The influence of epicardial and endocardial use of cryoenergy on the completeness of lesions in surgical ablation of atrial fibrillation.

INTRODUCTION: Cryoenergy is the most commonly used method of lesion formation in patients who have undergone surgical ablation of atrial fibrillation. Despite frequent use, the clinical effect of cryoenergy in endocardial and epicardial approaches is unknown. AIM: To compare the effect of various cryoenergy applications on the postoperative incidence of sinus rhythm and completeness of lesions performed. MATERIAL AND METHODS: A total of 55 patients underwent concomitant atrial fibrillation surgical ablation using cryoenergy under various conditions: epicardially during cardiac arrest, epicardially on beating heart, and endocardially. In the postoperative period, patients were invited to attend an electrophysiological examination to assess the completeness of surgical ablation lesions and, if necessary, to complete catheter ablation. RESULTS: Twenty-four patients underwent epicardial ablation on the arrested heart (group 1), 12 patients underwent epicardial ablation on the beating heart (group 2), and 19 patients underwent endocardial ablation (group 3). In the electrophysiological examination, sinus rhythm was present in 71% vs. 83% vs. 89% of patients, respectively. The completeness of pulmonary vein isolation was confirmed in 31% vs. 25% vs. 95% of patients, complete box lesions in 15% vs. 0% vs. 79% of patients, respectively. CONCLUSIONS: Despite the similar clinical effect of surgical ablation in all three approaches, the morphologically most effective use of cryoenergy is endocardial ablation. This approach has a very good result. Our findings further support the endocardial use of cryoenergy during surgical ablation of atrial fibrillation.

Nurse-performed venous sheath removal in patients undergoing radiofrequency catheter ablation for atrial fibrillation: a randomised study.

BACKGROUND: Catheter ablation procedures have recently become a widely accepted method for treating cardiac arrhythmias, and referrals for these procedures have been steadily increasing. As a result, it is now common that sheath removal is handled as a nursing procedure. Regardless of who performs the sheath removal, it is important to extract ablation sheaths without any early or late complications. OBJECTIVE: The aim of this randomised study was to determine the safety of sheath extraction after heparin reversal with low-dose protamine sulfate in patients undergoing radiofrequency catheter ablation for atrial fibrillation and whether these sheaths can be safely removed by nurses. METHODS: Eighty-one patients were randomly assigned to either receiving protamine to reverse heparin after an ablation ( n=40) or to the standard protocol without heparin reversal ( n=41). Nurse-led sheath removal was done in the cath lab (protamine group) or on the ward (standard group) as soon as activated partial thromboplastin time dropped below 60 s. All adverse events, groin compression time, immobilisation time and procedure characteristics were recorded. RESULTS: The manual compression time for the standard group was significantly longer than for the protamine group (15.9 ± 2.5 vs. 21.9 ± 3.1 minutes, P<0.001) as well as the total immobilisation time (13.2 ± 2.4 vs. 20.3 ± 3.8 hours, P=0.01). Minor groin haematomas occurred less frequently in the protamine group (4 vs. 12, P=0.02) and the haematomas tended to be smaller (4.1 ± 2.1 vs. 5.2 ± 2.5 cm, P=0.09). No serious adverse events were observed when the femoral sheaths were extracted by specially trained staff nurses. CONCLUSION: Fewer and milder complications and shorter immobilisation times were reported with protamine reversal compared to the conventional method. Staff nurses can safely remove femoral venous sheaths after a radiofrequency ablation for atrial fibrillation.

Clinical outcomes of radiofrequency catheter ablation of atrial fibrillation in octogenarians-10-year experience of a one high-volume center.

BACKGROUND: Prevalence of atrial fibrillation (AF) increases with age. Radiofrequency catheter ablation (RFCA) is an established treatment option superior to antiarrhythmics (AAs). In this study, we investigated safety and efficacy of RFCA of AF in octogenarians. METHODS: From our database, we extracted procedural and follow-up data for patients ≥ 80 years with symptomatic AF undergoing RFCA and compared this population to RFCA patients ≤ 50 years. All patients underwent pulmonary vein isolation (PVI) supplemented by linear lesions in PVI-nonresponders. Arrhythmia-free survival was assessed using seven day Holter every three months post procedure. All patients completed their 12 months follow-up. RESULTS: Fifty patients aged ≥ 80 years (80.5 ± 1.6 years) were compared to 259 patients aged ≤ 50 years (43.5 ± 5.5 years). The RFCA complication rate did not vary between groups. No differences in procedural characteristics were seen after being analyzed by type of AF. Among patients with paroxysmal AF, 71.4% octogenarian vs. 84.7% young patients was free of any arrhythmia, without AAs, after single procedure. For non-paroxysmal AF, arrhythmia-free survival without AAs, was considerably lower (58.6% octogenarians vs. 81.2% younger patients, P = 0.023). If AAs were used, arrhythmia-free survival for paroxysmal AF increased to 90.5% and 92.1% in octogenarians and younger patients, respectively; and in non-paroxysmal AF it increased to 79.3% vs. 88.4%. CONCLUSIONS: RFCA is a safe and effective strategy to achieve normal sinus rhythm in a highly selected group of octogenarians. Paroxysmal AF ablation in octogenarians has similar clinical effectiveness as that seen in much younger patients. Non-paroxysmal AF ablation has lower, but still reasonable clinical effectiveness.

Correlates of Arrhythmia Recurrence After Hybrid Epi- and Endocardial Radiofrequency Ablation for Persistent Atrial Fibrillation.

BACKGROUND: Long-term efficacy of catheter-based treatment of persistent atrial fibrillation is unsatisfactory. Minimally invasive surgical ablation techniques have been developed recently, but their efficacy has never been systematically tested. METHODS AND RESULTS: Seventy patients (median age, 63.5 years) with persistent atrial fibrillation underwent epicardial thoracoscopic radiofrequency pulmonary vein isolation, linear ablation, Marshal ligament disruption, and exclusion of the left atrial appendage. The procedure was followed by electroanatomic mapping and ablation (EAM) 2 to 3 months later. Only 76% of patients were in normal sinus rhythm at the beginning of EAM. All 4 pulmonary veins and the left atrium posterior wall were found isolated in 69% and 23% of patients, respectively. Arrhythmia-free survival off antiarrhythmic drugs 12 months after EAM was 77%. Using previously ineffective antiarrhythmic drugs and reablation procedures, arrhythmia free-survival increased to 97% during follow-up (mean, 936±432 days; range, 346-1509 days). The majority of arrhythmia recurrences occurred during the first 12 months after EAM. In a multivariable-adjusted estimates, left atrium volume >165 mL, absent normal sinus rhythm at admission for EAM, and inducibility of any sustained tachyarrhythmia at the end of EAM procedure were identified as independent correlates of atrial fibrillation recurrence. CONCLUSIONS: Our report demonstrated that the majority of patients after epicardial ablation, using bipolar radiofrequency instruments, required endocardial catheter ablation to complete the linear ablation lesions and a significant proportion of patients required spot-ablations to complete electric pulmonary vein isolation. Noninducibility of any arrhythmia after a staged hybrid procedure seemed to be the strongest correlate of long-term arrhythmia-free survival. CLINICAL TRIAL REGISTRATION: URL: www.ablace.cz. Unique identifier: cz-060520121617.

[Closure of the left atrial appendage by means of the AtriClip System]. / Uzáver ouska levé síne systémem AtriClip.

INTRODUCTION: Atrial fibrillation (AFib) is related to a high risk of stroke. The main role in etiopathogenesis is played by the left atrial appendage (LAA). As many as 95 % of thrombi in nonvalvular atrial fibrillation are located in the appendage. Prevention of stroke then consists in permanent anticoagulation which, however, has its limits and risks. An alternative method is the left atrial appendage occlusion. In our report, we would like to present a new possibility of the closure using the epicardial system AtriClip (AtriCure). METHODOLOGY: In the period beginning in July 2012 - September 2015 we performed LAA closure in 101 patients. A mean age of 65 ± 6 years, 47 women, CHA2DS2 VASc (Ø) 2.47 (0-6). Monitoring 1 837 (Ø 18.5) months. A concomitant procedure was performed in 37 patients, endoscopic MAZE plus clip in 57 patients, and 7 patients underwent stand-alone implantation of the clip. The clip was implanted from full sternotomy, minitoracotomy or through thoracoscopy. Clip loading, residual recess and endoleak were assessed through endoscopic ultrasound according to the Cleveland criteria. RESULTS: The perioperative success rate of loading reached 98 %. The clip was loaded with a neck greater than 1 cm in 2 patients. No migration of the clip occurred, no endoleak was detected and no thrombus at the appendage base was detected. One case of periprocedural stroke was recorded. Within follow-up monitoring TIA occurred in 4 patients and no stroke was recorded. CONCLUSION: Epicardial LAA occlusion using the AtriClip system is a safe and reproducible method of LAA occlusion and an important alternative in the prevention of stroke.Key words: atrial fibrillation - occlusion of left atrial appendage - stroke.

Sequential Hybrid CryoMaze Ablation versus Surgical CryoMaze Alone for the Treatment of Atrial Fibrillation (SurHyb): study protocol for a randomized controlled trial.

BACKGROUND: Atrial fibrillation is common in patients with structural heart disease who are undergoing cardiac surgery. Surgical CryoMaze has been shown to be an effective treatment in several trials, but success rates have varied considerably, between 47-95 %. The sequential hybrid approach, combining surgical CryoMaze followed by radiofrequency catheter ablation, can achieve high freedom from atrial arrhythmias, even when rigorous methods to detect arrhythmias after the procedure are used. However, data from randomized trials comparing hybrid ablations to surgical ablations alone are lacking. METHODS/DESIGN: The SurHyb study is a prospective, multicenter, randomized study. Patients with persistent or long-standing persistent atrial fibrillation will be randomized to either surgical CryoMaze alone or surgical CryoMaze followed by catheter ablation 3 months post-surgery. The primary outcome measure is arrhythmia-free survival without class I or III antiarrhythmic drugs, which will be evaluated using 7-day ECG Holter monitoring at 24 months. A total of 260 patients will be investigated from three medical centers in the Czech Republic to obtain the relevant information. DISCUSSION: This is the first randomized study that compares surgical CryoMaze alone with the staged hybrid surgical CryoMaze followed by catheter ablation in patients with persistent or long-standing persistent atrial fibrillation. These results will contribute to the optimization of the treatment for these patients. TRIAL REGISTRATION: Czech Clinical Trials Registry, cz-301020151253 . Registered on 30 October 2015.

Sequential Hybrid Surgical CryoMaze and Transvenous Catheter Ablation of Atrial Fibrillation.

BACKGROUND: The aim of the study was to evaluate whether the sequential hybrid approach combining surgical CryoMaze followed by the radiofrequency (RF) catheter ablation can improve freedom from atrial arrhythmias. METHODS: Thirty-five patients with persistent atrial fibrillation underwent a CryoMaze procedure in conjunction with cardiac surgery for structural heart disease. Three months after surgery, all patients underwent a 7-day electrocardiogram Holter followed by an electrophysiological study and mapping of the left and right atria. All pulmonary veins were reisolated and all ablation lines were completed, if necessary, using RF energy. Patients were followed-up at 3 months, 6 months, and 12 months after the catheter ablation. RESULTS: Before the mapping study and RF ablation, nine patients (26%) had ongoing atrial fibrillation or atrial tachycardia, 10 patients (28%) had paroxysmal atrial tachyarrhythmia, and 16 patients (46%) had sinus rhythm on the 7-day Holter monitoring. During the electrophysiological procedure, complete cryoablation lines around the left pulmonary veins were found in 29 patients (83%), around the right pulmonary veins in 25 patients (71%), between the superior veins in 20 patients (57%), between the inferior veins in 27 patients (77%), across the mitral isthmus in 12 patients (34%), and across the cavotricuspid isthmus in one patient (3%). Arrhythmia-free survival rate of antiarrhythmic drugs after reisolation of the veins and completion of the lines was 86% at 12 months. CONCLUSION: Ablation lines created using surgical CryoMaze are often incomplete. Sequential surgical CryoMaze procedures followed by catheter ablation significantly increase freedom from arrhythmia in patients with persistent atrial fibrillation.

Thoracoscopic Occlusion of the Left Atrial Appendage.

OBJECTIVE: Left atrial appendage (LAA) plays a crucial role in the etiopathogenesis and the prevention of the stroke in patients with nonvalvular atrial fibrillation (AF). This paper presents our first experience with thoracoscopic LAA occlusion using an external clip. METHODS: We performed a total of 30 LAA occlusions with the AtriClip from left thoracoscopy approach during the period from July 2012 to July 2013. AtriClip was implanted during the bilateral thoracoscopic radiofrequency (RF) as part of left atrial ablation procedure. RESULTS: Among the 30 procedures, AtriClip was once periprocedurally partially positioned. In the remaining procedures, the implantation was successful without complications. Of the 30 patients, 29 underwent transesophageal echocardiography and computer tomography examination at 3 months after the procedure. Apart from the patient with the partial clip placement, a residual pouch of 18 mm was detected in another patient. In the remaining group (28/30 patients, 93%), the exclusion was complete. No migration or any other clip implantation-related complications occurred during the follow-up. None of the patients experienced an embolization event. CONCLUSIONS: Endoscopic AtriClip implantation appears to be a reproducible and safe method of LAA occlusion, with a minimal risk and a high efficiency. In our opinion, the AtriClip implantation is a reasonable part of thoracoscopic AF treatment and should be considered as an alternative tool for stroke risk reduction in patients with AF.

Sequential hybrid procedure for persistent atrial fibrillation.

BACKGROUND: Catheter ablation of persistent atrial fibrillation yields an unsatisfactorily high number of failures. The hybrid approach has recently emerged as a technique that overcomes the limitations of both surgical and catheter procedures alone. METHODS AND RESULTS: We investigated the sequential (staged) hybrid method, which consists of a surgical thoracoscopic radiofrequency ablation procedure followed by radiofrequency catheter ablation 6 to 8 weeks later using the CARTO 3 mapping system. Fifty consecutive patients (mean age 62±7 years, 32 males) with long-standing persistent atrial fibrillation (41±34 months) and a dilated left atrium (>45 mm) were included and prospectively followed in an unblinded registry. During the electrophysiological part of the study, all 4 pulmonary veins were found to be isolated in 36 (72%) patients and a complete box-lesion was confirmed in 14 (28%) patients. All gaps were successfully re-ablated. Twelve months after the completed hybrid ablation, 47 patients (94%) were in normal sinus rhythm (4 patients with paroxysmal atrial fibrillation required propafenone and 1 patient underwent a redo catheter procedure). The majority of arrhythmias recurred during the first 3 months. Beyond 12 months, there were no arrhythmia recurrences detected. The surgical part of the procedure was complicated by 7 (13.7%) major complications, while no serious adverse events were recorded during the radiofrequency catheter part of the procedure. CONCLUSIONS: The staged hybrid epicardial-endocardial treatment of long-standing persistent atrial fibrillation seems to be extremely effective in maintenance of normal sinus rhythm compared to radiofrequency catheter or surgical ablation alone. Epicardial ablation alone cannot guarantee durable transmural lesions. CLINICAL TRIAL REGISTRATION: URL: www.ablace.cz Unique identifier: cz-060520121617.

Catheter Ablation of Atrial Fibrillation Using Zero-Fluoroscopy Technique: A Randomized Trial.

BACKGROUND: Recent advances in 3D mapping systems, such as simultaneous visualization of multiple catheters and contact force measurement, have allowed a significant reduction in fluoroscopic times during radiofrequency (RF) ablation (RFA) procedures. The objective was to investigate whether RFA of paroxysmal atrial fibrillation (PAF) using the CARTO 3 system (Biosense Webster, Diamond Bar, CA, USA) and intracardiac echocardiography (ICE) can be performed safely without fluoroscopy. METHODS AND RESULTS: Eighty patients with PAF were randomized in a 1:1 ratio to undergo either fluoroscopically guided pulmonary vein isolation (PVI) (X+) or PVI without fluoroscopy (X-). In the X- fluoroscopy group, catheter placement, transseptal puncture, left atrial geometry reconstruction, and PVI were accomplished solely using ICE imaging and CARTO mapping. The total procedure duration and RF application time in both the X- and X+ groups were comparable (92.5 ± 22.9 minutes vs 99.9 ± 15.9 minutes, P = 0.11 and 1785 ± 548 seconds vs 1755 ± 450 seconds, P = 0.79, respectively). Zero fluoroscopic time was achieved in all patients in the X- group with the exception of one patient, where 8 seconds of fluoroscopy was needed to assess proper position of the guide-wire in the femoral vein. No serious procedure-related complications were recorded and no differences in arrhythmia-free survival at 12 months were found between the groups. CONCLUSION: RFA using ICE imaging and the CARTO 3 mapping system with contact force measurement is capable of eliminating fluoroscopy in patients undergoing PVI. Exclusion of fluoroscopic imaging does not seem to compromise patient safety and does not affect overall procedure duration, RF application time, or mid-term efficacy.

Two-staged hybrid treatment of persistent atrial fibrillation: short-term single-centre results.

OBJECTIVES: The treatment of persistent and long-standing persistent atrial fibrillation (AF) has unsatisfactory results using both medical therapy and/or catheter ablation, where incomplete ablation lines remain a significant problem. This study evaluates the feasibility, efficacy and safety of the sequential, two-staged hybrid treatment combining thoracoscopic surgical and transvenous catheter AF ablation. METHODS: Thirty patients with persistent and long-standing persistent AF underwent surgical thoracoscopic radiofrequency (RF) ablation procedure using a predefined protocol (pulmonary veins isolation, box lesion, isthmus line lesion, dissection of the ligament of Marshall, left atrial appendage exclusion with an epicardial clip and ganglionated plexi ablation) followed by diagnostic catheterization and RF ablation 3 months later. In this session, electrical mapping of the left atrium was performed and any incomplete isolation lines were completed. Mitral and cavotricuspid isthmus ablation lines were performed during this session as well. RESULTS: The preoperative mean duration time of AF was 33 ± 27 months with 17% patients with persistent and 83% patients with long-standing persistent AF. The mean size of the left atrium was 48 ± 5 mm. The complete surgical ablation protocol was achieved in 97% of patients, with no death, and no early stroke or pacemaker implantation in the early postoperative period. In 63% of patients, the left atrial appendage was excluded with an epicardial clip. An endocardial touch-up for achievement of bidirectional block of pulmonary veins was necessary in 10 patients (33%) and on the box, (roof and floor) lesions in 20 patients (67%). Freedom from atrial fibrillation was 77% after surgical ablation and 93% after the completed hybrid procedure. CONCLUSIONS: The sequential, two-staged hybrid strategy (surgical thoracoscopic followed by catheter ablation) is feasible and safe with a high post-procedural success and seems to represent the optimal treatment with low risk load and potentially long-term benefit for patients with a persistent and long-standing persistent form atrial fibrillation.

Catheter ablation for paroxysmal atrial fibrillation: a randomized comparison between multielectrode catheter and point-by-point ablation.

INTRODUCTION: Catheter ablation for paroxysmal atrial fibrillation is widely used for patients with drug-refractory paroxysms of arrhythmia. Recently, novel technologies have been introduced to the market that aim to simplify and shorten the procedure. AIM: To compare the clinical outcome of pulmonary vein (PV) isolation using a multipolar circular ablation catheter (PVAC group), with point-by-point PV isolation using an irrigated-tip ablation catheter and the CARTO mapping system (CARTO group; CARTO, Biosense Webster, Diamond Bar, CA, USA). METHODS: Patients with documented PAF were randomized to undergo PV isolation using PVAC or CARTO. Atrial fibrillation (AF) recurrences were documented by serial 7-day Holter monitoring. RESULTS: One hundred and two patients (mean age 58 ± 11 years, 68 men) were included in the study. The patients had comparable baseline clinical characteristics, including left atrial dimensions and left ventricular ejection fraction, in both study arms (PVAC: n = 51 and CARTO: n = 51). Total procedural and fluoroscopic times were significantly shorter in the PVAC group (107 ± 31 minutes vs 208 ± 46 minutes, P < 0.0001 and 16 ± 5 minutes vs 28 ± 8 minutes, P < 0.0001, respectively). The AF recurrence was documented in 23% and 29% of patients in the PVAC and CARTO groups, respectively (P = 0.8), during the mean follow-up of 200 ± 13 days. No serious complications were noted in both study groups. CONCLUSIONS: Clinical success rates of PV isolation are similar when using multipolar circular PV ablation catheter and point-by-point ablation with a three-dimensional (3D) navigation system in patients with PAF, and results in shorter procedural and fluoroscopic times with a comparable safety profile.

Mitral isthmus conduction block: intriguing result of radiofrequency catheter ablation for a left concealed accessory pathway.

We report on our experience with complete mitral isthmus conduction block achieved inadvertently during radiofrequency (RF) catheter ablation for a left lateral concealed accessory pathway (AP) mimicking concentric retrograde activation. This rare condition should be acknowledged to avoid misdiagnosis of another concomitant AP and to avoid RF applications in inappropriate areas.