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BACKGROUND: Patients with congenital heart defects (CHD) are prone to residua, sequels and complications from the underlying anomaly, where cardiac arrhythmias are one of the major causes for hospitalization, morbidity and mortality. The importance of the subcutaneous implantable loop recorder (ILR) for the detection and documentation of significant arrhythmias has increased over the last years. To date, however, there is little data on ILR use in the CHD population. METHODS: In this single center, retrospective observational study, all CHD-patients with an ILR were identified who were under care of the German Heart Center Munich between February 2015 and January 2019. The primary endpoint of the study was the detection or exclusion of significant arrhythmias during follow-up in CHD-patients who had received an ILR. The secondary endpoint was to determine whether ILR findings influenced patient management, defined as initiation or adjustment of medication, cardioversion, electrophysiologic study, catheter ablation, or implantation of cardiac implantable electronic devices (CIEDs) such as pacemakers (PM) or implantable cardioverter-defibrillators. RESULTS: An ILR was implanted in 33 CHD-patients (mean age, 43±20 years; 42.4% female) with CHD. During a mean observation period of 697±433 days, clinically relevant arrhythmias, correlating with the patients’ complaints and symptoms, were detected in 19 patients (59.4%), encompassing supraventricular tachycardia (n=10), supraventricular or ventricular ectopic beats (n=10), non-sustained ventricular tachycardia (n=2), ventricular tachycardia (n=2), and bradycardia (n=2). In 9 patients (28.1%) the detected arrhythmia was considered an event requiring treatment. Treatment modalities included catheter ablation (n=5), modification of antiarrhythmic drug regime (n=2), adaptation of anticoagulation therapy (n=2), or implantation of a subcutaneous ICD (n=1). Regarding the occurrence of cardiac arrhythmias or a related need for therapeutic intervention, no significant differences were identified with respect to WHO functional class, the presence of pulmonary arterial hypertension or reduced resting peripheral oxygen saturation. CONCLUSIONS: In symptomatic CHD-patients at risk for life-threatening cardiac events, ILR has a considerable complementary diagnostic value for the detection and differentiation of benign and malignant arrhythmias. Considering the overall low risk of complications, ILR implantation should be considered in patients with CHD of any complexity who need medium or long-term arrhythmia monitoring, especially if short-term Holter monitoring cannot provide sufficient diagnostic certainty.

Aim To evaluate whether left bundle branch block with residual conduction (rLBBB) is associated with worse outcomes after cardiac resynchronisation therapy (CRT). Methods All consecutive CRT implants at our institution between 2006 and 2013 were identified from our local device registry. Pre- and post-implant patient specific data were extracted from clinical records. Results A total of 690 CRT implants were identified during the study period. Prior to CRT, 52.2% of patients had true left bundle branch block (LBBB), 19.1% a pacing-induced LBBB (pLBBB), 11.2% a rLBBB, 0.8% a right bundle branch block (RBBB), and 16.5% had a nonspecific intraventricular conduction delay (IVCD) electrocardiogram pattern. Mean age at implant was 67.5 years (standard deviation [SD] = 10.6), mean left ventricular ejection fraction (LV EF) was 25.7% (SD = 7.9%), and mean QRS duration was 158.4 ms (SD = 32 ms). After CRT, QRS duration was significantly reduced in the LBBB (p, This retrospective study examined CRT response and mortality of patients with rLBBB, in comparison to patients with true LBBB. The groups did not exhibit any significant difference in post-CRT LV EF or mortality. Predictors of mortality post-CRT include post-CRT LV EF, presence of CKD, and older age at implant.

This study was designed to evaluate the electromagnetic interference (EMI) effects and safety of the new security screening millimetre wave body scanners (MWBSs) for patients with rare cardiac implantable electronic devices (CIEDs). We identified 73 patients with either entirely subcutaneous implantable cardioverter-defibrillators (S-ICD) or leadless pacemakers (LPM) attending routine device follow-up. CIED programming was optimised for the detection of EMI occurrence, and high-voltage therapy was disabled. Patients then underwent millimetre wave body scans under continuous ECG monitoring. Scanning was performed at the recommended distance as well as in close proximity to the scanner emulating accidental exposure. CIED function was observed for EMI effects. There were no episodes of inhibition of pacing in the leadless pacemaker subgroup, no oversensing in the S-ICD subgroup and no spontaneous device reprogramming in any group. There was no change in pacing or sensing thresholds, and S-ICD vector eligibility remained unchanged after scanning with the MWBS. No CIEDs were identified by the MWBS during the study. No EMI events were detected during the use of MWBSs by patients with either S-ICDs or LPMs. This data should be reassuring for patients suggesting that they can undergo security body scans without worries or disclosure of their CIED status.

Die kardiale Resynchronisationstherapie (CRT) stellt eine Standardbehandlung der symptomatischen, therapierefraktaren Herzinsuffizienz dar. Dennoch betragt die Rate an Non-Respondern rund 30 %. Die Bildung von simultanen Erregungsfronten im linksventrikularen Myokard mittels multipolarer Stimulation (MPP) konnte bei Respondern die Effektivitat der CRT verbessern oder die Zahl der Non-Responder reduzieren.

Catheter ablation is an effective treatment for atrial fibrillation (AF). Obstructive sleep apnea (OSA) is a known risk factor for recurrent AF. The apnea-hypopnea index (AHI) is a measurement tool to screen patients for OSA. We sought to evaluate if the ambulatory assessed AHI is associated with AF recurrence following AF catheter ablation. 187 patients with paroxysmal (n = 155) or early persistent (n = 32) AF presenting for catheter ablation were included in the study. AHI was determined prior to ablation using an ambulatory screening device. All patients underwent pulmonary vein isolation (PVI). In patients with early persistent AF (17%) additional ablation of complex fractionated atrial electrograms (CFAE) was performed. Clinical follow-up was available after 3 and 12 months including 7-day Holter-ECG. All 187 patients (60.3 ± 11.4 years, 64.2% male) completed the 3 months follow-up and 170 patients the 12 months follow-up. A pathological AHI ≥15 was found in 45/187 (24.1%) patients. Additional CFAE did not differ between patients with an AHI ≥15 and AHI15 (p = 0.663). After 3 months, 12/41 (29.3%) patients with AHI ≥15 showed recurrent AF compared to 24/146 (16.4%) patients with AHI15 (p = 0.066). After 12 months, AHI ≥15 was associated with a significant higher rate of AF recurrence of 47.4% (18/38) versus 26.5% (35/132) in patients with AHI15 (p = 0.014). In the logistic regression analysis AHI ≥15 was an independent predictor of recurrent AF at 12 months (p = 0.011). In conclusion, ambulatory assessed AHI ≥15 is associated with increased risk for AF recurrence following catheter ablation. OSA screening should be performed in AF patients as it might influence catheter ablation success.

Therapy of choice for the primary and secondary prevention of sudden cardiac death is the implantation of an implantable cardioverter defibrillator (ICD). Whereas appropriate and inappropriate ICD shocks lead to myocardial microdamage, this is not known for antitachycardia pacing (ATP). In total, 150 ICD recipients (66 ± 12 years, 81.3% male, 93.3% primary prevention, 30.0% resynchronization therapy) were randomly assigned to an ICD implantation with or without intraoperative ATP. In the group with ATP, the pacing maneuver was performed twice, each time applying 8 impulses à 6 Volt x 1.0 milliseconds to the myocardium. High sensitive Troponin T (hsTnT) levels were determined prior to the implantation and thereafter. There was no significant difference in the release of hsTnT between the two randomization groups (delta TnT without ATP in median 0.010 ng/ml [min. −0.016 ng/ml–max. 0.075 ng/ml] vs. with ATP in median 0.013 ng/ml [min. −0.005–0.287 ng/ml], p = 0.323). Setting a hsTnT cutoff of 0.059 ng/dl as a regularly augmented postoperative hsTnT level, no relevant difference between the two groups regarding the postoperative hsTnT levels above this cutoff could be identified (without ATP n = 10 [14.7%] vs. with ATP n = 16 [21.9%], p = 0.287). There was no significant difference in the release of high sensitive Troponin between patients without intraoperative ATP compared to those with intraoperative ATP. Hence, antitachycardia pacing does not seem to cause significant myocardial microdamage. This may further support its use as a painless and efficient method to terminate ventricular tachycardia in high-risk patients.

Many patients receiving cardiac resynchronization therapy (CRT) suffer from permanent atrial fibrillation (AF). Knowledge of the atrial rhythm is important to direct pharmacological or interventional treatment as well as maintaining AV-synchronous biventricular pacing if sinus rhythm can be restored. A single pass single-coil defibrillator lead with a floating atrial bipole has been shown to obtain reliable information about the atrial rhythm but has never been employed in a CRT-system. The purpose of this study was to assess the feasibility of implanting a single coil right ventricular ICD lead with a floating atrial bipole and the signal quality of atrial electrograms (AEGM) in CRT-defibrillator recipients with permanent AF. Methods and results: Seventeen patients (16 males, mean age 73 ± 6 years, mean EF 25 ± 5%) with permanent AF and an indication for CRT-defibrillator placement were implanted with a designated CRT-D system comprising a single pass defibrillator lead with a atrial floating bipole. They were followed-up for 103 ± 22 days using remote monitoring for AEGM transmission. All patients had at last one AEGM suitable for atrial rhythm diagnosis and of 100 AEGM 99% were suitable for visual atrial rhythm assessment. Four patients were discharged in sinus rhythm and one reverted to AF during follow-up. Conclusion: Atrial electrograms retrieved from a single-pass defibrillator lead with a floating atrial bipole can be reliably used for atrial rhythm diagnosis in CRT recipients with permanent AF. Hence, a single pass ventricular defibrillator lead with a floating bipole can be considered in this population. Keywords: Cardiac resynchronization therapy, Heart failure, Atrial fibrillation, Remote monitoring, Atrial sensing, Defibrillator

Telemonitoring eignet sich besonders zur Fruherkennung von Sondenfehlfunktionen und zur Vermeidung inadaquater Defibrillatortherapien. Subklinisches Vorhofflimmern kann mittels Telemonitoring zuverlassig erfasst werden, sodass eine Antikoagulationsbehandlung bei Risikopatienten initiiert werden kann. Die engmaschige Uberwachung von Herzinsuffizienzpatienten hat das Potenzial, die Mortalitat der Patienten zu reduzieren.

There is a rising prevalence of patients with cardiac implantable electronic devices (CIEDs) as a result of an increasing implantation rate (worldwide >1 million/year), and many of these patients will undergo security screening for travel during their life ([1][1]). CIEDs are vulnerable to

Background Electric cars are increasingly used for public and private transportation and represent possible sources of electromagnetic interference (EMI). Potential implications for patients with cardiac implantable electronic devices (CIED) range from unnecessary driving restrictions to life-threatening device malfunction. This prospective, cross-sectional study was designed to assess the EMI risk of electric cars on CIED function. Methods One hundred and eight consecutive patients with CIEDs presenting for routine follow-up between May 2014 and January 2015 were enrolled in the study. The participants were exposed to electromagnetic fields generated by the four most common electric cars (Nissan Leaf, Tesla Model S, BMW i3, VW eUp) while roller-bench test-driving at Institute of Automotive Technology, Department of Mechanical Engineering, Technical University, Munich. The primary endpoint was any abnormalities in CIED function (e.g. oversensing with pacing-inhibition, inappropriate therapy or mode-switching) while driving or charging electric cars as assessed by electrocardiographic recordings and device interrogation. Results No change in device function or programming was seen in this cohort which is representative of contemporary CIED devices. The largest electromagnetic field detected was along the charging cable during high current charging (116.5 μT). The field strength in the cabin was lower (2.1-3.6 μT). Conclusions Electric cars produce electromagnetic fields; however, they did not affect CIED function or programming in our cohort. Driving and charging of electric cars is likely safe for patients with CIEDs.

To determine the current incidence of antitachycardia therapy suspension due to magnet reversion in patients with implantable cardioverter defibrillators (ICDs). From March 2012 to September 2018, all St. Jude Medical ICD interrogations performed at the Deutsches Herzzentrum Munchen were screened for stored events of antitachycardia therapy suspension caused by static magnetic fields (flux densities ≥ 1 mT as defined in St. Jude Medical ICDs) affecting the giant magnetoresistance (GMR) sensor. Intentional ICD deactivation or inappropriate magnet application in the hospital was classified as non-environmental electromagnetic interference (EMI) whereas in the case of any other stored magnet reversion, the event was classified as presumably environmental EMI. Data from 201 St. Jude Medical ICD patients (mean age 62 ± 24 years, 165 males/36 females) were included in the analysis. ICD interrogations occurred at a mean follow-up of 25.1 months ± 15.6 months and summed up to a total of 464 patient-years of follow-up. A total number of 43 magnet reversion events were detected in 21 patients. Thirty-two events in 13 patients were presumably related to environmental EMI sources. Suspension of antitachycardia therapy only occurred in a temporary fashion. None of the patients experienced any ventricular tachyarrhythmia during ICD inhibition. The incidence of antitachycardia therapy suspension due to magnet reversion related to presumably environmental EMI sources was 6.9% per patient and year. Although none of the patients experienced any harmful event, antitachycardia therapy suspension due to magnet reversion is a common issue. Patients should be well-educated about potential EMI sources as well as trained in handling them.

This joint consensus paper of the German Roentgen Society and the German Cardiac Society provides physical and electrophysiological background information and specific recommendations for the procedural management of patients with cardiac pacemakers (PM) and implantable cardioverter defibrillators (ICD) undergoing magnetic resonance (MR) imaging. The paper outlines the responsibilities of radiologists and cardiologists regarding patient education, indications, and monitoring with modification of MR sequences and PM/ICD reprogramming strategies being discussed in particular. The aim is to optimize patient safety and to improve legal clarity in order to facilitate the access of SM/ICD patients to MR imaging. Key Points: Citation Format

Der subkutane implantierbare Kardioverter-Defibrillator (S-ICD) ist eine etablierte Therapie zur Pravention des plotzlichen Herztods. Auf Grund seines Detektionsalgorithmus ist er jedoch ganz wesentlich auf eine korrekte Morphologieerkennung des QRS-Komplexes angewiesen, ohne dass es zu einer zusatzlichen Wahrnehmung der T‑Welle kommt. In diesem Zusammenhang wird uber einen Patienten berichtet, bei dem wegen eines neu aufgetretenen Rechtsschenkelblocks ein T‑Wellen-Oversensing zu inadaquaten Schocks gefuhrt hat. Nachfolgend werden Moglichkeiten zur optimalen Gerateprogrammierung diskutiert.

For physicians involved in the treatment of patients with implantable cardioverter-defibrillators (ICDs) the knowledge of tachycardia detection algorithms is of paramount importance. This knowledge is essential for adequate device selection during de-novo implantation, ICD replacement, and for troubleshooting during follow-up. This review describes tachycardia detection algorithms incorporated in ICDs by Sorin/LivaNova and analyses their strengths and weaknesses.

Die Schrittmacher- und Defibrillatortherapie ist als sichere Behandlung von bradykarden bzw. tachykarden Rhythmusstorungen etabliert. Trotz korrekter Sonden- und Geratefunktion sowie adaquater Programmierung konnen die Aggregate durch elektromagnetische Felder gestort werden. Im folgenden Artikel soll auf mogliche Storquellen mit sachlicher Risikobewertung und mogliche Vermeidungsstrategien hingewiesen werden. Die weit verbreiteten Sorgen hinsichtlich bedrohlicher Beeintrachtigungen der Implantate sollen genommen werden.

Patients with persistent atrial fibrillation (AF) may additionally suffer from a concealed sinus node disease. We sought to determine the incidence, indications and predictors of acute pacemaker [PM] implantation within 1 week after the ablation of persistent AF. We performed a retrospective analysis of patients, who had had an ablation of persistent AF at our center. Between 01/2011 and 08/2016, 1234 patients (mean age 65 ± 10 years, 66.7% male) without prior PM implantation underwent an ablation of persistent AF. Pulmonary vein isolation (PVI) was performed in 1158 (93.8%), the additional ablation of complex fractionated atrial electrograms (CFAE) in 1109 (89.9%) and linear ablation in 524 (42.5%) patients. Temporary cardiac pacing was necessary in 27 (2.2%) patients. The temporary PM was removed in 15 patients (1.2%) because sinus node recovered after a median of 1.0 (minimum 0.1−maximum 2.0) day. The remaining 12 (1.0%) patients required the implantation of a permanent PM. Another 13 (1.1%) patients required permanent PM implantation without prior temporary pacing. In a multivariable regression model, age [OR 1.07 (1.02–1.12), p = 0.006], sinus pauses prior to ablation [OR 7.97 (2.36–26.88), p = 0.001] and atria with low voltage [OR 2.83 (1.31–6.11), p = 0.008] were identified as significant predictors for acute cardiac pacing. Acute cardiac pacing within 1 week after the ablation of persistent AF was necessary in 40 (3.2%) patients. Age, sinus pauses in history prior to ablation and the existence of low-voltage areas in the atria were identified as relevant risk factors.

Fixation of the pacemaker leads during pacemaker implantation leads to an increase of cardiac Troponin T (cTnT) that can be interpreted as a sign of minimal myocardial damage. This trial evaluates whether the mechanism type of lead fixation influences the magnitude of cTnT release. Patients having a de-novo cardiac pacemaker implantation or a lead revision were centrally randomized to receive either a ventricular lead with an active (screw) or passive (tine) fixation mechanism. High-sensitive Troponin T (hsTnT) was determined on the day of the procedure beforehand and on the following day. 326 Patients (median age (IQR) 75.0 (69.0–80.0) years, 64% male) from six international centers were randomized to receive ventricular leads with an active (n = 166) or passive (n = 160) fixation mechanism. Median (IQR) hsTnT levels increased by 0.009 (0.004–0.021) ng/ml in the group receiving screw-in ventricular leads and by 0.008 (0.003–0.030) ng/ml in the group receiving tined ventricular leads (n.s.). In conclusion pacemaker implantations are followed by a release of hsTnT. The choice between active or passive fixation ventricular leads does not have a significant influence on the extent of myocardial injury and the magnitude of hsTnT release.

Cardiac resynchronization therapy (CRT) is standard of care in heart failure (HF), however this technique is associated with a non-responder rate of 30%. Multipole pacing (MPP) with a quadripolar lead may optimize CRT and responder rate by creating two electrical wave fronts in the left ventricular (LV) myocardium simultaneously in order to reduce mechanical dyssynchrony. The objective of this study was to investigate the acute impact of MPP on LV function by assessing systolic dyssynchrony index (SDI) and left ventricular ejection fraction (LVEF) via real-time three-dimensional echocardiography (RT3DE).In 41 consecutive patients (87.8% male; mean age 66.0 ± 12.7 years) who received CRT defibrillators with a quadripolar LV lead, RT3DE datasets were acquired the day after implantation under the following pacing configurations: Baseline AAI, conventional biventricular pacing using distal or proximal LV poles and MPP. Datasets were analyzed in paired samples evaluating SDI and LVEF depending on programmed pacing modality.MPP resulted in statistically significant reduction of SDI compared to baseline (6.3%; IQR 4.4-7.8 and 9.9%; IQR 8.0-12.7; p 0.001) and to conventional biventricular pacing using distal (7.6%; IQR 6.5-9.1; p 0.001) or proximal (7.4%; IQR 6.2-8.8; p 0.001) LV poles respectively. MPP yielded significant increase in LVEF compared to baseline (30.6%; IQR 25.8-37.5 and 27.2%; IQR 21.1-33.6; p 0.001) and to conventional biventricular pacing configuration with distal (28.1%; IQR 22.1-34.5; p 0.001) or proximal (28.6%; IQR 23.2-34.9; p 0.001) LV poles respectively.Multipole pacing improves mechanical dyssynchrony of the left ventricular myocardium as assessed by SDI and LVEF.

Purpose Electromagnetic interference (EMI) with implantable cardioverter defibrillators (ICDs) can cause oversensing and subsequently inappropriate ICD therapies. We retrospectively investigated the current incidence and clinical relevance of oversensing related EMI in a large cohort of ICD patients. Methods From January 2005 to April 2013, all ICD interrogations performed at our institution were analyzed for the occurrence of oversensing related EMI. EMI episodes were classified as clinically significant, potentially significant or of minor significance. To identify risk factors for EMI, we also analyzed different lead models in our cohort (integrated vs true bipolar leads). Results Data of 2940 ICD patients (mean age 63 ± 16 years, 2322 male patients, 7772 patient-years) were retrospectively analyzed for the occurrence of EMI. During the observation period, a total of 145 (hospital environment n = 97, non-hospital environment n = 48) episodes occurred and resulted in an overall EMI incidence, i.e. event rate, of 1.87 % per patient per year. Focusing on clinically significant or potentially significant episodes, the EMI incidence was 0.27 % per patient per year. Cox proportional hazards regression analysis did not reveal a statistically significant higher hazard of oversensing for patients with integrated bipolar leads compared to patients with true bipolar leads (HR = 2.21; 95 % CI 0.90-5.39; p = 0.083). Conclusions Our data demonstrate that EMI continues to occur in everyday life. Patients should be well informed about the potential sources and risks of EMI but they need not be overly concerned since the risk of EMI-especially in a non-hospital environment-is low.

Background The impact of right ventricular (RV) lead location on clinical end points in patients undergoing cardiac resynchronization therapy (CRT) is unclear. We evaluated the impact of different RV lead locations on clinical outcome in CRT patients enrolled in the Septal Positioning of ventricular implantable cardioverter-defibrillator (ICD) Electrodes (SPICE) trial, which randomized recipients of implantable cardioverter defibrillators to apical versus midseptal RV lead positioning. Methods Ninety-eight CRT recipients were included in the multicenter SPICE trial and followed for 12 months: Fifty-three patients were randomized to receive an apical (A) and 45 to receive a midseptal (S) lead position. We compared echocardiographical and electrocardiographical parameters and outcome. Results Echocardiographic response with respect to improvement of left ventricular ejection fraction (A: +15.8 ± 14.6%, S: +9.7 ± 12.6%, P = 0.156) and reduction of left ventricular end-diastolic diameter (A: −4.2 ± 10.7 mm, S: −7.5 ± 10.7 mm, P = 0.141) was comparable in apical and midseptal groups. Paced QRS width neither differed at prehospital discharge (A: 129 ± 21 ms, S: 135 ± 21 ms, P = 0.133) nor at 12-month follow-up (A: 131 ± 23 ms, S: 134 ± 28 ms, P = 0.620). No differences were found with respect to the risk of ventricular tachyarrhythmia or ICD therapy. Septal RV lead position, however, was associated with a significant longer time to a first heart failure event (P = 0.040) and a longer survival time (P = 0.019). Conclusions In CRT recipients, midseptal RV lead position was not superior with respect to improvement of echocardiographic parameters or paced QRS width. It did not predispose to ventricular arrhythmias or ICD therapy. The finding that midseptal lead position was associated with a longer time to first heart failure event and a longer survival time deserves further investigation.

Accuracy of Contact-Force SensingBackground Contact-force (CF) sensing catheters are increasingly used in clinical electrophysiological practice due to their efficacy and safety profile. As data about the accuracy of this technology are scarce, we sought to quantify accuracy based on in vitro experiments. Methods and Results A custom-made force sensor was constructed that allowed exact force reference measurements registered via a flexible membrane. A Smarttouch Surround Flow (ST SF) ablation catheter (Biosense Webster, Diamond Bar, CA, USA) was brought in contact with the membrane of the force sensor in order to compare the ST SF force measurements to force sensor reference measurements. ST SF force sensing technology is based on deflection registration between the distal and proximal catheter tip. The experiment was repeated for n = 10 ST SF catheters, which showed no significant difference in accuracy levels. A series of measurements (n = 1200) was carried out for different angles of force acting to the catheter tip (0°/perpendicular contact, 30°, 60°, 90°/parallel contact). The mean absolute differences between reference and ST SF measurements were 1.7 ± 1.8 g (0°), 1.6 ± 1.2 g (30°), 1.4 ± 1.3 g (60°), and 6.6 ± 5.9 g (90°). Measurement accuracy was significantly higher in non-parallel contact when compared with parallel contact (P < 0.01). Conclusions Catheter force measurements using the ST SF catheters show a high level of accuracy regarding differences to reference measurements and reproducibility. The reduced accuracy in measurements of 90° acting forces (parallel contact) might be clinically important when creating, for example, linear lesions.

Transseptal Puncture Guided by 3D-Fluoroscopy Background Transseptal puncture for left atrial (LA) access is still mainly performed using fluoroscopy and transesophageal or intracardiac echocardiography. We present an easily applicable approach for the guidance of transseptal puncture that uses the combination of a 3D-mapping system and CT-derived 3D-overlayed anatomy. Methods and Results A computer tomographic (CT) LA-angiography was performed in n = 65 patients prior to a scheduled atrial fibrillation ablation procedure. The CARTO3® (Biosense Webster, Diamond Bar, CA, USA) segmentation tool was used to create a 3D-reconstruction of cardiac anatomy and the spine. The CARTO UNIVU® module was then used to overlay and register the segmented 3D-anatomy onto fluoroscopy. The 3D-reconstructed spine and cardiac anatomy were congruently aligned to their fluoroscopic counterparts in fluoroscopic views. The feasibility of the technique, its safety, and accuracy (assessed as contour offsets between 3D-overlay and angiographic LA anatomy) were evaluated. Overlay registration accuracy was analyzed by CARTO3® registration matrices. Transseptal puncture was feasible without complications in all 65 patients using the new 3D-overlay technique. Three-dimensional-overlay contour offsets were 1.6 ± 1.2 mm in left PV, 1.7 ± 1.2 mm in right PV, and 1.3 ± 1.0 mm in the LA roof region. Overlay registration accuracy was 4.9 ± 2.7 mm. The average time needed for anatomy segmentation was 204 ± 61 seconds, time needed for overlay registration was 18 ± 8 seconds. Conclusions Three-dimensional-augmented fluoroscopy is feasible, safe, and easy to apply as guidance for transseptal puncture and demonstrates a high level of accuracy.

Aims This study presents and evaluates the impact of a new lowest-dose fluoroscopy protocol (Siemens AG), especially designed for electrophysiology (EP) procedures, on X-ray dose levels. Methods and results From October 2014 to March 2015, 140 patients underwent an EP study on an Artis zee angiography system. The standard low-dose protocol was operated at 23 nGy (fluoroscopy) and at 120 nGy (cine-loop), the new lowest-dose protocol was operated at 8 nGy (fluoroscopy) and at 36 nGy (cine-loop). Procedural data, X-ray times, and doses were analysed in 100 complex left atrial and in 40 standard EP procedures. The resulting dose–area products were 877.9 ± 624.7 µGym² ( n = 50 complex procedures, standard low dose), 199 ± 159.6 µGym² ( n = 50 complex procedures, lowest dose), 387.7 ± 36.0 µGym² ( n = 20 standard procedures, standard low dose), and 90.7 ± 62.3 µGym² ( n = 20 standard procedures, lowest dose), P < 0.01. In the low-dose and lowest-dose groups, procedure times were 132.6 ± 35.7 vs. 126.7 ± 34.7 min ( P = 0.40, complex procedures) and 72.3 ± 20.9 vs. 85.2 ± 44.1 min ( P = 0.24, standard procedures), radiofrequency (RF) times were 53.8 ± 26.1 vs. 50.4 ± 29.4 min ( P = 0.54, complex procedures) and 10.1 ± 9.9 vs. 12.2 ± 14.7 min ( P = 0.60, standard procedures). One complication occurred in the standard low-dose and lowest-dose groups ( P = 1.0). Conclusion The new lowest-dose imaging protocol reduces X-ray dose levels by 77% compared with the currently available standard low-dose protocol. From an operator standpoint, lowest X-ray dose levels create a different, reduced image quality. The new image quality did not significantly affect procedure or RF times and did not result in higher complication rates. Regarding radiological protection, operating at lowest-dose settings should become standard in EP procedures.

Accuracy of MediGuide® Navigation Background Data about localization reproducibility as well as spatial and visual accuracy of the new MediGuide® sensor-based electroanatomic navigation technology are scarce. We therefore sought to quantify these parameters based on phantom experiments. Methods and Results A realistic heart phantom was generated in a 3D-Printer. A CT scan was performed on the phantom. The phantom itself served as ground-truth reference to ensure exact and reproducible catheter placement. A MediGuide® catheter was repeatedly tagged at selected positions to assess accuracy of point localization. The catheter was also used to acquire a MediGuide®-scaled geometry in the EnSite Velocity® electroanatomic mapping system. The acquired geometries (MediGuide®-scaled and EnSite Velocity®-scaled) were compared to a CT segmentation of the phantom to quantify concordance. Distances between landmarks were measured in the EnSite Velocity®- and MediGuide®-scaled geometry and the CT dataset for Bland–Altman comparison. The visualization of virtual MediGuide® catheter tips was compared to their corresponding representation on fluoroscopic cine-loops. Point localization accuracy was 0.5 ± 0.3 mm for MediGuide® and 1.4 ± 0.7 mm for EnSite Velocity®. The 3D accuracy of the geometries was 1.1 ± 1.4 mm (MediGuide®-scaled) and 3.2 ± 1.6 mm (not MediGuide®-scaled). The offset between virtual MediGuide® catheter visualization and catheter representation on corresponding fluoroscopic cine-loops was 0.4 ± 0.1 mm. Conclusions The MediGuide® system shows a very high level of accuracy regarding localization reproducibility as well as spatial and visual accuracy, which can be ascribed to the magnetic field localization technology. The observed offsets between the geometry visualization and the real phantom are below a clinically relevant threshold.

Background The impact of the CartoUnivu™ technology (Biosense Webster, Diamond Bar, CA, USA) on fluoroscopy exposure compared to a conventional approach using electroanatomical mapping (Carto 3™) was evaluated in patients undergoing radiofrequency ablation for ventricular tachyarrhythmias (VT). Methods and Results We prospectively evaluated 23 patients undergoing VT ablation using the CartoUnivu™ technology. The CartoUnivu™ Module integrates fluoroscopic images and cine loops into the electroanatomical mapping system. As a control group, 23 out of 88 VT patients (ablated using conventional fluoroscopy supplemented by electromagnetic mapping with the Carto 3™ System) were matched for age, gender, body surface area, operator, redo-procedure, presence of coronary artery disease, and left ventricular dysfunction using propensity score matching. A significant reduction in fluoroscopy exposure was observed in the CartoUnivu™ group when compared to the conventional group (10.57 ± 7.93 minutes vs 18.52 ± 11.24 minutes, P_= 0.008; 611 cGy/cm2 vs 1650 cGy/cm2, P = 0.001). In multivariate analysis, the CartoUnivu™ module was an independent predictor of reduced fluoroscopy use. Conclusion This is a report on the clinical application of the CartoUnivu system for VT ablation. CartoUnivu™ markedly reduced fluoroscopy time and dose compared to conventional fluoroscopy/electroanatomical mapping.

Die MADIT-RIT-Studie stellt eine der bedeutendsten Studien zu implantierbaren Kardioverter-Defibrillatoren (ICD) der letzten Jahre dar. Sie stellt in besonderer Weise heraus, dass unterschiedliche Programmierstrategien (hohe Detektionsfrequenz oder verzogerte Therapie vs. konventionelle Einstellung) die Haufigkeit inadaquater ICD-Therapien reduziert, das Synkopenrisiko unverandert belasst und zu einem verbesserten Patientenuberleben fuhren kann. Die Studie sollte alle Kardiologen und Elektrophysiologen dazu anhalten, ihre gegenwartigen Programmierstrategien kritisch zu hinterfragen. Allerdings wurden in die Studie v. a. Patienten mit ischamischer oder dilatativer Kardiomyopathie eingeschlossen, die zur Primarprophylaxe des plotzlichen Herztods einen Zweikammer-ICD oder ein ICD zur Resynchronisationstherapie erhalten haben, und es konnen die Ergebnisse der Studie nicht unbedingt auf andere Krankheitsbilder und andere Geratearten ubertragen werden. Trotz des Erfolgs der MADIT-RIT-Studie sind weitere Anstrengungen erforderlich, um die ICD-Algorithmen zur Arrhythmiedetektion weiter zu verbessern und inadaquate Therapien zu minimieren. Eine optimierte ICD-Therapie schliest zudem die Vermeidung von unnotigen Schocks und die Behandlung aller anderen Aspekte der kardialen Grunderkrankung mit ein.

Patients with pacemakers or implantable cardioverter defibrillators (ICDs) are advised to keep mobile phones at least 6 inches (15 cm) away from these devices to avoid electromagnetic interference. This is because electromagnetic fields emitted by phones can be misinterpreted as intrinsic cardiac

Atrial fibrillation (AF) is a relevant comorbidity in recipients of implantable cardioverter-defibrillators (ICD). Latest generation single-chamber ICD allow the additional sensing of atrial tachyarrhythmias and, therefore, contribute to the early detection and treatment of AF, potentially preventing AF-related stroke. The present study aimed to measure the impact on patient-related costs of this new ICD compared to conventional ICD. A Markov model was developed to simulate the long-term incidence of stroke in patients treated with a single-chamber ICD with or without atrial sensing capabilities. The median annual cost per patient and its difference, the number of strokes avoided, and the cost per stroke avoided were estimated. During a 9-year horizon, the costs for the ICD and stroke treatment were €570 per patient-year for an ICD with atrial sensing capabilities and €491 per patient-year for a conventional ICD. Per 1,000 patients, 4.6 strokes per year are assumed to be avoided by the new device. Higher CHA2DS2-VASc scores are associated with higher numbers of avoided strokes and larger potential for cost savings. Apart from clinical advantages, the use of ICD with atrial sensing capabilities may reduce the incidence of stroke and, in high-risk patients, may also contribute to reduce overall health care costs.

Aims Right ventricular (RV) septum is a non-apical site targeted during lead implantation. Electrocardiographic (ECG) recognition of mid-septal lead location is challenging. The aim of the study is to determine ECG correlates of RV mid-septal pacing. Methods and results The present study is a pre-specified analysis of a prospective, multicenter study, which randomized recipients of an implantable cardioverter defibrillator to an apical vs. mid-septal RV lead positioning. Following implantation, a 12-lead ECG was recorded during intrinsic rhythm and RV pacing. In total, 227 patients, 121 in the apical group (76.9% males, 67.1 ± 11.3 years) and 106 in the mid-septal group (82.1% males, age 64.7 ± 12.7 years) were included. Apically as compared with septally paced patients had significantly longer paced QRS duration (177.0 ± 25.0 vs. 170.4 ± 21.7, respectively, P = 0.03) and significantly more leftward paced QRS axis (−71.6 ± 33.3° vs. 9.4 ± 86.5°, respectively, P < 0.001). A significantly higher proportion of patients in the mid-septal as compared with the apical group displayed predominantly positive QRS in lead V6 (62.3 vs. 4.1%, P < 0.001), predominantly positive QRS in any of the inferior leads (53.8 vs. 4.1%, P < 0.001), and a QR pattern in lead aVL (53.3 vs. 3.3%, P < 0.001). These ECG correlates were incorporated in a stepwise algorithm with total sensitivity of 87% and specificity of 90% for the identification of a mid-septal lead location. Conclusion A mid-septal lead location may be identified using a simple stepwise algorithm, based on the presence of positive QRS in lead V6, positive QRS in any of the inferior leads, and a QR pattern in lead aVL.

Aims The modified anterior line (MAL) is an alternative to the mitral isthmus (MI) line for the treatment of perimitral atrial flutter (PMFL). We sought to investigate acute and long-term efficacy of this line if routinely used for PMFL. Methods and results The cohort included 77 consecutive patients who underwent catheter ablation of PMFL. The anterior line was deployed between the anterolateral mitral annulus and the ostium of the left superior pulmonary vein. Perimitral atrial flutter was either the presenting arrhythmia after persistent atrial fibrillation (AF) ablation (Group 1, n = 42, 54.5%), occurring during AF ablation (Group 2, n = 25, 35%) or presenting as primary arrhythmia (Group 3, n = 8, 10%). Acute success was defined as PMFL termination during MAL deployment with demonstration of bidirectional line block. Acute success was achieved in 68 of 77 patients (88%) without difference between the three groups. In five patients an additional MI line was necessary to terminate PMFL and in four patients both lines failed to achieve termination. During follow-up (16 ± 7 months), 38 of 77 (49%) patients underwent a repeat procedure for a recurrent arrhythmia. During reablation, 13 of 38 (34%) patients were identified to have a PMFL recurrence. Persistent MAL block was demonstrated in 22 of 38 (58%) patients during the repeat ablation. Conclusion The MAL is effective for acute and long-term treatment of PMFL. Maintenance of bidirectional MAL block was shown in 58% of patients during a repeat ablation.

The original version of this article unfortunately contained a mistake.

Electrocardiographic (ECG) identification of prior myocardial infarction (MI) during right ventricular (RV) pacing is of clinical importance. Proposed ECG criteria have been evaluated only during apical pacing. We evaluated the effect of pacing site on the predictive performance of ECG signs of prior MI.The present study is a secondary analysis of a prospective, multicenter study which randomized recipients of an implantable cardioverter defibrillator to an apical versus septal RV lead positioning. ECGs of patients with or without prior MI were analyzed for the presence of the following criteria: Cabrera sign, Chapman sign, QR pattern in leads I, aVL, V5 or V6, QR in inferior leads and notching in the descending slope of the QRS complex in inferior leads.The MI group included 89 patients (55.1% apically paced), while 99 patients had no prior MI (50.5% apically paced). In the total population, the Cabrera sign presented the highest specificity (97%) and diagnostic accuracy (62.2%), with a sensitivity of 23.6%. The Cabrera sign was the only significant predictor of a prior MI [OR=9.9, (95%CI:2.8-34.5), p0.001], among all ECG markers. Pacing site did not significantly influence the sensitivity and specificity of the Cabrera sign for detection of prior MI.In our study, the Cabrera sign was the only ECG marker that predicted the presence of prior MI during ventricular paced rhythm. Septal RV lead positioning did not affect the predictive performance of the Cabrera sign.

Objectives The OPTION (Optimal Anti-Tachycardia Therapy in Implantable Cardioverter-Defibrillator Patients Without Pacing Indications) trial sought to compare long-term rates of inappropriate shocks, mortality, and morbidity between dual-chamber and single-chamber settings in implantable cardioverter-defibrillators (ICDs) patients. Background The use of dual-chamber ICDs potentially allows better discrimination of supraventricular arrhythmias and thereby reduces inappropriate shocks. However, it may lead to detrimental ventricular pacing. Methods This prospective multicenter, single-blinded trial enrolled 462 patients with de novo primary or secondary prevention indications for ICD placement and with left ventricular ejection fractions ≤40% despite optimal tolerated pharmacotherapy. All patients received atrial leads and dual-chamber defibrillators that were randomized to be programmed either with dual-chamber or single-chamber settings. In the dual-chamber setting arm, the PARAD+ algorithm, which differentiates supraventricular from ventricular arrhythmias, and SafeR mode, to minimize ventricular pacing, were activated. In the single-chamber setting arm, the acceleration, stability, and long cycle search discrimination criteria were activated, and pacing was set to VVI 40 beats/min. Ventricular tachycardia detection was required at rates between 170 and 200 beats/min, and ventricular fibrillation detection was activated above 200 beats/min. Results During a follow-up period of 27 months, the time to the first inappropriate shock was significantly longer in the dual-chamber setting arm (p = 0.012, log-rank test), and 4.3% of patients in the dual-chamber setting group compared with 10.3% in the single-chamber setting group experienced inappropriate shocks (p = 0.015). Rates of all-cause death or cardiovascular hospitalization were 20% for the dual-chamber setting group and 22.4% for the single-chamber setting group and satisfied the pre-defined margin for equivalence (p Conclusions Therapy with dual-chamber settings for ICD discrimination combined with algorithms for minimizing ventricular pacing was associated with reduced risk for inappropriate shock compared with single-chamber settings, without increases in mortality and morbidity. (Optimal Anti-Tachycardia Therapy in Implantable Cardioverter-Defibrillator [ICD] Patients Without Pacing Indications [OPTION]; NCT00729703 )

The role of dissociated pulmonary vein (DPV) activity after pulmonary vein isolation (PVI) is still poorly defined. We evaluated electrophysiological features and clinical impact on long-term outcome of DPV activity.A total of 243 patients (mean age 63 ± 11 years; 63% males) undergoing PVI for paroxysmal atrial fibrillation (AF) were included. DPV activity was defined as a residual low frequency irregular PV rhythm. Patients were divided into Group 1 (presence of DPV activity; n = 65) or Group 2 (absence of DPV activity; n = 178).Of 936 isolated PVs, 112 PVs (12%) showed DPV activity. DPV activity was observed more frequently in PVs identified as AF triggers (P = 0.026). During follow-up (mean 12 ± 7 months), 15 of 65 patients of Group 1 (23%) and 57 of 178 patients of Group 2 (32%) had an arrhythmia recurrence (P = 0.23). At linear regression analysis, no independent predictor for clinical recurrence was identified. During the repeat ablation, 62 of 72 patients (86%) showed a recovered PV conduction without difference between the 2 groups. Clinically, all patients of Group 1 with PV reconnection (n = 13/15) had a recurrence of paroxysmal AF. In Group 2, 5 of 52 patients with reconnected PV developed non-PV related arrhythmias.DPV activity occurred in 12% of PVs after PVI and was observed more frequently in PVs identified as AF triggers. DPV activity was not predictive for AF recurrence during follow-up. PV-left atrium reconnection involving PVs with DPV activity leads to AF.

Background— This study aimed to evaluate the safety of continuous periprocedural rivaroxaban administration during left atrial radiofrequency ablation (RFA) in comparison with uninterrupted oral vitamin K antagonist administration. Data about the use of rivaroxaban in the setting of left atrial RFA procedures are lacking. Methods and Results— The study cohort included 544 patients (mean age, 63±10 years) who underwent left atrial RFA procedures between February 2012 and May 2013. All patients (n=272) receiving uninterrupted periprocedural rivaroxaban 15 or 20 mg/d before the procedure (rivaroxaban) were matched by age, sex, and type of rhythm disorder with an equal number of patients managed with uninterrupted vitamin K antagonist phenprocoumon (international normalized ratio, 2–3). During RFA, heparin was given intravenously to maintain an activated clotting time at 270 to 300 s. The safety end point was a composite of bleeding, thromboembolic events, and death. There were no thromboembolic complications and no deaths in either group. The prevalence of major bleeding complications was similar in both groups (1 tamponade in RivG and 1 groin hematoma requiring transfusion in phenprocoumon). Minor bleeding complications occurred equally in both groups (20 of 272; 7% in the rivaroxaban versus 33 of 272, 12% in the phenprocoumon; P =0.08). In multivariable analyses, female sex was associated with a greater risk of complications (odds ratio, 1.96; 95% confidence interval, 1.10–3.49). Conclusions— In patients undergoing left atrial RFA, continuous periprocedural rivaroxaban use seems to be as safe as uninterrupted periprocedural phenprocoumon administration.

Background Detrimental effects of right ventricular (RV) apical pacing have directed the interest toward alternative pacing sites such as the RV mid-septum. As safety data are scarce for implantable cardioverter defibrillator (ICD) recipients the study aims to evaluate ICD lead performance in the mid-septal position. Methods and results A total of 299 ICD recipients (79% male, aged 65.2±12.1years, 83% primary prevention of sudden cardiac death) were randomized to receive the RV ICD electrode either in a mid-septal (n=145) or apical (n=154) location. Event-free survival was evaluated at 3 (primary endpoint) and 12months (secondary endpoint). Events included a composite of lead revision, suboptimal right ventricular electrode performance (including defibrillation thresholds (DFT)>25J) or lead position not in accordance with randomized location. Event-free survival at 3 (12) months was observed in 80.6% (72.3%) of patients randomized to a mid-septal and in 82.2% (72.1%) of patients randomized to an apical lead position, p=0.726 (p=0.969). Pre-defined margins for non-inferiority were not reached at 3 or 12months. High DFT was found in 7 patients (5.0%) of the mid-septal and in 3 (2.2%) patients of the apical group (p=0.209). Conclusion In ICD recipients electrode positioning to the RV mid-septum or the RV apex results in slightly different rates concerning the survival free of lead revision, suboptimal right ventricular electrode performance or non-randomized lead position. Non-inferiority of the mid-septal lead location cannot be concluded. This should be taken into consideration when a mid-septal lead position is pursued. Clinical trial registration ClinicalTrials.gov identifier NCT00745745.

There is little consensus on optimal atrioventricular (AV) and ventricular-to-ventricular (VV) intervals in cardiac resynchronization therapy (CRT). The aim of this study was to examine a novel combination of Doppler echocardiography (DE) and three-dimensional echocardiography (3DE) for individualized AV- and VV-interval optimization compared to conventional electrocardiogram (ECG) optimization.In this double-blind, randomized controlled trial, 77 patients (male: 57, age: 68 ± 10 years) with severely reduced ejection fraction (EF), New York Heart Association (NYHA) class III or IV, and wide QRS complex (>120 ms) have been included. Patients were randomized to either AV- and VV-interval optimization using DE and 3DE (group 1, n = 39) or ECG (group 2, n = 38). 3DE was performed in all patients for the evaluation of left ventricular (LV) dimensions, EF and systolic dyssynchrony index (SDI), and NYHA class obtained before CRT and after 3 months. Primary endpoint of the study was clinical response to CRT, defined as a reduction of NYHA class by>=1 score. Secondary endpoints were change of EF, LV volumes, and SDI.There were significantly more responders in group 1 (82%) than in group 2 (58%, P = 0.021). Similarly, group 1 showed a larger increase in EF (7.0 ± 6.0% vs 3.4 ± 5.6%, P = 0.015) and a more pronounced reduction of SDI (-4.5 ± 5.9% vs -1.5 ± 5.6%, P = 0.039) than group 2.Compared with conventional ECG optimization, this novel echocardiographic optimization protocol resulted in a significantly higher response rate, improved LV systolic function, and may be used to select the optimal AV and VV intervals in CRT.

Die Magnetresonanztomografie (MRT) ist die Methode der ersten Wahl fur viele diagnostische Fragestellungen. Deren Einsatz ist bei Tragern von Herzschrittmachern und implantierbaren Defibrillatoren jedoch ublicherweise limitiert, da die elektromagnetischen Felder und Hochfrequenz-Impulse die Funktion der Implantate beeintrachtigen konnen. Neben Funktionsstorungen, die unmittelbar wahrend der MRT-Untersuchung auftreten, sind auch nachhaltige Schaden der Systemkomponenten beschrieben worden. Das Gefahrdungspotential ist fur Patienten mit fehlendem Eigenrhythmus bzw. Schrittmacherabhangigkeit am grosten. Nutzen und Risiko der MRT mussen bei konventionellen Implantaten daher sorgsam abgewogen werden. Neue Gerate mit reduzierten ferromagnetischen Komponenten und modifizierten Schaltkreisen bieten den Patienten die Moglichkeit zur MRT ohne Systemaffektion. Die periprozedurale Umprogrammierung in einen speziellen asynchronen MRT-Modus gewahrleistet einen storungsfreien Betrieb wahrend der Exposition mit dem elektromagnetischen Feld.

Remote magnetic navigation (RMN) is attributed to diminish radiation exposure for both patient and operator performing catheter ablation for different arrhythmia substrates. The purpose of this prospective, randomized study was to compare RMN with manually guided catheter ablation for AV nodal reentrant tachycardia (AVNRT) regarding fluoroscopy time/dosage, acute and long-term efficacy as well as safety. A total of 218 patients with AVNRT undergoing catheter ablation at three centers (male 34%, mean age 50 ± 17 years) were randomized to a manual approach (n = 113) or RMN (n = 105) using the Niobe® magnetic navigation system. The primary study endpoint was total fluoroscopy time/dosage for patient and operator at the end of the procedure. Secondary endpoints included acute success, procedure duration, complications and success rate after 6 months. Fluoroscopy time and dosage for the patient were significantly reduced in the RMN group compared to the manual group (6 ± 6 vs. 11 ± 10 min; p

Aims Data about the acute and long-term outcome of catheter ablation in patients with D-transposition of the great arteries (d-TGA) post-Mustard/Senning operation are scarce. Methods and results This single-centre retrospective analysis includes 26 patients (mean age 28.7 ± 6.7 years, 8 females) after Mustard ( n = 15) or Senning ( n = 11) operation who underwent catheter ablation for intra-atrial re-entrant tachycardia (IART) or atrioventricular nodal re-entrant tachycardia (AVNRT) from January 2004 to May 2011. The electrophysiological studies were performed using a three-dimensional mapping system (CARTO®). Remote magnetic navigation (RMN) was available since 2008. Follow-up on an outpatient basis was conducted 3, 6, and 12 months after ablation and yearly thereafter. In the 26 patients, 34 procedures were performed (one procedure n = 19, two n = 6, and three n = 1). Overall, 34 tachycardia forms (IART n = 30; AVNRT n = 4) were ablated manually ( n = 25) or by RMN ( n = 9). Acute success reached in 29/34 forms (85.3%). Mean fluoroscopy time (FT) was 28.2 ± 20.7 min and mean procedure duration (PD) was 290.9 ± 107.6 min. After a mean follow-up of 34.1 ± 24.5 months, 25/26 (96.2%) patients were free from IART or AVNRT. In the nine RMN ablations (mean follow-up 14.2 ± 5.8 months) acute and long-term success was 100%. Fluoroscopy time and PD were significantly reduced using RMN compared with manual ablation (11.9 ± 6.2 vs. 34.6 ± 20.6 min, 225.7 ± 24.1 vs. 312 ± 118.2 min, P = 0.02). Conclusion Catheter ablation of IART or AVNRT in patients post-Mustard/Senning operation for d-TGA has a high acute success rate. The recurrence rate for IART is about 30%; however, after a second ablation, long-term results are excellent. Remote magnetic navigation seems to improve single-procedure acute and long-term success and significantly reduces FT and PD.

Background Automatic atrioventricular search hysteresis (AVSH) is designed to reduce the cumulative percentage of potentially deleterious right ventricular apical pacing (VP%) in dual-chamber pacemakers. We investigated whether minimizing VP% by AVSH can, in turn, reduce ventricular wall stretching/stress, as assessed by plasma concentrations of the amino-terminal fragment of the pro-B-type natriuretic peptide (NT-proBNP). Methods After dual-chamber pacemaker implantation in 81 patients (age: 69 ± 11 years; males: 55.6%), the fixed atrioventricular delay of 225 ms was programmed and AVSH was turned off for 1 month. The patients were thereafter randomly assigned to standard AVSH for 1 month, followed by an enhanced AVSH for another month, or vice versa. At the 1-, 2-, and 3-month follow-ups, VP% values were retrieved from the pacemaker memory, and venous blood samples were taken for NT-proBNP measurements. Results Both standard and enhanced AVSH reduced the median VP% value from 38.5% (for the fixed atrioventricular delay) to 2.1% (P < 0.001). However, plasma NT-proBNP concentrations for the fixed atrioventricular delay (median, 253 pg/mL), standard AVSH (225 pg/mL), and enhanced AVSH (276 pg/mL) did not differ significantly on the intrapatient basis (paired Wilcoxon tests) between any pair of these modalities. Conclusion Minimizing ventricular pacing by AVSH during 1 month had no influence on plasma NT-proBNP levels (i.e., ventricular wall stretching/stress) compared with a constant, moderately prolonged atrioventricular delay.

In patients with atrial fibrillation, oral anticoagulation with oral thrombin inhibitors (OTIs), in contrast to vitamin K antagonists (VKAs), associates with a modest increase in acute coronary syndromes (ACSs). Whether this observation is causatively linked to OTI treatment and, if so, whether OTI action is the result of a lower antithrombotic efficacy of OTI compared to VKA or reflects a yet undefined prothrombotic activity of OTI remain unclear. We analyzed platelet function in patients receiving OTI or dose-adapted VKA under static and flow conditions. In vivo, we studied arterial thrombosis in OTI-, VKA-, and vehicle-treated mice using carotid ligation and wire injury models. Further, we examined thrombus formation on human atherosclerotic plaque homogenates under arterial shear to address the relevance to human pathology. Under static conditions, aggregation in the presence of ristocetin was increased in OTI-treated blood, whereas platelet reactivity and aggregation to other agonists were only marginally affected. Under flow conditions, firm platelet adhesion and thrombus formation on von Willebrand factor, collagen, and human atherosclerotic plaque were increased in the presence of OTI in comparison to VKA. OTI treatment was associated with increased thrombus formation in injured carotid arteries of mice. Inhibition or ablation of GPIbα-thrombin interactions abolished the effect of OTI on thrombus formation, suggesting a mechanistic role of the platelet receptor GPIbα and its thrombin-binding site. The effect of OTI was also abrogated in the presence of aspirin. In summary, OTI treatment has prothrombotic activity that might contribute to the increase in ACS observed clinically in patients.