Longer and better lives for patients with atrial fibrillation: the 9th AFNET/EHRA consensus conference.

AIMS: Recent trial data demonstrate beneficial effects of active rhythm management in patients with atrial fibrillation (AF) and support the concept that a low arrhythmia burden is associated with a low risk of AF-related complications. The aim of this document is to summarize the key outcomes of the 9th AFNET/EHRA Consensus Conference of the Atrial Fibrillation NETwork (AFNET) and the European Heart Rhythm Association (EHRA). METHODS AND RESULTS: Eighty-three international experts met in Münster for 2 days in September 2023. Key findings are as follows: (i) Active rhythm management should be part of the default initial treatment for all suitable patients with AF. (ii) Patients with device-detected AF have a low burden of AF and a low risk of stroke. Anticoagulation prevents some strokes and also increases major but non-lethal bleeding. (iii) More research is needed to improve stroke risk prediction in patients with AF, especially in those with a low AF burden. Biomolecules, genetics, and imaging can support this. (iv) The presence of AF should trigger systematic workup and comprehensive treatment of concomitant cardiovascular conditions. (v) Machine learning algorithms have been used to improve detection or likely development of AF. Cooperation between clinicians and data scientists is needed to leverage the potential of data science applications for patients with AF. CONCLUSIONS: Patients with AF and a low arrhythmia burden have a lower risk of stroke and other cardiovascular events than those with a high arrhythmia burden. Combining active rhythm control, anticoagulation, rate control, and therapy of concomitant cardiovascular conditions can improve the lives of patients with AF.

First clinical experience of high-power ablation of atrial fibrillation with a novel contact force-sensing gold-tip catheter.

BACKGROUND: Contact force (CF)-sensing catheters are commonly used in the field of radiofrequency (RF) ablation to treat atrial fibrillation (AF). Increasing ablation power (e.g., 50 W) has been suggested as a method to reduce procedure times whilst creating safe and lasting lesions. METHODS: We report the first clinical evidence of a 50 W point-by-point RF ablation in 25 consecutive patients with symptomatic AF using a novel CF-sensing catheter with a gold tip (AlCath Force, Biotronik). We collected and analyzed procedural and ablation parameters. The safety and efficacy of the catheter were evaluated. RESULTS: Altogether, 985 RF lesions in 25 patients were created with a mean number of 39.4 ± 16.3 lesions per patient. The total skin-to-skin procedure time was 116.1 ± 35.1 min, and the mean total area dose product was 10.9 ± 5.1 Gy*cm2. The mean RF time per procedure was 13.2 ± 6.6 min. The mean RF time per lesion was 20.2 ± 8.4 s. The mean CF was 15.7 ± 7.6 g. We observed a mean force time integral of 274.7 ± 11.1 gs (range: 53 to 496 gs). Acute procedural success, defined as entrance and exit block in all pulmonary veins, could be obtained in all cases. No procedure- or device-related serious adverse events were observed. No audible steam pops occurred. Optical inspection of the catheter after the procedure showed neither charring nor clotting. CONCLUSIONS: We provide the first evidence for the safety and efficacy of 50 W ablation using the AlCath Force gold-tip catheter. These data must be supported by a larger multi-center study.

Feasibility and safety of high-power ablation of atrial fibrillation with contact force-sensing catheter: The lesion size index-guided ablation.

BACKGROUND: Radiofrequency (RF) ablation is a commonly used method of atrial fibrillation (AF) treatment. High-power short-duration (HPSD) ablation has been suggested as a method to reduce procedure times whilst creating safe and lasting lesions. High-power ablation with contact force (CF)-sensing technology catheters might aid in a further improvement of safety whilst generating lasting transmural lesions. OBJECTIVES: We report our experience using lesion size index (LSI)-guided 50 W ablation with a CF-sensing catheter of AF. MATERIAL AND METHODS: We performed LSI-guided 50 W point-by-point ablation using a CF-sensing catheter (TactiCath). Target LSI at the anterior left atrium (LA) was 5.0 and at the posterior LA it was 4.5. RESULTS: Altogether, 4641 RF lesions were created in 86 consecutive patients. To reach a mean LSI of 4.9 ±0.01, a mean RF ablation time of 14.3 ±0.1 s was applied with a mean CF of 13.4 ±0.1 g. The RF time per lesion at the anterior wall of LA was 15.9 ±0.2 s, while it was 13 ±0.2 s at the posterior wall of LA. We observed force time integral (FTI) values between 36 g and 310 g. Procedure duration was 107 ±4 min with a RF ablation time of 15.4 ±0.6 min. No audible steam pops occurred. No pericardial effusion was observed. After a 1-year follow-up, no adverse events were reported and 83% of patients had no symptomatic arrhythmia recurrence. CONCLUSIONS: We provide evidence for the safety and efficacy of LSI-guided 50 W ablation using the TactiCath CF-sensing ablation catheter. These data support the use of high-power ablation with CF sensing technology to improve both safety and efficacy.

Magnetic field-induced interactions between phones containing magnets and cardiovascular implantable electronic devices: Flip it to be safe?

BACKGROUND: Recent case reports and small studies have reported activation of the magnet-sensitive switches in cardiovascular implantable electronic devices (CIEDs) by the new iPhone 12 series, initiating asynchronous pacing in pacemakers and suspension of antitachycardia therapies in implantable cardioverter-defibrillators (ICDs). OBJECTIVE: The purpose of this prospective single-center observational study was to quantify the risk of magnetic field interactions of the iPhone 12 with CIEDs. METHODS: A representative model of each CIED series from all manufacturers was tested ex vivo. Incidence and minimum distance necessary for magnet mode triggering were analyzed in 164 CIED patients with either the front or the back of the phone facing the device. The magnetic field of the iPhone 12 was analyzed using a 3-axis Hall probe. RESULTS: Ex vivo, magnetic interference occurred in 84.6% with the back compared to 46.2% with the front of the iPhone 12 facing the CIED. In vivo, activation of the magnet-sensitive switch occurred in 30 CIED patients (18.3%; 21 pacemaker, 9 ICD) when the iPhone 12 was placed in close proximity over the CIED pocket and the back of the phone was facing the skin. Multiple binary logistic regression analysis identified implantation depth (95% confidence interval 0.02-0.24) as an independent predictor of magnet-sensitive switch activation. CONCLUSION: Magnetic field interactions occur only in close proximity and with precise alignment of the iPhone 12 and CIEDs. It is important to advise CIED patients to not put the iPhone 12 directly on the skin above the CIED. Further recommendations are not necessary.

Impaired Relaxation and Reduced Lusitropic Reserve in Atrial Myocardium in the Obese Patients.

Background: Obesity can influence the structure and function of the atrium, but most studies focused on the relationship of body mass index (BMI) and overt left atrium (LA) dysfunction as assessed by clinical imaging. We combined the assessment of right atrium (RA) function in vivo and in vitro in obese and non-obese patients scheduled for elective cardiac surgery. Methods: Atrial structure and function were quantified pre-operatively by echocardiography. RA tissue removed for the establishment of extracorporeal support was collected and RA trabeculae function was quantified in vitro at baseline and with adrenergic stimulation (isoproterenol). Fatty acid-binding protein 3 (FABP3) was quantified in RA tissue. Results were stratified according to the BMI of the patients. Results: About 76 patients were included pre-operatively for the echocardiographic analysis. RA trabeculae function at baseline was finally quantified from 46 patients and RA function in 28 patients was also assessed with isoproterenol. There was no significant correlation between BMI and the parameters of atrial function measured by the clinical echocardiography. However, in vitro measurements revealed a significant correlation between BMI and a prolonged relaxation of the atrial myocardium at baseline, which persisted after controlling for the atrial fibrillation and diabetes by the partial correlation analysis. Acceleration of relaxation with isoproterenol was significantly lower in the obese group (BMI ≥ 30 kg/m2). As a result, relaxation with adrenergic stimulation in the obese group remained significantly higher compared to the overweight group (25 kg/m2 ≤ BMI < 30 kg/m2, p = 0.027) and normal group (18.5 kg/m2 ≤ BMI < 25 kg/m2, p = 0.036). There were no differences on impacts of the isoproterenol on (systolic) developed force between groups. The expression of FABP3 in the obese group was significantly higher compared to the normal group (p = 0.049) and the correlation analysis showed the significant correlations between the level of FABP3 in the RA trabeculae function. Conclusion: A higher BMI is associated with the early subclinical changes of RA myocardial function with the slowed relaxation and reduced adrenergic lusitropy.

Wearable cardioverter-defibrillator: friend or foe in suspected myocarditis?

AIM: Wearable cardioverter defibrillator (WCD, LifeVest, and Zoll) therapy has become a useful tool to bridge a temporarily increased risk for sudden cardiac death. However, despite extensive use, there is a lack of evidence whether patients with myocarditis and impaired LVEF may benefit from treatment with a WCD. METHODS AND RESULTS: We conducted a single-centre retrospective observational study analysing patients with a WCD prescribed between September 2015 and April 2020 at our institution. In total, 135 patients were provided with a WCD, amongst these 76 patients (mean age 48.9 ± 13.7 years; 84.2% male) for clinically suspected myocarditis. Based on the results of the endomyocardial biopsy and, where available cardiac magnetic resonance imaging, 39 patients (51.3%) were diagnosed with myocarditis and impaired LVEF and 37 patients (48.7%) with dilated cardiomyopathy (DCM) without evidence of cardiac inflammation. The main immunohistopathological myocarditis subtype was lymphocytic myocarditis in 36 (92.3%) patients, and four patients (10.3%) of this group had an acute myocarditis. Three patients had cardiac sarcoidosis (7.7%). Ventricular tachycardia occurred in seven myocarditis (in total 41 VTs; 85.4% non-sustained) and one DCM patients (in total one non-sustained ventricular tachycardia). Calculated necessary WCD wearing time until ventricular tachycardia occurrence is 86.41 days in myocarditis compared with 6.46 years in DCM patients. CONCLUSIONS: Our data suggest that myocarditis patients may benefit from WCD therapy. However, as our study is not powered for outcome, further randomized studies powered for the outcome morbidity and mortality are necessary.

Cardiac arrhythmias in patients with COVID-19: Lessons from 2300 telemetric monitoring days on the intensive care unit.

BACKGROUND: Patients with COVID-19 seem to be prone to the development of arrhythmias. The objective of this trial was to determine the characteristics, clinical significance and therapeutic consequences of these arrhythmias in COVID-19 patients requiring intensive care unit (ICU) treatment. METHODS AND RESULTS: A total of 113 consecutive patients (mean age 64.1 ± 14.3 years, 30 (26.5%) female) with positive PCR testing for SARS-CoV2 as well as radiographically confirmed pulmonary involvement admitted to the ICU from March to May 2020 were included and observed for a cumulative time of 2321 days. Fifty episodes of sustained atrial tachycardias, five episodes of sustained ventricular arrhythmias and thirty bradycardic events were documented. Sustained new onset atrial arrhythmias were associated with hemodynamic deterioration in 13 cases (35.1%). Patients with new onset atrial arrhythmias were older, showed higher levels of Hs-Troponin and NT-proBNP, and a more severe course of disease. The 5 ventricular arrhythmias (two ventricular tachycardias, two episodes of ventricular fibrillation, and one torsade de pointes tachycardia) were observed in 4 patients. All episodes could be terminated by immediate defibrillation/cardioversion. Five bradycardic events were associated with hemodynamic deterioration. Precipitating factors could be identified in 19 of 30 episodes (63.3%), no patient required cardiac pacing. Baseline characteristics were not significantly different between patients with or without bradycardic events. CONCLUSION: Relevant arrhythmias are common in severely ill ICU patients with COVID-19. They are associated with worse courses of disease and require specific treatment. This makes daily close monitoring of telemetric data mandatory in this patient group.

Interdisciplinary Clinical Target Volume Generation for Cardiac Radioablation: Multicenter Benchmarking for the RAdiosurgery for VENtricular TAchycardia (RAVENTA) Trial.

PURPOSE: Cardiac radioablation is a novel treatment option for therapy-refractory ventricular tachycardia (VT) ineligible for catheter ablation. Three-dimensional clinical target volume (CTV) definition is a key step, and this complex interdisciplinary procedure includes VT-substrate identification based on electroanatomical mapping (EAM) and its transfer to the planning computed tomography (PCT). Benchmarking of this process is necessary for multicenter clinical studies such as the RAVENTA trial. METHODS AND MATERIALS: For benchmarking of the RAVENTA trial, patient data (epicrisis, electrocardiogram, high-resolution EAM, contrast-enhanced cardiac computed tomography, PCT) of 3 cases were sent to 5 university centers for independent CTV generation, subsequent structure analysis, and consensus finding. VT substrates were first defined on multiple EAM screenshots/videos and manually transferred to the PCT. The generated structure characteristics were then independently analyzed (volume, localization, surface distance and conformity). After subsequent discussion, consensus structures were defined. RESULTS: VT substrate on the EAM showed visible variability in extent and localization for cases 1 and 2 and only minor variability for case 3. CTVs ranged from 6.7 to 22.9 cm3, 5.9 to 79.9 cm3, and 9.4 to 34.3 cm3; surface area varied from 1087 to 3285 mm2, 1077 to 9500 mm2, and 1620 to 4179 mm2, with a Hausdorff-distance of 15.7 to 39.5 mm, 23.1 to 43.5 mm, and 15.9 to 43.9 mm for cases 1 to 3, respectively. The absolute 3-dimensional center-of-mass difference was 5.8 to 28.0 mm, 8.4 to 26 mm, and 3.8 to 35.1 mm for cases 1 to 3, respectively. The entire process resulted in CTV structures with a conformity index of 0.2 to 0.83, 0.02 to 0.85, and 0.02 to 0.88 (ideal 1) with the consensus CTV as reference. CONCLUSIONS: Multicenter efficacy endpoint assessment of cardiac radioablation for therapy-refractory VT requires consistent CTV transfer methods from the EAM to the PCT. VT substrate definition and CTVs were comparable with current clinical practice. Remarkable differences regarding the degree of agreement of the CTV definition on the EAM and the PCT were noted, indicating a loss of agreement during the transfer process between EAM and PCT. Cardiac radioablation should be performed under well-defined protocols and in clinical trials with benchmarking and consensus forming.

Low-voltage shock impedance measurements: A false sense of security.

BACKGROUND: Implantable cardioverter defibrillators use low-voltage shock impedance measurements to monitor the lead integrity. However, previous case reports suggest that low-voltage shock impedance measurements may fail to detect insulation breaches that can cause life-threatening electrical short circuits. METHODS AND RESULTS: We report six cases of insulation breaches in transvenous defibrillation leads that were not obvious during standard interrogations and testing of the lead beforehand. In two cases, an electrical short circuit during commanded shock delivery for internal electrical cardioversion resulted in a total damage of the ICD generator. In one of these cases, commanded shock delivery induced ventricular fibrillation, which required external defibrillation. In two cases, a shock due to ventricular tachycardia was aborted as the shock impedance was less than 20 Ω. However, in both cases the tiny residual shock energy terminated the ventricular tachycardia. In contrast, in one case the residual energy of the aborted shock did not end ventricular fibrillation induced at defibrillator threshold testing. In one case, the ICD indicated an error code for a short circuit condition detected during an adequate shock delivery. CONCLUSIONS: This case series illustrates that low-voltage shock impedance measurements can fail to detect insulation breaches. These data suggest that in patients without a contraindication, traditional defibrillator threshold testing or high voltage synchronized shock at the time of device replacement should be considered.

Are Contemporary Smartwatches and Mobile Phones Safe for Patients With Cardiovascular Implantable Electronic Devices?

OBJECTIVES: Given the increasing prevalence of mobile phone and smartwatch use, this study tested patients with cardiovascular implantable electronic devices (CIEDs) for the incidence and consequence of contemporary mobile phone and smartwatch-produced electromagnetic interferences. BACKGROUND: Electromagnetic interferences can be hazardous for patients with CIEDs. METHODS: In total, 148 patients with CIEDs and leads from 4 different manufacturers were subjected to 1,352 tests. Analyzed CIEDs included 51 pacemakers, 5 cardiac resynchronization therapy pacemakers, 46 implantable cardioverter-defibrillators, 43 cardiac resynchronization therapy defibrillators, and 3 implantable loop recorders. To analyze a possible influence of certain distances between the mobile phone (iPhone 6) and the smartwatch (Apple Watch A1553) to the CIED, both were placed either directly above implanted devices or at the right wrist. All possible activations of the iPhone and the Apple Watch, including the standby, dialing, and connecting modes (telephone connection and Internet access) were tested. In addition, we studied incidence and characteristics of interferences with interrogation telemetry. RESULTS: In this study, only a single case of mobile phone-induced electromagnetic interference on a dual-chamber pacemaker was observed. Utilizing wanded telemetry, iPhone induced interferences were found in 14% of the patients. However, none of the patients showed any interference with the Apple Watch. CONCLUSIONS: The risk of electromagnetic interferences of the iPhone 6 and the Apple Watch with CIEDs is low. However, close proximity of the iPhone 6 to implanted devices can cause telemetry interferences.

Novel variants in TECRL cause recessive inherited CPVT type 3 with severe and variable clinical symptoms.

INTRODUCTION: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmia syndrome characterized by adrenergically stimulated ventricular tachycardia. The most common form of CPVT is due to autosomal dominant variants in the cardiac ryanodine-receptor gene (RYR2). However, trans-2,3-enoyl-CoA reductase-like (TECRL) was recently suggested to be a novel candidate gene for life-threatening inherited arrhythmias. Patients previously reported with pathogenic changes in TECRL showed a special mixed phenotype of CPVT and long-QT-syndrome (LQTS) termed CPVT type 3 (CPVT3), an autosomal recessive disorder. METHODS AND RESULTS: We implemented TECRL into our NGS panel diagnostics for CPVT and LQTS in April 2017. By December 2018, 631 index patients with suspected CPVT or LQTS had been referred to our laboratory for genetic testing. Molecular analysis identified four Caucasian families carrying novel variants in TECRL. One patient was homozygous for Gln139* resulting in a premature stop codon and loss-of-function of the TECRL protein. Another patient was homozygous for Pro290His, probably leading to an altered folding of the 3-oxo-5-alpha steroid 4-dehydrogenase domain of the TECRL protein. The LOF-variant Ser309* and the missense-variant Val298Ala have been shown to be compound heterozygous in another individual. NGS-based copy number variation analysis and quantitative PCR revealed a quadruplication of TECRL in the last individual, which is likely to be a homozygous duplication. CONCLUSION: The data from our patient collective indicate that CPVT3 occurs much more frequently than previously expected. Variants in TECRL may be causative in up to 5% of all CPVT cases. According to these findings, the default analysis of this gene is recommended if CPVT is suspected.

The effect of iron deficiency on cardiac resynchronization therapy: results from the RIDE-CRT Study.

AIMS: Cardiac resynchronization therapy (CRT) improves functional status, induces reverse left ventricular remodelling, and reduces hospitalization and mortality in patients with symptomatic heart failure, left ventricular systolic dysfunction, and QRS prolongation. However, the impact of iron deficiency on CRT response remains largely unclear. The purpose of the study was to assess the effect of functional and absolute iron deficiency on reverse cardiac remodelling, clinical response, and outcome after CRT implantation. METHODS AND RESULTS: The relation of iron deficiency and cardiac resynchronization therapy response (RIDE-CRT) study is a prospective observational study. We enrolled 77 consecutive CRT recipients (mean age 71.3 ± 10.2 years) with short-term follow-up of 3.3 ± 1.9 months and long-term follow-up of 13.0 ± 3.2 months. Primary endpoints were reverse cardiac remodelling on echocardiography and clinical CRT response, assessed by change in New York Heart Association classification. Echocardiographic CRT response was defined as relative improvement of left ventricular ejection fraction ≥ 20% or left ventricular global longitudinal strain ≥ 20%. Secondary endpoints were hospitalization for heart failure and all-cause mortality (mean follow-up of 29.0 ± 8.4 months). At multivariate analysis, iron deficiency was identified as independent predictor of echocardiographic (hazard ratio 4.97; 95% confidence interval 1.15-21.51; P = 0.03) and clinical non-response to CRT (hazard ratio 4.79; 95% confidence interval 1.30-17.72, P = 0.02). We found a significant linear-by-linear association between CRT response and type of iron deficiency (P = 0.004 for left ventricular ejection fraction improvement, P = 0.02 for left ventricular global longitudinal strain improvement, and P = 0.003 for New York Heart Association response). Iron deficiency was also significantly associated with an increase in all-cause mortality (P = 0.045) but not with heart failure hospitalization. CONCLUSIONS: Iron deficiency is a negative predictor of effective CRT therapy as assessed by reverse cardiac remodelling and clinical response. Assessment of iron substitution might be a relevant treatment target to increase CRT response and outcome in chronic heart failure patients.

Phasic Left Atrial Function in Cancer Patients Before Initiation of Anti-Cancer Therapy.

: We aimed to explore left atrial (LA) remodeling in the patients with solid cancer before initiation of chemo- or radiotherapy. This retrospective investigation included 92 chemo- and radiotherapy-naive cancer patients and 40 age- and gender-matched controls with a similar cardiovascular risk profile as the cancer group. All participants underwent comprehensive echocardiographic examination before the start of chemo- or radiotherapy. LA phasic function was evaluated in volumetric and strain method. Indexed minimal and pre-A LA volumes were significantly higher in the cancer patients. Total and passive LA emptying fraction (EF) were significantly lower, whereas active LAEF was significantly higher in the cancer patients. LA total longitudinal strain was significantly lower in the cancer patients. Strain rate analysis of LA phasic function showed that LA function during systole and early diastole was reduced in the cancer group, while it was increased during late diastole. These findings indicated that LA reservoir and conduit functions, assessed with LA volumetric and strain analysis, were deteriorated in the cancer group. On the other hand, LA booster pump function was elevated in the cancer group in comparison with the controls. In the whole population, cancer was associated with reduced LA total longitudinal strain independently of age, gender, BMI, LV hypertrophy, E/e' ratio, diabetes, and hypertension. LA phasic function was impaired in the chemo- and radiotherapy-naive cancer patients in comparison with the control group. Cancer, LV hypertrophy, and hypertension were associated with reduced LA longitudinal strain independently of other important clinical parameters.

Ventricular Tachycardia (VT) Storm After Cryoballoon-Based Pulmonary Vein Isolation.

BACKGROUND Following catheter ablation of atrial fibrillation, increased incidence of ventricular arrhythmia has been observed. We report a case of sustained ventricular arrhythmia in a patient who underwent cryoballoon-based pulmonary vein isolation for symptomatic persistent atrial fibrillation. CASE REPORT A 57-year-old patient with dilated cardiomyopathy underwent CB-based pulmonary vein isolation for symptomatic persistent AF. On the day following an uneventful procedure, the patient for the first time experienced a sustained ventricular tachycardia that exacerbated into VT storm. Each arrhythmia was terminated by the ICD that had been implanted for primary prevention. Antiarrhythmic treatment with amiodarone was initiated immediately. The patient remained free from sustained ventricular arrhythmia during follow-up. CONCLUSIONS After pulmonary vein isolation, physicians should be vigilant for ventricular arrhythmia. The influence of atrial autonomic innervation on ventricular electrophysiology is largely unknown.

Cardiac Implantable Electronic Device Interrogation at Forensic Autopsy: An Underestimated Resource?

BACKGROUND: Postmortem interrogations of cardiac implantable electronic devices (CIEDs), recommended at autopsy in suspected cases of sudden cardiac death, are rarely performed, and data on systematic postmortem CIED analysis in the forensic pathology are missing. The aim of the study was to determine whether nonselective postmortem CIED interrogations and data analysis are useful to the forensic pathologist to determine the cause, mechanism, and time of death and to detect potential CIED-related safety issues. METHODS: From February 2012 to April 2017, all autopsy subjects in the department of forensic medicine at the University Hospital Charité who had a CIED underwent device removal and interrogation. Over the study period, 5368 autopsies were performed. One hundred fifty subjects had in total 151 CIEDs, including 109 pacemakers, 35 defibrillators, and 7 implantable loop recorders. RESULTS: In 40 cases (26.7%) time of death and in 51 cases (34.0%) cause of death could not be determined by forensic autopsy. Of these, CIED interrogation facilitated the determination of time of death in 70.0% of the cases and clarified the cause of death in 60.8%. Device concerns were identified in 9 cases (6.0%), including 3 hardware, 4 programming, and 2 algorithm issues. One CIED was submitted to the manufacturer for a detailed technical analysis. CONCLUSIONS: Our data demonstrate the necessity of systematic postmortem CIED interrogation in forensic medicine to determine the cause and timing of death more accurately. In addition, CIED analysis is an important tool to detect potential CIED-related safety issues.

Left atrial strain predicts recurrence of atrial arrhythmias after catheter ablation of persistent atrial fibrillation.

INTRODUCTION: Success rates of catheter ablation (CA) of persistent atrial fibrillation (AF) are very variable. Identifying patients in whom sinus rhythm maintenance cannot be achieved after CA is a critical issue. METHODS: 2D speckle-tracking echocardiography was performed before the first CA procedure in consecutive patients with persistent AF. Left atrial (LA) strain was correlated with recurrence of atrial arrhythmias during the follow-up period of 15 months after one CA procedure with or without antiarrhythmic drugs (primary endpoint). In a secondary analysis, recurrences after two CA procedures were analysed. RESULTS: 102 patients were included. Patients with recurrence of atrial arrhythmias after one CA procedure (n=55) had significantly lower LA strain than those without recurrence (LA strain 9.7±2.4% vs 16.2±3.0%; p<0.001). Recurrence rate was significantly higher in patients with LA strain <10% than in those with LA strain between 10% and 14.5% and >14.5% (97.7%, 42.1% and 10.3%, respectively; p<0.001). In Cox regression analysis including age, comorbidities, left ventricular dysfunction and LA enlargement, low LA strain (<10%) was the strongest factor associated with recurrence of AF (HR 6.4 (2.4-16.9), p<0.001). Even after inclusion of a second CA procedure, LA strain <10% maintained a high predictive value for recurrence of atrial arrhythmias (86.4% (95% CI 73.3% to 93.6%)). CONCLUSION: In patients with persistent AF, LA strain imaging could be very useful to select those patients who have a high risk of not benefiting from CA.

Catheter ablation of atrial flutter: A survey focusing on post ablation oral anticoagulation management and ECG monitoring.

BACKGROUND: A considerable amount of patients with typical atrial flutter develop atrial fibrillation after cavotricuspid isthmus (CTI) ablation. No uniform recommendations are available to guide anticoagulation regimes or electrocardiogram (ECG) monitoring strategies after this procedure. METHODS: We conducted a web-based survey in electrophysiology (EP) centers in Germany, Switzerland, and Austria. Responses were received from 47 centers. The survey was designed to investigate variations in management of the following: ablation strategy, oral anticoagulation (OAC) management, and ECG monitoring after successful CTI ablation. RESULTS: More than 55% of the participating centers assume that at least every third patient will develop atrial fibrillation during follow-up. Despite this assumption, most EP experts (81%) would still stop OAC after CTI ablation even in patients with higher CHADS2-VA2SC-score, or even perform CTI in asymptomatic patients with the purpose to stop OAC (52%). Most experts agree that ECG monitoring is necessary during follow-up. A majority still rely on short-term monitoring tools like resting ECGs (7%) or Holter ECGs (43%), while continuous monitoring by implantable loop recorders (10%) are rarely used for postablation OAC management. CONCLUSION: A majority of the centers stop OAC in patients with higher CHADS2-VA2SC-score after CTI ablation. There is evidence that this practice might not be safe and lead to an increased number of ischemic strokes during follow-up. This reflects the need for prospective studies to allow for clear guidelines regarding these issues.

Performance of the New BioMonitor 2-AF Insertable Cardiac Monitoring System: Can Better be Worse?

BACKGROUND: Implantable loop recorders (ILR) are valuable tools for the investigation of patients with suspected arrhythmias. The BioMonitor 2-AF is a novel insertable ILR with enhanced atrial fibrillation (AF) detection algorithm and remote monitoring capability. OBJECTIVE: The objective of this first-in-human study with the BioMonitor 2-AF was to analyze course of P-wave sensing performance and R-wave amplitude, prevalence of false and correctly sensed and classified episodes, and effectiveness of remote monitoring. METHODS: All 19 patients who underwent ILR insertion were included in the BIOTRONIK Home Monitoring® system (BIOTRONIK GmbH, Berlin, Germany). Daily changes in P-wave and R-wave sensing were analyzed over 6 weeks. A breathing test (in- and expiration) was performed in two different body positions at baseline and during a 6-week in-house follow-up to investigate alterations of P-wave and R-wave sensing. RESULTS: R-wave amplitude and the high P-wave visibility (94.4%) remained unchanged during the follow-up period. In most patients both an increase and decrease of R-wave amplitude, and in some cases a complete R-wave vector change (31.6%), was documented during the "breathing test." Change of body position did not alter R-wave sensing amplitude mostly. "Breathing test" and change of body position had no effect on P-wave sensing performance. In 15.8% of the patients, misclassification of episodes as AF or high ventricular rates due to P-wave oversensing occurred. No ILR-related complication occurred. Automatic transmission via BIOTRONIK Home Monitoring® was successful 100% of the time. CONCLUSION: This study demonstrates that the BioMonitor 2-AF is a safe and effective tool for continuous cardiac monitoring.

High Patient Satisfaction with Deep Sedation for Catheter Ablation of Cardiac Arrhythmia.

BACKGROUND: Patients' satisfaction with invasive procedures largely relies on periprocedural perception of pain and discomfort. The necessity for intraprocedural sedation during catheter ablation of cardiac arrhythmias for technical reasons is widely accepted, but data on patients' experience of pain and satisfaction with the procedural sedation are scarce. We have assessed patients' pain and discomfort during and after the procedure using a standardized questionnaire. METHODS: One hundred seventeen patients who underwent catheter ablation answered a standardized questionnaire on periprocedural perception of pain and discomfort after different anesthetic protocols with propofol/midazolam with and without additional piritramide and ketamine/midazolam. RESULTS: Patients report a high level of satisfaction with periprocedural sedation with 83% judging sedation as good or very good. The majority of patients was unconscious of the whole procedure and did not recollect experiencing pain. Procedural pain was reported by 7.7% of the patients and 16% reported adverse effects, e.g., postprocedural nausea and episodes of headache. CONCLUSION: The results of our study show that deep sedation during catheter ablation of cardiac arrhythmias is generally well tolerated and patients are satisfied with the procedure. Yet, a number of patients reports pain or adverse events. Therefore, studies comparing different sedation strategies should be conducted in order to optimize sedation and analgesia.

Where There's Smoke, There's Fire? Significance of Atrial Fibrillation in Young Patients.

BACKGROUND: Atrial fibrillation (AF), a disease of the elderly, occasionally occurs at younger age. Pathophysiology of AF in younger patients is diverse, including channelopathies and cardiomyopathies. Data on the significance and complications of AF in young patients are scarce. HYPOTHESIS: Atrial fibrillation is the first manifestation of cardiovascular disease (CVD) in young patients. METHODS: From 11 888 patients in a university hospital database, patients age ≤35 years were identified. A composite of stroke/transient ischemic attack, thromboembolic events, major bleeding, and death was the primary endpoint. Stroke/transient ischemic attack, thromboembolic events, major bleeding, death, AF during follow-up, diagnosis of arrhythmia other than AF, and new diagnosis of any CVD were secondary endpoints. Endpoints were compared between patients with and without comorbidities. RESULTS: We identified 124 patients (29.1± 5 years). Of those, 84 were followed over 48.4 ± 39.8 months. Comorbidities were present in 40.5%. Incidence of the primary endpoint was not different between the groups. Arrhythmias other than AF were more common in patients without comorbidities (36% vs 14.7%; P = 0.032). A supraventricular tachycardia (SVT) was found in 57.1% of patients who underwent electrophysiological testing and was treated with catheter ablation. None of those patients had AF during follow-up. CONCLUSIONS: Atrial fibrillation occurs in young patients with and without structural heart disease. Young AF patients without comorbidities rarely develop CVD during the first years after diagnosis. Yet, an SVT is found in a high proportion of young AF patients; AF may be first manifestation of SVT. Therefore, young patients should undergo further evaluation for SVT.