Expert opinion on design and endpoints for studies on catheter ablation of atrial fibrillation.

INTRODUCTION: Catheter ablation of atrial fibrillation (AF) is frequently studied in randomized trials, observational and registry studies. The aim of this expert opinion is to provide guidance for clinicians and industry regarding the development of future clinical studies on catheter ablation of AF, implement lessons learned from previous studies, and promote a higher degree of consistency across studies. BACKGROUND: Studies on catheter ablation of AF may benefit from well-described definitions of endpoints and consistent methodology and documentation of outcomes related to efficacy, safety and cost-effectiveness. The availably of new, innovative technologies warrants further consideration about their application and impact on study design and the choice of endpoints. Moreover, recent insights gained from AF ablation studies suggest a reconsideration of some methodological aspects. METHODS: A panel of clinical experts on catheter ablation of AF and designing and conducting clinical studies developed an expert opinion on the design and endpoints for studies on catheter ablation of AF. Discussions within the expert panel with the aim to reach consensus on predefined topics were based on outcomes reported in the literature and experiences from recent clinical trials. RESULTS: A comprehensive set of recommendations is presented. Key elements include the documentation of clinical AF, medication during the study, repeated ablations and their effect on endpoint assessments, postablation blanking and the choice of rhythm-related and other endpoints. CONCLUSION: This expert opinion provides guidance and promotes consistency regarding design of AF catheter ablation studies and identified aspects requiring further research to optimize study design and methodology. CONDENSED ABSTRACT: Recent insights from studies on catheter ablation of atrial fibrillation (AF) and the availability of new innovative technologies warrant reconsideration of methodological aspects related to study design and the choice and assessment of endpoints. This expert opinion, developed by clinical experts on catheter ablation of AF provides a comprehensive set of recommendations related to these methodological aspects. The aim of this expert opinion is to provide guidance for clinicians and industry regarding the development of clinical studies, implement lessons learned from previous studies, and promote a higher degree of consistency across studies.

Pulmonary vein reconnections or substrate in the left atrium: what is the reason for atrial fibrillation recurrences? A dialogue on a pressing clinical situation.

Pulmonary vein isolation (PVI) has long been held as the cornerstone for atrial fibrillation (AF) ablation. There are patients who do not have successful AF ablations though, especially among those with persistent AF. At the same time, the evidence suggests that ablating beyond the pulmonary veins does not improve success rates. Two possibilities for the incomplete success rates from the procedure are discussed: that more attention needs to be paid to PVI, optimizing delivery of durable, transmural lesions; or alternatively, shifting the focus away from just PVI and addressing the left atrial substrate itself. These two approaches are likely complementary though, and high-density mapping may offer us the ability to undertake them more effectively. The conclusion from this dialogue is that AF is a heterogenous disease and key is to recognize this heterogeneity and respond to it, rather than have a standardized, dogmatic approach. Durable PVI is clearly an important determinant of success but concurrently, we would suggest we need to go beyond this where appropriate to maximize success rates. Clearly the challenge is defining which patients this is appropriate for and how best to do this. Consequently, rather than being 'the' cornerstone of AF ablation, it is more appropriate to consider PVI as 'a' cornerstone of the procedure going forwards and high-density mapping may be the key to optimizing both aspect of the procedure and in so doing improve long term success rates.

[Exposure Therapy with the Help of a Wearable Defibrillator Device used in the Treatment of Severe Obsessive-Compulsive Disorder and Congenital LQTS - An Example for Interdisciplinary Treatment]. / Expositionsbehandlung mithilfe einer Defibrillatorweste bei schwerer Zwangsstörung und angeborenem Long-QT-Syndrom.

We report on a case of a young female suffering from both obsessive-compulsive disorder (OCD) and a severe underlying cardiac disease. Due to the somatic comorbidity, treatment according to guidelines with exposure and reaction prevention was not initially conducted, due to potentially fatal risks to the patient. However, through collaboration with a cardiology clinic, we were able to find an innovative solution which allowed for the continuation of the exposure therapy. This case report demonstrates a successful interdisciplinary collaboration and is intended to sensitize the reader to the need for checking for somatic contraindications before conducting exposure therapy.

Influence of Meteorological Parameters on the Prevalence of TEE Detected Left Atrial Appendage Thrombi.

(1) Background: Meteorological factors seem to exert various effects on human health, influencing the occurrence of diseases such as thromboembolic events and strokes. Low atmospheric pressure in summer may be associated with an increased likelihood of ischemic stroke. The aim of this study was to investigate the potential impact of meteorological conditions on left atrial appendage (LAA) thrombus formation. (2) Methods: A total of 131 patients were included, diagnosed with a first instance of thrombus via 3D transesophageal echocardiography (TEE) between February 2009 and February 2019. Months with frequent thrombus diagnoses of at least 10 thrombi per month were categorized as frequent months (F-months), while months with fewer than 10 thrombus diagnoses per month were labelled as non-frequent months (N-months). The analysis focused on differences in meteorological parameters in two-week and four-week periods before the diagnosis. (3) Results: F-months were predominantly observed in spring and summer (April, May, June, and July), as well as in February and November. During F-months, a higher absolute temperature difference, lower relative humidity, longer daily sunshine duration, and greater wind speed maximum were observed in the two- and four-week periods rather than for N-months. In the two-week period, average temperatures, equivalent temperatures, and temperature maxima were also significantly higher during F-months than N-months. (4) Conclusion: Thrombi in the left atrial appendage are more prevalent during periods characterized by high absolute temperature differences, low relative humidity, and long daily sunshine duration.

Influence of Heart Rate and Change in Wavefront Direction through Pacing on Conduction Velocity and Voltage Amplitude in a Porcine Model: A High-Density Mapping Study.

BACKGROUND: Understanding the dynamics of conduction velocity (CV) and voltage amplitude (VA) is crucial in cardiac electrophysiology, particularly for substrate-based catheter ablations targeting slow conduction zones and low voltage areas. This study utilizes ultra-high-density mapping to investigate the impact of heart rate and pacing location on changes in the wavefront direction, CV, and VA of healthy pig hearts. METHODS: We conducted in vivo electrophysiological studies on four healthy juvenile pigs, involving various pacing locations and heart rates. High-resolution electroanatomic mapping was performed during intrinsic normal sinus rhythm (NSR) and electrical pacing. The study encompassed detailed analyses at three levels: entire heart cavities, subregions, and localized 5-mm-diameter circular areas. Linear mixed-effects models were used to analyze the influence of heart rate and pacing location on CV and VA in different regions. RESULTS: An increase in heart rate correlated with an increase in conduction velocity and a decrease in voltage amplitude. Pacing influenced conduction velocity and voltage amplitude. Pacing also influenced conduction velocity and voltage amplitude, with varying effects observed based on the pacing location within different heart cavities. Pacing from the right atrium (RA) decreased CV in all heart cavities. The overall CV and VA changes in the whole heart cavities were not uniformly reflected in all subregions and subregional CV and VA changes were not always reflected in the overall analysis. Overall, there was a notable variability in absolute CV and VA changes attributed to pacing. CONCLUSIONS: Heart rate and pacing location influence CV and VA within healthy juvenile pig hearts. Subregion analysis suggests that specific regions of the heart cavities are more susceptible to pacing. High-resolution mapping aids in detecting regional changes, emphasizing the substantial physiological variations in CV and VA.

Importance of sinus rhythm as endpoint of persistent atrial fibrillation ablation.

BACKGROUND: The endpoint of persistent atrial fibrillation (AF) ablation is still a matter of debate. The purpose of this study was to evaluate if sinus rhythm (SR) as endpoint of persistent AF ablation has a better long-term outcome compared to atrial tachycardia (AT) or AF at the end of the procedure. METHODS AND RESULTS: Between 2008 and 2011, 191 consecutive patients undergoing de novo catheter ablation for symptomatic persistent and long-standing persistent AF using a sequential ablation approach (including pulmonary vein isolation, ablation of complex fractionated electrograms and linear lesions) were included in the study. According to the result at the end of ablation procedure, patients were classified into 3 groups: patients with termination of AF into SR (Group 1, n = 62), patients with AT undergoing cardioversion (CV) (Group 2, n = 47), or patients with AF undergoing CV (Group 3, n = 82). The primary endpoint was freedom from any atrial tachyarrhythmia off antiarrhythmic drugs at 12 months. At 12 months, estimated proportions of patients free from any arrhythmia recurrence were 42% for Group 1, 13% for Group 2, and 25% for Group 3 (P = 0.002). In a Cox regression analysis only termination into SR was associated with a lower risk of arrhythmia recurrence (HR: 0.62; P = 0.04). CONCLUSION: If SR is achieved as endpoint of persistent and long-standing persistent AF ablation using a sequential ablation approach it is associated with the highest long-term single procedure success rate compared to AT or AF at the end of the procedure.

Acute and long-term outcome after catheter ablation of supraventricular tachycardia in patients after the Mustard or Senning operation for D-transposition of the great arteries.

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.

[Isthmus-dependent right atrial flutter : Clinical course after isthmus ablation]. / Rechtsatriales isthmusabhängiges Vorhofflattern : Klinischer Verlauf nach Isthmusablation.

Ablation of the cavotricuspid isthmus (CTI) to create bidirectional isthmus blockade is the most effective way to achieve rhythm control in typical atrial flutter. Compared with drug therapy, ablation reduces cardiovascular mortality, all-cause mortality, stroke risk, and the risk of cardiac decompensation. Concomitant arrhythmia of atrial flutter is atrial fibrillation (AF); therefore the duration of oral anticoagulation should be adapted according to the risk of stroke and bleeding. A combined procedure of CTI ablation and pulmonary vein isolation (PVI) in patients with typical atrial flutter but without evidence of AF should be evaluated individually especially in patients aged > 54 years depending on (cardiac) comorbidities. The comprehensive diagnostic view should keep in mind not only arrhythmias but also possibly underlying coronary artery disease.

Electroanatomical Conduction Characteristics of Pig Myocardial Tissue Derived from High-Density Mapping.

BACKGROUND: Ultra-high-density mapping systems allow more precise measurement of the heart chambers at corresponding conduction velocities (CVs) and voltage amplitudes (VAs). Our aim for this study was to define and compare a basic value set for unipolar CV and VA in all four heart chambers and their separate walls in healthy, juvenile porcine hearts using ultra-high-density mapping. METHODS: We used the Rhythmia Mapping System to create electroanatomical maps of four pig hearts in sinus rhythm. CVs and VAs were calculated for chambers and wall segments with overlapping circular areas (radius of 5 mm). RESULTS: We analysed 21 maps with a resolution of 1.4 points/mm2. CVs were highest in the left atrium (LA), followed by the left ventricle (LV), right ventricle (RV), and right atrium (RA). As for VA, LV was highest, followed by RV, LA, and RA. The left chambers had a higher overall CV and VA than the right. Within the chambers, CV varied more in the right than in the left chambers, and VA varied in the ventricles but not in the atria. There was a slightly positive correlation between CVs and VAs at velocity values of <1.5 m/s. CONCLUSIONS: In healthy porcine hearts, the left chambers showed higher VAs and CVs than the right. CV differs mainly within the right chambers and VA differs only within the ventricles. A slightly positive linear correlation was found between slow CVs and low VAs.

Prospective assessment of short- and long-term quality of life after ablation for atrial fibrillation.

BACKGROUND: This study prospectively assesses different aspects of short- and long-term quality of life (QoL) after catheter ablation for atrial fibrillation (AF). An analysis of 7 validated generic and tailored questionnaires was performed with regard to the relation of QoL to ablation success. METHODS: The study included 133 patients (74% men, age 57±10) who underwent pulmonary vein isolation ± linear or electrogram-guided substrate modification for AF. QoL was quantitatively assessed at baseline, 3 months after ablation and at a median of 4.3 ± 0.5 years after ablation by the AF severity scale (AFSS), AF symptom checklist (AFSC), WHO-5-Well-Being-Index (WHO), Major Depression Inventory (MDI), Sleep and Vegetative disorder (SV), Vital Exhaustion (VE), and Illness intrusiveness (Ii). RESULTS: QoL was improved significantly 3 months after ablation in all patients (regardless of ablation success or AF type) and stayed significantly improved after a median of 4.3±0.5 years (AFSS, AFSC, WHO, MDI, VE, PE (all P < 0.001), and SV (P = 0.007)). Patients who had a successful ablation improved significantly more than patients with an unsuccessful ablation in the AFSS, AFSC, and MDI questionnaire (delta change from baseline to long-term follow-up P = <0.001, P = <0.001, and P = 0.039, respectively). CONCLUSION: Overall, all patients significantly improved their QoL irrespective of the AF type in all questionnaires 3 months and 4 years after ablation. The increase in QoL was significantly greater in patients who underwent a successful ablation than patients with unsuccessful ablation in the AFSS, AFSC, and MDI questionnaire.

Long-term follow-up after cryoablation for adolescent atrioventricular nodal reentrant tachycardia: recurrence is not predictable.

AIMS: Data about the long-term outcome after cryoablation for atrioventricular nodal reentrant tachycardia (AVNRT) in the paediatric population indicate that recurrence rates are higher with cryo than with radiofrequency energy (RF). The purpose of this study was to review our institutional long-term outcome after cryoablation for AVNRT and to seek for predictors of recurrence. METHODS AND RESULTS: Forty-nine patients (28 female, age 14 ± 2.7 years) undergoing slow-pathway modulation or ablation for AVNRT at our institution from 2004 to 2008 were included in the study.  Acute success was obtained in all patients (100%) with a mean procedure time of 164 ± 50 min and a mean fluoroscopy time of 13 ± 8 min. During a follow-up time of 30 ± 1.9 months, AVNRT recurrence occurred in 11/49 patients (22.4%). Age, sex, number of cryomappings or ablations, catheter tip (4 mm vs. 6 mm), or ablation endpoint (slow-pathway ablation vs. modulation) were not predictive for recurrence. In eight patients, reablation using cryo was performed. All these patients remained free of arrhythmia symptoms during a follow-up of 30 ± 8 months following the second procedure. CONCLUSION: Although cryoablation for the treatment for AVNRT in paediatric and adolescent patients is safe and associated with a high acute success rate, AVNRT recurrence occurs in 22% of patients during long-term follow-up without identifiable predictors for recurrence. A second cryoablation procedure leads to a success rate of 100% during long-term follow-up.

Safety of screening procedures with hand-held metal detectors among patients with implanted cardiac rhythm devices: a cross-sectional analysis.

BACKGROUND: Case reports suggest that the hand-held metal detectors used for security screening generate electromagnetic fields that may interfere with pacemaker and implantable cardioverter-defibrillator (ICD) function. OBJECTIVE: To assess changes in function of pacemakers and ICDs after exposure to hand-held metal detectors. DESIGN: Cross-sectional study. SETTING: Two medical centers in Europe. PATIENTS: 388 patients (209 with pacemakers and 179 with ICDs) presenting for routine follow-up of device function between September 2009 and December 2010. MEASUREMENTS: Abnormalities on electrocardiography suggestive of rhythm device malfunction (pacing inhibition, loss of capture, inappropriate mode switch, ventricular oversensing, and spontaneous reprogramming) after 30 seconds of exposure to 2 widely used hand-held metal detectors with a maximal electromagnetic flux density of 6.3 µT. RESULTS: No change in device function, including pacing or sensing abnormalities or device reprogramming, was observed in any patient. LIMITATIONS: The study included a convenience sample of patients, and the number of different device models tested was small. Testing was conducted in 2 clinic settings. CONCLUSION: Hand-held metal detectors did not affect the function of pacemakers or ICDs in this sample. The use of hand-held metal detectors for security screening is probably safe for patients with pacemakers and ICDs, but these findings require confirmation. PRIMARY FUNDING SOURCE: None.

Potential of remote monitoring to prevent sensing and detection failures in implantable cardioverter defibrillators.

BACKGROUND: Sensing malfunction and misinterpretation of intracardiac electrograms (IEGMs) in patients with implantable cardioverter defibrillators (ICDs) may lead to inadequate device activity such as inappropriate shock delivery or unnecessary mode-switching. Remote monitoring has the potential for early detection of sensing malfunction or misclassification and may thus prevent adverse device activity. Therefore, the authors analyzed the amount, nature, and distribution of misclassification in current ICD and cardiac resynchronization therapy defibrillator technology using the device transmissions of the IN-TIME study population. METHODS: All transmitted tachyarrhythmic episodes in the 664 IN-TIME patients, comprising 2214 device-classified atrial fibrillation (DC-AF) episodes lasting ≥ 30 s and 1330 device-classified ventricular tachycardia or fibrillation (DC-VT/VF) episodes, were manually analyzed by two experienced cardiologists. RESULTS: After evaluation of all DC-VT/VF episodes, a total of 300 VT/VF events (23.1%) were false-positive, with supraventricular tachycardia being the most frequent cause (51.7%), followed by atrial fibrillation (21.3%) and T­wave oversensing (21.0%). A total of 15 patients with false-positive DC-VT/VF received inappropriate shocks. According to the inclusion criteria, 616 IEGMs with DC-AF were assessed. A total of 19.7% were false-positive AF episodes and R­wave oversensing was the most common reason (55.9%). CONCLUSIONS: Remote monitoring offers the opportunity of early detection of signal misclassification and thus early prevention of adverse device reaction, such as inappropriate shock delivery or mode-switching with intermittent loss of atrioventricular synchrony, by correcting the underlying causes.

Cryoablation versus radiofrequency energy for the ablation of atrioventricular nodal reentrant tachycardia (the CYRANO Study): results from a large multicenter prospective randomized trial.

BACKGROUND: Cryoablation has emerged as an alternative to radiofrequency catheter ablation (RFCA) for the treatment of atrioventricular (AV) nodal reentrant tachycardia (AVNRT). The purpose of this prospective randomized study was to test whether cryoablation is as effective as RFCA during both short-term and long-term follow-up with a lower risk of permanent AV block. METHODS AND RESULTS: A total of 509 patients underwent slow pathway cryoablation (n=251) or RFCA (n=258). The primary end point was immediate ablation failure, permanent AV block, and AVNRT recurrence during a 6-month follow-up. Secondary end points included procedural parameters, device functionality, and pain perception. Significantly more patients in the cryoablation group than the RFCA group reached the primary end point (12.6% versus 6.3%; P=0.018). Whereas immediate ablation success (96.8% versus 98.4%) and occurrence of permanent AV block (0% versus 0.4%) did not differ, AVNRT recurrence was significantly more frequent in the cryoablation group (9.4% versus 4.4%; P=0.029). In the cryoablation group, procedure duration was longer (138±54 versus 123±48 minutes; P=0.0012) and more device problems occurred (13 versus 2 patients; P=0.033). Pain perception was lower in the cryoablation group (P<0.001). CONCLUSIONS: Cryoablation for AVNRT is as effective as RFCA over the short term but is associated with a higher recurrence rate at the 6-month follow-up. The risk of permanent AV block does not differ significantly between cryoablation and RFCA. The potential benefits of cryoenergy relative to ablation safety and pain perception are counterbalanced by longer procedure times, more device problems, and a high recurrence rate. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00196222.

Complex fractionated atrial electrogram or linear ablation in patients with persistent atrial fibrillation--a prospective randomized study.

BACKGROUND: Catheter ablation of complex fractionated atrial electrograms (CFAE) for persistent atrial fibrillation (AF) is a promising treatment strategy. We tested the hypothesis that CFAE ablation is superior to linear ablation in patients with persistent or long-standing persistent AF. METHODS: In this study, 116 patients with persistent AF were randomly assigned to undergo circumferential PVI plus additional lines (linear ablation group; 59 patients) or CFAE ablation plus ostial pulmonary vein isolation (PVI) (spot ablation group; 57 patients). Primary endpoint was freedom from atrial tachyarrhythmia after a single ablation procedure (clinical and repeat 7-day Holter), 12 months after ablation without antiarrhythmic medication. RESULTS: The primary endpoint was reached in 22 of 59 (37%) patients of the linear ablation group and in 22 of 57 (39%) patients of the spot ablation group (P = 0.9). Freedom from atrial tachyarrhythmias, including reablations, was achieved in 54% of patients (linear ablation group) versus 56% of patients (spot ablation group; P = 0.8). The incidence of recurrent persistent AF was higher after linear ablation than after spot ablation (21/37 vs 11/35 patients; P = 0.03); atrial tachycardia (AT) was seen more often after spot ablation (10/35 vs 4/37 patients; P = 0.03). CONCLUSION: In patients with persistent AF, CFAE ablation plus PVI reaches the same results as circumferential PVI plus lines, in terms of freedom from symptomatic atrial tachyarrhythmias within the first year after a single ablation procedure. Arrhythmia recurrences in patients after spot ablation were caused more often by AT, whereas recurrent persistent AF was more prevalent after the linear ablation approach.

Safety of implantable pacemakers and cardioverter defibrillators in the magnetic field of a novel remote magnetic navigation system.

INTRODUCTION: Electromagnetic interference with pacemaker and implantable cardioverter defibrillator (ICD) systems may cause temporary or permanent system malfunction of implanted devices. The aim of this study was to evaluate potential interference of a novel magnetic navigation system with implantable rhythm devices. METHODS: A total of 121 devices (77 pacemakers, 44 ICDs) were exposed to an activated NIOBE II® Magnetic Navigation System (Stereotaxis, St. Louis, MO, USA) at the maximal magnetic field strength of 0.1 Tesla and evaluated in vitro with respect to changes in parameter settings of the device, changes of the battery status/detection of elective replacement indication, or alterations of data stored in the device. RESULTS: A total of 115 out of 121 (95%) devices were free of changes in parameter settings, battery status, and internally stored data after repeated exposition to the electromagnetic field of the remote magnetic navigation system. Interference with the magnetic navigation field was observed in 6 pacemakers, resulting in reprogramming to a power-on-reset mode with or without detection of the elective replacement indication in 5 devices and abnormal variance of battery status in one device. All pacemakers could be reprogrammed to the initial modes and the battery status proved to be normal some minutes after the pacemakers had been removed from the magnetic field. CONCLUSION: Interference of a remote magnetic navigation system (at maximal field strength) with pacemakers and ICDs not connected to leads with antitachycardic detection and therapies turned off is rare. Occurring functional abnormalities could be reprogrammed in our sample. An in vitro study will give information about interference of devices connected to leads.

The modified anterior line: an alternative linear lesion in perimitral flutter.

INTRODUCTION: Ablation of left atrial flutter (LAF) is often limited by the need for technically demanding linear lesions. We evaluated the safety and efficacy of a new modified anterior line (MAL), connecting the anterior/anterolateral mitral annulus with the left superior pulmonary vein for ablation of perimitral flutter. METHODS AND RESULTS: MAL was performed in 65 patients (15 females, age 63.6 +/- 9.8 years) with perimitral flutter using 3D mapping systems (70.8% Carto, 29.2% NavX). Perimitral flutter was either the presenting arrhythmia (73.8%) or an intermediate organized rhythm during atrial fibrillation ablation. Follow-up included repetitive 7-day Holter with 93.8% of patients off antiarrhythmics. MAL was acutely effective in 63/65 patients (96.9%). Termination to sinus rhythm occurred in 36 of 65 patients (55.4%), and in 27 of 65 patients (41.5%) there was a change to another LAF type. Bidirectional block across the MAL was achieved in 56 of 65 patients (86.1%). After 6 months of follow-up, 20 of 41 patients (48.8%) had a LAF recurrence, with 6 patients undergoing a reablation. In all redo patients the MAL was still complete and LAF mechanism was different to the initially targeted. No major complication occurred during the ablation procedures or in the postablation period. CONCLUSION: The MAL is a safe and effective linear lesion for the treatment of perimitral LAF. Its value compared to more established linear lesions as the mitral isthmus line has to be evaluated in larger studies.

Very late relapse of atrial fibrillation after pulmonary vein isolation: incidence and results of repeat ablation.

BACKGROUND: There are few data about the incidence of very late (>12 months) arrhythmia relapse after pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (AF) and about the success rate of repeat ablation procedures in this population. METHODS: All patients treated with PVI for paroxysmal AF were screened in the institution's electrophysiology database. Follow-up data at 1, 3, 6, and 12 months and yearly thereafter including repetitive (7 days or 1 day) Holter electrocardiograms were assessed as well as the technique and success rate of repeat ablations. RESULTS: Overall, 24 of 356 (6.7%) patients experienced their first AF recurrence more than 12 months after PVI. Of these 24 patients, 14 underwent reablation for paroxysmal (11 patients) or persistent AF (three patients). Repeat ablation included re-PVI in all 14 patients (43 of 48 initially isolated PVs with recovered left atrial-PV conduction). Ablation of complex fractionated atrial electrograms or left/right atrial lines was performed in eight patients, including the three patients with persistent AF. During follow-up of 15.1 ± 9 months after the second ablation, 10 of 14 (71%) reablated patients remained in sinus rhythm. CONCLUSIONS: After PVI for paroxysmal AF, very late arrhythmia recurrence occurs in less than 10% of patients. The success rate of the repeat procedure is high.

[Implantable ECG monitors]. / Implantierbare EKG-Monitore.

Implantable loop recorders are a diagnostic tool for detecting cardiac arrhythmias and are independent of the patient's compliance. Automatic algorithms lead to a preselection of arrhythmic events that are transferred by telemonitoring to the cardiac specialists. This article describes the available loop recorders on the market, the respective implantation techniques, the indication, and reimbursement.

[Clinical differential indication : Wearables vs implantables]. / Klinische Differenzialindikation : Wearables vs. Implantables.

In order to document arrhythmias, indicated due to symptoms or for prognostic purposes, both invasive and noninvasive possibilities for ECG monitoring are available. The choice of the device for monitoring depends mainly on the frequency of arrhythmias. If they occur less than once a month, long-term monitoring becomes necessary which either continuously monitors the rhythm by an implantable device (implantables) or by wearable systems (wearables) which usually register the ECG discontinuously. Because wearables, e.g. smartphones, are basically ubiquitously available, they may be used for ECG monitoring. This paper comments on the use of implantables and wearables for the detection of atrial fibrillation and the documentation of symptomatic arrhythmias in syncope or palpitations.