Efficiency of the RADPAD Surgical Cap in Reducing Brain Exposure During Pacemaker and Defibrillator Implantation.

OBJECTIVES: This study sought to investigate the RADPAD No Brainer (Worldwide Innovation and Technologies, Overland Park, Kansas) efficiency in reducing brain exposure to scattered radiation. BACKGROUND: Cranial radioprotective caps such as the RADPAD No Brainer are being marketed as devices that significantly reduce operator's brain exposure to scattered radiation. However, the efficiency of the RADPAD No Brainer in reducing brain exposure in clinical practice remains unknown to date. METHODS: Five electrophysiologists performing device implantations over a 2-month period wore the RADPAD cap with 2 strips of 11 thermoluminescent dosimeter pellets covering the front head above and under the shielded cap. Phantom measurements and Monte Carlo simulations were performed to further investigate brain dose distribution. RESULTS: Our study showed that the right half of the operators' front head was the most exposed region during left subpectoral device implantation; the RADPAD cap attenuated the skin front-head exposure but provided no protection to the brain. The exposure of the anterior part of the brain was decreased by a factor of 4.5 compared with the front-head skin value thanks to the skull. The RADPAD cap worn as a protruding horizontal plane, however, reduced brain exposure by a factor of 1.7 (interquartile range: 1.3 to 1.9). CONCLUSIONS: During device implantation, the RADPAD No Brainer decreased the skin front head exposure but had no impact on brain dose distribution. The RADPAD No Brainer worn as a horizontal plane worn around the neck reduces brain exposure and confirms that the exposure comes from upward scattered radiation.

Impact of contact force sensing technology on outcome of catheter ablation of idiopathic pre-mature ventricular contractions originating from the outflow tracts.

AIMS: Catheter ablation of frequent idiopathic pre-mature ventricular contractions (PVC) is increasingly performed. While potential benefits of contact force (CF)-sensing technology for atrial fibrillation ablation have been assessed in several studies, the impact of CF-sensing on ventricular arrhythmia ablation remains unknown. This study aimed to compare outcomes of idiopathic outflow tract PVC ablation when using standard ablation catheters as opposed to CF-sensing catheters. METHODS AND RESULTS: In a retrospective multi-centre study, unselected patients undergoing catheter ablation of idiopathic outflow tract PVCs between 2013 and 2016 were enrolled. All procedures were performed using irrigated-tip ablation catheters and a 3D electro-anatomical mapping system. Sustained ablation success was defined as a ≥80% reduction of pre-procedural PVC burden determined by 24 h Holter ECG during follow-up. Overall, 218 patients were enrolled (median age 52 years, 51% males). Baseline and procedural data were similar in the standard ablation (24%) and the CF-sensing group (76%). Overall, the median PVC burden decreased from 21% (IQR 10-30%) before ablation to 0.2% (IQR 0-3.0%) after a median follow-up of 2.3 months (IQR 1.4-3.9 months). The rates of both acute (91% vs. 91%, P = 0.94) and sustained success (79% vs. 74%, P = 0.44) were similar in the standard ablation and the CF-sensing groups. No differences were observed in subgroups according to arrhythmia origin from the RVOT (65%) or LVOT (35%). Complications were rare (1.8%) and evenly distributed between the two groups. CONCLUSION: The use of CF-sensing technology is not associated with increased success rate nor decreased complication rate in idiopathic outflow tract PVC ablation.

[The year in cardiology : 2018]. / Cardiologie.

This review article provides a broad overview of the novelties in cardiology in 2018. Advances in interventional cardiology and cardiovascular prevention, heart failure, electrophysiology and non-invasive cardiovascular imaging have provided important new insights in the pathophysiology, diagnosis and treatment of ischemic and valvular heart disease, heart failure, rhythm disorders and cardiomyopathies. This article provides an overview of the most relevant articles published in 2018.

L'année 2018 a été riche en nouveautés dans les domaines de la cardiologie interventionnelle, de l'insuffisance cardiaque, de l'électrophysiologie et de l'imagerie cardiaque. Les progrès dans ces domaines respectifs ont fourni de nouveaux outils pour le diagnostic et le traitement des cardiopathies ischémiques et valvulaires, de l'insuffisance cardiaque à fraction d'éjection réduite ou préservée, des troubles du rythme et des cardiomyopathies. Cet article fournit un aperçu des articles les plus pertinents publiés en 2018.

Leadless pacing using the transcatheter pacing system (Micra TPS) in the real world: initial Swiss experience from the Romandie region.

AIMS: Leadless pacemakers are implanted in Switzerland since June 2015. Large worldwide registries have shown high implant success, low complication rates, and good electrical parameters up to 12 months' follow-up. However, data are scarce outside the investigational setting. The purpose of this study is to assess the real-world experience regarding clinical safety and efficacy of Micra TPS (transcatheter pacing system) leadless pacemakers. METHODS AND RESULTS: Retrospective observational, multi-centre study designed to assess initial safety and efficacy of the Micra TPS in the Swiss Romande region. A total of 92 patients were included from four different centres with an implantation success rate of 97.8% (90 of 92). Thresholds were overall low at implantation (median 0.38 V/0.24 ms, ranging from 0.13 to 2.88 V/0.24 ms) and remained stable over 1-year follow-up. The perioperative serious adverse event rate was 6.5% in six patients which lead to prolonged hospitalization in five patients and death in one patient. In addition, three further major events (3.3%) occurred during an average follow-up of 1 year, requiring implantation of a standard transvenous pacemaker in two patients, and surgical explantation of the Micra TPS in one patient due to intractable ventricular tachycardia. CONCLUSION: Leadless pacemakers are a valuable adjunct for treating selected patients requiring single-chamber pacing. However, in this initial experience, major complication rates were high (9.8%). The implant procedure requires proper training and should be performed in an adequate setting.

[Cardiac sarcoidosis: seven keypoints to remind in order to avoid misdiagnosis]. / Sarcoïdose cardiaque: sept points à rappeler pour ne pas manquer le diagnostic.

Early diagnosis of cardiac sarcoidosis remains difficult in the absence of specific symptoms. The evolution and prognosis of the disease are strongly correlated to an early and appropriate treatment. The multi-modality assessment based on cardiac MRI and positron emission tomography associated with computed tomography (PET/CT) has significantly improved the detection of cardiac sarcoidosis over the last two decades. These approaches appear as useful and suitable imaging strategy for the early diagnosis, the assessment of the disease extent as well as the management and therapeutic follow-up. This article is a didactic review on cardiac sarcoidosis, with a special focus on recent diagnostic and therapeutic modalities, prognosis and interest of imaging techniques.

Nonlinear analysis of right atrial electrograms predicts termination of persistent atrial fibrillation within the left atrium by catheter ablation.

The termination of long-standing persistent atrial fibrillation (LS-pAF) can be achieved by stepwise catheter ablation (step-CA) within the left atrium (LA). Our study aims to applying complexity measures derived from nonlinear time series analysis in order to characterize LS-pAF in terms of organization and to identify patients in whom AF can be terminated from those in whom AF cannot be terminated by step-CA within the LA. A total of 33 consecutive patients (age 61 ± 7 years, sustained AF duration 19 ± 11 months) with LS-pAF underwent step-CA. The organization of right bipolar electrograms before and during the ablation procedure was assessed using the coarse-grained correlation dimension. LS-pAF was terminated into sinus rhythm or atrial tachycardia in 22 patients during step-CA within the LA (left terminated patients-LT). In 11 patients the ablation procedure failed to terminate AF within LA (not left terminated patients-NLT). The statistical analysis of the estimated coarse-grained correlation dimension revealed that a higher right atrial (RA) organization before step-CA was associated to AF termination within the LA. During the ablation procedure, the level of RA organization displayed distinctive evolution between LT and NLT patients with a significant organization increase before AF termination for the LT patients.

A High Baseline Electrographic Organization Level Is Predictive of Successful Termination of Persistent Atrial Fibrillation by Catheter Ablation.

OBJECTIVES: This study sought to investigate whether the level of organization of electrocardiographic (ECG) signals based on novel indexes is predictive of persistent atrial fibrillation (pAF) termination by catheter ablation (CA). BACKGROUND: Whether the level of ECG organization in pAF is correlated with the restoration of sinus rhythm by CA remains unknown. METHODS: Thirty consecutive patients who underwent stepwise CA for pAF (sustained duration 19 ± 11 months) were included in the study (derivation cohort). ECG lead V6 was placed on the patients' back (V6b) to improve left atrial (LA) recording. Two novel ECG indexes were computed using an adaptive harmonic frequency tracking scheme: 1) the adaptive organization index (AOI), which quantifies the cyclicity of AF harmonic oscillations; and 2) the adaptive phase index (API), which quantifies the phase coupling between the harmonic components. Index cutoff values predictive of procedural AF termination were then tested on a validation cohort of 8 consecutive patients. RESULTS: In the derivation cohort, CA terminated AF in 21 patients within the LA (70%; left-terminated [LT] group), whereas CA did not terminate AF in 9 patients (30%; non-left-terminated [NLT] group). LT patients displayed a higher ECG organization level at baseline than the NLT patients, with the best separation achieved by AOI and API computed on lead V1 (area under the curve [AUC] = 0.94 and AUC = 0.88, respectively; p < 0.05) and API on lead V6b (AUC = 0.83; p < 0.05). Similar results were obtained for both AOI and API in the validation cohort. CONCLUSIONS: Patients in whom pAF terminated within the LA exhibited a higher level of atrial ECG organization, which was suggestive of a limited number of LA drivers than that of patients in whom the pAF could not be terminated by CA.

Short-Term Heparin Kinetics during Catheter Ablation of Atrial Fibrillation.

BACKGROUND: Percutaneous catheter ablation of atrial fibrillation (CA-AF) is a treatment option for symptomatic drug-refractory atrial fibrillation (AF). CA-AF carries a risk for thromboembolic complications that has been minimized by the use of intraprocedural intravenous unfractionated heparin (UFH). The optimal administration of UFH as well as its kinetics are not well established and need to be precisely determined. METHODS AND RESULTS: A total 102 of consecutive patients suffering from symptomatic drug-refractory AF underwent CA-AF. The mean age was 61 ± 10 years old. After transseptal puncture of the fossa ovalis, weight-adjusted UFH bolus (100 U/kg) was infused. A significant increase in activated clotting time (ACT) was observed from an average value of 100 ± 27 seconds at baseline, to 355 ± 94 seconds at 10 min (T10), to 375 ± 90 seconds at 20 min (T20). Twenty-four patients failed to reach the targeted ACT value of ≥300 seconds at T10 and more than half of these remained with subtherapeutic ACT values at T20. This subset of patients showed similar clinical characteristics and amount of UFH but were more frequently prescribed preprocedural vitamin K1 than the rest of the study population. CONCLUSIONS: In a typical intervention setting, UFH displays unexpected slow anticoagulation kinetics in a significant proportion of procedures up to 20 minutes after infusion. These findings support the infusion of UFH before transseptal puncture or any left-sided catheterization with early ACT measurements to identify patients with delayed kinetics. They are in line with recent guidelines to perform CA-AF under therapeutic anticoagulation.

Remote-controlled magnetic pulmonary vein isolation combined with superior vena cava isolation for paroxysmal atrial fibrillation: a prospective randomized study.

BACKGROUND: Radiofrequency ablation (RFA) of paroxysmal atrial fibrillation (PAF) has focused on pulmonary vein isolation (PVI). However, despite initial positive results, significant recurrences have occurred, partly because of pulmonary vein (PV) reconnection or non-PV ectopic foci, including the superior vena cava (SVC). OBJECTIVES: This prospective, randomized study sought to investigate the efficacy of additional SVCI combined with PVI in symptomatic PAF patients referred for ablation. METHODS: From November 2011 to May 2013, RFA was performed remotely using a CARTO(®) 3 System in patients randomized to undergo PVI for symptomatic drug-refractory PAF, with (PVI+SVCI group) or without (PVI alone group) SVCI. PVI and SVCI were confirmed by spiral catheter recording during ablation. Procedural data, complications and freedom from atrial tachycardia (AT) and atrial fibrillation (AF) were assessed. RESULTS: Over an 18-month period, 100 consecutive patients (56±9years; 17 women) with symptomatic PAF were included in the study (PVI+SVCI, n=51; PVI, n=49); the CHA2DS2-VASc score was 0.9±1. Median duration of procedure (±interquartile), 2.5±1hours; total X-ray exposure, 13.3±8minutes; transseptal puncture and catheter positioning, 8±5minutes; left atrium electroanatomical reconstruction, 3±2minutes; and catheter ablation, 3.7±3minutes. After a median follow-up of 15±8months, and having undergone a single procedure, 84% of patients were symptom free, while 86% remained asymptomatic after undergoing two procedures. The cumulative risks of atrial arrhythmias (AT or AF) were interpreted using Kaplan-Meier curves and compared using the log-rank test. Long-term follow-up revealed no significant difference between groups, with atrial arrhythmias occurring in six (12%) patients in the PVI+SVCI group and nine (18%) patients in the PVI alone group (P=0.6). One transient phrenic nerve palsy and one phrenic nerve injury with partial recovery occurred in the PVI+SVCI group. CONCLUSIONS: SVCI combined with PVI did not reduce the risk of subsequent AF recurrence, and was responsible for two phrenic nerve injuries. Accordingly, the benefit-to-risk ratio argues against systematic SVCI.

Does a patent foramen ovale matter when using a remote-controlled magnetic system for pulmonary vein isolation?

BACKGROUND: Pulmonary vein isolation (PVI) takes longer when using a patent foramen ovale (PFO) compared with a transseptal puncture in paroxysmal atrial fibrillation (AF) with manual catheter ablation. To our knowledge, no data exist concerning the impact of a PFO on AF ablation procedure variables when using a remote magnetic navigation (RMN) system. AIM: To assess the impact of a PFO when using an RMN system in patients requiring AF ablation. METHODS: Between December 2011 and December 2012, catheter ablation was performed remotely using the CARTO(®) 3 system in 167 consecutive patients who underwent PVI for symptomatic drug-refractory AF. The radiofrequency generator was set to a fixed power ≤ 35 W. The primary endpoint was wide-area circumferential PVI confirmed by spiral catheter recording during ablation for all patients and including additional lesion lines (left atrial roof) or complex fractionated atrial electrograms for persistent AF. Secondary endpoints included procedural data. RESULTS: Mean age 58±10 years; 18% women; 107 (64%) patients with symptomatic paroxysmal AF; 60 (36%) with persistent AF; CHA2DS2-VASc score 1.2 ± 1. The PFO presence was evidenced in 49/167 (29.3%) patients during the procedure but in only 26/167 (16%) by transoesophageal echocardiography. Median procedure time 2.5 ± 1 hours; median total X-ray exposure time 14 ± 7 minutes; transseptal puncture and catheter positioning time 7.5 ± 5 minutes; left atrium electroanatomical reconstruction time 3 ± 2.3 minutes; catheter ablation time 3 ± 3 minutes. No procedure time or X-ray exposure differences were observed between patients with or without a PFO during magnetic navigation catheter ablation. X-ray exposure time was significantly reduced using a PFO compared with double transseptal puncture access. CONCLUSIONS: A PFO does not affect magnetic navigation during AF ablation; procedure times and X-ray exposure were similar. Septal catheter probing is mandatory to limit X-ray exposure and prevent potential complications.

Remote-controlled magnetic pulmonary vein isolation using a new three-dimensional non-fluoroscopic navigation system: a single-centre prospective study.

BACKGROUND: Catheter ablation of atrial fibrillation (AF) focuses on pulmonary vein isolation (PVI), but the procedure is associated with significant X-ray exposure. Few data exist concerning the combination of remote magnetic navigation (RMN) and a new three-dimensional non-fluoroscopic navigation system (Carto(®) 3), which facilitates precise catheter navigation and limits X-ray exposure. AIMS: To assess the efficacy and extent of fluoroscopic exposure associated with the combination of RMN and the Carto 3 system in patients requiring AF ablation. METHODS: Between January and September 2011, catheter ablation was performed remotely using the Carto 3 system in 81 consecutive patients who underwent PVI for symptomatic drug-refractory AF. The radiofrequency generator was set to a fixed power ≤ 35W. The primary endpoint was wide-area circumferential PVI confirmed by spiral catheter recording during ablation and including additional lesion lines (left atrial roof and coronary sinus defragmentation) or complex fractionated atrial electrograms for persistent AF. Secondary endpoints included procedural data, complications and freedom from atrial tachycardia (AT)/AF. RESULTS: Mean age was 60 ± 9 years; 20% were women; 73% had symptomatic paroxysmal AF; 27% had persistent AF. The CHA2DS2-VASc score was 1.2 ± 1. Median procedure time was 3.5 ± 1 hours; median total X-ray exposure time was 13 ± 7 minutes; transseptal puncture and catheter positioning took 8 ± 4 minutes, left atrium electroanatomical reconstruction 1 ± 4 minutes and catheter ablation 3.5 ± 5minutes. Recurrences were AT (n=3; 3.7%), paroxysmal AF (n=8; 9.9%) and persistent AF (n=4; 4.9%); redo ablation was performed in these 15 (19%) patients. After a median follow-up of 15 ± 6 months and a single procedure, 71% of patients were free of symptoms; 84% remained asymptomatic after two procedures. CONCLUSIONS: RMN with irrigated catheters combined with the Carto 3 system can be effectively performed in patients requiring AF ablation with minimal use of fluoroscopy, but larger randomized studies are warranted.

Remote magnetic navigation and arrhythmia ablation.

Radiofrequency treatment is the first-choice treatment for arrhythmias, in particular complex arrhythmias and especially atrial fibrillation, due to the greater benefit/risk ratio compared with antiarrhythmic drugs. However, complex arrhythmias such as atrial fibrillation require long procedures with additional risks such as X-ray exposure or serious complications including tamponade. Given this context, robotic magnetic navigation is a technique well suited to the treatment of complex arrhythmias, on account of its efficacy and reliability, the significant reduction in X-ray exposure for both patient and operator, and the very low risk of perforation. As ongoing developments will likely improve results and procedure times, this technology will become one of the most advanced for treating arrhythmias.

A single-centre experience concerning the safety of Sprint Fidelis defibrillator lead extraction at the time of pulse generator replacement or in case of evidence of lead failure.

BACKGROUND: The reported failure rate of the Sprint Fidelis defibrillator lead (SFDL) has increased more than initially expected, with emerging evidence of accelerating fracture rates. Current consensus guidelines continue to discourage prophylactic lead extraction, citing major complication rates of 1.4-7.3%. Therefore, data relating to the risks of systematic SFDL extraction are lacking, with no methodical extraction protocol reported to date. Moreover, few statistical analyses have identified predictors of SFDL failure. OBJECTIVES: The aims of this single-centre study were: to examine the safety and feasibility of systematic SFDL extraction at the time of pulse generator replacement or in case of lead failure; and to identify predictors of SFDL failure. METHODS: Between January 2005 and October 2007, 218 consecutive patients underwent transvenous SFDL implantation in our centre. RESULTS: During a mean follow-up of 43 ± 15 months, SFDL extraction was performed in 49 patients (22.5%) for the following reasons: inappropriate shocks (n = 21; 9.6%), systematic extraction at time of pulse generator extraction (n = 23; 10.5%), high impedance (n = 3; 1.4%), high SFDL threshold (n = 1; 0.4%) and cardiac device-related infection (n = 1; 0.4%). No severe complications occurred, although two minor complications were reported (lead dislodgments). SFDL fracture was observed in 25 patients (11.5%; 3.2%/year incidence). The only predictor associated with SFDL fracture was the number of leads (P = 0.01). CONCLUSION: In our series, SFDL extraction at the time of pulse generator extraction or in case of evidence of lead failure was feasible and safe. Number of leads was identified as a new predictive factor for SFDL fracture.

Single-centre experience with an 8-mm tip catheter for radiofrequency catheter ablation of outflow tract ventricular ectopic beats.

BACKGROUND: Radiofrequency ablation (RFA) of outflow tract ventricular ectopic beats (OTVEBs) can be performed using a 4-mm or externally-cooled tip RFA catheter, but no data are available concerning the safety and efficacy of a large-tip (8-mm) catheter. AIMS: To evaluate the feasibility of using an 8-mm tip catheter in patients with OTVEBs. METHODS: In this prospective cohort study, the 8-mm tip catheter was tested in patients who were referred to our centre for RFA of symptomatic OTVEBs. RESULTS: The mean age of the 16 patients recruited between September 2008 and March 2010 was 53±18 years and 56.3% were male. Mean left ventricular ejection fraction was 62±9%, mean ventricular ectopic beat width was 144±21 ms, and all patients had left bundle branch block. Fourteen patients had inferior axis QRS morphology and two had superior. The main symptoms were palpitations and pre-syncope. RFA parameters were: procedure time 94±35 min; duration of application 11±10 min; impedance 81±12 Ω; temperature 50±5 °C; and power 46±17 W. RFA succeeded in 15 over 16 patients (93.8%); and recurrence was seen in one patient after a mean follow-up time of 11±6 months. No complications were noted. CONCLUSIONS: This preliminary study suggests that an 8-mm tip catheter may represent an alternative for RFA in patients with OTVEBs in whom a 4-mm tip was not successful. Larger randomized studies are therefore warranted.

Anatomical factors involved in difficult cardiac resynchronization therapy procedure: a non-invasive study using dual-source 64-multi-slice computed tomography.

AIMS: In cardiac resynchronization therapy (CRT) procedure, left ventricular (LV) lead implantation is time consuming. In this clinical setting, no study has investigated the impact of right atrium anatomical parameters on both CRT implantation procedure duration and X-ray exposure. Additionally, only few studies have examined the coronary sinus (CS) using dual-source 64-multi-slice computed tomography (DS 64-MSCT), and its impact on CRT procedure parameters has not yet been investigated. The aim of this prospective study was to identify local anatomical predictive factors of difficult CRT implantation procedure using DS 64-MSCT. METHODS AND RESULTS: Between January and July 2010, 50 consecutive patients underwent primo CRT implantation. The patient population had a mean age of 70 ± 10 years, and was 34% female, with New York Heart Association Class 3.2 ± 0.3 heart failure, left ventricle ejection fraction 30 ± 4%, and QRS width 157 ± 30 ms. Cardiac resynchronization therapy implantation was attempted in 50 patients, and first LV lead implantation was obtained in 49 of 50 patients (98% primary success). One implantation failed (2%) due to unsuccessful LV lead implant. Procedure parameters were as follows: LV threshold, 1.4 ± 0.8 V; LV wave amplitude, 17 ± 8 mV; LV impedance, 830 ± 240 Ω; median procedure time (skin to skin), 51 min (38 min); median fluoroscopy procedure time, 11.9 min (22 min); and median LV fluoroscopic time, 10.3 min (22 min). In 10 patients (20%), procedures were difficult requiring an implantation lasting ≥ 85 min. The only predictive factor for difficult CRT implantation was the insertion level of the CS ostium (CSO), evaluated by the distance between the CSO and the bottom floor of the right atrium (14.8 ± 4 vs. 9.5 ± 4; P= 0.01). Neither the right atrium dilation nor right ventricular dysfunction was associated with difficult CRT implantation procedures. CONCLUSIONS: Today, despite improvements in the materials used, problems still remain in the CRT procedure. In this clinical setting, the only predictive factor for very long CRT procedures is the CSO-level insertion (located high). This anatomical anomaly identified by DS 64-MSCT prior to surgery is responsible for 20% of difficult CRT device implantation procedures.

Predictive factors of difficult implantation procedure in cardiac resynchronization therapy.

AIMS: The usefulness of cardiac resynchronization therapy (CRT) in patients with congestive heart failure is offset by its long, user-dependent, and technical procedure. No studies have been published regarding factors related to CRT implantation procedure duration and X-ray exposure. Additionally, only a few studies have investigated the predictive factors of primary left ventricular (LV) lead implant failure. The aim of this prospective study was two-fold: (i) to evaluate the prevalence and predictive factors of prolonged CRT implantation procedure and (ii) to identify the predictive factors of primary LV lead implantation failure. METHODS AND RESULTS: Between November 2008 and September 2009, 128 consecutive patients underwent CRT implantation; of these, 22 patients (17.2%) were excluded because of CRT generator replacement. Population characteristics were a mean age of 69 +/- 10 years, 28.3% female, New York Heart Association class 3.2 +/- 0.3, LV ejection fraction (LVEF; 29 +/- 6%), and QRS width 146 +/- 23 ms. Cardiac resynchronization therapy implantation was attempted in 106 patients, and first LV lead implantation was obtained in 96 of 106 patients (90.5% primary success). Ten primary implantations failed (9.5%), due to unsuccessful LV lead implants. A second procedure was successfully attempted in six patients with a second more experienced operator (5.7%). Among the remaining four patients, one patient required a surgical epicardial LV lead implantation, and the implantation was not reattempted in the other three patients. The overall success rate of CRT system implantation was 96.2% (102 of 106 patients). Procedure parameters were as follows: LV threshold (1.4 +/- 0.9 V); LV wave amplitude (15 +/- 8 mV); LV impedance (874 +/- 215 ohm); median procedure time (skin to skin), 55 min (45-80); and median of procedure fluoroscopy time, 11 min (6.2-29). In 24 patients (22.6%), difficult procedures requiring >or=85 min of implantation duration occurred. By univariate analysis, predictive factors of difficult implantation were LV ejection fraction (25.6 +/- 6 vs. 30.2 +/- 8%; P = 0.02), LV end-diastolic diameter (72.4 +/- 11 vs. 66 +/- 11 mm; P = 0.01), LV end-systolic diameter (LVESD; 62 +/- 12 vs. 56 +/- 12 mm, P = 0.04), and the operator's experience (very experienced operator vs. less experienced operator, P = 0.006). By multivariate analysis, only primary LV lead implantation failure, LVESD, and operator's experience were independently associated with difficult procedures. In this patient subset with primary LV lead implant failure (n = 10), the only independent predictive factor was the LV end-systolic volume (P = 0.03). CONCLUSION: In this study, the rate of difficult CRT device implantation procedures approached 25%. Both the degree of LV dysfunction and the operator's experience were independent predictors of surgical difficulties. Left ventricular end-systolic volume was the only independent predictor of primary LV lead implant failure.

Prevalence and risk factors related to infections of cardiac resynchronization therapy devices.

AIMS: Device-related infections (DRI) are not well understood in patients implanted with a cardiac resynchronization therapy (CRT) device. The aims of this study were: (i) to evaluate the prevalence of CRT DRI; (ii) to establish the factors predictive of CRT DRI. METHODS AND RESULTS: Between January 2001 and May 2007, CRT implantation was performed in 303 patients (247 men, 82%). The mean follow-up was 31 +/- 19 months. Population characteristics were a mean age of 70 +/- 10 years old; 56 female; aetiology includes (202 dilated and 101 ischaemic cardiomyopathy); NYHA class 3.2 +/- 0.3; LVEF (26 +/- 6%), and a QRS width of 171 +/- 31 ms. Thirteen patients developed a DRI: endocarditis in four, pocket erosion in three, pocket abscess in five, and septicaemia in one. The prevalence of DRI was 4.3%. By univariate analysis, predictive factors of DRI were: procedure time (skin to skin: median of 85 vs. 57.5 min; P = 0.03), re-intervention (54 vs. 6.5%; P < 0.0001), haematoma (31 vs. 8.6% P = 0.01), lead dislodgement (23 vs. 6.2%; P = 0.03), dialysis (23.1 vs. 1.72%; P = 0.003), and procedure type [CRT-ICD (8.6%) vs. CRT PM (1.6%) or system up-grade (1.5%); P = 0.03]. Significant correlations were found between re-intervention and lead dislodgement (r = 0.8; P < 0.001), haematoma (r = 0.2; P < 0.001). Four independent predictive factors of DRI were identified as procedure time (P = 0.002); dialysis (P = 0.0001); re-intervention (P = 0.006), and procedure type (CRT-ICD vs. other procedures; P = 0.01). CONCLUSION: This study found that the prevalence of CRT DRI is close to 4.3% at 2.6 years (1.7% per year incidence). Four independent predictive factors of infections were identified including re-intervention, procedure time, dialysis, and primo CRT-ICD implantation. These parameters should be part of the risk-benefit evaluation in patients selected for CRT implantation.

Radiofrequency catheter selection based on cavotricuspid angiography compared with a control group with an externally cooled-tip catheter: a randomized pilot study.

BACKGROUND: Radiofrequency ablation (RFA) of cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) can be performed using either externally cooled-tip RFA catheters or large-tip (8 mm) catheters. However, experimental and clinical studies suggest that the efficacy of both catheters may vary with CTI anatomy and catheters orientation. OBJECTIVES: The aim of this prospective study was to evaluate: a RFA catheter selection based on CTI angiography compared with a control group with an externally cooled-tip catheter together with the risk of an expensive crossover catheter in both groups. METHOD: Over a period of 16 months, 119 patients were included and randomized. RESULTS: When comparing the angiographic group (n = 56) and the externally cooled-tip RFA catheter group (n = 63), the duration of application time with a median of 7 min (interquartile range 4.5-11) versus a median of 10 min (interquartile range 6-20; P = 0.008) and the duration of X-ray exposure with a median of 7 min (interquartile range 4-10) versus a median of 10 min (interquartile range 5-15; P = 0.025) were significantly lower in the angiographic group versus externally cooled-tip catheter group. Furthermore, the number of catheters crossover was significantly higher in the angiographic group versus externally cooled-tip catheter group I (27% vs 7%; P = 0.007). CONCLUSIONS: This study shows that a strategy with a catheter selection based on a CTI angiographic evaluation is superior to an empirical use of an externally cooled-tip catheter during CTI RFA. Thus, angiographic isthmus evaluation predicts the effectiveness of a RFA catheter and the risk of an expensive catheter crossover.