Reduction of Radiation Exposure in Atrioventricular Nodal Reentrant Tachycardia Ablations Using an Electroanatomical Mapping System With Fluoroscopy Integration Module.

Introduction: Atrioventricular nodal reentrant tachycardia (AVNRT) is a common supraventricular tachycardia. Current guidelines recommend electrophysiology study (EPS) and ablation, which have been proven to show high success rates with very low complication rates. Usually, ablation of AVNRT is performed conventionally using only fluoroscopy. Electroanatomical mapping systems (EMS) are widely used in complex arrhythmias. One of their advantages is their potential in decreasing the need of fluoroscopy time (FT). In this study we analyzed patients undergoing either conventional AVNRT ablation or by using an EMS with a fluoroscopy integrating system (FIS). Materials and Methods: We included 119 patients who underwent AVNRT ablation in our study. Eighty-nine patients were ablated conventionally using only fluoroscopy, 30 patients were ablated using EMS + FIS. Results: We found that the use of EMS + FIS led to a significant reduction of FT (449.90 ± 217.21 vs. 136.93 ± 109.28 sec., p < 0.001) and dose-area-product (DAP, 268.27 ± 265.20 vs. 41.07 ± 27.89 µGym2, p < 0.001) without affecting the procedure time (PT, 66.55 ± 13.3 vs. 67.33 ± 13.81 min, p = 0.783). Furthermore, we found no significance with regard to complications. Conclusion: The use of EMS+FIS is safe and feasible. It leads to a significant reduction of both FT and DAP without affecting PT and safety. Hence, EMS + FIS is beneficial for both the operator and the patients by reducing the radiation exposure.

Wearable Cardioverter-Defibrillator Used as a Telemonitoring System in a Real-Life Heart Failure Unit Setting.

BACKGROUND: In patients with reduced left ventricular ejection fraction (LVEF) who are at risk of sudden cardiac death, a wearable cardioverter-defibrillator (WCD) is recommended as a bridge to the recovery of LVEF or as a bridge to the implantation of a device. In addition to its function to detect and treat malignant arrhythmia, WCD can be used via an online platform as a telemonitoring system to supervise patients' physical activity, compliance, and heart rate. METHODS: We retrospectively analyzed 173 patients with regard to compliance and heart rate after discharge. RESULTS: Mean WCD wearing time was 59.75 ± 35.6 days; the daily wearing time was 21.19 ± 4.65 h. We found significant differences concerning the patients' compliance. Men showed less compliance than women, and younger patients showed less compliance than patients who were older. Furthermore, we analyzed the heart rate from discharge until the end of WCD prescription and found a significant decrease from discharge to 4, 8, or 12 weeks. CONCLUSION: WCD can be used as a telemonitoring system to help the involved heart failure unit or physicians attend to and adjust the medical therapy. Furthermore, specific patient groups should be educated more intensively with respect to compliance.

Influence of excess weight and obesity on performance and outcome of pulmonary vein isolation with the cryoballoon.

Pulmonary vein isolation (PVI) has become a cornerstone therapy in the treatment of atrial fibrillation (AF). Patients with overweight or obesity suffer more often from AF, and studies investigating the safety and feasibility of PVI in these patients have shown varying results. In this study we analyzed PVI performed with the 2nd generation cryoballoon (CB) with regard to safety, procedure and fluoroscopy time in patients with normal weight, overweight and obesity. We analyzed 228 consecutive patients treated with CB PVI in our hospital in 2018 and 2019. Fifty nine (25.88%) patients presented with normal weight (body mass index (BMI) of <25), 115 (50.44%) patients with overweight (BMI between 25 and 29.9) and 54 (23.68%) were obese patients (BMI >30). All pulmonary veins (PV) were isolated successfully. Concerning procedural parameters, neither complications, procedural time, nor fluoroscopy time differed significantly. There was a significant increase of dose area product (DAP) in obese patients compared to normal weight and overweight patients (2035.5 ± 1930.1 µGym2 vs. 975.3 ± 814.9 vs. 1325.1 ± 2081.3, p = 0.001) but no significant difference between overweight and normal weight patients (p = 0.611). Our follow-up data of 168 patients (73.68%) observed for 12 months showed no differences in the recurrence of AF in the three BMI groups [80.9% vs. 83.3% (p = 0.733) vs. 86.55% (p = 0.460)]. In conclusion, CB PVI in overweight and obese patients is safe with similar levels of complications and recurrence of AF as patients of normal weight. However, obese patients and operators are exposed to higher radiation doses.

Long-term impact of a bonus freeze on clinical outcome: Analysis of effective and non-effective bonus freezes in cryoballoon ablation.

PURPOSE: Data on bonus freeze characteristics and their impact on complication rates and long-term clinical outcome are limited. METHODS: Pulmonary vein isolation (PVI) using a 28 mm 2nd-generation cryoballoon (CB) was performed in 169 patients (pts). The isolation temperatures, time to isolation and minimal temperatures of the cryoapplications were documented. RESULTS: The study included 92 pts who received one bonus freeze after PVI in group I and 77 pts who did not receive a bonus freeze in group II. After a mean follow-up time of 19.0±8.6 months in group I and 16.4±7.5 months in group II, 67 of 92 pts (72.8%) and 49 of 75 pts available to follow up (65.3%; p = 0.221) were free of atrial tachyarrhythmia, respectively. Phrenic nerve palsy occurred in 5.4% of the pts in group I (5/92 pts) and 1.3% of the pts in group II (1/77 pts; p = 0.22). Both the mean nadir temperatures of the bonus freezes and mean nadir temperatures of the isolation freezes differed significantly between the recurrent and non-recurrent pts in group I. The predilection sites of the reconduction for both groups were the inferior aspect of the inferior pulmonary veins. CONCLUSION: The impact of a bonus freeze on long-term clinical outcome was not significant for two reasons: 1) The necessity of a bonus freeze was low because the long-term clinical success rate without a bonus freeze was high; and 2) the majority of bonus freezes, especially at the predilection sites, such as the inferior PV, appeared to be ineffective.

Cryoballoon ablation for pulmonary vein isolation in patients with atrial fibrillation: preliminary results using novel short-tip cryoballoon.

PURPOSE: In this study, we aimed to report our preliminary experience regarding the impact of the novel short-tip (ST) cryoballoon (CB) on procedural efficacy and signal quality during pulmonary vein (PV) isolation for both paroxysmal and persistent atrial fibrillation. METHODS: Between March, 2015, and August, 2015, we enrolled a total of 64 patients (47 patients male, 73 %) with a mean age of 60 ± 11 years. In the study population, 31 patients (48 %) underwent PVI using Advance (ADV) CB and 33 (52 %) patients with ST CB. In all patients, a 28-mm balloon was used. RESULTS: Acute procedural success rates were 100 % for the entire study population. A statistically insignificant increase in the percentage of PV signal recordings was observed with ST CB in all PVs compared to ADV CB [88 vs. 81 % for left superior PV (LSPV), 82 vs. 78 % for left inferior PV (LIPV), 85 vs. 84 % for right superior PV (RSPV), 82 vs. 71 % for right inferior PV (RIPV), p < 0.05]. Additionally, the difference in minimum temperature reached during the procedure per PV was not statistically significant between ST CB and ADV CB except the LIPV (LSPV -44.2 ± 5.9 vs. -45.6 ± 5.3 °C, p = 0.970; LIPV -38.7 ± 4.6 °C vs -44.6 ± 6.8 °C, p < 0.001; RSPV -45.6 ± 7.4 °C vs.-47.2 ± 6.1 °C, p = 0.168; RIPV -41.4 ± 5.1 °C vs.-43.7 ± 6.3 °C, p = 0.360). Time to isolation for each PV was similar between ST and ADV CB (p > 0.05). CONCLUSION: Our preliminary findings indicated similar acute procedural success for the novel ST CB compared with second generation ADV CB. The increase in the ratio of PV signal recordings obtained during the PVI using the novel ST CB was not significant.

Characterization of Electrical Reconnection Following Pulmonary Vein Isolation Using First- and Second-Generation Cryoballoon.

BACKGROUND: Second-generation cryoballoon (CB-2) is associated with improved outcomes for pulmonary vein isolation (PVI) compared to first generation (CB-1). However, data regarding the predictors of pulmonary vein (PV) electrical reconnection are limited. In this study, we aimed to characterize the predilection sites and predictors of reconnection in patients with recurrent atrial tachyarrhythmia (ATa) after PVI using CB-1 and CB-2. METHODS: A total of 59 patients (mean age: 62 ± 11 years and 66% male) with recurrent ATa after previous CB-PVI, using either a 28-mm CB-1 or CB-2, underwent repeat ablation. PV reisolation was performed by irrigated radiofrequency ablation using three-dimensional electroanatomical mapping systems. RESULTS: Electrical PV reconnection was detected in 10 of 11 (91%) of CB-1 patients compared to 41 of 48 (85%) of CB-2 patients. Time to redo procedure after index CB-1 was 8.9 ± 10.2 months and 11.2 ± 7.0 months in CB-2. Bonus freeze was applied in all patients with CB-1 and 41% of the patients with CB-2. Superior quadrants of both superior PVs and inferior quadrants of the both inferior PVs exhibited higher predilection for conduction compared to other quadrants (P < 0.001). Multivariate binary logistic analysis revealed that right inferior PV (RIPV; odds ratio [OR]: 1.52, 95% confidence interval [CI]: 1.09-2.13, P = 0.014) and minimum temperature (OR: 1.09, 95% CI: 1.03-1.15, P = 0.004) were the independent predictors of electrical reconnection after CB-2 ablation. CONCLUSION: Conduction gaps after CB-1 and CB-2 were higher in inferior PVs compared to superior PVs. The RIPV and minimum CB temperature were independent predictors of PV electrical reconnection after CB-2.

The Total Incidence of Complications and the Impact of an Anticoagulation Regime on Adverse Events After Cryoballoon Ablation of Atrial Fibrillation: A Single-Center Study of 409 Patients.

AIM: Data evaluating the complications of pulmonary vein isolation (PVI) using second-generation cryoballoons (CB) related to different anticoagulation regimes are limited. This study evaluates the total complications and the impact of novel oral anticoagulants (NOACs) compared to phenprocoumon on adverse events in the setting of PVI using CB. METHODS AND RESULTS: PVI was performed using second-generation CB by two experienced investigators. A total of 409 patients (58.9% male; mean age = 61 ± 10 years) with atrial fibrillation were included in this study. In group I, 150/409 (36.7%) patients received phenprocoumon therapy, and in group II, 259/409 (63.3%) patients were treated with NOACs (rivaroxaban: n = 193; dabigatran: n = 48; and apixaban: n = 18). In both groups, the rates of major complications were similar (group I [phenprocoumon]: four pts (2.7%) vs. Group II [NOACs]: seven pts (2.7%); P = 0.999). In this cohort, 275 patients were ablated with the bonus freeze protocol, and 134 patients were ablated without bonus freezes. The procedure duration significantly decreased with the bonus freeze protocol from 102.3 ± 24.6 min to 68.5 ± 16.2 min (P < 0.001). The impact of the bonus freeze on the postprocedural increase of C-reactive protein (CRP) levels was significant compared to the postprocedural CRP levels after procedures without the bonus freeze protocol (postprocedural CRP level+ bonus protocol: 1.6 ± 1.2 mg/L vs. postprocedural CRP level+ nonbonus protocol: 1.3 ± 1.3 mg/L; P = 0.04). CONCLUSION: The incidence of adverse events in PVI using the second-generation CB with the periprocedural administration of NAOCs was not significantly different compared to phenprocoumon. Further, large-scale randomized studies are needed to evaluate the safety of two anticoagulation regimes comparing vitamin K antagonists and NOACs, as well as different NOAC regimes, in patients undergoing PVI using cryoballoon ablation.

Rotational Angiography Based Three-Dimensional Left Atrial Reconstruction: A New Approach for Transseptal Puncture.

AIM: Rotational angiography is a well-known method for the three-dimensional (3-D) reconstruction of left atrium and pulmonary veins during left-sided atrial arrhythmia ablation procedures. In our study, we aimed to review our experience in transseptal puncture (TSP) using 3-D rotational angiography. METHODS: We included a total of 271 patients who underwent atrial fibrillation ablation using cryoballoon. Rotational angiography was performed to get the three-dimensional left atrial and pulmonary vein reconstructions using cardiac C-arm computed tomography. The image reconstruction was made using the DynaCT Cardiac software (Siemens, Erlangen, Germany). RESULTS: The mean age of the study population was 61 ± 10 years. The indications for left atrial arrhythmia ablation were paroxysmal AF in 140 patients (52%) and persistent AF patients in 131 (48%) patients. The success rate of TSP using only rotational guidance was (264/271 patients, 97.4%). In the remaining seven patients, transesophageal guidance was used after the initial attempt due to thick interatrial septum in five patients and difficult TSP due to abnormal anatomy and mild pericardial effusion in the remaining two patients. Mean fluoroscopy dosage of the rotational angiography was 4896.4 ± 825.3 µGym(2). The mean time beginning from femoral vein puncture to TSP was 12.3 ± 5.5 min. CONCLUSION: TSP guided by rotational angiography is a safe and effective method. Our results indicate that integration of rotational angiographic images into the real-time fluoroscopy can guide the TSP during the procedure.

Cryoballoon Ablation for Pulmonary Vein Isolation in Patients With Persistent Atrial Fibrillation: One-Year Outcome Using Second Generation Cryoballoon.

BACKGROUND: Data regarding the freedom from atrial fibrillation (AF) in the follow-up of persistent AF patients is limited. The second-generation cryoballoon has better cooling properties compared with first-generation cryoballon. In this study, we aimed to assess the medium-term efficacy of second-generation cryoballoon in patients with persistent AF. METHODS AND RESULTS: A total of 100 patients (63±10 years, 80% male) with symptomatic persistent AF, despite ≥1 antiarrhythmic drug(s), who were scheduled for pulmonary vein isolation using second-generation cryoballoon were enrolled in this study. Follow-up was based on outpatient clinic visits, including Holter ECGs. Recurrence was defined as a symptomatic or documented arrhythmia episode of >30 seconds excluding a 3-month blanking period. As a result, 393 pulmonary veins (7 patients with common ostium) were successfully isolated. Mean procedural and fluoroscopy times were 96.2±21.3 and 19.7±6.7 minutes, respectively. Phrenic nerve palsy occurred in 3% (3/100) of the patients. At a mean follow-up duration of 10.6±6.3 months, 67% of the patients were in sinus rhythm. Stepwise multivariable Cox proportional hazard regression analysis showed that early AF recurrence (hazard ratio 3.83, 95% confidence interval 1.91-7.68, P<0.001) was the only independent predictor for late AF recurrence apart from other clinical and echocardiographic variables. CONCLUSIONS: Our findings indicated that second-generation cryoballoon use is associated with favorable outcomes in patients with persistent AF. Recurrence at blanking period was the only predictor of long-term AF recurrence.

Luminal esophageal temperature rise and esophageal lesion formation following remote-controlled magnetic pulmonary vein isolation.

BACKGROUND: Remote magnetic pulmonary vein isolation (PVI) demonstrates comparable success rate to manual ablation, but thermal effects on esophageal tissue remain undefined. OBJECTIVE: The purpose of this study was to evaluate the potential thermal effects on esophageal tissue during remote magnetic wide-area circumferential pulmonary vein isolation (CPVI). METHODS: Twenty-five patients (23 men, age 57 ± 10 years) in the magnetic navigation system (MNS) group and 25 control subjects (15 men, age 61 ± 12 years) with drug-refractory paroxysmal or persistent atrial fibrillation underwent CPVI. A magnetic 3.5-mm irrigated-tip catheter (NaviStar ThermoCool RMT, Biosense Webster) and a nonmagnetic 3.5-mm irrigated-tip catheter (NaviStar ThermoCool, Biosense Webster) were used in the MNS and control group, respectively. A temperature probe (SensiTherm, St. Jude Medical), containing 3 thermocouples was placed in close proximity to the ablation site monitoring luminal esophageal temperature (LET). LET changes did not guide therapy. Postprocedural esophagogastroduodenoscopy (EGD) was performed in all patients. RESULTS: Successful CPVI was achieved in all patients. No esophageal lesions, minimal lesions, or ulcerations were found in 16 of 25 (64%), 7 of 25 (28%), and 2 of 25 (8%) in the MNS group and in 14 of 25 (56%), 10 of 25 (40%), and 1 of 25 (4%) patients in the control group, respectively. No atrioesophageal fistula occurred. Mean maximum LET in the magnetic group was 43.7°C ± 3.7°C compared to 45.4°C ± 3.5°C in the manual control group (P = .09). CONCLUSION: Remote magnetic PVI is associated with significant rise in LET and development of thermal esophageal lesions. In the MNS group, higher LET recordings were more likely to cause esophageal injury, whereas this association was not seen in the manual group despite a tendency toward higher mean maximum LET recordings.

Catheter ablation for ventricular tachycardia after failed endocardial ablation: epicardial substrate or inappropriate endocardial ablation?

BACKGROUND: The substrate of myocardial ventricular tachycardia (VT) may involve the subepicardial myocardium. OBJECTIVE: The purpose of this study was to assess the incidence of epicardial substrates in patients with a previously failed endocardial ablation attempt for VT as well as the safety and effectiveness of epicardial ablation. METHODS: Using an electroanatomic mapping system, endocardial and epicardial maps were acquired. Irrigated radiofrequency current ablations of all inducible VTs were performed. RESULTS: Between 2005 and 2009, 59 patients with or without structural heart disease underwent epicardial VT ablation. Pericardial access failed in 3 (5%) of these patients. Of the remaining 56 patients, an epicardial substrate was found in 41 (73%). Overall, acute success was achieved in 46 (78%) of 59 patients, with complete VT abolition in 27 (46%) and partial abolition in 19 (32%). Successful outcomes were the result of endocardial ablation only in 14 (24%) patients, epicardial ablation in 21 (36%), and endocardial/epicardial in 11 (19%). Ablation failed to prevent reinduction in 8 (13%) patients, and VTs were noninducible prior to ablation in 5 (8%). Two periprocedural deaths occurred, one after right ventricular perforation and one due to electromechanical dissociation. Hepatic bleeding occurred in two patients. Recurrence of any VT occurred in 27 (47%) of 57 surviving patients during median follow-up of 362 days (q1-q3; 180-468 days). Repeat epicardial mapping was not feasible due to adhesions in 3 (25%) of 12 patients. CONCLUSION: In patients with a previously failed endocardial VT ablation, epicardial mapping reveals a VT substrate in nearly three fourths of all patients, and epicardial ablation is required for successful VT abolition in more than half of patients. However, life-threatening complications may occur. Repeat epicardial access was not possible in 25% due to local pericardial adhesions.

Unexpected high incidence of esophageal injury following pulmonary vein isolation using robotic navigation.

INTRODUCTION: Robotic navigation (RN) is a novel technology for pulmonary vein isolation (PVI). We investigated the incidence of thermal esophageal injury using RN with commonly used power settings in comparison to manual PVI procedures. methods: Thirty-nine patients underwent circumferential PVI using a 3.5-mm irrigated-tip-catheter. In the manual (n = 25) and the RN(1) group (n = 4) power was limited to 30 W (17 mL/min flow, maximal temperature 43 degrees C, max. 30 sec/spot) at the posterior left atrial (LA) wall. In RN-based procedures, ablation was performed with a contact force of 10-40 g. The operator was blinded to the esophageal temperature (T(eso)). In the RN(2) group ablation power along the posterior LA wall was reduced to 20 W and ablation terminated at T(eso) of 41 degrees C. Endoscopy was carried out 2 days post-ablation. RESULTS: PVI was achieved in all patients. In the manual group no esophageal lesions, minimal lesions, or ulcerations were found in 15 of 25 (60%), 7 of 25 (28%), and 3 of 25 (12%) patients, respectively. All patients in the RN(1) group had an ulceration and one developed esophageal perforation. A covered stent was placed 14 days post-PVI and removed at day 81. In the RN(2) group, only a single minimal lesion was found. CONCLUSIONS: A high incidence of thermal esophageal injury including a perforation was noted following robotic PVI using 30 W along the posterior LA wall. During RN-based PVI procedures esophageal temperature monitoring is advocated. Reduction of ablation power to 20 W and termination of energy delivery at T(eso) of 41 degrees C significantly reduced the risk of esophageal injury.

Right ventricular rapid pacing in catheter ablation of atrial fibrillation: a novel application for cryoballoon pulmonary vein isolation.

BACKGROUND: Cryoballoon ablation (Arctic Front, Cryocath) represents a novel technology for pulmonary vein isolation (PVI). The initial phase of a freeze is crucial for cryolesion formation which is determined by local temperature depending on blood flow. We investigated the impact of right ventricular rapid pacing (RVRP) on temperature kinetics in patients (pts) with paroxysmal atrial fibrillation (PAF). METHODS AND RESULTS: Right ventricular rapid pacing was performed from the RV apex. Absolute minimal temperature (MT, degrees C), temperature slopes [time (s) to 80% MT; dT/dt), area under the curve (AUC) and arterial blood pressure (ABP, mmHg) were compared (group I: with RVRP vs. group II: without RVRP). RVRP (mean duration 55 +/- 7 s) was performed in 11 consecutive PAF pts (41 PVs, age 58 +/- 9 years, LA size 44 +/- 6 mm, normal ejection fraction). Only freezes with identical balloon positions were analyzed (11/41 PVs). RVRP (cycle length 333 +/- 3 ms) induced a significant drop in ABP (group I: 45 +/- 3 mmHg vs. group II: 100 +/- 18 mmHg, p < 0.001). MT was not different between group I and group II (-45.0 +/- 4.4 vs. -44.3 +/- 3.4 degrees C, p = 0.46), whereas slope (38.0 +/- 4.6 s vs. 51.6 +/- 14.4 s, p = 0.0034) and AUC (1090 +/- 4.6 vs. 1181 +/- 111.2, p = 0.02) was significantly changed. In one pt, a ventricular tachycardia was induced. PVI was achieved in 41/41 PVs. CONCLUSION: Right ventricular rapid pacing significantly accelerates cryoballoon cooling during the initial phase of a freeze possibly suggesting improved cryolesions.

Pulmonary vein isolation after left-sided pneumonectomy: technically challenging but feasible and instructive.

We present a technically challenging case of pulmonary vein isolation (PVI) after complete left-sided pneumonectomy, resulting in uncommon cardiac rotation. Wide area circumferential PVI after pneumonectomy is technically challenging but feasible in experienced centres. Correct identification of the PV ostia is crucial before ablation.

The 'single big cryoballoon' technique for acute pulmonary vein isolation in patients with paroxysmal atrial fibrillation: a prospective observational single centre study.

AIMS: Cryothermal energy (CTE) ablation via a balloon catheter (Arctic Front, Cryocath) represents a novel technology for pulmonary vein isolation (PVI). However, balloon-based PVI approaches are associated with phrenic nerve palsy (PNP). We investigated whether 'single big cryoballoon'-deployed CTE lesions can (i) achieve acute electrical PVI without left atrium (LA) imaging and (ii) avoid PNP in patients with paroxysmal atrial fibrillation (PAF). METHODS AND RESULTS: After double transseptal punctures, one Lasso catheter and a big 28 mm cryoballoon catheter using a steerable sheath were inserted into the LA. PV angiography and ostial Lasso recordings from all PVs were obtained. Selective PV angiography was used to evaluate balloon to LA-PV junction contact. CTE ablation lasted 300 s, and the PN was paced during freezing at right-sided PVs. Twenty-seven patients (19 males, mean age: 56 +/- 9 years, LA size: 42 +/- 5 mm) with PAF (mean duration: 6.6 +/- 5.7 years) were included. PVI was achieved in 97/99 PVs (98%). Median (Q(1); Q(3)) procedural, balloon, and fluoroscopy times were 220 min (190; 245), 130 min (90; 170), and 50 min (42; 69), respectively. Three transient PNP occurred after distal PV ablations. No PV stenosis occurred. Total median (Q(1); Q(3)) follow-up time was 271 days (147; 356), and 19 of 27 patients (70%) remained in sinus rhythm (3-month blanking period). CONCLUSION: Using the single big cryoballoon technique, almost all PVs (98%) could be electrically isolated without LA imaging and may reduce the incidence of PNP as long as distal ablation inside the septal PVs is avoided.

Magnetic navigation and catheter ablation of right atrial ectopic tachycardia in the presence of a hemi-azygos continuation: a magnetic navigation case using 3D electroanatomical mapping.

INTRODUCTION: We report on a 63-year-old female patient in whom an electrophysiologic study discovered a hemi-azygos continuation. Using the magnetic navigation system, remote-controlled ablation was performed in conjunction with the 3D electroanatomical mapping system. METHODS AND RESULTS: Failing the attempt to advance a diagnostic catheter from the femoral vein, a diagnostic catheter was advanced via the left subclavian vein into the coronary sinus. The soft magnetic catheter was positioned in the right atrium via the hemi-azygos vein, and 3D mapping demonstrated an ectopic atrial tachycardia. Successful ablation was performed entirely remote controlled. Fluoroscopy time was only 7.1 minutes, of which 45 seconds were required during remote navigation. CONCLUSION: Remote-controlled catheter ablation using magnetic navigation in conjunction with the electroanatomical mapping system proved to be a valuable tool to perform successful ablation in the presence of a hemi-azygos continuation.

Remote navigation systems in electrophysiology.

Today, atrial fibrillation (AF) is the dominant indication for catheter ablation in big electrophysiologists (EP) centres. AF ablation strategies are complex and technically challenging. Therefore, it would be desirable that technical innovations pursue the goal to improve catheter stability to increase the procedural success and most importantly to increase safety by helping to avoid serious complications. The most promising technical innovation aiming at the aforementioned goals is remote catheter navigation and ablation. To date, two different systems, the NIOBE magnetic navigation system (MNS, Stereotaxis, USA) and the Sensei robotic navigation system (RNS, Hansen Medical, USA), are commercially available. The following review will introduce the basic principles of the systems, will give an insight into the merits and demerits of remote navigation, and will further focus on the initial clinical experience at our centre with focus on pulmonary vein isolation (PVI) procedures.