Predictors of ventricular ablation's success: Viability, innervation, or mismatch?

AIMS: Sympathetic dys-innervation may play an important role in the development of post-ischemic ventricular arrhythmias (VA). Aim of this study was to prove that perfusion/innervation mismatch (PIM) evaluated by SPECT can identify areas of local abnormal ventricular activities (LAVA) on electroanatomic mapping (EAM). METHODS: Sixteen patients referred to post-ischemic VA catheter ablation underwent pre-procedural and 1-month post-ablation 123I-MIBG/99mTc-tetrofosmin rest SPECT myocardial imaging. PIM was defined according to the segmental distributions of 99mTc-tetrofosmin and 123I-MIBG. A 17-segment LV analysis was used for either SPECT or LV EAM voltage map. All patients were followed up clinically for at least 1 year. RESULTS: Before ablation, the mean voltage in the PIM segments was higher than in the scarred ones but lower than in the normal regions. The presence of PIM in a specific LV zone was an independent predictor of LAVA. After ablation, PIM value was significantly reduced, mainly due to an increase in perfusion summed rest score, in particular in patients that were responders to ablation. CONCLUSIONS: PIM may associate with VA substrate expressed by LAVA and might provide a novel guide for substrate ablation. A significant reduction of PIM could predict a positive clinical response to ablation.

Prospective use of ablation index for the ablation of right ventricle outflow tract premature ventricular contractions: a proof of concept study.

AIMS: Radiofrequency catheter ablation (RFCA) represents an effective option for idiopathic premature ventricular contractions (PVCs) treatment. Ablation Index (AI) is a novel ablation marker incorporating RF power, contact force, and time of delivery into a single weighted formula. Data regarding AI-guided PVCs RFCA are currently lacking. Aim of the study was to compare AI-guided and standard RFCA outcomes in patients with PVCs originating from the right ventricle outflow tract (RVOT). METHODS AND RESULTS: Consecutive patients undergoing AI-guided RFCA of RVOT idiopathic PVCs were prospectively enrolled. Radiofrequency catheter ablation was performed following per-protocol target cut-offs of AI, depending on targeted area (RVOT free wall AI cut-off: 590; RVOT septum AI cut-off: 610). A multi-centre cohort of propensity-matched (age, sex, ejection fraction, and PVC site) patients undergoing standard PVCs RFCA was used as a comparator. Sixty AI-guided patients (44.2 ± 18.0 years old, 58% male, left ventricular ejection fraction 56.2 ± 3.8%) were enrolled; 34 (57%) were ablated in RVOT septum and 26 (43%) patients in the RVOT free wall area. Propensity match with 60 non-AI-guided patients was performed. Acute outcomes and complications resulted comparable. At 6 months, arrhythmic recurrence was more common in non-AI-guided patients whether in general (28% vs. 7% P = 0.003) or by ablated area (RVOT free wall: 27% vs. 4%, P = 0.06; RVOT septum 29% vs. 9% P = 0.05). Ablation Index guidance was associated with improved survival from arrhythmic recurrence [overall odds ratio 6.61 (1.95-22.35), P = 0.001; RVOT septum 5.99 (1.21-29.65), P = 0.028; RVOT free wall 11.86 (1.12-124.78), P = 0.039]. CONCLUSION: Ablation Index-guidance in idiopathic PVCs ablation was associated with better arrhythmic outcomes at 6 months of follow-up.

Safety and efficacy of transvenous mechanical lead extraction in patients with abandoned leads.

AIMS: Optimal management of redundant or malfunctioning leads is controversial. We aimed to assess safety and efficacy of mechanical transvenous lead extraction (TLE) in patients with abandoned leads. METHODS AND RESULTS: Consecutive TLE procedures performed in our centre from January 2009 to December 2017 were considered. We evaluated the safety and efficacy of mechanical TLE in patients with abandoned (Group 1) compared to non-abandoned (Group 2) leads. We analysed 1210 consecutive patients that required transvenous removal of 2343 leads. Group 1 accounted for 250 patients (21%) with a total of 617 abandoned leads (26%). Group 2 comprised 960 patients (79%) with 1726 leads (74%). The total number of leads (3.0 vs. 2.0), dwelling time of the oldest lead (108.00 months vs. 60.00 months) and infectious indications for TLE were higher in Group 1. Clinical success was achieved in 1168 patients (96.5%) with a lower rate in Group 1 (90.4% vs. 98.1%; P < 0.001). Major complications occurred in only 9 patients (0.7%), without significant differences among the two groups. The presence of one or more abandoned leads [odds ratio (OR) 3.47; 95% confidence interval (CI) 1.07-11.19; P = 0.037] and dwelling time of the oldest lead (OR 1.01 for a month; 95% CI 1.01-1.02; P < 0.001) were associated with a higher risk of clinical failure. CONCLUSION: Transvenous mechanical lead extraction is a safe procedure also in high-risk settings, as patients with abandoned leads. Success rate resulted a bit lower, especially in the presence of abandoned leads with long implantation time.

Interactions between myocardial sympathetic denervation and left ventricular mechanical dyssynchrony: A CZT analysis.

BACKGROUND: A correlation between left ventricular (LV) dyssynchrony (LVD) and impaired myocardial sympathetic tone has been hypothesized. We sought to assess the interactions between regional LV sympathetic innervation, perfusion, and mechanical dyssynchrony. METHODS: Eighty-three patients underwent evaluation of LV perfusion and sympathetic innervation on 99mTc-tetrofosmin/123I-metaiodobenzylguanidine (123I-MIBG) imaging. The summed rest score and summed 123I-MIBG score (SS-MIBG) were computed. The extent of "innervation/perfusion" mismatch was defined as the number of denervated LV segments with relatively preserved perfusion. LVD was evaluated on phase analysis and the wall with latest mechanical activation identified. RESULTS: LVD was revealed in 36 (43%) patients. Patients with LVD had more abnormal values of SRS (21 ± 9 vs 10 ± 8, P < 0.001) and SS-MIBG (29 ± 9 vs 17 ± 11, P < 0.001) than those without LVD. The presence of LVD also clustered with a higher burden of "innervation/perfusion" mismatch (P = 0.019). On per-wall analysis, LV walls with delayed mechanical activation showed a higher burden of "innervation/perfusion" mismatch (2.3 ± 1.4 segments) than normally contracting walls (1.3 ± 1.2 segments; P < 0.001). On multivariate analysis, the extent of "innervation/perfusion" mismatch was the only predictor of delayed mechanical activation (P = 0.029). CONCLUSIONS: Patients with LVD show an elevated burden of "innervation/perfusion" mismatch that is concentrated at the level of the most dyssynchronous walls.

Feasibility and long-term effectiveness of a non-apical Micra pacemaker implantation in a referral centre for lead extraction.

AIMS: To demonstrate the feasibility and long-term performances of a non-apical Micra pacemaker implantation. METHODS AND RESULTS: Fifty-two consecutive patients underwent Micra implantation, targeting a non-apical site of delivery when feasible. Each patient received a regular follow-up (mean 13 ± 9 months). The first 17 patients were also enrolled in the Micra transcatheter pacing system trial (Group 1); the remaining ones presented broader indications and included post-extraction subjects (Group 2). In 19 of 52 patients (Group 1: 6%, Group 2: 51%; P = 0.002) Micra was implanted because of high-risk characteristics that discouraged the implantation of a traditional pacemaker. In 31 of 52 patients (60%) Micra was implanted in a non-apical location, with a lower rate of single delivery compared with apical sites (48% vs. 81%, P = 0.035), but without any impact on electrical performance. Pacing threshold remained optimal in the majority of patients (94%), regardless of the site of implantation (apical vs. non-apical location: 0.50 vs. 0.52 V/0.24 ms; P = 0.856) and group membership, with only 6% of the subjects showing elevated values (mean 1.92 ± 0.92 V/0.24 ms) at the last follow-up. No device-related adverse events were registered. CONCLUSION: Micra pacemaker implant is a safe and effective procedure even in a real life cohort of high-risk patients. A non-apical site of implantation is feasible in the majority of patients allowing stable electrical performance at long-term follow-up.

Micra pacemaker implant after cardiac implantable electronic device extraction: feasibility and long-term outcomes.

AIMS: We aimed at investigating the feasibility and outcome of Micra implant in patients who have previously undergone transvenous lead extraction (TLE), in comparison to naïve patients implanted with the same device. METHODS AND RESULTS: Eighty-three patients (65 males, 78.31%; 77.27 ± 9.96 years) underwent Micra implant at our centre. The entire cohort was divided between 'post-extraction' (Group 1) and naïve patients (Group 2). In 23 of 83 patients (20 males, 86.96%; 73.83 ± 10.29 years), Micra was implanted after TLE. Indication to TLE was an infection in 15 patients (65.21%), leads malfunction in four (17.39%), superior vena cava syndrome in three (13.05%), and severe tricuspid regurgitation in one case (4.35%). The implant procedure was successful in all patients and no device-related events occurred at follow-up (median: 18 months; interquartile range: 1-24). No differences were observed between groups in fluoroscopy time (13.88 ± 10.98 min vs. 13.15 ± 6.64 min, P = 0.45), single device delivery (Group 1 vs. Group 2: 69.56% vs. 55%, P = 0.22), electrical performance at implant and at 12-month follow-up (Group 1 vs. Group 2: pacing threshold 0.48 ± 0.05 V/0.24 ms vs. 0.56 ± 0.25 V/0.24 ms, P = 0.70; impedance 640 ± 148.83 Ohm vs. 583.43 ± 99.7 Ohm, P = 0.27; and R wave amplitude 10.33 ± 2.88 mV vs. 12.62 ± 5.31 mV, P = 0.40). A non-apical site of implant was achievable in the majority of cases (72.3%) without differences among groups (78.26% vs. 70%; P = 0.42). CONCLUSION: Micra implant is an effective and safe procedure in patients still requiring a ventricular pacing after TLE, with similar electrical performance and outcome compared with naïve patients at long-term follow-up.

Contiguity Between Ablation Lesions and Strict Catheter Stability Settings Assessed by VISITAGTM Module Improve Clinical Outcomes of Paroxysmal Atrial Fibrillation Ablation　- Results From the VISITALY Study.

BACKGROUND: Our aim was to evaluate the clinical outcome of paroxysmal atrial fibrillation (AF) ablation with contact force technology, using an automated lesion tagging system (VISITAGTM module) with strict criteria of catheter stability.Methods and Results:We enrolled 200 consecutive patients who underwent pulmonary vein isolation (PVI) in 11 centers and were followed up for 12 months. The stability setting was within 3 mm for ≥10 s and for ≥15 s in 47% and 53% of patients, respectively. A mean of 67.2±21.9 VISITAGs was acquired. Freedom from atrial tachyarrhythmias at follow-up was 77.5% (155/200), and the contiguity between lesions was associated with a higher chronic success rate (96% vs. 77.1%; log-rank P=0.036). Radiofrequency (RF), fluoroscopy times, and recurrence rates at the 12-month follow-up were significantly lower than in a comparison group of 80 patients without VISITAGTM module (42.7±14.5 vs. 50.9±23.6 min; P=0.032; 11.6±7.8 vs. 18.4±12.8 min; P=0.003 and 22.5% vs. 41.2%; P=0.02). Two major complications (1 cardiac tamponade and 1 minor stroke) were observed only in the control group. CONCLUSIONS: Paroxysmal AF ablation with contact force technology and strict criteria of stability using the VISITAG module was a safe procedure, associated with an improvement in efficiency and a reduction of atrial tachyarrhythmia recurrence at the 12-month follow-up compared with manual annotation. Contiguity between lesions seemed to enhance effectiveness outcomes.

The effects of gender on electrical therapies for the heart: procedural considerations, results and complications: A report from the XII Congress of the Italian Association on Arrhythmology and Cardiostimulation (AIAC).

Use of cardiac implantable devices and catheter ablation is steadily increasing in Western countries following the positive results of clinical trials. Despite the advances in scientific knowledge, tools development, and techniques improvement we still have some grey area in the field of electrical therapies for the heart. In particular, several reports highlighted differences both in medical behaviour and procedural outcomes between female and male candidates. Women are referred later for catheter ablation of supraventricular arrhythmias, especially atrial fibrillation, leading to suboptimal results. On the opposite females present greater response to cardiac resynchronization, while the benefit of implantable defibrillator in primary prevention seems to be less pronounced. Differences on aetiology, clinical profile, and development of myocardial scarring are the more plausible causes. This review will discuss all these aspects together with gender-related differences in terms of acute/late complications. We will also provide useful hints on plausible mechanisms and practical procedural aspects.

Relationships between cardiac innervation/perfusion imbalance and ventricular arrhythmias: impact on invasive electrophysiological parameters and ablation procedures.

PURPOSE: To assess the relationship between regional myocardial perfusion and sympathetic innervation parameters at myocardial scintigraphy and intra-cavitary electrophysiological data in patients with ventricular arrhythmias (VA) submitted to invasive electrophysiological study and ablation procedure. METHODS: Sixteen subjects underwent invasive electrophysiological study with electroanatomical mapping (EAM) followed by trans-catheter ablations of VA. Before ablation all patients were studied with a combined evaluation of regional myocardial perfusion and sympathetic innervation by means of tomographic 99mTc-tetrofosmin and 123I- metaiodobenzylguanidine cadmium-zinc-telluride (CZT) scintigraphies, respectively. Off-line spatial co-registration of CZT perfusion and innervation data with the three-dimensional EAM reconstruction was performed in every patient. RESULTS: CZT revealed the presence of myocardial scar in 55 (20 %) segments. Of the viable myocardial segments, 131 (60 %) presented a preserved adrenergic innervation, while 86 (40 %) showed a significantly depressed innervation (i.e. innervation/perfusion mismatch). On EAM, the invasively measured intra-cavitary voltage was significantly lower in scarred segments than in viable ones (1.7 ± 1.5 mV vs. 4.0 ± 2.2 mV, P < 0.001). Interestingly, among the viable segments, those showing an innervation/perfusion mismatch presented a significantly lower intra-cavitary voltage than those with preserved innervation (1.9 ± 2.5 mV vs. 4.7 ± 2.3 mV, P < 0.001). Intra-cardiac ablation was performed in 63 (23 %) segments. On multivariate analysis, after correction for scar burden, the segments showing an innervation/perfusion mismatch remained the most frequent ablation targets (OR 5.6, 95 % CI 1.5-20.8; P = 0.009). CONCLUSIONS: In patients with VA, intra-cavitary electrical abnormalities frequently originate at the level of viable myocardial segments with depressed sympathetic innervation that frequently represents the ultimate ablation target.

Near zerO fluoroscopic exPosure during catheter ablAtion of supRavenTricular arrhYthmias: the NO-PARTY multicentre randomized trial.

AIMS: Aim of this study was to compare a minimally fluoroscopic radiofrequency catheter ablation with conventional fluoroscopy-guided ablation for supraventricular tachycardias (SVTs) in terms of ionizing radiation exposure for patient and operator and to estimate patients' lifetime attributable risks associated with such exposure. METHODS AND RESULTS: We performed a prospective, multicentre, randomized controlled trial in six electrophysiology (EP) laboratories in Italy. A total of 262 patients undergoing EP studies for SVT were randomized to perform a minimally fluoroscopic approach (MFA) procedure with the EnSiteTMNavXTM navigation system or a conventional approach (ConvA) procedure. The MFA was associated with a significant reduction in patients' radiation dose (0 mSv, iqr 0-0.08 vs. 8.87 mSv, iqr 3.67-22.01; P < 0.00001), total fluoroscopy time (0 s, iqr 0-12 vs. 859 s, iqr 545-1346; P < 0.00001), and operator radiation dose (1.55 vs. 25.33 µS per procedure; P < 0.001). In the MFA group, X-ray was not used at all in 72% (96/134) of cases. The acute success and complication rates were not different between the two groups (P = ns). The reduction in patients' exposure shows a 96% reduction in the estimated risks of cancer incidence and mortality and an important reduction in estimated years of life lost and years of life affected. Based on economic considerations, the benefits of MFA for patients and professionals are likely to justify its additional costs. CONCLUSION: This is the first multicentre randomized trial showing that a MFA in the ablation of SVTs dramatically reduces patients' exposure, risks of cancer incidence and mortality, and years of life affected and lost, keeping safety and efficacy. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01132274.

Subcutaneous implantable cardiac defibrillators: indications and limitations.

The implantable cardioverter defibrillator is today an indisputable evidence-based treatment for cardiac sudden death both in primary and secondary prevention. However, trans-venous cardioverter defibrillator implantation still carries a not negligible risk of complications both acutely and during follow-up. Trans-venous endocardial lead is the weak link of implantable cardioverter defibrillator (ICD) technology being the source of most mechanical complications on vessels and heart structures and exposed to infection, malfunction and recalls. A totally subcutaneous defibrillation lead has recently been introduced in clinical practice. With the subcutaneous pulse generator forms a defibrillation system that leaves the vessels and the heart completely "untouched." Subcutaneous ICD has proven to be safe and effective in many clinical trials. Patients without pacing indications and at higher risk of complications from trans-venous lead implantation represent the perfect candidates to S-ICD technology. However, with technical improvement, it is reasonable to expect a further expansion of indications.

Safety and efficacy of internal transjugular approach for transvenous extraction of implantable cardioverter defibrillator leads.

AIMS: We report our 15 years experience of a mechanical single-sheath technique with a multiple venous entry-site approach. We evaluated the effectiveness and safety of this technique in implantable defibrillator (ICD) lead extraction and investigated the potential association between clinical and lead-related factors and procedural complexity. METHODS AND RESULTS: The proposed technique consists of an initial attempt at manual traction, followed by mechanical dilatation performed through the venous entry-site and, if necessary, by crossover to the internal transjugular approach. The study cohort comprised 545 consecutive patients referred to our institution for transvenous lead extraction from January 1997 to December 2012. Initial manual traction resulted in the effective removal of 6% of leads. Mechanical dilatation increased the success rate to 89% when performed through the venous entry-site, and to 99% when subsequently attempted via the internal jugular vein. No major complications were associated with lead extraction. Dwell-time, a passive fixation mechanism and dual-coil lead design were independently associated with the need for mechanical dilatation. However, dwell-time was the only variable associated with crossover to the internal transjugular approach. Specifically, a dwell-time of 20 months best predicted the need for venous entry-site mechanical dilatation, while a value of 55 months predicted crossover to the internal transjugular approach. CONCLUSION: Mechanical transvenous extraction of ICD leads is a complex but safe and effective procedure. A longer lead dwell-time is associated with the need for mechanical dilatation and for crossover to the internal transjugular approach; this should be considered when planning the removal procedure. Moreover, passive lead fixation and dual-coil lead design predict a more challenging extraction procedure.

Updated national multicenter registry on procedural safety of catheter ablation for atrial fibrillation.

INTRODUCTION: Despite catheter ablation (CA) becoming an accepted treatment option for symptomatic, drug-resistant atrial fibrillation (AF), safety of this procedure continues to be cause for concern. Aim of the present multicenter registry was to assess the incidence of early CA complications and detect their predictors in a contemporary, unselected AF population METHODS AND RESULTS: From January 1, 2011 to December 31, 2011, data from 2,323 consecutive patients who underwent CA (median age 60 [52-67]; 72.3% male) for AF in 29 Italian centers were collected. All major complications occurring to the patient from admission to 30th postprocedural day were recorded. No procedure-related death was observed. Major complications occurred in 94 patients (4.0%): 50 patients (2.2%) suffered vascular access complications; 12 patients (0.5%) developed cardiac tamponade; 14 patients (0.6%) presented with pericarditis; 5 patients (0.2%) had transient ischemic attack; 4 patients had stroke; 3 patients (0.1%) had phrenic nerve paralysis; 3 patients (0.1%) had hemothorax. Other isolated but serious adverse events were documented in 3 patients (0.1%). Female gender (OR 2.643; 95% CI 1.686-4.143; P < 0.0001) and longer procedural duration (OR 2.195; 95% CI 1.388-3.473; P < 0.001) independently predicted a higher risk of complications. CONCLUSION: Major complications occurred in 4.0% of the CA procedures for AF, with vascular access complications being the most frequent events.

Port-a-Cath complicated by infection or migration not removed by manual traction: usefulness of cardiac pacing leads extraction techniques.

BACKGROUND: Long-term use of Port-a-Caths (PACs) is related to device-related delayed complications. The aim of this study is to describe the high success rate and safety of cardiac pacing lead extraction techniques used for PACs complicated by infection or migration and not removed by manual traction. METHODS: During a 13-year period (1997-2010), 19 consecutive PAC recipients (54.1±13 years, 11 females) were referred to our hospital for PAC-related delayed complications and PACs not removable by manual traction (mean dwelling time 29.3±31 months). RESULTS: PAC implantation indications included gastrointestinal cancer (21%), breast cancer (15.7%), other malignant diseases (52.6%), and nonmalignant diseases (10.5%). PAC removal indications were breakdown due to subclavian crush (63.1%), breakdown due to unsuccessful previous removal attempt (21%), sepsis (10.5%), or malfunction (5.3%). Removal of fractured free-floating catheters (16) migrated toward the venous blood course was attempted by tool-guided traction in all cases except 1 in whom mechanical dilation was necessary. For the 3 intact ones (2 infected and one malfunctioning) we used tool-guided traction and single-sheath mechanical dilation, depending on the vascular/cardiac-catheter setting. By using multiple venous approaches we removed 18 catheters completely and 1 partially, achieving clinical success in all of the patients. The most commonly used venous approach was transfemoral (TFA; 73.6%), followed by the original venous entry site approach (VEA; 15.7%) and internal transjugular approach (ITA; 10.5%). No major or minor complications were observed. CONCLUSIONS: In experienced centers, cardiac pacing lead extraction techniques may be considered as an additional, efficacious, safe option for extraction of otherwise nonremovable entrapped PACs before surgery.

Micafungin for Candida albicans pacemaker-associated endocarditis: a case report and review of the literature.

We report on the treatment with micafungin of a pacemaker-associated endocarditis due to Candida albicans. Antifungal therapy was able to reduce vegetation size from 5 to 1 cm making possible the transvenous removal of the device without a high risk of pulmonary embolism. Noteworthy, a high micafungin concentration was documented into the lead vegetation (10 µg/g of vegetation tissue) and this may have contributed to the striking size reduction of vegetation.

Feasibility and Accuracy of Noninvasive Continuous Arterial Pressure Monitoring during Transcatheter Atrial Fibrillation Ablation.

INTRODUCTION: Transcatheter atrial fibrillation (AF) ablation is still carried out with continuous invasive radial arterial blood pressure (IBP) monitoring in many centers. Continuous noninvasive blood pressure (CNBP) measurement using the volume-clamp method is a noninvasive alternative method used in ICU. No data on CNBP reliability are available in the electrophysiology lab during AF ablation, where rhythm variations are common. BACKGROUND: The objective of the present study was to compare continuous noninvasive arterial pressure measured with the ClearSight device (Edwards Lifesciences, Irvine, CA, USA) with invasive radial artery pressure used as the reference method during AF ablation. METHODS: We prospectively enrolled 55 consecutive patients (age 62 ± 11 years, 80% male) undergoing transcatheter AF ablation (62% paroxysmal, 38% persistent) at our center. Standard of care IBP monitoring via a radial cannula and a contralateral noninvasive finger volume-clamp CNBP measurement device were positioned simultaneously in all patients for the entire procedure. Bland-Altman analysis was used to analyze the agreement between the two techniques. RESULTS: A total of 1219 paired measurements for systolic, diastolic, and mean arterial pressure were obtained in 55 subjects, with a mean (SD) of 22 (9) measurements per patient. The mean bias (SD) was -12.97 (13.89) mmHg for systolic pressure (level of agreement -14.24-40.20; correlation coefficient 0.84), -1.85 (8.52) mmHg for diastolic pressure (level of agreement -18.54-14.84; correlation coefficient 0.77) and 2.31 (8.75) mmHg for mean pressure (level of agreement -14.84-19.46; correlation coefficient 0.85). CONCLUSION: In patients undergoing AF ablation, CNBP monitoring with the ClearSight device showed acceptable agreement with IBP monitoring. Larger studies are needed to confirm the potential clinical implications of continuous noninvasive BP monitoring during AF ablation.

Microbiology of cardiac implantable electronic device infections.

AIMS: The aim of the study was to describe the microbiological findings of cardiac implantable electronic devices (CIEDs) infection in the 2000-2011 period at the Cardiology Unit of New Santa Chiara Hospital in Pisa (Italy). METHODS AND RESULTS: Removed CIED leads and pocket material were seeded on solid media and isolates tested for antimicrobial susceptibility with the Kirby Bauer method. Electrodes from 1204 patients were analysed and 854 (70.9%) tested positive. In 663 (77.6%) cases only one species was isolated, in 175 (20.5%) two species, and in 14 (1.8%) >2 species. In 116 cases material from the pocket was also cultured. The result was consistent with that from the electrodes in 69 (59%) cases. In 359 cases a blood sample was also obtained for culture. The result was consistent with that from the leads in 124 (35%) cases. A total of 1068 strains were isolated from electrodes. Gram-positive organisms were most frequently isolated (92.5% of isolates); particularly, coagulase-negative staphylococci (CoNS), mainly Staphylococcus epidermidis, in 69% of cases and Staphylococcus aureus in 13.8%, Gram-negative rods in 6.1%, yeasts in 1% and molds in 0.4%. Overall, Oxacillin resistance was 30%, in particular 33% among CoNS and 13% among S. aureus. Oxacillin resistance and quinolones resistance have increased in the period 2006-2011 with respect to the 5 years before. Seventeen percent of Enterobacteriaceae strains had a phenotype compatible with extended spectrum beta-lactamase expression. CONCLUSIONS: Culture of the leads offers the possibility of an aetiological diagnosis in the majority of cases. When material from the pocket can be obtained, the microbiological result is often consistent with that from the electrodes, while species isolated from blood cultures are often different and more likely to be the result of contamination. Cardiac implantable electronic device infection is more often monomicrobial, CoNS are most frequently isolated and S. epidermidis is largely the main single agent. Very early infections were associated with S. aureus infection. The pattern of susceptibility to antimicrobials is in general that of community-acquired infections, although oxacillin resistance and quinolones resistance has increased in the last 5 years.

Reduced fluoroscopy exposure during ablation of atrial fibrillation using a novel electroanatomical navigation system: a multicentre experience.

AIMS: Catheter ablation of atrial fibrillation (AF) focuses on pulmonary vein (PV) ablation with or without additional atrial substrate modification. These procedures require significant fluoroscopy exposure. A new 3D non-fluoroscopic navigation system (CARTO(®) 3 System, Biosense Webster, CA, USA) that allows precise location visualization of diagnostic and ablation catheters was evaluated for its impact on fluoroscopic exposure during AF ablation procedures. METHODS AND RESULTS: Two groups of patients were treated by our centres for drug refractory AF. One group was treated using the new CARTO(®) 3 system to guide catheter ablation (Group A, 117 patients). The other group was treated using the CARTO(®) XP system (Biosense Webster) 3 months previously (Group B, 123 patients). For both groups, circumferential PV ostia ablation was performed; PV isolation was validated using a circular catheter placed at each ostium. There was no difference in any clinical characteristics (age, sex, AF type, left atrium diameter and volume, and heart disease) among the two study groups. The mean number of PVs identified and isolated per patient was similar in both groups, as were the mean procedural duration and radiofrequency time. However, mean fluoroscopic time was significantly reduced in Group A (15.9±12.3 min) as compared with Group B (26±15.1 min) (P < 0.001). CONCLUSION: This multicentre observational study demonstrates a significant reduction of fluoroscopy exposure using a new 3D non-fluoroscopic mapping system to guide AF catheter ablation.

Cardiac resynchronization therapy after coronary sinus lead extraction: feasibility and mid-term outcome of transvenous reimplantation in a tertiary referral centre.

AIMS: Few data are available on cardiac resynchronization therapy (CRT) after coronary sinus (CS) lead extraction. We aimed to evaluate the feasibility and mid-term outcome of transvenous CS lead reimplantation in a tertiary referral centre. METHODS AND RESULTS: We enrolled all patients who were referred to our hospital for CS lead removal from December 2000 through to May 2009 and were transvenously reimplanted with a CRT system before June 2009. One-year follow-up was performed to evaluate the incidence of infections, malfunctions, and mortality. We studied 113 consecutive patients undergoing successful CS lead extraction; 90 patients (75 male, mean age 69.2, range 35-84) underwent CS lead reimplantation (success rate: 95.6%; right-sided approach: 64.4%). In these patients, cardiac device infection was the usual indication for extraction (74.4%) and the subsequent reimplantation was performed after a median time of 3 days. The coronary sinus lead was usually positioned in the left ventricular (LV) postero-lateral region (62.2%); two procedures were required in two cases (2.2%). Balloon angioplasty was necessary for two patients (failure in one), whereas for the others we used a conventional implant technique. During follow-up, we observed four cases (4.4%) of local infection and six cases (6.7%) of system malfunction, requiring reintervention (two cases during the same hospitalization). One-year mortality was 5.5%. CONCLUSION: Left ventricular lead reimplantation is in our experience an effective and safe procedure, also in the case of right-sided approach. During follow-up, 1-year mortality was particularly low, whereas overall infection rate was higher than first implant procedures.

Large, single-center experience in transvenous coronary sinus lead extraction: procedural outcomes and predictors for mechanical dilatation.

BACKGROUND: The aim of this study was to evaluate procedural outcomes of coronary sinus (CS) lead extraction, focusing on predictors and need for mechanical dilatation (MD) in the event that manual traction (MT) is ineffective. METHODS: The study assessed results in 145 consecutive patients (age 69 ± 10 years; 121 men)--a total of 147 CS pacing leads--who underwent transvenous CS lead removal between January 2000 and March 2010. RESULTS: All leads but one (99%) (implantation time 29 ± 25 months) were successfully removed. MT was effective in 103 (70%), and MD was necessary in the remaining 44 (30%) procedures. In multivariate analyses, unipolar design (odds ratio [OR] 3.22, 95% confidence interval [CI] 1.43-7.7; P = 0.005) and noninfective indication (OR 4.8, 95% CI 1.8-13, P = 0.002) were independent predictors for MD (P < 0.0001), with a predictive trend for prior cardiac surgery (OR 2.2, 95% CI 0.98-5.26; P = 0.06). Five (3.4%) complex procedures required a transfemoral vein approach (TFA) or repeat procedure. No deaths occurred, and there was one major complication (0.7%), cardiac tamponade, after MT. No complication predictors were identified. CONCLUSIONS: CS leads were safely and effectively removed in nearly all patients, and 70% were removed with MT alone; 30% required MD. Preoperative predictors suggesting the need for MD or TFA were noninfective indication and unipolar lead design. Complications were rare, and there was no predictable pattern among MT or MD removal techniques.