Buelent Koektuerk

Remote-controlled magnetic pulmonary vein isolation using a new irrigated-tip catheter in patients with atrial fibrillation.

Background—Lack of an irrigated-tip magnetic catheter has limited the role of remote-controlled magnetic navigation (Niobe II, Stereotaxis) for catheter ablation of atrial fibrillation (AF). Methods and Results—A novel 3.5-mm-tip irrigated magnetic catheter (group 1, Thermocool Navistar RMT, Biosense Webster) was used for 3D left atrial reconstruction (CARTO RMT) and remote-controlled magnetic pulmonary vein isolation. A redesigned catheter was used in group 2. The primary end point was wide area circumferential pulmonary vein isolation confirmed by spiral catheter recording during ablation; secondary end points included procedural data, complications, and AF recurrence. Fifty-six consecutive patients [group 1: 28 patients, 22 males, age 64 (38 to 78) years, left atrium: 47 (34 to 52) mm; paroxysmal AF: n=21, persistent AF: n=7; group 2: 28 patients, 20 males, age 60 (24 to 78) years, left atrium: 40 (35 to 53) mm; paroxysmal AF: n=18, persistent AF: n=10] were included. The primary end point was achieved in a total of 52 of 56 (93%) patients. Median procedure duration was 315 (125 to 550) minutes (group 1: 370 [230 to 550] minutes; group 2: 243 [125 to 450] minutes). Median fluoroscopy exposure to the investigator was reduced by 31%. Tip charring in 17 of 28 (61%) and complications in 3 of 28 (11%) patients in group 1 resulted in a catheter redesign. Sinus rhythm was maintained by 35 of 50 (70%) patients during a median follow-up period of 545 (100 to 683) days. Conclusions—Remote-controlled magnetic AF ablation with real-time verification of pulmonary vein isolation is feasible with a comparable success rate to manual ablation. Safety improved after a redesign of the catheter.

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.

Long-term clinical outcome following pulmonary vein isolation with high-intensity focused ultrasound balloon catheters in patients with paroxysmal atrial fibrillation

AIMS High-intensity focused ultrasound (HIFU) applied via a balloon catheter is a novel technology for pulmonary vein isolation (PVI) in patients with paroxysmal atrial fibrillation (PAF). The long-term success rate is unknown. METHODS AND RESULTS Thirty-two patients (22 male, age 60 +/- 9 years) with a long history [5 (4;9) years] of drug refractory [3 +/- 1 anti-arrhythmic drugs (AADs)], symptomatic PAF were included into the analysis. Pulmonary vein isolation was performed using the first- and second-generation HIFU balloon catheters (ProRhythm, Ronkonkoma, NY, USA). Follow-up (F/U) included regular telephonic interviews, trans-telephonic Holter ECG, and event recording. Recurrence was defined as a documented or symptomatic AF episode >30 s without a blanking period. In total 101/116 targeted PVs (87%) were acutely isolated exclusively using HIFU. During a median F/U of 1400 (930;1568) days, 18 patients (56%) were free of AF without AAD after a single HIFU procedure. In nine patients with AF recurrence, 20 PVs exhibited electrical reconduction and re-isolation was performed using irrigated radiofrequency current (RFC) ablation. CONCLUSION Patients treated with the first- and second-generation HIFU balloon catheters due to symptomatic PAF show long-term success rates similar to RFC-based PVI procedures. The major determinant of AF recurrence after HIFU treatment seems to be reconduction of previously isolated PVs. However, the favourable effectiveness is offset by the severe complications reported following HIFU treatment. This led to a halt of its clinical use.

Catheter ablation of right ventricular outflow tract tachycardia: a simplified remote-controlled approach

AIMS Manual mapping and ablation of right ventricular outflow tract (RVOT) tachycardia may be associated with cardiac perforation and complicated by mechanically induced ventricular extrasystoles (VESs). The aim of this study was to assess remote-controlled magnetic (RCM) mapping and ablation of RVOT ventricular tachycardia (VT)/VES utilizing a soft magnetic catheter. METHODS AND RESULTS Mapping and ablation of RVOT VT/VES were performed using the magnetic navigation system (MNS, Niobe II, Stereotaxis, St Louis, MO) in conjunction with a cardiodrive motor unit (Stereotaxis). A soft magnetic catheter (Celsius RMT, 4 mm solid tip, Biosense Webster, Diamond Bar, CA) was navigated to the RVOT using a sequence of pre-installed magnetic vectors. The primary endpoint was defined as successful RCM VT/VES ablation. Other parameters observed included RCM RVOT accessibility, mapping-induced mechanical VES, fluoroscopy time, complications, and arrhythmia recurrence. Thirteen consecutive patients (mean age: 50 ± 14 years; 10 females, 6 RVOT VT) underwent RCM mapping and ablation. The RVOT was reached in all patients utilizing solely the MNS. Successful RCM RVOT ablation was achieved in {12 of 13} (92.3%) patients. Mean procedure and fluoroscopy times were 116.5 ± 48.9 and 7.5 ± 4.3 min, respectively. Catheter-induced VES during RVOT mapping were observed in {1 in 13} patients (7.7%, three VES). No complications occurred. During a mean follow-up of 252 ± 211 days, clinical arrhythmia recurrence was observed in {1 in 13} (7.7%) patients. CONCLUSIONS Automatic RCM RVOT access is feasible, while RVOT mapping and ablation appear to be safe, fast, and effective. The soft magnetic catheter rarely induces mechanical VES.

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.

Role of diabetes in heart rhythm disorders

The incidence of diabetes mellitus (DM) is increasing rapidly. DM is the leading cause of cardiovascular diseases, which can lead to varied cardiovascular complications by aggravated atherosclerosis in large arteries and coronary atherosclerosis, thereby grows the risk for macro and microangiopathy such as myocardial infarction, stroke, limb loss and retinopathy. Moreover diabetes is one of the strongest and independent risk factor for cardiovascular morbidity and mortality, which is associated frequently with rhythm disorders such as atrial fibrillation (AF) and ventricular arrhythmias (VA). The present article provides a concise overview of the association between DM and rhythm disorders such as AF and VA with underlying pathophysiological mechanisms.

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.