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Pulmonary vein isolation (PVI) in persistent atrial fibrillation (AF) has a low success rate. A newer ablation concept targets left atrial (LA) low voltage zones (LVZ) which correlate with fibrosis and predict recurrence after PVI. We aimed to determine the success of combined PVI- and LVZ-guided ablation and to identify the predictors for LVZ and for ablation success. A total of 119 consecutive patients who underwent their first ablation procedure due to persistent AF were included. After acquisition of a high-resolution LA voltage map, PVI- and LVZ-guided ablation were performed. Mean age was 69 ± 8 years, 53% were men, and 8% had longstanding persistent AF. We found LVZ in 55% of patients. Twelve-month freedom from recurrences off drugs was 69%. The only independent predictor for recurrence was the existence of LVZ (OR 4.2, 95% CI 1.54–11.41, p = 0.005). Existence of LVZ was predicted positively by age ≥ 67 years (OR 4.4, 95% CI 1.4–13.7, p = 0.011), LA volume index ≥ 68 ml/m2 (OR 3.9, 95% CI 1.4–10.5, p = 0.008), and GFR ≤ 85 ml/min/1.73 m2 (OR 12.5, 95% CI 2.0–76.6, p = 0.006). BMI ≥ 26 kg/m2 (OR 0.06, 95% CI 0.01–0.30, p = 0.001) was a negative predictor of LVZ. LVZ-guided ablation in combination with PVI results in comparably high success rates. However, the existence of LVZ remains the strongest predictor of ablation success.

ObjectiveAtrial fibrillation or atrial flutter (AF) and heart failure (HF) often go hand in hand and, in combination, lead to an increased risk of death compared with patients with just one of both entities. Sex-specific differences in patients with AF and HF are under-reported. Therefore, the aim of this study was to investigate sex-specific catheter ablation (CA) use and acute in-hospital outcomes in patients with AF and concomitant HF in a retrospective cohort study.MethodsUsing International Statistical Classification of Diseases and Related Health Problems and Operations and Procedures codes, administrative data of 75 hospitals from 2010 to 2018 were analysed to identify cases with AF and HF. Sex differences were compared for baseline characteristics, right and left atrial CA use, procedure-related adverse outcomes and in-hospital mortality.ResultsOf 54 645 analysed cases with AF and HF, 46.2% were women. Women were significantly older (75.4±9.5 vs 68.7±11.1 years, pConclusionsThere are sex differences in patients with AF and HF with respect to demographics, resource utilisation and in-hospital outcomes. This needs to be considered when treating women with AF and HF, especially for a sufficient patient informed decision making in clinical practice.

Pulmonary vein isolation (PVI) in persistent atrial fibrillation (AF) has a low success rate. A newer ablation concept targets left atrial (LA) low voltage zones (LVZ) which correlate with fibrosis and predict recurrence after PVI. We aimed to determine the success of combined PVI- and LVZ-guided ablation and to identify the predictors for LVZ and for ablation success.A total of 119 consecutive patients who underwent their first ablation procedure due to persistent AF were included. After acquisition of a high-resolution LA voltage map, PVI- and LVZ-guided ablation were performed. Mean age was 69 ± 8 years, 53% were men, and 8% had longstanding persistent AF. We found LVZ in 55% of patients. Twelve-month freedom from recurrences off drugs was 69%. The only independent predictor for recurrence was the existence of LVZ (OR 4.2, 95% CI 1.54-11.41, p = 0.005). Existence of LVZ was predicted positively by age ≥ 67 years (OR 4.4, 95% CI 1.4-13.7, p = 0.011), LA volume index ≥ 68 ml/mLVZ-guided ablation in combination with PVI results in comparably high success rates. However, the existence of LVZ remains the strongest predictor of ablation success.

Single-shot devices have been developed to simplify pulmonary vein isolation (PVI). Randomized studies of the second-generation cryoballoon (CB 2nd) demonstrated excellent results. There are limited data comparing results of circular pulmonary vein ablation catheter (PVAC) with conventional RF ablation or CB for PVI. Using a sequential registry cohort and a prospective randomized study, we aimed to compare the acute and long-term results of CB 2nd and PVAC Gold. In the registry, consecutive patients with paroxysmal atrial fibrillation (AF) undergoing their first PVI were included. The preferred method used was PVAC Gold in 2014 and CB 2nd in 2015. Subsequently, a randomized study (PVAC vs. CB 2nd) was performed. Ablation success was measured as freedom of AF or atrial tachycardias (AT) off antiarrhythmic drugs. In the registry cohort, PVAC Gold was used in 60 patients and CB 2nd in 56 patients (age 66 ± 11 years, 52% male, LAD 43 ± 6). In the randomized study, 20 patients were treated with PVAC Gold and 22 with CB 2nd (age 67 ± 9; 43% men, LAD 40 ± 7 mm). During a mean follow up of 13.2 ± 3.6 months, success was 54% in PVAC Gold patients and 81% in CB 2nd cases (p = 0.001). In the randomized study 12 months success was 50% versus 86%, p

Depending on its occurrence in the germline or somatic context, a single point mutation, S707Y, of phospholipase C-γ2 (PLCγ2) gives rise to two distinct human disease states: acquired resistance of chronic lymphocytic leukemia cells (CLL) to inhibitors of Brutons´s tyrosine kinase (Btk) and dominantly inherited autoinflammation and PLCγ2-associated antibody deficiency and immune dysregulation, APLAID, respectively. The functional relationships of the PLCγ2S707Y mutation to other PLCG2 mutations causing (i) Btk inhibitor resistance of CLL cells and (ii) the APLAID-related human disease PLCγ2-associated antibody deficiency and immune dysregulation, PLAID, revealing different clinical characteristics including cold-induced urticaria, respectively, are currently incompletely understood. Here, we show that PLCγ2S707 point mutants displayed much higher activities at 37° C than the CLL Btk inhibitor resistance mutants R665W and L845F and the two PLAID mutants, PLCγ2Δ19 and PLCγ2Δ20-22. Combinations of CLL Btk inhibitor resistance mutations synergized to enhance PLCγ2 activity, with distinct functional consequences for different temporal orders of the individual mutations. Enhanced activity of PLCγ2S707Y was not observed in a cell-free system, suggesting that PLCγ2 activation in intact cells is dependent on regulatory rather than mutant-enzyme-inherent influences. Unlike the two PLAID mutants, PLCγ2S707Y was insensitive to activation by cooling and retained marked hyperresponsiveness to activated Rac upon cooling. In contrast to the PLAID mutants, which are insensitive to activation by endogenously expressed EGF receptors, the S707Y mutation markedly enhanced the stimulatory effect of EGF, explaining some of the pathophysiological discrepancies between immune cells of PLAID and APLAID patients in response to receptor-tyrosine-kinase activation.

Objectives Microembolic signal detection by transcranial Doppler ultrasonography may be considered a surrogate for cerebral events during invasive cardiac procedures. However, the impact of the microembolic signal count during pulmonary vein isolation on the clinical outcome is not well evaluated. We investigated the effect of the microembolic signal count on the occurrence of new silent cerebral embolism measured by diffusion-weighted imaging (DWI)-magnetic resonance imaging (MRI), changes in neuropsychological testing, and the occurrence of clinical events during long-term follow-up after pulmonary vein isolation. Methods Pulmonary vein isolation was performed in 41 patients. The total microembolic signal burden (classified into “solid,” “gaseous,” and “equivocal”) and sustained thromboembolic showers of greater than 30 seconds were recorded. Diffusion-weighted imaging-MRI and neuropsychological testing were performed before and after pulmonary vein isolation to assess for silent cerebral embolism and neuropsychological sequelae. Long-term follow-up was performed by telephone to assess for stroke/transient ischemic attack. Results A total of 68,729 microembolic signals (14,893 solid, 11,909 gaseous, and 41,927 equivocal) with an average of 1676 signals per patient and 42 thromboembolic showers were recorded. No correlation between the microembolic signal/thromboembolic shower count and the occurrence of new DWI lesions or neuropsychological capability was found. After a mean follow-up ± SD of 49 ± 4 months, 1 patient had an overt transient ischemic event, which was not associated with a high microembolic signal count. Conclusions In this multicenter study, we found no impact of the intraprocedural microembolic symbol/thromboembolic shower count on the occurrence of new DWI lesions, neuropsychological capability, or overt neurologic deficits after pulmonary vein isolation. Thus, not only the microembolic signal count but also procedural/individual factors may contribute to commensurable clinical damage, which may challenge this method as a valid biomarker during pulmonary vein isolation.

AimsCatheter ablation (CA) of ventricular arrhythmias is one of the most challenging electrophysiological interventions with an increasing use over the last years. Several benefits must be weighed against the risk of potentially life-threatening complications which necessitates a steady reevaluation of safety endpoints. Therefore, the aims of this study were (i) to investigate overall in-hospital mortality in patients undergoing such procedures and (ii) to identify variables associated with in-hospital mortality in a German-wide hospital network.Methods and resultsBetween January 2010 and September 2018, administrative data provided by 85 Helios hospitals were screened for patients with main or secondary discharge diagnosis of ventricular tachycardia (VT) or premature ventricular contractions (PVCs) in combination with an arrhythmia-related CA using ICD- and OPS codes. In 5052 cases (mean age 60.9 ± 14.3 years, 30.1% female) of 30 different hospitals, in-hospital mortality was 1.27% with a higher mortality in patients ablated for VT (1.99%, n = 2, 955) compared to PVC (0.24%, n = 2, 097, P 24 h after initial admission (n = 861, P 24 h [odds ratio (OR) 2.28, 95% confidence interval (CI) 1.59–3.28, P ConclusionsWe reported in-hospital mortality rates after CA of ventricular arrhythmias in the largest multicentre, administrative dataset in Germany which can be implemented in quality management programs. Aside from comorbidities, a delayed hospital transfer to a CA performing centre is associated with an increased in-hospital mortality. This deserves further studies to determine the optimal management strategy.

Mutations in the gene encoding phospholipase C-γ2 (PLCγ2) have been shown to be associated with resistance to targeted therapy of chronic lymphocytic leukemia (CLL) with the Bruton's tyrosine kinase inhibitor ibrutinib. The fact that two of these mutations, R665W and L845F, imparted upon PLCγ2 an ∼2–3-fold ibrutinib-insensitive increase in the concentration of cytosolic Ca2+ following ligation of the B cell antigen receptor (BCR) led to the assumption that the two mutants exhibit constitutively enhanced intrinsic activity. Here, we show that the two PLCγ2 mutants are strikingly hypersensitive to activation by Rac2 such that even wild-type Rac2 suffices to activate the mutant enzymes upon its introduction into intact cells. Enhanced “basal” activity of PLCγ2 in intact cells is shown using the pharmacologic Rac inhibitor EHT 1864 and the PLCγ2F897Q mutation mediating Rac resistance to be caused by Rac-stimulated rather than by constitutively enhanced PLCγ2 activity. We suggest that R665W and L845F be referred to as allomorphic rather than hypermorphic mutations of PLCG2. Rerouting of the transmembrane signals emanating from BCR and converging on PLCγ2 through Rac in ibrutinib-resistant CLL cells may provide novel drug treatment strategies to overcome ibrutinib resistance mediated by PLCG2 mutations or to prevent its development in ibrutinib-treated CLL patients.

Deletions in the gene encoding signal-transducing inositol phospholipid-specific phospholipase C-γ2 (PLCγ2) are associated with the novel human hereditary disease PLAID (PLCγ2-associated antibody deficiency and immune dysregulation). PLAID is characterized by a rather puzzling concurrence of augmented and diminished functions of the immune system, such as cold urticaria triggered by only minimal decreases in temperature, autoimmunity, and immunodeficiency. Understanding of the functional effects of the genomic alterations at the level of the affected enzyme, PLCγ2, is currently lacking. PLCγ2 is critically involved in coupling various cell surface receptors to regulation of important functions of immune cells such as mast cells, B cells, monocytes/macrophages, and neutrophils. PLCγ2 is unique by carrying three Src (SH) and one split pleckstrin homology domain (spPH) between the two catalytic subdomains (spPHn-SH2n-SH2c-SH3-spPHc). Prevailing evidence suggests that activation of PLCγ2 is primarily due to loss of SH-region-mediated autoinhibition and/or enhanced plasma membrane translocation. Here, we show that the two PLAID PLCγ2 mutants lacking portions of the SH region are strongly (>100-fold), rapidly, and reversibly activated by cooling by only a few degrees. We found that the mechanism(s) underlying PLCγ2 PLAID mutant activation by cool temperatures is distinct from a mere loss of SH-region-mediated autoinhibition and dependent on both the integrity and the pliability of the spPH domain. The results suggest a new mechanism of PLCγ activation with unique thermodynamic features and assign a novel regulatory role to its spPH domain. Involvement of this mechanism in other human disease states associated with cooling such as exertional asthma and certain acute coronary events appears an intriguing possibility.

Background Focal impulse and rotor modulation (FIRM)-guided ablation targets sites that are thought to sustain atrial fibrillation (AF). Objective The purpose of this study was to evaluate the acute and mid-term outcomes of FIRM-guided only ablation in patients with nonparoxysmal AF. Methods We prospectively enrolled patients with persistent and long-standing persistent (LSP) AF at three centers to undergo FIRM-guided only ablation. We evaluated acute procedural success (defined as AF termination, organization, or ≥10% slowing), safety (incidence of periprocedural complications), and long-term success (single-procedure freedom from atrial tachycardia [AT]/AF off antiarrhythmic drugs [AAD] after a 2-month blanking period). Results Twenty-nine patients with persistent (N = 20) and LSP (N = 9) AF underwent FIRM mapping. Rotors were presents in all patients, with a mean of 4 ± 1.2 per patient (62% were left atrial); 1 focal impulse was identified. All sources were successfully ablated, and overall acute success rate was 41% (0 AF termination, 2 AF slowing, 10 AF organization). There were no major procedure-related adverse events. After a mean 5.7 months of follow-up, single-procedure freedom from AT/AF without AADs was 17%. Conclusion In nonparoxysmal AF patients, targeted ablation of FIRM-identified rotors is not effective in obtaining AF termination, organization, or slowing during the procedure. After mid-term follow-up, the strategy of ablating FIRM-identified rotors alone did not prevent recurrence from AT/AF.

Relationship of Rotors and Low Voltage ZonesIntroduction Focal impulses (FI) and rotors are sources associated with the initiation and maintenance of atrial fibrillation (AF). Their ablation results in a lower recurrence rate. The aim of this study was to characterize for the first time the spatial relationship between such sources and atrial low voltage zones (LVZ) representing fibrosis. Methods Twenty-five consecutive patients undergoing their first ablation for persistent AF were included. Voltage mapping of both atria was done during AF. Endocardial mapping of FI and rotors (sources) was performed using a basket catheter and displayed using RhythmViewTM (Topera Inc.) before ablation. Spatial relationship of LVZ and sources was analyzed. Results LVZs covered 13 ± 12% of right atrial (RA) endocardial surface and 33 ± 25% of left atrial (LA) endocardial surface. The median number of sources was 1 [1–3] in RA and 3 [1–4] in LA. Of LA sources, 18 (30%) were definitely not associated with LVZs or pulmonary vein (PV) antra. Of RA sources, 32 (84%) were remote from LVZ. During ablation of such sources substantial cycle length (CL) prolongation or AF conversion occurred in 11/23 patients (48%). Altogether, 8/11 (73%) of these pertinent sources were located remotely from LVZ and PV antra. Conclusions There is a wide discrepancy in distribution of LVZ areas and sites of identified rotors. Site and incidence of FIRM sources appear to be unpredictable with atrial substrate mapping. Further prospective, randomized studies are necessary to elucidate the impact of additional ablation of such sources in patients with persistent or longstanding persistent AF.

Aims: Catheter ablation is an established therapy in patients with symptomatic atrial fibrillation (AF) with increasing popularity. Pericardial effusion requiring intervention (PE) is one of the most threatening adverse outcomes. The aim of this study was to examine rates of PE after catheter ablation in a large 'real-world' data set in a German-wide hospital network. Methods and results: Using ICD and OPS codes, administrative data of 85 Helios hospitals from 2010 to 2017 was used to identify AF catheter ablation cases [Helios atrial fibrillation ablation registry (SAFER)]. PE occurred in 0.9% of 21 141 catheter ablation procedures. Patients with PE were significantly older, to a higher percentage female, had more frequently hypertension, mild liver disease, diabetes with chronic complications, and renal disease. Low hospital volume (

Aims: Atrial fibrillation (AFib) and atrial flutter (AFlut) are common arrhythmias with increased use of invasive procedures. A steady re-evaluation of relevant safety endpoints is recommended and both quality management and pay-for-performance programs are evolving. Therefore, the aims of this study were (i) to investigate and report overall in-hospital mortality and mortality of invasive arrhythmia-related procedures and (ii) to identify mortality predictors in a German-wide hospital network. Methods and results: Administrative data provided by 78 Helios hospitals between 2010 and 2017 were examined using International Statistical Classification of Diseases and Related Health Problems- and Operations and Procedures-codes to identify patients with AFib or AFlut as main discharge diagnosis or secondary diagnosis combined with invasive arrhythmia-related interventions. In 161 502 patients, in-hospital mortality was 0.6% with a significant decrease from 0.75% to 0.5% (P

Effects of Different Energy Settings in nMARQ Ablation Background Single-shot ablation devices for pulmonary vein isolation (PVI) in patients with symptomatic atrial fibrillation (AF) have been increasingly used in clinical practice. Objective A novel mapping-system integrated irrigated multipolar circular ablation catheter (nMARQ) has been introduced for PVI but data on larger patient cohorts on acute safety and efficacy are lacking. Methods A total of 145 consecutive patients undergoing AF ablation treated with the nMARQ underwent endoscopic evaluation of esophageal thermal damage (EDEL) and brain MRI for detection of silent cerebral events (SCE). During the course of our experience different modifications of the ablation strategy, including energy delivery at the left atrial posterior wall, were evaluated. Results Effective PVI was achieved in 99% of all PVs during a mean procedure-duration of 115 (±36) minutes and ablation-duration of 18 (±8) minutes. Acute major complications occurred in 3 patients (2.1%) and asymptomatic complications like SCE in 26% and EDEL in 21%. There was a significant reduction in EDEL when not using a thermal esophageal probe (0% vs. 28%, P < 0.0001). Ablation under oral anticoagulation led to lower SCE incidences compared to interrupted anticoagulation regimen (15% vs. 31%, P = 0.7). Out of 65 patients with completed 12-month follow-up, 43 (66%) were in stable sinus rhythm. Conclusions PVI using the nMARQ is safe and effective in patients with symptomatic AF. Not using an esophageal temperature probe during ablation has relevantly reduced the incidence of EDEL. Ablations under continued oral anticoagulation have reduced incidence of SCE. Further studies on long-term efficacy are needed.

Background Endoscopically detected esophageal lesions (EDELs) have been identified in apparently asymptomatic patients after catheter ablation of atrial fibrillation (AF). The use of esophageal probes to monitor luminal esophageal temperature (LET) during catheter ablation to protect esophageal damage is currently controversial. Objective The purpose of this study was to investigate the impact of the use of esophageal temperature probes during AF catheter ablation on the incidence of EDELs. Methods Eighty consecutive patients (mean age 63.8 ± 11.36 years; 68.8% men) with symptomatic, drug-refractory paroxysmal (n = 52, 65%) or persistent AF who underwent left atrial radiofrequency catheter ablation were prospectively enrolled. Posterior wall ablation was power limited (≤25 W). In the first 40 patients, LET was monitored continuously (group A), whereas no esophageal temperature probe was used in group B (n = 40 patients). Assessment of EDEL was performed by endoscopy within 2 days after radiofrequency catheter ablation. Results Overall, 13 patients (16%) developed EDELs after AF ablation. The incidence of EDELs was significantly higher in group A than group B (30% vs 2.5%, P P = .02). Multivariable logistic regression analysis revealed the use of an esophageal temperature probe as the only independent predictor for the development of EDEL (odds ratio 16.7, P Conclusion The use of esophageal temperature probes in the setting of AF catheter ablation per se appears to be a risk factor for the development of EDEL.

The Rho GTPase Rac is crucially involved in controlling multiple B cell functions, including those regulated by the B cell receptor (BCR) through increased cytosolic Ca2+. The underlying molecular mechanisms and their relevance to the functions of intact B cells have thus far remained unknown. We have previously shown that the activity of phospholipase Cγ2 (PLCγ2), a key constituent of the BCR signalosome, is stimulated by activated Rac through direct protein-protein interaction. Here, we use a Rac-resistant mutant of PLCγ2 to functionally reconstitute cultured PLCγ2-deficient DT40 B cells and to examine the effects of the Rac-PLCγ2 interaction on BCR-mediated changes of intracellular Ca2+ and regulation of Ca2+-regulated and nuclear-factor-of-activated-T-cell-regulated gene transcription at the level of single, intact B cells. The results show that the functional Rac-PLCγ2 interaction causes marked increases in the following: (i) sensitivity of B cells to BCR ligation; (ii) BCR-mediated Ca2+ release from intracellular stores; (iii) Ca2+ entry from the extracellular compartment; and (iv) nuclear translocation of the Ca2+-regulated nuclear factor of activated T cells. Hence, Rac-mediated stimulation of PLCγ2 activity serves to amplify B cell receptor-induced Ca2+ signaling. Background: Phospholipase Cγ2 (PLCγ2) is stimulated by Rac GTPases through direct protein-protein interaction. Results: The Rac-PLCγ2 interaction markedly enhances B cell-receptor-mediated Ca2+ mobilization and nuclear translocation of the Ca2+-regulated transcription factor NFAT in B cells. Conclusion: Rac-mediated stimulation of PLCγ2 activity amplifies B cell receptor-induced Ca2+ signaling. Significance: A specific Rac-resistant PLCγ2 variant is used to determine the physiological cell signaling relevance of a functional Rac-PLCγ2 interaction in an appropriate cellular context.

Brain magnetic resonance imaging (MRI) has identified a high incidence of cerebral ischemia in asymptomatic patients after atrial fibrillation (AF) ablation (silent). Detection of cerebral ischemic events on MRI is based on acute hyperintense lesions on diffusion-weighted imaging. In the literature, the incidence is related to specifications of MRI and depends on the definition applied. In comparative studies, silent cerebral events (SCE, diffusion-weighted MRI [DWI] positive only) appear to be approximately 3 times more common compared to using a definition of silent cerebral lesions (SCL; without fluid attenuated inverse recovery sequence [FLAIR] positivity). Whereas the FLAIR sequence may turn positive within days after the ischemic event, SCE definition is highly sensitive for early phases of ischemic brain damage. SCE/SCL appear to represent cerebral ischemic infarcts and determine the "embolic fingerprint" of a specific ablation technology and strategy used. The optimum time point for detecting SCE is early after AF ablation (24-72 hours), whereas detection of SCL can only be performed within the first 2-7 days (due to delay of FLAIR positivity). Different technology-, procedure-, and patient-related parameters have been identified to play a role in the multifactorial genesis of SCE/SCL. In recent years, evidence has been gathered that there may be differences of SCE/SCL rates depending upon the ablation technology used, but small patient numbers and a large number of potential confounders hamper all studies. As major findings of recent studies, mode of periprocedural and intraprocedural anticoagulation has been identified as a major predictor for incidences of SCE/SCL. Whereas procedural characteristics related to higher SCE/SCL-rates may be modified, unchangeable patient-related factors should be taken into account for future individualized risk assessment. Novel ablation devices introduced into the market should be tested for their potential embolic fingerprint and refinements of ablation procedures to reduce their embolic potential should be prompted. The knowledge of "best practice" in terms of low SCE/SCL rates has prompted changes in work-flow, which have been implemented into ablation procedures using novel ablation devices. So far, no study has linked SCE/SCL to neuropsychological decline and the low number of AF-ablation-associated events needs to be weighted against the multitude of preexisting asymptomatic MRI-detected brain lesions related to the course of AF itself. Future studies are needed to evaluate if more white matter hyperintensities due to AF may be prevented by AF ablation (producing only a small number of SCE/SCL).

Cryoballoon isolation of the pulmonary veins (PVI) is an effective and safe method in the treatment of patients with paroxysmal atrial fibrillation (PAF). The circular mapping catheter Achieve® (Medtronic Inc., Minneapolis, USA) can be introduced into the pulmonary vein (PV) through the inner lumen of the balloon catheter, allowing online mapping of the PV electrograms during ablation. We prospectively compared the accuracy of this catheter in both available sizes to a standard circular mapping catheter (SCMC) in order to determine bidirectional PV block. Patients with symptomatic PAF underwent cryoballoon ablation using either the Achieve® 15-mm catheter (group 1, 15 patients) or the Achieve® 20 mm (group 2, 15 patients). PV potentials were recorded using Achieve® before, during, and after ablation, and exit block was obtained by pacing from inside the PV. Accuracy of PV potential detection was controlled by a SCMC before and after ablation. Rate of PV which could be isolated exclusively using the Achieve® as guidewire was 98 % (59/60) in group 1 and 93 % (57/60) in group 2. Online signal recording during ablation was possible in 40 and 60 % of PV (p = 0.037), respectively. Final Achieve® diagnosis was accurate in 55/60 (92 %) of the PVs and 12/15 (80 %) of patients in group 1 and 60/60 (100 %) of PV and 15/15 (100 %) of patients in group 2. Stand-alone mapping using Achieve® 15 mm resulted in a significant lack of diagnostic accuracy. Achieve® 20 mm provided excellent diagnostic accuracy comparable to a SCMC and should be preferentially used.

Microembolic signal detection by transcranial Doppler ultrasonography may be considered a surrogate for cerebral events during invasive cardiac procedures. However, the impact of the microembolic signal count during pulmonary vein isolation on the clinical outcome is not well evaluated. We investigated the effect of the microembolic signal count on the occurrence of new silent cerebral embolism measured by diffusion-weighted imaging (DWI)-magnetic resonance imaging (MRI), changes in neuropsychological testing, and the occurrence of clinical events during long-term follow-up after pulmonary vein isolation.Pulmonary vein isolation was performed in 41 patients. The total microembolic signal burden (classified into "solid," "gaseous," and "equivocal") and sustained thromboembolic showers of greater than 30 seconds were recorded. Diffusion-weighted imaging-MRI and neuropsychological testing were performed before and after pulmonary vein isolation to assess for silent cerebral embolism and neuropsychological sequelae. Long-term follow-up was performed by telephone to assess for stroke/transient ischemic attack.A total of 68,729 microembolic signals (14,893 solid, 11,909 gaseous, and 41,927 equivocal) with an average of 1676 signals per patient and 42 thromboembolic showers were recorded. No correlation between the microembolic signal/thromboembolic shower count and the occurrence of new DWI lesions or neuropsychological capability was found. After a mean follow-up ± SD of 49 ± 4 months, 1 patient had an overt transient ischemic event, which was not associated with a high microembolic signal count.In this multicenter study, we found no impact of the intraprocedural microembolic symbol/thromboembolic shower count on the occurrence of new DWI lesions, neuropsychological capability, or overt neurologic deficits after pulmonary vein isolation. Thus, not only the microembolic signal count but also procedural/individual factors may contribute to commensurable clinical damage, which may challenge this method as a valid biomarker during pulmonary vein isolation.

Background Silent cerebral events (SCE) have been identified on magnetic resonance imaging (MRI) in asymptomatic patients after atrial fibrillation (AF) ablation. Procedural determinants influencing the risk for SCE still remain unclear. Objective Comparing the risk for SCE depending on exchanges of catheters (ExCath) over a single transseptal sheath. Methods 88 Patients undergoing pulmonary vein isolation (PVI) only ablation using either single-tip or balloon-based technique underwent pre- and post-ablation cerebral MRI. Ablations were either performed with double transseptal access and without exchanging catheters over the transseptal sheaths (group 1: no ExCath) or after a single transseptal access and exchanges of therapeutic and diagnostic catheters (group 2: ExCath). Differences in regard to SCE rates were analyzed. Multivariate analysis was performed to identify factors related to the risk for SCE. Results Included patients underwent PVI using single tip irrigated radiofrequency in 41, endoscopic laser balloon in 27 and cryoballoon in 20 cases. Overall SCE were identified in 23 (26%) patients. In group 1 (no ExCath; N = 46) 6 patients (13%) and in group 2 (N = 42) 17 patients (40%) had documented SCE (p = 0.007). The applied ablation technology did not affect sCe rate. In multivariate analysis age (OR 1.1, p = 0.03) and catheter exchanges over a single transseptal sheath (OR 12.1, p = 0.007) were the only independent predictors of a higher risk for SCE. Conclusions Exchanging catheters over a single transseptal access to perform left atrial ablation is associated with a significantly higher incidence of SCE compared to an ablation technique using different transseptal accesses for therapeutic and diagnostic catheters.

Patienten mit einer strukturellen Herzerkrankung, die einen elektrischen Sturm erleiden, weisen besonders in den ersten 3 Monaten eine stark erhohte rhythmogene und nichtrhythmogene Mortalitat auf. Nach notfallmasiger Terminierung der ventrikularen Arrhythmie mussen, abhangig vom Ergebnis einer Analyse der zugrunde liegenden Art und Ursache der Arrhythmie, verschiedene Therapiepfade eingeschlagen werden, um eine dauerhafte Rhythmusstabilisierung zu erreichen. Eckpfeiler der Therapie sind Triggerausschaltung, Sympathikusblockade (initial mittels β-Blocker und Sedierung), antiarrhythmische Therapie mit Amiodaron und Katheterablation, aber auch eine Behandlung der Herzinsuffizienz bzw. kreislaufunterstutzende Masnahmen. Der dargestellte Algorithmus kann helfen, auch invasive Masnahmen, wie invasive Koronardiagnostik, Katheterablation oder invasive Kreislaufunterstutzung rechtzeitig in die Therapiestrategie zu integrieren. Durch ein strukturiertes Vorgehen bei der Behandlung von Patienten mit elektrischem Sturm kann eine hohe Effektivitat der Akuttherapie erreicht werden. Ob dies auch zu einer Verbesserung des Outcomes fuhrt, muss im Weiteren evaluiert werden.

Functional mitral regurgitation (FMR) is common in patients with advanced heart failure and impaired left ventricular function. The study aim was to examine functional and hemodynamic effects at three months after MitraClip® implantation in high-risk surgical patients with FMR.A group of 93 patients was rejected for surgical treatment by heart-team decisions due to an inacceptable risk for conventional mitral valve surgery. Between October 2011 and May 2015, 89 of these patients (96%) were treated successfully with MitraClip implantation. A subsequent complete follow up was performed over three months in 32 patients with FMR, including pro-brain natriuretic peptide (pro-BNP) measurements, six-minute walk test, echocardiography, and right heart catheterization.The patients (mean age 73 ± 7 years) presented with a mean left ventricular ejection fraction (LVEF) of 32 ± 13%, and mitral regurgitation (MR) grade ≥3 in 30 of 32 cases (93%). All patients suffered from severe FMR and were highly symptomatic (NYHA functional class III or IV). The mean logistic EuroSCORE was 33%. MitraClip implantation resulted in a significant clinical improvement and reverse cardiac remodelling with a decrease in LV end-diastolic and LV endsystolic diameters, while LVEF was unchanged. In addition, a statistically relevant reduction of systolic, diastolic and mean pulmonary artery pressures (PAPsystolic -7.2 mmHg, p = 0.011; PAPdiastolic -4.5 mmHg, p = 0.003; and PAPmean -5.3 mmHg, p = 0.007) were measured, while the cardiac index (+0.3 l/min/m2, p0.001) and cardiac output (+0.5 l/min, p0.001) were increased significantly. The 30-day mortality was 8.6% (n = 8).Among the study population, MitraClip implantation led to clinical improvement, reverse cardiac remodeling, and a sustained hemodynamic benefit during the three-month follow up period.

Introduction “Single shot” ablation devices to treat symptomatic atrial fibrillation have been engineered over the last years. Safety and efficacy also includes subclinical complications only detected with esophageal endoscopy or cerebral MRI in asymptomatic patients. We studied the acute efficacy and safety profile of a novel multipolar irrigated RF ablation catheter (nMARQ™). Methods and Results Forty-three patients underwent pulmonary vein isolation (PVI) using the novel ablation device. Patient baseline and procedural characteristics were documented. Efficacy of PVI was identified using only the nMARQ™ catheter. All patients underwent postablation endoscopic evaluation of the esophagus to document thermal damage and cerebral MRI (diffusion weight imaging, attenuated diffusion coefficient-map) to document incidence and number of silent cerebral lesions (SCL). Effective PVI was achieved in 98% of targeted PVs in a mean procedure time of 133 minutes. A mean of 4.8, 60-second RF applications, per PV was needed for effective PVI. No clinical procedure-associated complications were noted. Esophageal temperature increase >40.5 °C was noted in 22 (51%) patients and 14 of these had thermal esophageal lesions on endoscopic evaluation. A total of 26 SCLs were noted in 14 patients (33%; 1.9/patient; mean diameter of 2.3 mm, 88% of lesions were ≤3 mm). Conclusions PVI using the novel irrigated RF multipolar ablation device (nMARQ™) appears to be acutely effective. No clinical complications were identified. A high incidence of SCL (33%) and thermal esophageal lesions (33%) bears caution and further studies on long-term efficacy and safety are needed.

Die Katheterablation ventrikularer Arrhythmien hat sich in vielen Zentren zu einem Standardverfahren entwickelt. Es lassen sich sowohl hamodynamisch tolerierte als auch nicht tolerierte VTs effektiv abladieren. Insbesondere bei Patienten mit idiopathischen VTs stellt die Katheterablation ein kuratives Vorgehen dar. Bei Patienten mit struktureller kardialer Grundkrankheit fuhrt die Ablation rezidivierender monomorpher VTs zu einer Reduktion von ventrikularen Arrhythmie-Episoden und sollte fruhzeitig durchgefuhrt werden. Auch eine Ablation bei Patienten mit elektrischem Sturm (gehauftes Auftreten ventrikularer Arrhythmien innerhalb von 24 Stunden) kann akut zu einer Rhythmusstabilisierung und langfristig zu einer verbesserten Prognose fuhren. Zunehmend wird die Ablation monomorpher VTs fruhzeitig, z. B. auch nach einer ersten VT-Episode, eingesetzt; ebenso gewinnt die Ablation auch asymptomatischer gehaufter ventrikularer Extrasystolen zur Beeinflussung der Prognose an Bedeutung.

Introduction: Focal impulse and rotor modulation (FIRM)-guided ablation targets localized sources that are thought to sustain AF. In previous reports, it has been shown that FIRM is effective in terminating or organizing AF. We sought to evaluate the acute success of FIRM in patients with persistent and LSP AF undergoing ablation in our centers. Methods: This was a multicenter prospective observational study. FIRM was performed alone or before conventional ablation. Rotors were ablated as confirmed by their absence during remapping and acute success was defined as AF termination, organization or slowing 10%. Results: 57 patients were enrolled (mean age 63 ± 10; 7% LSP). Rotors-only ablation was performed in 56% of patients, and preceded conventional ablation in 44%. There were no major periprocedural adverse events. No focal impulses were found, while rotors were present in all patients (3.9 ± 1.2 per patient; 66% in the LA). In the RA, the majority of rotors were in the lateral wall (53%) and in the septum (30%). In the LA, most of the rotors were in proximity of the pulmonary veins (48%), with the second most common locations being around the mitral annulus or in the septum (17% and 13% respectively). Mean procedural time for FIRM only procedures was 226 ± 52 minutes vs a median of 210 (168-240) minutes for FIRM + conventional ablation procedures (p = NS). Overall acute success was achieved in 35% of patients (3% AF termination, 16% AF organization, 16% AF slowing) with a mean RF time to complete FIRM ablation of 30 ± 15 minutes; no difference in acute success was found when comparing persistent to LSP patients (28% vs 50%; p = NS). Conventional ablation following FIRM did not significantly increase the rate of acute success (1 additional patient converted to sinus rhythm during pulmonary vein isolation). Conclusion: Rotors were present in all patients undergoing ablation for non-paroxysmal AF, most commonly the right atrial lateral wall, septum or around the pulmonary veins. Their ablation was not effective in obtaining AF organization/termination during the procedure.

Aim The aim of our comprehensive single centre analysis was to evaluate the incidence of coronary heart disease (CHD) in extremely obese patients. Methods and results Between 2005 and 2015 we investigated retrospectively 23,359 patients undergoing cardiac catheterisation in our institution. Patients were divided in six weight classes according to World Health Organization (WHO) criteria [1] (WHO, 2000). Cardiovascular risk factors, comorbidities, CCS stadium [2] (Cox and Naylor, 1992) and NYHA functional class [3] (The Criteria Committee of the New York Heart Association, 1994) were retrieved from electronic patient records. Using multivariable analysis the odds ratio for the target variable CHD with presence of >50% angiographic stenosis was ≥1 with regard to age (OR 1.049, 95% CI 1.045–1.052), male sex (OR 2.507, 95% CI 2.329–2.699), cardiovascular risk factors, atherosclerosis (OR 1.651, 95% CI 1.498–1.820), and presence of angina (OR 4.408, 95% CI 3.892–4.993). NYHA functional class I–IV, absence of angina (OR 0.818, 95% CI 0.729–0.918), and BMI ≥ 40 (OR 0.592, 95% CI 0.494–0.709) resulted in an odds ratio of ≤1. Underweight patients had a higher (5.3%) and overweight (1.2%) and obese patients (class I 0.9% and II 1.1%) a slightly lower all-cause in-hospital mortality compared to extremely obese patients (1.6%). Conclusion Severely obese patients treated in our hospital surprisingly showed a decreased incidence of CHD (46.1% in normal weight and 38.6% in extremely obese patients) while comorbidities increased CHD as expected. Although CHD burden was lower, obesity and associated comorbidities resulted in higher all-cause—in-hospital mortality.

Kammertachykardien kommen haufig bei Patienten mit struktureller Herzerkrankung vor. Es gibt jedoch auch Kammertachykardien bei Patienten ohne nachweisbare Herzerkrankung. Letztere entspringen haufig dem ventrikularen Ausflusstrakt oder dem spezifischen Erregungsleitungssystem. In dem vorliegenden Beitrag werden Pathophysiologie, Diagnostik und der Stellenwert der Katheterablation in der Therapie dieser Tachykardien vorgestellt.

Regelmasige Tachykardien mit breitem Kammerkomplex konnen im klinischen Alltag eine diagnostische Herausforderung sein. Differenzialdiagnostisch muss an folgende Arrhythmiegruppen gedacht werden: 1. Kammertachykardien (VT); 2. supraventrikulare Tachykardien (SVT) mit Schenkelblock; 3. supraventrikulare Tachykardien (SVT) mit antegrad akzessorischer Leitung und 4. eine ventrikulare Stimulation. Aufgrund der Konsequenzen fur die Akut- und Dauertherapie ist eine schnelle und zuverlassige Differenzierung anhand des EKG wichtig. Es existieren zahlreiche EKG-Kriterien die eine mehr oder weniger zuverlassige Unterscheidung v. a. von VT und SVT mit Schenkelblock ermoglichen. Die SVT mit akzessorischer Leitung ist sehr selten. Die ventrikulare Stimulation kann durch Stimulationsartefakte abgegrenzt werden. Im Einzelnen finden v. a. folgende Parameter Anwendung: 1. QRS-Breite >140 ms bei RSB oder >160 ms bei LSB; 2. Fusionsschlage; 3. uberdrehter Rechtslagetyp bei RSB-Morphologie (Nordwestachse); 4. VA-Dissoziation; 5. fehlender RS-Komplex bzw. RS-Intervall >100 ms in V1–V6; 6. positive oder negative Konkordanz in V1–V6; 7. Fehlende initiale r-Zacke oder fehlende S-Zacke in V1 bei Tachykardie mit RSB-Morphologie; 8. Fehlende R-Zacke oder R 60 ms) oder plumpe R-Zacke (R >30 ms) in V1 bei Tachykardie mit LSB-Morphologie; 10. Nachweis einer pathologischen Q-Zacke (besonders in V6 bei Tachykardie mit LSB-Morphologie). Der positive Nachweis eines der genannten Parameter spricht jeweils fur eine VT. Allerdings variiert die Sensitivitat und Spezifitat der einzelnen Parameter stark. Aus diesem Grund wurden mehrere Diagnosealgorithmen vorgeschlagen, die im Wesentlichen auf der konsekutiven Anwendung der oben genannten Kriterien beruhen. Hierdurch lasst sich die Spezifitat und Sensitivitat fur die korrekte Diagnose einer VT oder einer SVT mit Schenkelblock auf jeweils uber 95% erhohen.

Focal impulses (FI) and rotors are sources associated with the initiation and maintenance of atrial fibrillation (AF). Their ablation results in a lower recurrence rate. The aim of this study was to characterize for the first time the spatial relationship between such sources and atrial low voltage zones (LVZ) representing fibrosis.Twenty-five consecutive patients undergoing their first ablation for persistent AF were included. Voltage mapping of both atria was done during AF. Endocardial mapping of FI and rotors (sources) was performed using a basket catheter and displayed using RhythmView(TM) (Topera Inc.) before ablation. Spatial relationship of LVZ and sources was analyzed.LVZs covered 13 ± 12% of right atrial (RA) endocardial surface and 33 ± 25% of left atrial (LA) endocardial surface. The median number of sources was 1 [1-3] in RA and 3 [1-4] in LA. Of LA sources, 18 (30%) were definitely not associated with LVZs or pulmonary vein (PV) antra. Of RA sources, 32 (84%) were remote from LVZ. During ablation of such sources substantial cycle length (CL) prolongation or AF conversion occurred in 11/23 patients (48%). Altogether, 8/11 (73%) of these pertinent sources were located remotely from LVZ and PV antra.There is a wide discrepancy in distribution of LVZ areas and sites of identified rotors. Site and incidence of FIRM sources appear to be unpredictable with atrial substrate mapping. Further prospective, randomized studies are necessary to elucidate the impact of additional ablation of such sources in patients with persistent or longstanding persistent AF.

Single-shot ablation devices for pulmonary vein isolation (PVI) in patients with symptomatic atrial fibrillation (AF) have been increasingly used in clinical practice.A novel mapping-system integrated irrigated multipolar circular ablation catheter (nMARQ) has been introduced for PVI but data on larger patient cohorts on acute safety and efficacy are lacking.A total of 145 consecutive patients undergoing AF ablation treated with the nMARQ underwent endoscopic evaluation of esophageal thermal damage (EDEL) and brain MRI for detection of silent cerebral events (SCE). During the course of our experience different modifications of the ablation strategy, including energy delivery at the left atrial posterior wall, were evaluated.Effective PVI was achieved in 99% of all PVs during a mean procedure-duration of 115 (±36) minutes and ablation-duration of 18 (±8) minutes. Acute major complications occurred in 3 patients (2.1%) and asymptomatic complications like SCE in 26% and EDEL in 21%. There was a significant reduction in EDEL when not using a thermal esophageal probe (0% vs. 28%, P0.0001). Ablation under oral anticoagulation led to lower SCE incidences compared to interrupted anticoagulation regimen (15% vs. 31%, P = 0.7). Out of 65 patients with completed 12-month follow-up, 43 (66%) were in stable sinus rhythm.PVI using the nMARQ is safe and effective in patients with symptomatic AF. Not using an esophageal temperature probe during ablation has relevantly reduced the incidence of EDEL. Ablations under continued oral anticoagulation have reduced incidence of SCE. Further studies on long-term efficacy are needed.

Silent cerebral events (SCE) have been identified on cerebral diffusion-weighted cerebral magnetic resonance imaging (DE-MRI) after catheter ablation (CA) of atrial fibrillation (AF). The purpose of this study was to investigate the impact of atrial remodeling on the incidence of SCE after AF CA. Forty patients (67.8 ± 10 years, 47.5 % women) with symptomatic paroxysmal (n = 11, 27.5 %) or persistent AF undergoing AF CA were prospectively enrolled. LA fibrosis was estimated by intraprocedural bipolar voltage mapping in sinus rhythm. Apoptosis-stimulating fragment (Fas-Ligand) and amino terminal peptide from collagen III (PIIINP) concentrations were analyzed of LA and femoral vein blood. Cerebral DE-MRI was performed 1 to 2 days after CA of AF for detection of SCE. In nine patients (22.5 %), new SCE were detected on DE-MRI after AF CA. Patients with SCE had higher CHA2DS2-VASc score, larger left atrial diameter (LADmax), and higher surface area of left atrial low-voltage (24 ± 11.2 vs 3.5 ± 4.2 %, p

Recently, diffusion-weighted magnetic resonance imaging (DW-MRI) revealed silent cerebral events (SCEs) as an acute complication of pulmonary vein isolation (PVI). We investigated whether SCEs following PVI are associated with neuropsychological deficits observed during patients’ follow-up examinations. After PVI, 52 patients were eligible for follow-up. PVI was performed using a variety of ablation technologies (duty-cycled phased radiofrequency (RF) multipolar ablation with the Pulmonary Vein Ablation Catheter® (PVAC) in 24 patients, cooled-tip RF ablation in 23 patients, and cryoballoon ablation in five patients). Fluid-attenuated inversion recovery (FLAIR)- and DW-MRI studies were performed 1 day before PVI and 1 day and 1 month afterward to detect pre-existing cerebral lesions or post-ablation SCEs. At the same times, eight neuropsychological tests were administered. We evaluated changes in patients’ neuropsychological capabilities and compared changes in patients with SCEs to those without SCEs. FLAIR-MRI revealed pre-existing cerebral lesions in 42 patients (81 %), and DW-MRI demonstrated new SCEs in 25 patients (48 %) (17 treated with phased RF (PVAC) (71 %), six treated with irrigated RF (26 %), and two treated with cryoablation (40 %)). Neuropsychological test results showed no significant impairment (in median z scores) 1 day and 1 month after the ablation procedure. There was no difference in neuropsychological capabilities between patients with SCEs and those without SCEs except in one subtest (part of the verbal working memory test). The incidence of pre-existing cerebral lesions and post-ablation SCEs was high. The frequency of SCEs depends on the ablation technology used. Neither PVI nor post-ablation SCEs have any effect on neuropsychological capabilities.

Brain magnetic resonance imaging (MRI) has identified a high incidence of cerebral ischemia in asymptomatic patients after atrial fibrillation (AF) ablation (silent). Detection of cerebral ischemic events on MRI is based on acute hyperintense lesions on diffusion-weighted imaging. In the literature, the incidence is related to specifications of MRI and depends on the definition applied. In comparative studies, silent cerebral events (SCE, diffusion-weighted MRI [DWI] positive only) appear to be approximately 3 times more common compared to using a definition of silent cerebral lesions (SCL; without fluid attenuated inverse recovery sequence [FLAIR] positivity). Whereas the FLAIR sequence may turn positive within days after the ischemic event, SCE definition is highly sensitive for early phases of ischemic brain damage. SCE/SCL appear to represent cerebral ischemic infarcts and determine the "embolic fingerprint" of a specific ablation technology and strategy used. The optimum time point for detecting SCE is early after AF ablation (24-72 hours), whereas detection of SCL can only be performed within the first 2-7 days (due to delay of FLAIR positivity). Different technology-, procedure-, and patient-related parameters have been identified to play a role in the multifactorial genesis of SCE/SCL. In recent years, evidence has been gathered that there may be differences of SCE/SCL rates depending upon the ablation technology used, but small patient numbers and a large number of potential confounders hamper all studies. As major findings of recent studies, mode of periprocedural and intraprocedural anticoagulation has been identified as a major predictor for incidences of SCE/SCL. Whereas procedural characteristics related to higher SCE/SCL-rates may be modified, unchangeable patient-related factors should be taken into account for future individualized risk assessment. Novel ablation devices introduced into the market should be tested for their potential embolic fingerprint and refinements of ablation procedures to reduce their embolic potential should be prompted. The knowledge of "best practice" in terms of low SCE/SCL rates has prompted changes in work-flow, which have been implemented into ablation procedures using novel ablation devices. So far, no study has linked SCE/SCL to neuropsychological decline and the low number of AF-ablation-associated events needs to be weighted against the multitude of preexisting asymptomatic MRI-detected brain lesions related to the course of AF itself. Future studies are needed to evaluate if more white matter hyperintensities due to AF may be prevented by AF ablation (producing only a small number of SCE/SCL).

Introduction: Silent cerebral events (SCE) have been identified on magnetic resonance imaging (MRI) in asymptomatic patients after atrial fibrillation (AF) ablation. Silent cerebral lesions represent irreversible cerebral damage, comparative analysis using a consistent MRI definition is missing and factors influencing the risk of SCE are poorly understood. Methods: 351 Patients undergoing AF ablation underwent post-ablation cerebral MRI. SCE were identified based on a sensitive definition using a 1.5Tesla MRI including DWI and ADC-map (but not including FLAIR). AF ablation was performed either using irrigated single-tip radiofrequency (RF) ablation (group 1, N=73), phased RF pulmonary vein isolation (PVI) (group 2, N=129), endoscopically-guided laser balloon (group 3, N=41), cryo-balloon PVI (group4, N=34) and irrigated RF multipolar catheters (nMARQ) (group 5, N=73). Differences in regard to SCE rates were analyzed. Results: In group 1 22%, in group 2 37%, in group 41%, in group 4 21% and in group 5 27% of patients had documented SCE. There was a significantly higher incidence of SCL in patients with compared to without exchanges of catheters over a single transseptal sheath (34% vs. 18%, p=0.007) and in patients with left atrial dilation (48% vs. 30%, p=0.01). In a subgroup analysis incidence of SCE was lower when patients were ablated under continued oral anticoagulation (11%) compared to novel oral anticoagulants (33%) or without continuous appropriate anticoagulation bridged with low-molecular weight heparin (45%). Documented left atrial low-voltage areas were associated with a higher incidence of SCE (46% versus 24% in the control group). Conclusions: When using a sensitive MRI definition of SCE incidences are relevantly higher compared to using the “old” definition including the FLAIR-sequence. Technology-associated and procedural characteristics associated with a higher risk of SCE have been identified. Modification of procedural steps of the AF ablation procedure may further reduce the risk of SCE.

In patients with structural heart disease, occurrence of an electrical storm (ES) is associated with increased mortality acutely and during medium term follow-up. Depending on the underlying heart disease and baseline type of arrhythmia, different clinical pathways have to be followed to reach sustained freedom from ventricular arrhythmia recurrences. Trigger elimination, sympathetic blockade (initially using betablockers and sedation), antiarrhythmic therapy with amiodarone and catheter ablation, treatment of heart failure and invasive hemodynamic support are cornerstones of the treatment. We present an algorithm which may help to organize an optimized treatment for each ES patient, implementing invasive treatment options like coronary angioplasty, catheter ablation and invasive circulatory support. Further studies are necessary to evaluate medium term outcome of such a structured therapy.

Catheter ablation is an effective treatment for ventricular tachycardia (VT) in structural heart disease to reduce VT recurrence and implantable cardioverter defibrillator shocks.Current guidelines recommend ablation in patients with recurrent or incessant VT. In patients with left ventricular assist device (LVAD), VTs may be well tolerated hemodynamically and catheter ablation has been performed rarely, until now. We present a case of successful VT ablation in a patient with LVAD and electrical storm. Effective ablation after a transseptal LV access was achieved using electroanatomic mapping and a substrate-based approach. On the basis of this case, we discuss the pros and cons of VT ablation in these patients.

Catheter ablation has been shown to be an effective treatment for rhythm stabilization in patients with multiple ventricular arrhythmia episodes called electrical storm (ES). These procedures may be complex and are usually only performed in highly specialized and experienced centers. Still the optimum timing for catheter ablation in ES remains unclear. Early access to perform acute ablation should be considered in patients who are not rhythm stabilized with antiarrhythmic medical treatment. Also patients with hemodynamic compromise (cardiogenic shock) are candidates for an early interventional strategy. In specialized centers it is consensus to perform catheter ablation in these patients as early as eligible especially when considering a high early and late mortality without interventional management. Establishing a structured protocol for treatment and admission to EP centers has helped to further reduce pre-ablation mortality and may optimize treatment of ES. Large scale networking to optimize and structure access to experienced electrophysiology centers is of importance to create a basis for optimizing treatment strategies.

Percutaneous mitral valve repair (MVR) using MitraClip is an effective alternative treatment for patients with severe mitral valve insufficiency and high perioperative risk for surgery. Atrial fibrillation is frequent in patients needing MVR and some of these patients have contraindications for oral anticoagulation. Combining MitraClip implantation and occlusion of the left atrial appendage (LAA) may be of value in these patients with high thromboembolic risk. We report the first case of combined MitraClip procedure and percutaneous LAA closure in a single procedure.

Trigger sources of paroxysmal atrial fibrillation (PAF) are not limited to a pulmonary vein origin and may be achievable by cardiac vascular structures like the coronary sinus (CS), the vena cava superior and in some rare cases by a persistent left superior vena cava (LSVC). Cryoballoon ablation has been shown to be effective in pulmonary vein isolation. We report an unusual case of using this technique in the dilated CS in case of a persistent LSVC. A 64 year old patient presented PAF recurrences after cryo pulmonary vein isolation 4 months before. A maintaining pulmonary vein isolation could be demonstrated by transseptal mapping. Further bi-atrial mapping localized repetitive atrial trigger activity in a dilated CS proceeding to a LSVC. A cryoballoon was deployed in the CS target area and during cryoablation the triggered activity suspended. Ablation side effects were excluded by coronary angiography. During a follow up time of 8 months the patient has remained free of PAF recurrences. The current report underlines the importance of a patient-tailored ablation approach. Cryothermic balloon technology may be more applicable in delicate cardiac structures by developing new anatomically adapted balloon shapes and sizes.

"Single shot" ablation devices to treat symptomatic atrial fibrillation have been engineered over the last years. Safety and efficacy also includes subclinical complications only detected with esophageal endoscopy or cerebral MRI in asymptomatic patients. We studied the acute efficacy and safety profile of a novel multipolar irrigated RF ablation catheter (nMARQ™).Forty-three patients underwent pulmonary vein isolation (PVI) using the novel ablation device. Patient baseline and procedural characteristics were documented. Efficacy of PVI was identified using only the nMARQ™ catheter. All patients underwent postablation endoscopic evaluation of the esophagus to document thermal damage and cerebral MRI (diffusion weight imaging, attenuated diffusion coefficient-map) to document incidence and number of silent cerebral lesions (SCL). Effective PVI was achieved in 98% of targeted PVs in a mean procedure time of 133 minutes. A mean of 4.8, 60-second RF applications, per PV was needed for effective PVI. No clinical procedure-associated complications were noted. Esophageal temperature increase40.5 °C was noted in 22 (51%) patients and 14 of these had thermal esophageal lesions on endoscopic evaluation. A total of 26 SCLs were noted in 14 patients (33%; 1.9/patient; mean diameter of 2.3 mm, 88% of lesions were ≤3 mm).PVI using the novel irrigated RF multipolar ablation device (nMARQ™) appears to be acutely effective. No clinical complications were identified. A high incidence of SCL (33%) and thermal esophageal lesions (33%) bears caution and further studies on long-term efficacy and safety are needed.