[Perioperative management for cardiovascular implantable electronic devices]. / Perioperatives Management bei der Versorgung mit aktiven Rhythmusimplantaten.

Cardiovascular implantable electronic devices (CIED) are an important part of modern cardiology and careful perioperative planning of these procedures is necessary. All information relevant to the indication, the procedure, and the education of the patient must be available prior to surgery. This provides the basis for appropriate device selection. Preoperative antibiotic prophylaxis and perioperative anticoagulation management are essential to prevent infection. After surgery, postoperative monitoring, telemetric control, and device-based diagnostics are required before discharge. These processes need to be adapted to the increasing trend towards outpatient care. This review summarises perioperative management based on practical considerations.

[Atypical atrial fibrillation : Diagnostics and therapy]. / Atypisches Vorhofflattern : Diagnostik und Therapie.

In contrast to typical atrial flutter, atypical atrial flutter is a heterogeneous group of right and left atrial macro- or localized reentry tachycardias whose critical component for maintaining tachycardia is not the cavotricuspid isthmus. Atypical atrial flutter occurs more frequently after previous catheter ablation and after cardiac surgery. The intraprocedural success rate during ablation is high, although the recurrence rate depends on structural changes in the atria as well as the underlying mechanism. This article provides an overview of the mechanisms as well as mapping and ablation strategies of the most common forms of right and left atrial atypical atrial flutter. This article is part of the "EP Basics" series for targeted continuing education in invasive electrophysiology. Basics, clinic and therapy of atypical atrial flutter are presented with focus on clinically relevant aspects. Procedures and findings of invasive electrophysiological diagnostics and ablation treatment are the focus of this article.

Acute and long-term success of left atrial anterior line and mitral isthmus line ablation in patients after mitral valve surgery.

BACKGROUND: Perimitral flutter and atrial fibrillation may occur in patients with prior surgical mitral valve (MV) repair or replacement and can be challenging for percutaneous catheter ablation. This study sought to determine the feasibility, acute success and durability of catheter ablation of atrial fibrillation or atrial tachycardia by way of a mitral isthmus line (MIL) or an anterior line (AL). METHODS: A total of 81 patients (49 males, mean age 62±11 years) with prior MV replacement (n = 30) or reconstruction (n = 51) underwent creation of a MIL (34) and/or an AL (72). RESULTS: Acute bidirectional block of the MIL was successfully achieved in 24/34 cases and of the AL in 64/72 patients. Patients of the control group without prior MV surgery were matched 1:1 with the valve group. In the AL control subgroup, acute bidirectional block was achieved in 65/72 patients. Acute blockage in the MIL control subgroup could be achieved in 31/34 patients. The MIL valve subgroup showed the worst results in terms of durability, whereas a similar trend emerged in the control group and the AL valve subgroup (probability of failure in MIL valve subgroup 2.224 vs. MIL control subgroup 0.605 [Hazard Ratio (HR) = 0.27, 95% confidence interval (CI), 0.11-0.65), P = .004]; probability of failure in AL valve subgroup 0.844 vs. AL control subgroup 1.03 [HR = 1.22 (95% CI, 0.66-2.26), P = .523]). CONCLUSIONS: Percutaneous creation of MIL and AL is feasible and safe in patients with prior MV replacement/repair and associated with moderate acute and long-term success rates to achieve bidirectional block.

Impact of a time-to-effect-guided ablation protocol in cryoballoon ablation on the durability of pulmonary vein isolation.

BACKGROUND: Cryoballoon (CB)-based pulmonary vein isolation (PVI) has proven to be as effective as radiofrequency-based ablation. Different ablation protocols took the individual time-to-isolation (TTI) into account aiming at shorter but equally or even more effective freeze cycles. The current study sought to assess the impact of the TTI on PVI durability in patients undergoing a repeat procedure for recurrence of atrial tachyarrhythmia (ATA). METHODS AND RESULTS: In 205 patients with ATA recurrence after previous CB-based PVI, a total of 806 pulmonary veins (PVs) were identified. A total of 126 out of 806 PVs (16%) were previously treated with a TTI-guided ablation (Protocol #1; TTI + 120 s), in 92/806 (11%) PVs TTI was only monitored (m) but fixed freeze cycles were applied (Protocol #2; mTTI) and in 588/806 (73%) a fixed freeze cycle was applied without mTTI. There was no difference in the PV-reconduction rate between the groups (p = .23). The right inferior pulmonary vein (RIPV) showed overall significantly higher reconduction rates compared to the other PVs (RIPV-left inferior PV p < .003, -left superior PV p < .001, -right superior PV p < .013). Twenty-one patients (10%) were demonstrated to have only electrical reconduction of the RIPV, while all other PVs were still electrically isolated. CONCLUSIONS: The TTI-based CB ablation protocol did not show significant differences regarding PV-reconduction rates compared to the other ablation protocols.

Clinical outcomes of cryoballoon ablation for pulmonary vein isolation: Impact of intraprocedural heart rhythm.

BACKGROUND: The current study sought to assess the impact of the intraprocedural heart rhythm (sinus rhythm [SR] vs. atrial fibrillation [AF]) on acute procedural characteristics, durability of pulmonary vein isolation (PVI) and long-term clinical outcomes of cryoballoon (CB) ablation. METHODS: A total of 195 patients with symptomatic paroxysmal (n = 136) or persistent AF (n = 59) underwent CB-based PVI. Ablation procedures were either performed in SR (SR group; n = 147) or during AF (AF group; n = 48). Persistent AF was more frequent in the AF group than in the SR group (62% vs. 20%). All other patient baseline characteristics did not differ between the two groups. RESULTS: The nadir temperature during the CB applications was significantly lower in the AF group than in patients in the SR group (-49 [interquartile range, -44; -54]°C vs. -47 [-42; -52]°C, p = 0.002). Median procedure and fluoroscopy times as well as the rate of real-time recordings were not different between the two groups. Repeat ablation for the treatment of atrial arrhythmia recurrence was performed in 60 patients (SR: 44 [30%] patients; AF: 16 [33%] patients), with a trend towards a lower rate of pulmonary vein reconnections in the AF group (p = 0.07). There was no difference in 3-year arrhythmia-free survival (p = 0.8). CONCLUSIONS: Cryoballoon-based PVI during AF results in lower nadir balloon temperatures and a trend towards a higher durability of PVI as compared to procedures performed in SR. The rate of real-time PVI recordings was not affected by the intraprocedural heart rhythm.

Complications and mortality after catheter ablation of ventricular arrhythmias: risk in VT ablation (RIVA) score.

AIMS: Catheter ablation of ventricular arrhythmias (VA) has proven to be an effective therapeutic option for secondary arrhythmia prophylaxis. We sought to assess the procedural efficacy, safety and in-hospital mortality of a large patient cohort with and without structural heart disease undergoing VA ablation. METHODS: A total of 1417 patients (804 patients with structural heart disease) undergoing 1792 endo- and epicardial procedures were analyzed. Multivariable risk factor analysis for occurrence of major complications and intrahospital mortality was obtained and a score to allow preprocedural risk assessment for patients undergoing VA ablation procedures was established. RESULTS: Major complication occurred in 4.4% of all procedures and significantly more often in patients with structural heart disease than in structurally normal hearts (6.0 vs. 1.8%). The frequency of these periprocedural complications was significantly different between procedures with sole right ventricular and a combination of RV and LV access (0.5 vs. 3.1%). The most common complication was cardiac tamponade in 46 cases (3.0%). Intrahospital death was observed in 32 patients (1.8%). Logistic regression model revealed presence of ischemic heart disease, epicardial ablation, presence of oral anticoagulation or dual antiplatelet therapy as independent risk factors for the occurrence of complications or intrahospital death, while a history of previous heart surgery was an independent predictor with a decreased risk. Based on this analysis a risk score incorporating 5 standard variables was established to predict the occurrence of complications and intrahospital mortality. CONCLUSIONS: Safety of VA catheter ablation mainly relies on patient baseline characteristics and the type of access into the ventricles or epicardial space.

[Practical guide for safe and efficient cryoballoon ablation for atrial fibrillation : Practical procedure, tips and tricks]. / Leitfaden zur sicheren und effizienten Kryoballon-Vorhofflimmerablation : Praktisches Vorgehen, Tipps und Tricks.

In the current guidelines on treatment of atrial fibrillation, cryoballoon-based catheter ablation of atrial fibrillation is recommended in addition to radiofrequency ablation and has become established as a standard procedure in the clinical routine of many centers for index pulmonary vein isolation. A safe, simplified and often durable pulmonary vein isolation can be achieved by a systematic approach. This review article provides a practical guide for all steps of cryoballoon-based pulmonary vein isolation, including preprocedural preparation and postinterventional follow-up. Both cryoballoon systems currently available on the market are considered.

Quantification of Left Atrial Fibrosis in Patients After Pulmonary Vein Isolation Using the Second-Generation Cryoballoon.

Left atrial (LA) fibrosis is associated with a poor outcome after atrial fibrillation (AF) ablation. This study examined the extent of low-voltage areas in patients with recurrence of atrial tachyarrhythmia (ATA) after CB-based pulmonary vein isolation (PVI).Sixty patients (mean age 67 ± 10 years, n = 32 female; n = 34 paroxysmal AF) who received radiofrequency redo-procedure due to recurrence of ATA within 6 months after CB-based PVI were included. A point-by point 3D-map was performed, and low-voltage sites were delineated based on bipolar voltage < 0.5 mV. The extent of fibrosis was categorized as stage A (0-10% of the LA wall), stage B (10-30%), stage C (30-50%), and stage D (> 50%).The median area of LA low-voltage sites was 28.9 (9; 50.3) cm2, corresponding to 17.4 (6; 30.6) % of the LA wall surface. 17/60 (28.3%) patients were categorized as fibrosis stage A, 21/60 (35%) as stage B, 18/60 (30%) as stage C, and 4/60 (6.7%) as stage D. Patient age and LA diameter were associated with more pronounced LA fibrosis; the extent of LA fibrosis was significantly higher in patients with LA tachycardia (LAT) during redo-procedures (P < 0.01), and ablation of linear lesions was more often performed (P < 0.01).In patients after CB2-based PVI, expanded LA tissue fibrosis was associated with the occurrence of LAT and more extensive LA ablation during redo-procedures.

Absence of detectable effect of radiotherapy and chemotherapy for breast cancer on the presence of low voltage areas in patients receiving left atrial catheter ablation.

PURPOSE: Radiation and chemotherapy for breast cancer are known to cause side effects to the heart. However, it still remains unclear whether those therapies affect left atrium fibrosis. We sought to examine the effects of radiation and chemotherapy on the electroanatomic features of the left atrium (LA) in patients who received catheter ablation for LA arrhythmias and underwent radiation and/or chemotherapy prior to the procedure. METHODS AND RESULTS: We compared 38 patients who underwent catheter ablation for LA arrhythmias and had a previous diagnosis of breast cancer with 38 patients without breast cancer. LA low voltage zones (LVZ) were analysed during the electrophysiological (EP) study. The existence of LA LVZ did not differ significantly between both groups (71.1% vs. 76.3%, p = .602; 13.7cm2 (IQR 0;20.6cm2) vs. 7.0cm2 (IQR 1.6;21.1cm2), p = .690). Also scar distribution revealed no difference between both groups. However, an involvement of the anterior wall was common in both groups (65.8% vs. 73.7%, p = .454). Patients with breast cancer and persistent AF showed a trend towards greater LA scar areas 14.5% vs. 6.9%, p = .383) compared to the control group. Age and LA volume index were the only independent predictors for greater LA scarring. CONCLUSIONS: Thoracic irradiation and chemotherapy for breast cancer do not lead to an increase in LA scar area or a changed distribution of LA scarring. However, patient with breast cancer showed a tendency towards greater LA scar areas. Patient's age and LA volume index were identified as independent predictors for LA scar development.

Stroke and left atrial thrombi after cryoballoon ablation of atrial fibrillation: incidence and predictors. Results from a long-term follow-up.

Stroke after catheter ablation (CA) of atrial fibrillation (AF) is a potential complication with long term consequences. Aim of this study was to determine incidence and potential predictors of stroke and left atrial appendage (LAA) thrombi after AF ablation with cryo-energy. Two hundred nine consecutive patients with symptomatic drug refractory AF (65% male; 61 ± 11 yo, 69% paroxysmal AF, mean CHA2DS2-VASc score 2 ± 1.4) were enrolled between October 2012 until December 2015. Long term follow-up was performed with outpatient clinic visits at 6-month intervals. Incidence of stroke after CA was 1.4% (3/209 pts) at long term follow-up. Two out of 3 pts experienced stroke during the first 3 month after CA and one after 36 months. At long term follow-up LAA thrombi were found in two patients (1%) that were on therapeutic oral anticoagulation. Recurrence of AF was found in 4 out of 5 pts with stroke or LAA thrombi. Patients with stroke or LAA thrombi did not differed from those without in term of age, gender, CV risk factors, LA size and AF type. They differed only for EHRA score (2.4 vs 1.3, p = 0.01) before CA. At multivariate analysis after correction for age, gender, LA size, LVEF and AF type, only EHRA score (ß 1.92, 95% C.I. 1.3-35 p = 0.02), was an independent predictor of stroke/LAA thrombi. Incidence of stroke after cryoablation is low, with a relative higher prevalence during the first 3 months after CA. Prospective, multicenter long-term registries are needed for a better stroke risk stratification.

Left-lateral thoracotomy for catheter ablation of scar-related ventricular tachycardia in patients with inaccessible pericardial access.

OBJECTIVES: We aimed to describe the feasibility of a surgical left thoracotomy for catheter ablation of scar-related ventricular tachycardia (VT) in patients with inaccessible pericardial access. BACKGROUND: Pericardial adhesion due to prior cardiac surgery or previous epicardial ablation procedures limits epicardial access in patients with drug-refractory VT originated from the epicardium. METHODS: Six patients who underwent a surgical left lateral thoracotomy epicardial access for catheter ablation of VT after failed subxiphoid percutaneous epicardial access were reviewed. Patients' baseline characteristics and procedural characteristics including epicardial access, mapping, and ablation were described. Epicardial access was successfully obtained in all patients by a surgical left lateral thoracotomy. RESULTS: The reasons of pericardial adhesion were prior cardiac surgery (n = 3, 50%) and previous epicardial ablation procedures (n = 3, 50%). Epicardial mapping of the lateral and inferior left ventricle was acquired, and a total of 15 different VTs originated from those regions were abolished. Unless one patient with ST elevation myocardial infarction due to periprocedural occlusion of the posterior descending artery no further complications occurred. All patients were discharged 10.2 ± 4 days after the procedure. VT recurred in 1 patient (17%) and was controlled with oral amiodarone therapy during follow-up (median follow-up: 479 days). CONCLUSIONS: A surgical left lateral thoracotomy is feasible and safe for selected patients. This approach provides epicardial ablation in patients with VT located at the infero-lateral left ventricle and pericardial adhesions due to previous cardiac surgery or previous ablation procedures.

Epicardial access for VT ablation: analysis of two different puncture techniques, incidence of adhesions and complication management.

INTRODUCTION: Pericardial access for ablation of ventricular arrhythmias (VA) can be gained either by an anterior-oriented or inferior-oriented epicardial puncture under fluoroscopical guidance. We retrospectively sought to assess the safety of these two puncture techniques and the incidence of epicardial adhesions and introduce our algorithm for management of pericardial tamponade. METHODS AND RESULTS: In 211 patients (61.4 ± 15.6 years, 179 males; 84.8%) 271 epicardial ablation procedures of VA were performed using either an anterior- or inferior-oriented approach for epicardial access. Puncture-related complications were systematically analyzed. Furthermore, the incidence of adhesions was evaluated during first and repeated procedures. A total of 34/271 (12.5%) major complications occurred and 23/271 (8.5%) were directly related to epicardial puncture. The incidence of puncture-related major complications in the anterior and inferior group was 4/82 (4.9%) and 19/189 (10.1%), respectively. Pericardial tamponade was the most common major complication (15/271; 5.5%). Collateral damages of adjacent structures such as liver, colon, gastric vessels and coronary arteries occurred in 6/189 (3.2%) patients and only within the inferior epicardial access group. Adhesions were documented in 19/211 (9%) patients during the first procedure and in 47.1% if patients had 2 or more procedures involving epicardial access. CONCLUSION: Anterior-oriented epicardial puncture shows an observed association to a reduced incidence of pericardial tamponades and overall puncture-related complications in epicardial ablation of VA. In cases of repeated epicardial access adhesions increase significantly and may lead to ablation failure.

Atrial fibrillation ablation in patients with pulmonary lobectomy or pneumectomy: Procedural challenges and efficacy.

BACKGROUND: Catheter ablation of atrial fibrillation (AF) in patients with pulmonary lobectomy or pneumectomy is challenging due to anatomical alterations. After lung resection, electrically active pulmonary vein (PV) stumps remain and need to be localized for PV isolation (PVI). The present study aims to describe clinical challenges of PVI in patients with pulmonary lobectomy or pneumectomy. METHODS: We performed a retrospective study on 19 patients with previous pulmonary lobectomy or pneumectomy undergoing catheter ablation for AF in three German hospitals. RESULTS: Nineteen patients with paroxysmal, persistent, or longstanding-persistent AF and history of pulmonary lobectomy (n = 11) or pneumectomy (n = 8) were enrolled. Catheter ablation was performed as radiofrequency (RF) ablation using 3D mapping, robotic RF ablation, or by using balloon devices. Decent anatomical changes were observed in patients with lobectomy while cardiac rotation and mediastinal shifting was dominant in patients with pneumectomy. Visualization of all PVs including PV stumps by PV angiography was possible in 10 of 19 patients (52.6%). PV spikes were observed in all identified PV remnants. In nine patients (47.4%), at least one PV remnant could not be identified and electrical isolation was not performed. During 24 months follow-up, patients with incomplete PVI had a significantly shorter arrhythmia-free survival than patients with complete PVI (76.2% [95% Confidence interval (CI) 47.2-100.0%] vs 40.0% [95% CI 5.6-74.1%], P = .043). CONCLUSION: In patients with AF and previous lobectomy or pneumectomy, identification and isolation of all PVs are challenging but crucial for ablation success. Additional imaging techniques may be necessary to achieve complete PVI.

Outcome of cardiac tamponades in interventional electrophysiology.

AIMS: The aim of this study was to analyse tamponades following electrophysiological procedures regarding frequency and mortality in a high-volume centre and to identify independent predictors for severe tamponades. METHODS AND RESULTS: We performed a retrospective study on 34 982 consecutive patients undergoing diagnostic electrophysiological studies or catheter ablation of cardiac arrhythmias. The combined endpoint was defined as severe tamponade. Criteria for severe tamponade included surgical repair, repeat pericardiocentesis, cardiopulmonary resuscitation, intrahospital death or death during follow-up, and thrombo-embolic events or complications due to therapeutic management. Multivariate analysis was performed to identify independent predictors for severe tamponade. A total of 226 tamponades were identified. Overall frequency of tamponades was 0.6%. Procedures requiring epicardial approach had the highest rate of tamponades (9.4%). Twenty-nine patients with tamponade underwent surgery (12.8% of all tamponades and 21.4% of tamponades during epicardial procedures). Overall tamponade-related mortality was 0.03% (9 deaths). Fifty-six patients (24.8%) experienced severe tamponade. Independent risk factors for severe tamponades were endocardial ablation of ventricular tachycardia, epicardial approach, balloon device ablation, high aspiration volume during pericardiocentesis and structural heart disease. CONCLUSION: The frequency of tamponades is strongly dependent on the type of procedure performed. Overall tamponade-related mortality was low but significantly higher in patients undergoing epicardial procedures. Surgical backup should be considered for patients undergoing complex ventricular tachycardia ablation and left atrial ablation procedures.

Second-generation cryoballoon-based pulmonary vein isolation: Lessons from a five-year follow-up.

BACKGROUND: Pulmonary vein isolation (PVI) using the second-generation cryoballoon (CB2) for atrial fibrillation (AF) treatment has demonstrated encouraging procedural success rates and mid-term results. However, long-term follow-up data on outcome is sparse. The current study is reporting on five-year clinical outcomes following CB2-based PVI in patients with paroxysmal AF (PAF) and persistent AF (PersAF). METHODS: A total of 139 patients underwent index CB2-based PVI patients (PAF: n = 105, 76% and PersAF: n = 34, 34%) in two electrophysiology centers. Freeze-cycle duration was 240 s. After successful PVI a bonus freeze-cycle of the same duration was applied in the first 71 patients while the bonus-freeze was omitted in 68 following patients. Three patients (2.2%) were lost to follow-up. RESULTS: After a median follow-up duration of 60 months (interquartile range: 46, 72 months) 74/136 (54.4%) patients remained in stable sinus rhythm (PAF: 62/104, 59.6%; PersAF: 15/32, 46.9%). Significant differences were observed concerning 5-year clinical outcome between PAF and PersAF patients (p = 0.0315). After a mean of 1.32 ± 0.6 procedures (2nd and 3rd procedure by radiofrequency ablation) and a median follow-up duration of 60 (37, 68) months 90/136 (66.2%) patients remained in stable sinus rhythm (PAF: 72/104 (69.2%), PersAF: 21/32 (65.6%), p = 0.0276). For the comparison of bonus-freeze vs no-bonus-freeze protocols no differences were observed (53.5% vs 57.4%, p = 0.650). CONCLUSIONS: The five-year single-procedure success rate for CB2-based PVI was 54.4% and increased to 66.2% following repeat RF-based procedures. No differences were detected comparing bonus-freeze and no-bonus-freeze protocols.

Reconduction After Second-Generation Cryoballoon-Based Pulmonary Vein Isolation　- Impact of Different Ablation Strategies.

BACKGROUND: The second-generation cryoballoon (CB2) has demonstrated high procedural efficacy and convincing clinical success rates for pulmonary vein isolation (PVI). Nevertheless, data on the impact of different ablations protocols on durability are limited. The aim was to comparing the durability of PVI following 3 different ablation strategies in patients with recurrence of atrial fibrillation or atrial tachycardia undergoing repeat procedures.Methods and Results:In 192 patients, a total of 751 PVs were identified. All PVs were successfully isolated during index PVI. Thirty-one out of 192 (16%) patients were treated with a bonus-freeze protocol (group 1), 67/192 (35%) patients with a no bonus-freeze protocol (group 2), and 94/192 (49%) patients with a time-to-effect-guided protocol (group 3). Persistent PVI was documented in 419/751 (55.8%) PVs, and in 41/192 (21%) patients, all PVs were persistently isolated. The total rate of PV reconnection was not significantly different between the groups (P=0.134) and the comparison of individual PVs revealed no differences (P-values for RSPV: 0.424, RIPV: 0.541, LSPV: 0.788, LIPV: 0.346, LCPV: 0.865). The procedure times were significantly reduced by omitting the bonus-freeze and applying individualized application times (group 1: 123.4±31.5 min, group 2: 112.9±39.8 min, group 3: 86.67±28.4 min, P<0.001). CONCLUSIONS: Comparing 3 common ablation protocols, no differences for durable PVI were detected. Procedure times were significantly reduced by omitting the bonus-freeze cycle and by applying individualized application times.

Radiofrequency or cryoballoon ablation for index pulmonary vein isolation: What is the impact on long-term clinical outcomes after repeat ablation?

AIMS: The current study sought to assess the impact of the utilized energy source during index ablation on long-term clinical outcomes after repeat ablation of atrial fibrillation (AF). Index ablation procedures were either performed using radiofrequency current (RFC) (RFC group) or cryoballoon (CB) ablation (CB group). Repeat ablation was performed by the use of RFC. METHODS: A total of 195 patients (138 RFC group; 57 CB group) with paroxysmal AF were included. All patients had a recurrence of AF following the index ablation procedure. Freedom from AF was estimated with the Kaplan-Meier method. RESULTS: After a 3 years follow-up, the estimated arrhythmia-free survival did not differ between the two groups (RFC group 48% vs CB group 47%, P = .78). During index ablation, procedure times were significantly shorter in the CB group (95 [80, 140] vs 140 [115, 164] minutes, P ≤ .001), whereas fluoroscopy times (16 [11; 22] vs 19 [14; 25] minutes, P = .003), the dose area product (1862 [1203; 2922] vs 3148 [1756; 5888] cGycm2 , P ≤ .001) and the amount of contrast dye (92 ± 32 vs 123 ± 33 mL, P ≤ .001) were significantly lower in the RFC group. During repeat ablation, procedure times were significantly shorter in patients being initially treated with RFC (115 [85; 145] vs 125 [105; 150] minutes, P = .007). There was a trend towards a higher pulmonary vein reconnection rate in the RFC group without meeting statistical significance (P = .074). CONCLUSIONS: In patients with repeat ablation of AF, index RFC or CB ablation are equally effective in terms of freedom from AF. Although CB ablation results in shorter index procedures times, durations of repeat ablation are significantly longer.

Feasibility, safety, and acute efficacy of the fourth-generation cryoballoon for ablation of atrial fibrillation: Another step forward?

BACKGROUND: The second-generation cryoballoon (CB2) is widely used for pulmonary vein (PV) isolation (PVI) in patients with paroxysmal atrial fibrillation (AF). Recently, the novel fourth-generation CB (CB-Advance PRO) was introduced, incorporating a shortened catheter tip. HYPOTHESIS: The aim of this study was to evaluate the feasibility and acute efficacy of PVI using the CB-Advance PRO. METHODS: A total of 200 consecutive patients were analyzed. Hundred patients who underwent PVI due to symptomatic, drug-refractory AF were treated with the CB-Advance PRO (group I) and were included into this multicenter analysis. A group of 100 patients were treated with the CB2 and acted as controls (group II). RESULTS: In total, 739 of 739 PVs (100%) were successfully isolated. There was a nonsignificant trend in the incidence of online registration of PV signals between both groups (group I: 77.9% vs group II: 71.4%, P = .09). Median time to PVI (time to isolation [TTI]) and mean total freezing time were significantly shorter when using the CB-Advance PRO (group I: 33 [23, 50] vs group II: 40 [26, 60] seconds and group I: 166 ± 29 vs group II: 183 ± 38 seconds, P < .01). In three of 100 (3%) patients of group I and one of 100 (1%) patients of group II, a transient phrenic nerve palsy occurred (P = .62). CONCLUSION: The use of the novel CB-Advance PRO is feasible and associated with a significant reduction in mean TTI and mean total freezing time as compared to the CB2.

Initial experience and procedural efficacy of pulmonary vein isolation using the fourth-generation cryoballoon - a step forward?

Background: Cryoballoon (CB)-based pulmonary vein isolation (PVI) is an established treatment modality for patients suffering from paroxysmal or persistent atrial fibrillation (AF). Recently, the novel fourth-generation cryoballoon (CB4) was introduced which mainly provides a 40% shorter distal tip as compared to the second-generation cryoballoon (CB2). This two-centre analysis sought to assess the primary efficacy of the 28 mm CB4 for PVI and the feasibility of real-time signal recordings from the PVs considering the time-to-isolation (TTI).Methods and results: Eighty-four patients with paroxysmal or short-standing persistent AF underwent CB4-based PVI at two different hospitals. Individual freeze-cycle duration was set at TTI + 120 seconds. No bonus freeze was applied. A total of 331 pulmonary veins (PVs) including five left common PVs were identified and all PVs were successfully isolated. Mean freeze-cycle duration was 165.7 ± 31.5 seconds. The mean minimal CB temperature was -45.6 ± 7.6 °C with a real-time PVI visualisation rate of 78% (67/84 (79.8%) RSPVs, 55/84 (65.5%) RIPVs, 67/79 (84.8%) LSPVs, 66/79 (83.5%) LIPVs and 2/5 (40%) LCPV). Transient phrenic nerve palsy occurred in 2/84 (2.4%) patients during cryo-application along the RSPV.Conclusions: The novel CB4 provides both, a high acute efficacy and a high rate of real time electrical PV-recordings, thus facilitating individual ablation strategies based on TTI.

Efficacy and Safety of Cryoballoon Ablation in Patients With Heart Failure and Reduced Left Ventricular Ejection Fraction　- A Multicenter Study.

BACKGROUND: Second-generation cryoballoon (CB2)-based pulmonary vein isolation (PVI) has demonstrated encouraging results in the treatment of atrial fibrillation (AF). This study sought to assess data on the safety, efficacy and clinical success of CB2-based PVI in patients with heart failure (HF) and reduced ejection fraction (HFrEF).Methods and Results:CB2-based PVI was performed in 551 consecutive patients in 3 highly experienced EP centers. Patients with HF and LVEF ≤40% were included (HFrEF group, n=50/551, 9.1%). Data were compared with propensity score-matched patients without HF and preserved left ventricular EF (LVEF) (n=50, control group). The median LVEF was HFrEF: 37% (35, 40) and control: 55% (55, 55), P<0.0001. Major periprocedural complications were registered in 4/50 (8%, HFrEF group) and 3/50 (6%, control group), P=0.695. The 12-month freedom from AF recurrence was 73.1% (95% confidence interval (CI): 61-88, HFrEF group) and 72.6% (95% CI: 61-87, control group), P=0.25. NYHA class decreased from 2.4±0.8 (baseline) to 1.7±0.8 at 12-month follow-up (P<0.0001). LVEF improved from a median of 37% (35, 40) prior to ablation to a median of 55% (40, 55), P<0.0001. CONCLUSIONS: CB2-based PVI in patients with HFrEF appeared to be safe, was associated with comparable periprocedural complications and showed promising clinical success rates equal to those for patients with preserved LVEF. NYHA class and LVEF significantly improved at 12-month follow-up.