Supervised Obesity Reduction Trial for AF ablation patients: results from the SORT-AF trial.

AIMS: Weight management seems to be beneficial for obese atrial fibrillation (AF) patients; however, randomized data are sparse. Thus, this study aimed to investigate the influence of weight reduction on AF ablation outcomes. METHODS AND RESULTS: SORT-AF is an investigator-sponsored, prospective, randomized, multicentre, and clinical trial. Patients with symptomatic AF (paroxysmal or persistent) and body mass index (BMI) 30-40 kg/m2 underwent AF ablation and were randomized to either weight-reduction (group 1) or usual care (group 2), after sleep-apnoea-screening and loop recorder (ILR) implantation. The primary endpoint was defined as AF burden between 3 and 12 months after AF ablation. Overall, 133 patients (60 ± 10 years, 57% persistent AF) were randomized to group 1 (n = 67) and group 2 (n = 66), respectively. Complications after AF-ablation were rare (one stroke and no tamponade). The intervention led to a significant reduction of BMI (34.9 ± 2.6-33.4 ± 3.6) in group 1 compared to a stable BMI in group 2 (P < 0.001). Atrial fibrillation burden after ablation decreased significantly (P < 0.001), with no significant difference regarding the primary endpoint between the groups (P = 0.815, odds ratio: 1.143, confidence interval: 0.369-3.613). Further analyses showed a significant correlation between BMI and AF recurrence for patients with persistent AF compared with paroxysmal AF patients (P = 0.032). CONCLUSION: The SORT-AF study shows that AF ablation is safe and successful in obese patients using continuous monitoring via ILR. Although the primary endpoint of AF burden after ablation did not differ between the two groups, the effects of weight loss and improvement of exercise activity were beneficial for obese patients with persistent AF demonstrating the relevance of life-style management as an important adjunct to AF ablation in this setting. TRIAL REGISTRATION NUMBER: NCT02064114.

Predictors of successful complex catheter ablation for persistent atrial fibrillation despite failure of targeted procedural arrhythmia termination.

INTRODUCTION: Procedural atrial fibrillation (AF) termination is considered as a predictor of long-term success after catheter ablation for persistent AF (persAF). However, some patients remain free of arrhythmia recurrences despite failure to achieve AF termination. The objective of this study was to assess long-term outcome and prognostic factors in patients undergoing complex ablation without procedural AF termination. METHODS AND RESULTS: This study comprised 419 patients (63.8 ± 10.2 years, 63.4% male) undergoing complex ablation for persAF. Patients without procedural AF termination (n = 137, 64.2 ± 9.7 years, 63.5% male) were categorized into patients who remained in sinus rhythm (SR) in long-term outcome (SR-group) and patients with recurrence of AF or atrial tachycardia (AT) (AR-group). During a follow-up (FU) of 19.6 ± 14.6 months, the SR-group consisted of 65 (47.5%) and the AR-group of 69 (50.4%) patients. Three patients (2.2%) were lost to FU. Left atrial appendage (LAA) flow velocity and left atrium volume index (LAVI) could be identified as predictors for long-term success. LAA flow velocity and baseline AF cycle length (AFCL) were significantly associated with the type of arrhythmia recurrence (AF vs AT), ie, higher values of both are predictive for AT rather than AF recurrences. Patients with a LAVI < 34.4 mL/m² and significant AFCL increase during the ablation procedure had rather AT than AF recurrences. CONCLUSION: Patients with an arrhythmia-free outcome despite failure of procedural AF termination during complex ablation for persAF are characterized by specific morphological and functional properties that are easy to obtain.

Long-term efficacy and safety of radiofrequency catheter ablation of atrial fibrillation in patients with cardiac implantable electronic devices and transvenous leads.

INTRODUCTION: Long-term efficacy and safety are uncertain in patients with cardiac implantable electronic devices (CIED) and transvenous leads (TVL) undergoing radiofrequency catheter ablation of atrial fibrillation (AF). Thus, we assessed the outcome of AF ablation in those patients during long-term follow-up using continuous atrial rhythm monitoring (CARM). METHODS AND RESULTS: A total of 190 patients (71.3 ± 10.7 years; 108 (56.8% men) were included in this study. At index procedure 81 (42.6%) patients presented with paroxysmal AF and 109 (57.4%) with persistent AF. The ablation strategy included pulmonary vein isolation in all patients and biatrial ablation of complex fractionated electrograms with additional ablation lines, if appropriate. AF recurrences were assessed by CARM- and CIED-related complications by device follow-up. After a mean follow-up of 55.4 ± 38.1 months, freedom of AF was found in 86 (61.4%) and clinical success defined as an AF burden less than or equal to 1% in 101 (72.1%) patients. Freedom of AF was reported in 74.6% and 51.9% (P = 0.006) and clinical success in 89.8% and 59.3% (P < 0.001) of patients with paroxysmal and persistent AF, respectively. In 3 of 408 (0.7%) ablation procedures, a TVL malfunction occurred within 90 days after catheter ablation. During long-term follow-up 9 (4.7%) patients showed lead dislodgement, 2 (1.1%) lead fracture, and 2 (1.1%) lead insulation defect not related to the ablation procedure. CONCLUSION: Our findings using CARM demonstrate long-term efficacy and safety of radiofrequency catheter ablation of AF in patients with CIED and TVL.

Incidence of intracardiac thrombus formation prior to electrical cardioversion in respect to the mode of oral anticoagulation.

AIMS: To evaluate the incidence of newly diagnosed intracardiac thrombi (ICT) in respect to the mode of OAC in patients undergoing cardioversion (CV). METHODS AND RESULTS: We prospectively assessed transesophageal echocardiography (TEE) and OAC therapy prior to CV in AF patients with ≥48-hour duration scheduled for CV. A total of 60 first-time ICT (4.7%) were diagnosed in 1,286 TEE, with highest rate in patients without OAC (9.6% vs. OAC 4.1%, P  =  0.009) and an apparently lower rate in nonvitamin K antagonist anticoagulants (NOAC) therapy compared to vitamin K antagonist (VKA) (2.5% vs. 5.3%, P  =  0.02). VKA therapy control 4 weeks prior to CV was overall average (time in therapeutic range 60%) and patients showed more frequently clinical characteristics and TEE parameters associated with risk for ICT. Even among patients with effective OAC therapy (uninterrupted NOAC and VKA therapy with international normalized ratio (INR) ≥2.0 for 3 weeks), ICT occurred in 2.7%, but with no difference between both groups (P  =  0.22). There was no difference between different types of NOAC. Independent predictors for ICT were history of embolism, hypertension, BMI, absence of OAC, renal function, reduced atrial appendage flow, and presence of spontaneous echo contrast. CONCLUSION: NOAC therapy seems favorable in the overall prevention of ICT, although this is likely to be caused by suboptimal VKA therapy control and differences in the overall health status between VKA and NOAC patients. ICT occurred even with effective OAC therapy suggesting individual TEE-guided cardioversion in patients at risk.

Image integration into 3-dimensional-electro-anatomical mapping system facilitates safe ablation of ventricular arrhythmias originating from the aortic root and its vicinity.

Aims: During ablation in the vicinity of the coronary arteries establishing a safe distance from the catheter tip to the relevant vessels is mandatory and usually assessed by fluoroscopy alone. The aim of the study was to investigate the feasibility of an image integration module (IIM) for continuous monitoring of the distance of the ablation catheter tip to the main coronary arteries during ablation of ventricular arrhythmias (VA) originating in the sinus of valsalva (SOV) and the left ventricular summit part of which can be reached via the great cardiac vein (GCV). Methods and results: Of 129 patients undergoing mapping for outflow tract arrhythmias from June 2014 till October 2015, a total of 39 patients (52.4 ± 18.1 years, 17 female) had a source of origin in the SOV or the left ventricular summit. Radiofrequency (RF) ablation was performed when a distance of at least 5 mm could be demonstrated with IIM. A safe distance in at least one angiographic plane could be demonstrated in all patients with a source of origin in the SOV, whereas this was not possible in 50% of patients with earliest activation in the summit area. However, using the IIM a safe position at an adjacent site within the GCV could be obtained in three of these cases and successful RF ablation performed safely without any complications. Ablation was successful in 100% of patients with an origin in the SOV, whereas VAs originating from the left ventricular summit could be abolished completely in only 60% of cases. Conclusion: Image integration combining electroanatomical mapping and fluoroscopy allows assessment of the safety of a potential ablation site by continuous real-time monitoring of the spatial relations of the catheter tip to the coronary vessels prior to RF application. It aids ablation in anatomically complex regions like the SOV or the ventricular summit providing biplane angiograms merged into the three-dimensional electroanatomical map.

Influence of energy source on early atrial fibrillation recurrences: a comparison of cryoballoon vs. radiofrequency current energy ablation with the endpoint of unexcitability in pulmonary vein isolation.

Introduction: Comparative data of early recurrence rates of atrial fibrillation (ERAF) following second-generation cryoballoon (CB-G2) and radiofrequency current (RFC) ablation for pulmonary vein isolation (PVI) in paroxysmal AF (PAF) are rare. We randomized PAF patients into either PVI with CB-G2 (group 1) or PVI with a combined RFC-approach applying contact force (CF) with the endpoint of unexcitability (group 2) to investigate ERAF. Methods and results: In group 1 (n = 30), CB-G2-PVI was performed. After CF-PVI in group 2 (n = 30), bipolar pacing on the ablation line and additional ablation until unexcitability was conducted. Follow-up included 48 h of in-hospital monitoring followed by 5-day Holter ECGs 1, 2, 3, 6, 12 months postablation to evaluate ERAF. Acute PVI was reached in 100% of group 2 and in 99% of group 1. Shorter procedure durations (98.0 ± 21.9 vs. 114.3 ± 18.7 min, P < 0.05) but extended fluoroscopy times (15.4 ± 3.9 vs. 10.0 ± 4.3 min, P < 0.05) were found in the CB-G2 group. Ten non-severe complications occurred (6 vs. 4 in group 1 and 2, P = 0.73). In group 2, five patients suffered from ERAF vs. seven patients in group 1 (P = 0.67). The time until the occurrence of ERAF was shorter in group 2 (1 day (q1-q3: 1-4.5)) when compared with group 1 (22 (q1-q3: 6-54) days, P = 0.025). Conclusion: ERAF rates were equal among groups; however, they occurred earlier in the initial phase after RFC ablation when compared with CB-G2. PVI utilizing cryoablation is associated with shorter procedure durations but extended fluoroscopy time while being similarly secure.

Sympathetic and Parasympathetic Coactivation Induces Perturbed Heart Rate Dynamics in Patients with Paroxysmal Atrial Fibrillation.

BACKGROUND Recent evidence indicates that sympathetic/parasympathetic coactivation (CoA) is causally linked to changes in heart rate (HR) dynamics. Whether this is relevant for patients with atrial fibrillation (AF) is unknown. MATERIAL AND METHODS In patients with paroxysmal AF (n=26) and age-matched controls, (n=10) we investigated basal autonomic outflow and HR dynamics during separate sympathetic (cold hand immersion) and parasympathetic activation (O2-inhalation), as well as during CoA (cold face test). In an additional cohort (n=7), HR response was assessed before and after catheter-based pulmonary vein isolation (PVI). Ultra-high-density endocardial mapping was performed in patients (n=6) before and after CoA. RESULTS Sympathetic activation increased (control: 74±3 vs. 77±3 bpm, p=0.0098; AF: 60±2 vs. 64±2 bpm, p=0.0076) and parasympathetic activation decreased HR (control: 71±3 vs. 69±3 bpm, p=0.0547; AF: 60±1 vs. 58±2 bpm, p<0.0009), while CoA induced a paradoxical HR increase in patients with AF (control: 73±3 vs. 71±3 bpm, p=0.084; AF: 59±2 vs. 61±2 bpm, p=0.0006), which was abolished after PVI. Non-linear parameters of HR variability (SD1) were impaired during coactivation in patients with AF (control: 61±7 vs. 69±6 ms, p=0.042, AF: 44±32 vs. 32±5 ms, p=0.3929). CoA was associated with a shift of the earliest activation site (18±4 mm) of the sinoatrial nodal region, as documented by ultra-high-density mapping (3442±343 points per map). CONCLUSIONS CoA perturbs HR dynamics and shifts the site of earliest endocardial activation in patients with paroxysmal AF. This effect is abolished by PVI, supporting the value of emerging methods targeting the intrinsic cardiac autonomic nervous system to treat AF. CoA might be a valuable tool to assess cardiac autonomic function in a clinical setting.

Complication Rates of Catheter Ablation of Atrial Fibrillation in Patients Aged ≥75 Years versus <75 Years-Results from the German Ablation Registry.

INTRODUCTION: Despite a rising demand for catheter ablation (CA) of atrial fibrillation (AF) in an elderly population, complication and success rates are not fully elucidated. We sought to compare complication rates of CA of AF in patients ≥75 versus <75 years of age. METHODS AND RESULTS: Patients with symptomatic, drug-refractory AF were prospectively enrolled from January 2007 to 2010 in this multicenter study. A total of 4,449 patients, group 1 ≥75 years and group 2 <75 years (n = 227, age 77.3 ± 2.2 vs. 59.7 ± 9.8 years, 52.0% vs. n = 4,222, 68.9% male, CHA2 DS2 -VASc-Score 3.7 ± 1.0 vs. 1.7 ± 1.2; P < 0.001, respectively), with paroxysmal AF (59.9% in group 1 vs. 63.3% in group 2, P = 0.30), and persistent AF (34.8% in group 1 vs. 29.4% in group 2, P = 0.082) underwent CA of AF. A centralized follow-up was obtained in 4,347 patients by the Institute for Myocardial Infarction Research (IHF, Ludwigshafen). There was a significant difference between periprocedural stroke rates in the elderly versus the younger cohort (1.3% vs. 0.1%, P < 0.01). In-hospital severe nonfatal complications did not differ significantly between the groups (4.4% vs. 2.7%, P = 0.14). Other procedure-related, in-hospital complications were not significantly different. After a mean follow-up of 472 ± 99 days (group 1) and 477 ± 94 days (group 2), no differences were found in complication rates. CONCLUSION: CA of AF in patients ≥75 years is associated with higher in-hospital stroke rates. In a 1-year follow-up, complication rates do not differ between the groups.

Risk stratification of patients with left atrial appendage thrombus prior to catheter ablation of atrial fibrillation: An approach towards an individualized use of transesophageal echocardiography.

INTRODUCTION: The need for transesophageal echocardiography (TEE) before catheter ablation of atrial fibrillation (CA-AF) is still being questioned. The aim of this study is to analyze patients' (patients) risk factors of left atrial appendage thrombus (LAAT) prior to CA-AF in daily clinical practice, according to oral anticoagulation (OAC) strategies recommended by current guidelines. METHODS AND RESULTS: All patients scheduled for CA-AF from 01/2015 to 12/2016 in our center were included and either treated with NOACs (novel-OAC; paused 24-hours preablation) or continuous vitamin K antagonists (INR 2.0-3.0). All patients received a preprocedural TEE at the day of ablation. Two groups were defined: (1) patients without LAAT, (2) patients with LAAT. The incidence of LAAT was 0.78% (13 of 1,658 patients). No LAAT was detected in patients with a CHA2 DS2 -VASc score of ≤1 (n = 640 patients) irrespective of the underlying AF type. Independent predictors for LAAT are: higher CHA2 DS2 -VASc scores (odds ratio [OR] 1.54, 95%-confidence interval [CI]: 1.07-2.23, P = 0.0019), a history of nonparoxysmal AF (OR 7.96, 95%-CI: 1.52-146.64, P = 0.049), hypertrophic cardiomyopathy (HCM; OR 9.63, 95% CI: 1.36-43.05, P = 0.007), and a left ventricular ejection fraction (LVEF) < 30% (OR 8.32, 95% CI: 1.18-36.29, P = 0.011). The type of OAC was not predictive (P = 0.70). CONCLUSIONS: The incidence of LAAT in patients scheduled for CA-AF is low. Therefore, periprocedural OAC strategies recommended by current guidelines seem feasible. Preprocedural TEE may be dispensed in patients with a CHA2 DS2 -VASc score ≤1. However, a CHA2 DS2 -VASc score ≥2, reduced LVEF, HCM, or history of nonparoxysmal AF are independently associated with an increased risk for LAAT.

Active Atrial Function and Atrial Scar Burden After Multiple Catheter Ablations of Persistent Atrial Fibrillation.

BACKGROUND: Extensive and repeated substrate modification (SM) is frequently performed as an ablation strategy in persistent atrial fibrillation (persAF). The effect of these extended ablation strategies on atrial function has not been investigated sufficiently so far. The purpose was to assess atrial function by cardiac magnetic resonance (CMR) and its association with left atrial (LA) scar burden by electroanatomical voltage-mapping after multiple persAF ablation procedures. METHODS: We included 16 persAF patients who had ≥2 SM procedures and a control group (CG) of 21 persAF patients without prior ablation. CMR was performed in sinus rhythm at least 4 weeks after the last cardioversion. Active left and right (RA) atrial emptying fractions (AEF) as well as peak active left atrial appendage (LAA) emptying velocities were obtained by CMR flow measurements. Furthermore, LA scar burden was quantified on electroanatomical voltage maps by the portion of points with local voltage amplitude <0.2 mV. RESULTS: We found median LA-AEF to be lower (13 [9-22] vs 32 [26-36] %, P < 0.001) and median LA scar burden to be higher (40 [20-68] vs nine [3-18] %, P < 0.05) in the SM group compared with the CG. Furthermore, a significant correlation was found between mean LA voltage and LA-AEF (r2 = 0.62, P < 0.001). No significant differences were detected with respect to median RA-AEF (41 [28-48] vs 47 [35-50] %, P = 0.43) and median peak LAA emptying velocities (30 [16-40] vs 17 [13-28] cm/s, P = 0.07). CONCLUSIONS: Active LA function is preserved but significantly impaired and associated with ablation-related LA scar burden after multiple extensive persAF ablations.

Early Detection of Symptomatic Paroxysmal Cardiac Arrhythmias by Trans-Telephonic ECG Monitoring: Impact on Diagnosis and Treatment of Atrial Fibrillation.

INTRODUCTION: Diagnosis of infrequent cardiac arrhythmias (CA) is often unsuccessful using resting or Holter ECG. As early detection and treatment of CA, especially atrial fibrillation (AF), has implications on patients' treatment and outcome, we investigated, whether self-guided, trans-telephonic event-recorder monitoring (Tele-ECG) improves diagnosis and influences treatment options. METHODS: Between 2009 and 2014, 790 patients (54 ± 18 years, 40% male; no history of CA: 582, known AF: 179, other CA: 29) presented with recurrent symptoms suggestive of CA and were screened by Tele-ECG (17.3 ± 26.9 days). A total of 11,775 ECGs were transmitted via a 24-hour telephone hotline including documentation of the respective symptoms. RESULTS: In 73% of patients, CA was documented at the time of symptoms: sinus tachycardia 23%, premature ventricular beats 19%, AF 14%, supraventricular tachycardia 9%, sinus bradycardia 5%, sinus arrhythmia 2%, and AV block II 1%. The mean time until the first symptomatic episode occurred was 6.9 ± 15.3 days (median 2.5 days). The first documented arrhythmia occurred on average after 7.7 ± 14.1 days (median 3 days). In patients with AF (n = 110), 44% was newly diagnosed. According to the Tele-ECG diagnosis, AF ablation was performed in 27% of these patients, 7% electrical cardioversion, and in 30% antiarrhythmic therapy was initiated. In 65% of the patients with recurrence of known AF, (re-)ablation was performed or recommended and in 16% antiarrhythmic therapy was modified. CONCLUSIONS: Tele-ECG monitoring is effective in the diagnosis of suspected symptomatic CA. A diagnosis can usually be achieved within 1 week and has implications on patients' care.

Characterization, Mapping, and Ablation of Complex Atrial Tachycardia: Initial Experience With a Novel Method of Ultra High-Density 3D Mapping.

INTRODUCTION: Conventional mapping of complex atrial tachycardias (ATs) can be challenging. Thus, we evaluated feasibility and utility of a novel, ultra high-density 3D mapping approach to characterize and map AT in these cases. METHODS AND RESULTS: Overall, 21 patients (67.4 ± 7.6 years; male: 52.4%, 1.9 ± 1.4 previous ablation procedures) with documented AT referred to our center underwent catheter ablation including ultra high-density mapping using a novel 64-electrode mini-basket catheter and an adjunctive 3D mapping system. A total of 24 AT (20 left atrial, 4 right atrial AT) were analyzed in 19 cases. In 2 patients, map acquisition failed due to scarce local electrograms and unstable AT cycle length, respectively. Underlying mechanisms were focal (n = 3), as well as local (n = 8) and macro (n = 13) reentry tachycardias with a mean cycle length of 311.8 ± 67.7 milliseconds. The analysis of propagation waves, activation and voltage revealed complex activation patterns and allowed for the identification of critical sites of AT initiation or maintenance without the need for further mapping techniques. In all cases critical sites could be verified by successful consecutive ablation. Mean mapping time was 19.4 ± 7.6 minutes, mean number of mapping points was 19,217 ± 10,270. Radiofrequency application until first effect was 165.1 ± 374.2 seconds; total procedure time was 157.6 ± 51.4 minutes, fluoroscopy time 21.7 ± 13.8 minutes, and total radiofrequency duration 1,016 ± 951.9 seconds, respectively. No severe complications occurred. CONCLUSION: Ultra high-density mapping of complex AT is safe and feasible. Further, it enables detailed insight into AT mechanisms. Critical AT sites can be identified precisely in order to guide successful catheter ablation.

Propofol sedation administered by cardiologists for patients undergoing catheter ablation for ventricular tachycardia.

AIMS: Propofol sedation has been shown to be safe for atrial fibrillation ablation and internal cardioverter-defibrillator implantation but its use for catheter ablation (CA) of ventricular tachycardia (VT) has yet to be evaluated. Here, we tested the hypothesis that VT ablation can be performed using propofol sedation administered by trained nurses under a cardiologist's supervision. METHODS AND RESULTS: Data of 205 procedures (157 patients, 1.3 procedures/patient) undergoing CA for sustained VT under propofol sedation were analysed. The primary endpoint was change of sedation and/or discontinuation of propofol sedation due to side effects and/or haemodynamic instability. Propofol cessation was necessary in 24 of 205 procedures. These procedures (Group A; n = 24, 11.7%) were compared with those with continued propofol sedation (Group B; n = 181, 88.3%). Propofol sedation was discontinued due to hypotension (n = 22; 10.7%), insufficient oxygenation (n = 1, 0.5%), or hypersalivation (n = 1, 0.5%). Procedures in Group A were significantly longer (210 [180-260] vs. 180 [125-220] min, P = 0.005), had a lower per hour propofol rate (3.0 ± 1.2 vs. 3.8 ± 1.2 mg/kg of body weight/h, P = 0.004), and higher cumulative dose of fentanyl administered (0.15 [0.13-0.25] vs. 0.1 [0.05-0.13] mg, P < 0.001), compared with patients in Group B. Five (2.4%) adverse events occurred. CONCLUSION: Sedation using propofol can be safely performed for VT ablation under the supervision of cardiologists. Close haemodynamic monitoring is required, especially in elderly patients and during lengthy procedures, which carrying a higher risk for systolic blood pressure decline.

Interventional management of recurrent paroxysmal atrial fibrillation despite isolated pulmonary veins: impact of an ablation strategy targeting inducible atrial tachyarrhythmias.

AIMS: Pulmonary vein isolation (PVI) is an effective treatment option for paroxysmal atrial fibrillation (PAF). Reconnection of pulmonary veins (PVs) is the predominant cause for recurrence of PAF. However, treatment of patients with recurrence of PAF despite isolated PV in the absence of extra-PV foci remains challenging. METHODS AND RESULTS: Of 265 patients undergoing repeat catheter ablation (CA) for recurrence of PAF 21 (8%) patients (14 men, age 58 ± 14 years) showed no reconnection of PV. Therefore, inducibility of sustained atrial arrhythmias was tested. If sustained atrial fibrillation (AF) or sustained atrial tachycardia (AT) was induced, patients underwent CA. During follow-up (FU), Holter- and Tele-electrocardiogram were performed. In 19 (91%) of 21 patients, sustained atrial arrhythmias [16 (84%) AF; 3 (15%) patients AT] were induced. One patient showed PAF. Eighteen patients underwent CA aiming for termination of induced arrhythmia. In 14 (77%) patients, termination into sinus rhythm was achieved. Despite extensive CA, three (16%) patients were externally cardioverted. No periprocedural complications occurred. During 21.2 ± 6.8-month FU, 10 (53%) patients were free of any arrhythmia. Paroxysmal atrial fibrillation recurred in 4 (21%) and AT in 5 (26%) patients. One patient showed persistent AF. Repeat CA was scheduled and successfully performed for these patients. CONCLUSION: In patients with recurrence of PAF despite isolated PV, termination of induced atrial arrhythmias can be achieved in most patients by defragmentation and AT ablation. Moreover, this ablation strategy results in favourable mid-term outcome results.

Use of antiarrhythmic drugs during ablation of persistent atrial fibrillation: observations from a large single-centre cohort.

Catheter ablation of complex fractionated atrial electrograms (CFAE), also known as defragmentation ablation, may be considered for the treatment of persistent atrial fibrillation (AF) beyond pulmonary vein isolation (PVI). Concomitant antiarrhythmic drug (AAD) therapy is common, but the relevance of AAD administration and its optimal timing during ablation remain unclear. Therefore, we investigated the use and timing of AADs during defragmentation ablation and their possible implications for AF termination and ablation success in a large cohort of patients. Retrospectively, we included 200 consecutive patients (age: 61 ± 12 years, LA diameter: 47 ± 8 mm) with persistent AF (episode duration 47 ± 72 weeks) who underwent de novo ablation including CFAE ablation. In all patients, PVI was performed prior to CFAE ablation. The use and timing of AADs were registered. The follow-ups consisted of Holter ECGs and clinical visits. Termination of AF was achieved in 132 patients (66 %). Intraprocedural AADs were administered in 168/200 patients (84 %) 45 ± 27 min after completion of PVI. Amiodarone was used in the majority of the patients (160/168). The timing of AAD administration was predicted by the atrial fibrillation cycle length (AFCL). At follow-up, 88 patients (46 %) were free from atrial arrhythmia. Multivariate logistic regression analysis revealed that administration of AAD early after PVI, LA size, duration of AF history, sex and AFCL were predictors of AF termination. The administration of AAD and its timing were not predictive of outcome, and age was the sole independent predictor of AF recurrence. The administration of AAD during ablation was common in this large cohort of persistent AF patients. The choice to administer AAD therapy and the timing of the administration during ablation were influenced by AFCL, and these factors did not significantly influence the moderate single procedure success rate in this retrospective analysis.

Implantable loop recorder monitoring after concomitant surgical ablation for atrial fibrillation (AF): insights from more than 200 continuously monitored patients.

Different follow-up methods have been used to report success rates after AF ablation. Recent studies have shown that intermittent rhythm monitoring underestimates the actual AF recurrence rate. We therefore report our experience with continuous rhythm monitoring by implantable loop recorder (ILR) in a large patient cohort. Between 09/2008 and 12/2012, 343 cardiac surgical patients underwent concomitant surgical AF ablation. ILR implantation was performed in 206 patients. ILR interrogation was accomplished at 3, 6 and 12 months postoperatively. Successful ablation was defined as AF Burden <0.5 %. Primary outcome of the study was freedom from AF at 12-month follow-up. Mean patient's age was 70.5 ± 7.4 years. No major ablation- or ILR-related complications occurred. In 4 patients (1.9 %) ILR had to be explanted due to ILR-related wound infection (n = 2) or chronic pain (n = 2). Survival rate at 1-year follow-up was 96.6 %. Freedom from AF rate after 1-year follow-up was 68.5 and 63.6 % off antiarrhythmic drugs, respectively. Statistically significant predictors for successful ablation at 1-year follow-up were smaller LA diameter, shorter duration of AF and preoperative paroxysmal AF. Demographic data, indication for surgery, lesion set and used energy source had no impact on freedom from AF after 1 year. Continuous ILR monitoring after concomitant surgical AF ablation was safe and feasible, with registered freedom from AF rate of 68.5 % at 1-year follow-up. Thus continuous rhythm monitoring provides reliable outcome data and helps to guide antiarrhythmic therapy.

Pulse wave analysis of the aortic pressure waveform in patients with vasovagal syncope.

Vascular reflex mechanisms contribute to vasovagal syncope. However, the alterations in central haemodynamics in patients with vasovagal syncope are unknown. 30 consecutive patients (36.5 ± 15 years, 14 females) with recurrent vasovagal syncope (VVS) and a positive tilt table test were compared to 39 age- and sex-matched controls (36.9 ± 16 years, 15 females) with a negative tilt table result and no history of syncope. Central aortic pressure parameters including augmentation index and central pulse pressure as markers of aortic stiffness were generated non-invasively by applanation tonometry of the radial artery and use of a validated mathematical transfer function. No difference in aortic augmentation index was observed between groups. (VVS 9 ± 2.6 vs. Control 11 ± 2.4, p = 0.8). However, in patients with vasovagal syncope the aortic pressure waveform significantly differed from healthy controls. A prolonged time to the peak of aortic pressure wave (aortic T2) was observed in patients with vasovagal syncope (226 ± 24 vs. 208 ± 21 ms, p = 0.001). Furthermore time to the first shoulder of the aortic pressure wave (aortic T1) was slightly shorter compared to healthy controls, but did not reach statistical significance (106 ± 22 vs. 110 ± 12 ms, p = 0.33). Patients with vasovagal syncope have an altered aortic pressure waveform at rest, but no signs of elevated aortic stiffness. The underlying mechanisms for these findings may potentially result from a complex imbalance of the autonomic nervous system with a continuous deregulation of the sympathetic and parasympathetic reflex arcs.

Loss of Pace Capture on the Ablation Line During Pulmonary Vein Isolation versus "Dormant Conduction": Is Adenosine Expendable?

INTRODUCTION: Permanent pulmonary vein isolation (PVI) remains an essential goal of ablation therapy in patients with atrial fibrillation. Aim of this study was the intraindividual comparison of unexcitability to pacing along the ablation line versus dormant conduction (DC) as additional procedural endpoints. METHODS: A total of 58 patients with paroxysmal atrial fibrillation (PAF) underwent PVI by circumferential ablation of ipsilateral pulmonary veins (PVs), followed by testing for DC by adenosine administration. Irrespective of the presence of DC, pacing along the ablation line for left atrium capture was performed and additional radio frequency energy applied if necessary. PVs with initial DC were retested after achieving unexcitability. RESULTS: PVI was achieved in 224 of 224 PVs. In 33 of 224 PVs (15%) DC was revealed. At 92 of 112 ablation lines (82%) sites of excitability were found. Three (9%) of the initial 33 PVs with DC showed further DC after achieving unexcitability at repeated testing. Thirty-two of 33 assumed areas of unmasked PV-LA reconduction as revealed by DC-testing showed a corresponding site of excitability on the ablation line. After a follow-up of 11.6 ± 3.4 months 79% of patients were free of arrhythmia. CONCLUSIONS: Pacing for unexcitability can safely identify potential sites of DC and even sites that would have not been detected by testing for DC. Unexcitability, therefore, serves as a suitable and safe procedural endpoint not only for patients with contraindications to adenosine administration. Our data suggest that adenosine may be expendable when achieving unexcitability along the ablation line.

Reduction of Radiation Exposure in Atrial Fibrillation Ablation Using a New Image Integration Module: A Prospective Randomized Trial in Patients Undergoing Pulmonary Vein Isolation.

INTRODUCTION: Recently, a new image integration module (IIM, CartoUnivu™ Module) has been introduced to combine and merge fluoroscopy images with 3-dimensional-(3D)-electroanatomical maps (Carto® 3 System) into an accurate 3D view. The aim of the study was to investigate the influence of IIM on the fluoroscopy exposure during pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) in a prospective randomized trial. METHODS AND RESULTS: Between June and November 2014, a total of 60 patients with PAF (73.3% male, 64.0 ± 9.2 years), who underwent PVI with the endpoint of unexcitability of the ablation line, were randomized to either a conventional 3D mapping system (Carto® 3 System) or to an additional IIM on the basis of an assumed reduction of fluoroscopy exposure by the use of IIM. There were no significant differences in baseline characteristics. The median ablation procedure time was identical in both groups (140.7 ± 27.8 minutes vs. 140.8 ± 39.5 minutes; P = 0.851). A significant decrease of mean fluoroscopy time from 11.9 ± 2.1 to 7.4 ± 2.6 minutes (P < 0.0006) and median fluoroscopy dose from 882.9 to 476.5 cGycm(2) (P < 0.001) was achieved. The main reduction of radiation could be realized during creation of the 3D-map. No major complications occurred during the procedures. After a median follow-up of 125.7 ± 45.6 days 80% of the patients were free from any atrial arrhythmias. CONCLUSION: CartoUnivu™ module easily integrates into the workflow of PVI with the endpoint of unexcitability of the ablation line without prolonging the procedure time. It is associated with a marked reduction in fluoroscopic dose when compared to a conventional 3D mapping system.

Impact of structural heart disease on the acute complication rate in atrial fibrillation ablation: results from the German Ablation Registry.

INTRODUCTION: Catheter ablation (CA) has emerged as a widespread therapeutic option in the treatment of atrial fibrillation (AF). Currently, no safety data with regard to the impact of the underlying structural heart diseases (SHD) are available. We sought to assess the risk for acute and long-term complications during CA of AF in relation to underlying SHD. METHODS AND RESULTS: We included 6,211 patients in a prospective registry undergoing CA of AF in 41 nationwide centers. All patients were divided into 4 groups according to the underlying heart disease: No SHD (69.4%), hypertensive heart disease (HHD) (12.0%), coronary artery disease (CAD) (15.1%), and cardiomyopathy (CM) (3.6%). In univariate analysis, patients with HHD had an overall complication rate of 7.28%, whereas patients without an SHD had a significantly lower rate of 6.01% (P < 0.01). Multivariate analysis revealed that HHD (adjusted odds ratio [OR]: 1.97 [95% confidence interval (CI): 1.02-3.83], P = 0.0442) and age (years; OR: 1.04 [95% CI: 1.01-1.07], P = 0.0155) were independent predictors of severe, nonfatal complications and death. Other SHD including CAD (OR: 1.48 (0.73-3.00), P = 0.2797) and CM (OR: 2.37 [0.70-7.99], P = 0.1630) failed to reach statistical significance. Male sex was protective (OR: 0.47 [95% CI: 0.27-0.81], P = 0.0062). CONCLUSION: In general, CA of AF has a low number of severe complications. In our prospective registry HHD emerged as an independent predictor of severe, nonfatal complications during AF ablation but other SHD including CAD and CM did not. The influence of HHD on the complication rate should be considered in patient selection.