Manufacturer change and risk of system-related complications after implantable cardioverter defibrillator replacement: physicians' survey and data from the Detect Long-term Complications After Implantable Cardioverter Defibrillator Replacement Registry.

AIMS: Some barriers seem to exist in changing implantable cardioverter defibrillator (ICD) manufacturer at the time of device replacement. We sought to understand the obstacles to changing ICD manufacturer within the cohort of patients enrolled in the Detect Long-term Complications After ICD Replacement Registry. METHODS: We analyzed 784 consecutive ICD/cardiac resynchronization therapy defibrillator (CRT-D) device replacements within a 1.5-year time-frame in 36 Italian centers to evaluate potential factors associated with changing manufacturers and system-related complications. RESULTS: Manufacturer change occurred in 191 patients (24%): 72/211 single-chamber ICDs (34%), 52/210 dual-chamber ICDs (25%) and 67/363 CRT-D (18%, P < 0.0001 vs. single-chamber). Replacement-only procedures were associated with a lower rate of manufacturer change than upgrading procedures (23 vs. 32%, P = 0.02). In the single-chamber/dual-chamber cohort, the only variables associated with manufacturer change were the number of available manufacturers (OR = 1.9; P < 0.0001) and an upgrade procedure (OR = 1.7; P = 0.035), whereas the center volume was associated with maintenance of the same manufacturer (OR = 0.5; P = 0.0172). In the CRT-D group, the number of available manufacturers [OR = 2.9; P < 0.0001, service life below the median value (OR = 2.5; P = 0.0026)], and physiological design (OR = 8.4; P = 0.0048) were associated with manufacturer change. At 6-month follow-up, 17 patients (2.2%) experienced a system complication that was lead-related in all cases; upgrade procedure was the only predictor (hazard ratio = 6.7) of complications. CONCLUSION: At the time of ICD replacement, a manufacturer change occurred in 24% of patients and it was less likely in CRT-D devices, which are equipped with more specific technology and less frequently require the addition of features. System-related complications are strongly associated to upgrade procedures rather than to manufacturer change.

Inflammation and C-reactive protein in atrial fibrillation: cause or effect?

Atrial fibrillation is associated with substantial morbidity and mortality rates. The incompletely understood pathogenesis of this cardiac dysrhythmia makes it difficult to improve approaches to primary and secondary prevention. Evidence has accumulated in regard to a relationship between inflammation and atrial fibrillation. Investigators have correlated the dysrhythmia with myocarditis, pericardiotomy, and C-reactive protein levels, suggesting that inflammation causes atrial fibrillation or participates in its onset and continuation. Conversely, other investigators suggest that atrial fibrillation induces an inflammatory response. In this review, we summarize and critically discuss the nature and clinical role of inflammation and C-reactive protein in atrial fibrillation.

Cardiovascular implantable electronic device infection: delayed vs standard FDG PET-CT imaging.

BACKGROUND: Positron emission tomography-computed tomography (PET-CT) with (18)F-fluorodeoxyglucose (FDG) has emerged as a rapidly evolving diagnostic tool for infectious diseases. However, the optimal imaging time in this clinical setting is not clear yet. The aim of this study is to investigate whether delayed (3 hours) FDG PET-CT could increase the diagnostic accuracy of this technique compared to standard (1 hour) imaging in the detection of septic foci involving the pocket and/or pacing leads in patients with suspected cardiovascular implantable electronic device (CIED) infection scheduled for device removal. METHODS AND RESULTS: Twenty-seven patients underwent standard and delayed imaging. PET-CT results were compared to bacteriological cultures after CIED removal. Fifteen controls free of infection underwent PET-CT imaging as part of investigation of malignancy. The diagnostic accuracy of delayed imaging was significantly higher than 1-hour scan for lead infection (70% vs 51%, P = .024). No significant difference was found between standard and delayed diagnostic accuracy for pocket or device infection. Semi-quantitative analysis showed that mean pocket and lead target-to-background ratio were significantly higher on delayed compared to standard imaging (3.7 ± 1.9 vs 1.6 ± 1.1, P = .0002; 3.0 ± 1.3 vs 0.7 ± 1.0, P = .01). CONCLUSIONS: Delayed FDG PET-CT imaging should be considered at least in patients with negative 1-hour scan and founded suspicion of pacing lead infection.

A Challenging Case Of Ventricular Arrhythmia In A Patient With Myocarditis: ICD Yes/No After Ablation.

In patients with myocarditis, early diagnosis and appropriate therapy are mandatory, as well as close clinical follow-up with particular regard to progression of disease and ventricular arrhythmia recurrences. The management of ventricular arrhythmias should follow current guidelines for ICD implantation, but new therapeutic options could be evaluated in these patients, such as combined epicardial/endocardial ablation and external wearable defibrillator. Particularly, depressed left ventricular ejection fraction (LVEF) represents the only risk marker for sudden cardiac death currently used in myocarditis, although the use of a single risk factor has limited utility. On this regard, combined analysis of myocardial tissue structure by cardiac magnetic resonance (CMR) and endomyocardial biopsy, in association with resting cardiac systolic function, could improve predictive accuracy for SCD in patients with myocarditis.

Reversible atrial gap junction remodeling during hypoxia/reoxygenation and ischemia: a possible arrhythmogenic substrate for atrial fibrillation.

Alteration of cardiomyocyte gap-junctions and component connexins (Cx) has been suggested to contribute to the development of atrial fibrillation (AF), including postoperative AF. We tested different possible stimuli, such as hypoxia and ischemia, influencing Cx43 and Cx40 expression and distribution in cultured atrial cells (HL-1) and reversibility of these processes after reoxygenation. Western-blot analysis and immunostaining using anti-Cx43, anti-Cx40 and anti-zonula occludens polyclonal antibodies were performed. HL-1 cells exposed to hypoxia for 24 and 48 h showed a reduction of Cx43 protein levels by 75% and 90% respectively (p < 0.001). During reoxygenation following 24 h of hypoxia, Cx43 levels increased to reach the basal level within 48 h, while they remained at low level during reoxygenation following 48 h of hypoxia. Furthermore, atrial cardiomyocytes subjected to simulated ischemia (SI) were incubated in normoxic and hypoxic conditions for 3, 6, 9, 12 h. Atrial cardiomyocytes subjected to SI in addition to normoxia showed a progressive reduction of Cx43 levels beginning from 3 h. During SI and hypoxia, atrial Cx43 levels showed an initial decrease after 3 h with a subsequent rescue beginning from 6 h of exposure (p = 0.001). Hypoxia and ischemia per se downregulate Cx43 protein expression in atrial cardiomyocytes, but protein downregulation is reversible, depending on hypoxia duration and the association of the two triggers. These alterations characterize several conditions and might contribute to the generation of an arrhythmogenic substrate leading to AF onset and/or maintenance.

Safety and effectiveness of transvenous lead extraction in octogenarians.

INTRODUCTION: As the population ages, the number of elderly patients with implantable cardiac devices referred for transvenous lead extraction will dramatically increase in Western countries. The safety and effectiveness of lead extraction in elderly patients has not been well evaluated. We report the safety and effectiveness of transvenous lead extraction in octogenarians. METHODS AND RESULTS: From January 2005 to January 2011, we reviewed data from consecutive patients ≥ 80 years referred to our institutions for transvenous lead extraction because of cardiac device infection or lead malfunction. Clinical characteristics, procedural features, and periprocedural major and minor complications were compared between octogenarians and younger patients. Out of 849 patients undergoing lead extraction in the participating institutions during the study period, 150 (18%) patients were octogenarians (mean age 84 years; range 80-96; 64% males). A significantly higher percentage of octogenarians presented with chronic renal failure (55% vs 26%; P < 0.001), history of malignancy (22% vs 6%; P < 0.001), and chronic obstructive pulmonary disease (46% vs 19%; P < 0.001). Complete lead extraction rates were similar in the 2 age groups (97% in octogenarians vs 96% in patients <80 years; P = 0.39). Periprocedural death occurred in 2 (1.3%) patients ≥80 years and in 5 (0.72%) patients <80 years (P = 0.45 for comparison). No differences in terms of other periprocedural major and minor complications were found between the 2 age groups. CONCLUSION: Despite presenting with a significantly higher rate of comorbidities, transvenous lead extraction can be performed safely and successfully in octogenarians.

Imaging of scar in patients with ventricular arrhythmias of right ventricular origin: cardiac magnetic resonance versus electroanatomic mapping.

INTRODUCTION: Assessment of late gadolinium enhancement (LGE) at cardiac magnetic resonance is often used to detect scar in patients with arrhythmias of right ventricular (RV) origin. Recently, electroanatomic mapping (EAM) has been shown to reliably detect scars corresponding to different cardiomyopathic substrates. We compared LGE with EAM for the detection of scar in patients with arrhythmias of RV origin. METHODS AND RESULTS: Thirty-one patients with RV arrhythmias and biopsy-proven structural heart disease (18 ARVC and 13 myocarditis), and 5 with idiopathic RV outflow tract arrhythmias underwent LGE analysis and EAM with scar validation through EAM-guided endomyocardial biopsy. EAM scars were present in 23 (64%) patients (all with structural heart disease), whereas LGE was present only in 12 (33%). In 2 cases, EAM provided a false-positive diagnosis of a small scar in the basal perivalvular area. LGE correctly diagnosed EAM scar in 48% of patients, resulting in high positive (92%) but low negative (50%) predictive values. The distribution of LGE was significantly associated with the distribution of EAM scars (P < 0.001 in the free wall, P = 0.003 in the outflow tract, and P = 0.023 in the posterior/inferior wall). Presence of LGE reflected a higher extension of EAM scars (34.4 ± 16.5% vs 7.9 ± 10.1% of the RV area, P < 0.001). At receiver operating characteristic (ROC) analysis, an extension of scar ≥20% of the RV area was the best cut-off value to detect LGE (sensitivity 83%, specificity 92%). Of note, LGE missed 10 of 11 (91%) patients with EAM scars <20% of RV area. CONCLUSIONS: LGE is significantly less sensitive than EAM in identifying RV cardiomyopathic substrates. Absence of LGE does not rule out the presence of small scars, and EAM with biopsy should be considered to increase the diagnostic yield.