The Impact of Left Atrial Surface Area and the Second Generation Cryoballoon on Clinical Outcome of Atrial Fibrillation Cryoablation.

AIMS: In this observational study, we examine the significance of the left atrial (LA) surface area and compare the clinical usage of the Arctic Front Advance (CBA) versus Arctic Front (CB) cryoballoon with the intent to investigate the impact of each in terms of long-term freedom from atrial fibrillation (AF) for patients with nonvalvular AF. METHODS: Pulmonary vein isolation (PVI) was performed while using a cryoballoon ablation catheter in conjunction with an intraluminal circular diagnostic mapping catheter, Achieve. The consecutive patients ablated with CBA were matched with patients previously ablated with CB, using propensity score matching. The primary endpoint of this observational single-center retrospective study was the first observation of electrocardiogram-documented recurrence of atrial arrhythmias lasting >30 seconds. RESULTS: The patient demographic data were similar in the CBA- and CB-group (N = 188 patients each group). In all patients in the CBA-group and in 95% of the patients in the CB group, acute procedural PVI of all veins was achieved with the single usage of a 28-mm cryoballoon. The one-year freedom from atrial arrhythmias was significantly better in the CBA- versus the CB-group of patients, 90% versus 64%, respectively. During 15-month clinical follow-up in CBA group, patients with LA area above 23 cm(2) were more likely to experience recurrence of AF (23%) than patients with LA area below 23 cm(2) (7%). CONCLUSIONS: Comparing one-year outcomes, the CBA is superior to the CB with regards to maintenance of normal sinus rhythm. When using the CBA catheter, an enlarged LA is associated with a higher recurrence of arrhythmia.

Ipsilateral circumferential radiofrequency ablation of atrial fibrillation with irrigated tip catheter: long-term outcome and pre-procedural predictors.

BACKGROUND: Predictors of long-term outcome of atrial fibrillation (AF) ablation are unknown. The predictors of 5-year follow-up (FU) after single ipsilateral circumferential antrum pulmonary vein isolation (PVI) with irrigated tip catheter were investigated. METHODS AND RESULTS: In 356 patients (74% male) with AF (44% paroxysmal AF [PAF]) PVI was performed. Success was defined as absence of AF, atrial flutter or tachycardia (AFLAT) recurrence. A total of 161 patients (45%) were free of AFLAT. The univariate predictors of AFLAT recurrence were: type of AF (non-PAF vs. PAF, P=0.0001), size of LA (normalized left atrium area [NLA] ≥11.5 vs. NLA <11.5, P=0.0001), renal function (glomerular filtration rate [GFR] <68ml/min vs. GFR ≥68ml/min, P=0.001) and hypertension (HT vs. no HT, P=0.025). The independent predictors of AFLAT-free survival were non-PAF (hazard ratio [HR], 1.67; 95% confidence interval [CI]: 1.23-2.26, P=0.0005), NLA ≥11.5 (HR, 1.40; 95% CI: 1.03-1.90, P=0.007) and GFR <68ml/min (HR, 1.70; 95% CI: 1.21-2.37, P=0.008). CONCLUSIONS: Single PVI results in a moderate success rate in patients with AF during 5-year FU without the use of a 3-D mapping system. Higher success was observed in patients with PAF, non-enlarged LA and good renal function.

Repeated catheter ablation of atrial fibrillation: how to predict outcome?

BACKGROUND: Pre-procedural predictors (PP) of atrial fibrillation (AF) recurrence (AFR) after repeated catheter ablation of AF (RCAF) are unknown. The aim of this study was identification of PP of outcome after RCAF. METHODS AND RESULTS: In 213 patients (73% male) with drug-refractory AF (47% paroxysmal AF; PAF) RCAF was performed. CHADS2, CHA2DS2-VASc and ALARMEc (AF type, Left Atrium size, Renal insufficiency, MEtabolic syndrome, cardiomyopathy) scores were calculated for each patient. Complete success was defined as no AFR. After RCAF, 125 patients (59%) were free of atrial flutter or atrial tachycardia (AFLAT) on long-term follow-up (FU). The univariate predictors of AFR were: type of AF (non-PAF vs. PAF, P=0.001), normalized left atrium area (NLA ≥10.25 vs. NLA <10.25, P=0.012) and estimated glomerular filtration rate (<68ml/min vs. ≥68ml/min, P=0.048). The independent predictors of AFLAT-free survival after RCAF were non-PAF (P=0.002) and NLA ≥10.25 (P=0.018). Among combined predictors, only ALARMEc score, and neither CHADS2 or CHA2DS2-VASc, predicted outcome after RCAF (P<0.0001). CONCLUSIONS: RCAF results in a moderate success rate on very long-term FU. Lower success was observed in patients with non-PAF and enlarged LA. ALARMEc score allows for clear description of expected outcome after RCAF.

Cryoballoon ablation of paroxysmal atrial fibrillation: 5-year outcome after single procedure and predictors of success.

AIMS: Long-term efficacy following cryoballoon (CB) ablation of atrial fibrillation (AF) remains unknown. This study describes 5 years follow-up results and predictors of success of CB ablation in patients with paroxysmal atrial fibrillation (PAF). METHODS AND RESULTS: In total, 163 patients were enrolled with symptomatic, drug refractory PAF. Pulmonary vein isolation (PVI) with CB technique was performed. Primary endpoint of this consecutive single-centre study was first electrocardiogram-documented recurrence of AF, atrial tachycardia or atrial flutter (AFLAT). Five years success rate after single CB ablation was 53%. In 70% of the patients acute complete PVI was achieved with a single 28 mm balloon. The univariate predictors of AFLAT recurrence were (1) size of left atrium, with normalized left atrium (NLA) ≥10.25 [hazard ratios (HR) of 1.81, 95% confidence interval (CI): 1.28-2.56] when compared with NLA <10.25 (35% vs. 53%, P = 0.0001) and (2) renal function, with impaired glomerular filtration rate (GFR) <80 ml/min (HR of 1.26, 95% CI: 1.02-1.57) when compared with GFR ≥80 ml/min (45% vs. 53%, P = 0.041). Normalized left atrium ≥10.25 was the sole independent predictor for outcome (HR 2.11; 95% CI: 1.34-3.31; P = 0.0001). CONCLUSIONS: Sinus rhythm can be maintained in a substantial proportion of patients with PAF even 5 years after circumferential PVI using CB ablation. The rate of decline in freedom from AFLAT was highest within the first 12 months after the index procedure. The patients with enlarged left atrium and/or impaired renal function have lower outcome.

Impact of impaired renal function and metabolic syndrome on the recurrence of atrial fibrillation after catheter ablation: a long term follow-up.

BACKGROUND: The goal of this study was to analyze impact of metabolic syndrome (MetS) and impaired renal function on long-term follow-up after catheter ablation of atrial fibrillation (AF). METHODS AND RESULTS: A total of 702 consecutive patients with AF (age = 58 year, history of AF = 5 year, male = 478, paroxysmal atrial fibrillation = 416, coronary artery disease = 62, hypertension = 487) considered for catheter ablation were enrolled in the study. The MetS was diagnosed at admission in 276 patients. The renal function was estimated by glomerular filtration rate (eGFR). Pulmonary vein isolation (PVI) was performed either with cryoballoon technique (n = 260) or circumferential PVI (n = 442) with a 3.5-mm irrigated tip catheter. A 7-day-Holter electrocardiogram was performed at each follow-up visit. Any episode of documented AF after an initial 3-month blanking period was considered as clinical endpoint. Out of 702 patients, 370 (52.7%) were free of AF recurrences at median follow-up of 15 six interquartile range (12.7-42.3) months. The patients with MetS had significantly lower success rate than those without (128/276 (46.4%) vs 242/426 (56.8%), P = 0.006). Among 103 patients with eGFR < 68 mL/min only 35 (34%) were free of recurrences compared with 335/599 (55.9%) in patients with GFR ≥ 68 mL/min (P = 0.001). Both parameters were revealed in multivariate analysis to be independent predictors for outcome after catheter ablation. CONCLUSION: The results of our study clearly demonstrated that outcome after 1st catheter ablation of AF is poor in patients with MetS and/or impaired renal function. This observation has a potential clinical impact for the follow up management of these patients.

Acute and long-term results of PVI at antrum using a novel high-density mapping catheter without help of 3D electro-anatomic mapping in patients with paroxysmal and chronic atrial fibrillation.

PURPOSE: Multi-electrode circumferential mapping catheters have been developed by several manufacturers to facilitate catheter ablation procedures for atrial fibrillation (AF). We tested the effectiveness and safety of a conventional, fully endocardial electrogram-guided circumferential antrum isolation (PVI) with a novel mapping device. METHODS: The study enrolled 250 consecutive patients with paroxysmal or chronic AF. High-density (HD) mapping of the pulmonary veins was performed with the HD Mesh Mapper (HDMM; Bard Electrophysiology, Lowell, MA, USA). The device was not constructed for radiofrequency energy delivery. Antral PVI was performed by irrigated radiofrequency application around the HDMM. Entry and exit conduction block, as well as decreased local electrode amplitude, were endpoints for acute successful ablation. Primary endpoint of the study was the AF free event probability during follow-up. As secondary endpoints, the acute results and related complications were determined. RESULTS: In 984 of 1,002 pulmonary vein (PV, 98.2%), signals were characterized as PV potentials by mapping the proximal part of the PV and the antrum. We achieved a complete antrum ablation in front of the 25-mm ring of the MESH Mapper in 95% of the PV in all patients. In difficult anatomic relationships, the repositioning of the mapping catheter could be necessary. The median follow-up time was 20.8 and 15.6 months in patients with paroxysmal and chronic AF, respectively. Log Rang test revealed a probability to be free from AF episodes of 71.2% and 49.4% after one ablation procedure and improved in chronic AF after a second procedure (71.1%). CONCLUSION: Our study demonstrates satisfactory success rate regarding the safety and long-term results in patients both with paroxysmal and persistent AF when a 3D mapping system is not being implemented. The study underlines the importance of a continuous signal analysis during the ablation procedure even with a conventional mapping system.

Incidence of stroke in paroxysmal versus sustained atrial fibrillation in patients taking oral anticoagulation or combined antiplatelet therapy: an ACTIVE W Substudy.

OBJECTIVES: Our goal was to determine the risk of stroke or non-cerebral embolism associated with paroxysmal compared with sustained atrial fibrillation (AF). BACKGROUND: The risk of stroke and non-cerebral embolism and the efficacy of oral anticoagulation (OAC) in paroxysmal AF as compared with sustained AF are not precisely known. METHODS: The ACTIVE W (Atrial Fibrillation Clopidogrel Trial With Irbesartan for Prevention of Vascular Events) was a trial comparing OAC to combined antiplatelet therapy with aspirin and clopidogrel for prevention of vascular events in 6,706 AF patients. The incidence of thromboembolic events and major bleeds were compared in patients with paroxysmal AF (n = 1,202) and persistent or permanent AF (n = 5,495). RESULTS: Patients with paroxysmal AF were younger, had a shorter AF history, more hypertension, and less valvular disease, heart failure, and diabetes mellitus than patients with sustained AF. At baseline, patients with paroxysmal AF had a CHADS2 (cardiac failure, hypertension, age, diabetes, stroke [doubled]) risk score of 1.79 +/- 1.03 compared with 2.04 +/- 1.12 in patients with sustained AF (p < 0.00001). The annualized risk of stroke or non-central nervous system (CNS) systemic embolism was 2.0 in paroxysmal AF compared with 2.2 in sustained AF (relative risk 0.87, 95% confidence interval [CI] 0.59 to 1.30, p = 0.496). After adjusting for confounding baseline variables, the relative risk was 0.94 (95% CI 0.63 to 1.40, p = 0.755). The incidence of stroke and non-CNS embolism was lower for patients treated with OAC irrespective of type of AF. There were more bleedings of any type in patients receiving clopidogrel plus aspirin, irrespective of the type of AF. CONCLUSIONS: Patients with paroxysmal AF treated with aspirin plus clopidogrel or OAC have a similar risk for thromboembolic events than patients with sustained AF. This risk can be significantly lowered with OAC. (The ACTIVE W trial; http://www.clinicaltrials.gov/ct/show/NCT00243178;NCT00243178).