized trials in RBBB. Physicians and patients should be aware of the likely reduced benefit form CRT in patients with RBBB, and this should be factored into decision making. However, until more data are available it is too early to change guidelines.

Atrioventricular Block as the Initial Manifestation of Cardiac Sarcoidosis in Middle-Aged Adults

Atrioventricular block (AVB) can be caused by several conditions, including cardiac sarcoidosis (CS). The prevalence of CS causing this presentation in a North American population has not been investigated and was the purpose of this study.

Psychological Adjustment in ICD Patients Living With Advisory Fidelis Leads

Psychological Adjustment and Fidelis ICD Leads. Introduction: Implantable cardioverter defibrillators (ICD) advisory notices present treatment dilemmas for physicians and patients. On one side, the risk of device malfunction and the likely severity of clinical sequelae have to be estimated. This estimate has to be weighed against the risks of surgery to replace the advisory component. It is unclear whether there is important psychological morbidity associated with living with an ICD under advisory and whether this should be factored into decision making. The study had 2 objectives: (1) to examine whether there is adverse psychological adjustment when an ICD is under advisory, and (2) to assess the psychological sequel of advisory ICD component malfunction.