Jean-Francois Roux

Anticoagulation Management Pre- and Post Atrial Fibrillation Ablation: A Survey of Canadian Centres

BACKGROUNDnAnticoagulation in patients undergoing atrial fibrillation (AF) ablation is crucial to minimize the risk of thromboembolic complications. There are broad ranges of approaches to anticoagulation management pre and post AF ablation procedures. The purpose of this study was to determine the anticoagulation strategies currently in use in patients peri- and post AF ablation in Canada.nnnMETHODSnA Web-based national survey of electrophysiologists performing AF ablation in Canada collected data regarding anticoagulation practice prior to ablation, periprocedural bridging, and duration of postablation anticoagulation.nnnRESULTSnThe survey was completed by 36 (97%) of the 37 electrophysiologists performing AF ablation across Canada. Prior to AF ablation, 58% of electrophysiologists started anticoagulation for patients with paroxysmal AF CHADS(2) scores of 0 to 1, 92% for paroxysmal AF CHADS(2) scores ≥ 2, 83% for persistent AF CHADS(2) scores of 0 to 1, and 97% for persistent AF CHADS(2) scores ≥ 2. For patients with CHADS(2) 0 to 1, warfarin was continued for at least 3 months by most physicians (89% for paroxysmal and 94% for persistent AF). For patients with CHADS(2) ≥ 2 and with no recurrence of AF at 1 year post ablation, 89% of physicians continued warfarin.nnnCONCLUSIONSnAlthough guidelines recommend long-term anticoagulation in patients with CHADS(2) ≥ 2, 11% of physicians would discontinue warfarin in patients with no evidence of recurrent AF 1 year post successful ablation. Significant heterogeneity exists regarding periprocedural anticoagulation management in clinical practice. Clinical trial evidence is required to guide optimal periprocedural anticoagulation and therapeutic decisions regarding long-term anticoagulation after an apparently successful catheter ablation for AF.

Concordance Between an Electroanatomic Mapping System and Cardiac MRI in Arrhythmogenic Right Ventricular Cardiomyopathy

A 29‐year‐old man presenting with syncopal ventricular tachycardia was diagnosed with arrhythmogenic right ventricular (RV) cardiomyopathy. Cardiac magnetic resonance imaging (MRI) revealed an unequivocal dyskinetic segment at the basal portion of the RV lateral free wall. Three‐dimensional electroanatomic voltage mapping using the EnSite NavX™ system recorded a low voltage area corresponding to the diseased portion of the right ventricle identified by MRI. This report describes concordance between cardiac MRI and this novel mapping system in arrhythmogenic RV cardiomyopathy.

Intracardiac echo-facilitated 3D electroanatomical mapping of ventricular arrhythmias from the papillary muscles: assessing the 'fourth dimension' during ablation.

Aims Ventricular arrhythmias (VA) originating from a papillary muscle (PM) have recently been described as a distinct clinical entity with peculiar features that make its treatment with catheter ablation challenging. Here, we report our experience using an intracardiac echo-facilitated 3D electroanatomical mapping approach in a case series of patients undergoing ablation for PM VA. Methods and results Sixteen patients who underwent catheter ablation for ventricular tachycardia (VT) or symptomatic premature ventricular contractions originating from left ventricular PMs were included in the study. A total of 24 procedures (mean 1.5 per patient) were performed: 15 using a retrograde aortic approach and 9 using a transseptal approach. Integrated intracardiac ultrasound for 3D electroanatomical mapping was used in 15 of the 24 procedures. The posteromedial PM was the most frequent culprit for the clinical arrhythmia, and the body was the part of the PM most likely to be the successful site for ablation. The site of ablation was identified based on the best pace map matching the clinical arrhythmia and the site of earliest the activation. At a mean follow-up of 10.5 ± 7 months, only two patients had recurrent arrhythmias following a repeat ablation procedure. Conclusion An echo-facilitated 3D electroanatomical mapping allows for real-time creation of precise geometries of cardiac chambers and endocavitary structures. This is useful during procedures such as catheter ablation of VAs originating from PMs, which require detailed representation of anatomical landmarks. Routine adoption of this technique should be considered to improve outcomes of PM VA ablation.

Appropriate Use of Antithrombotic Medication in Canadian Patients With Nonvalvular Atrial Fibrillation

This national chart audit of 7,019 patients with nonvalvular atrial fibrillation (AF) from 735 primary care physician practices sought to examine the management of Canadian patients with AF through an evidence-based, guideline-recommended approach. The appropriate use of oral anticoagulants (OACs) in this patient population and the potential factors guiding OAC choice were examined. Suboptimal dosing was seen. In patients on warfarin, 30.9% had not achieved a time in therapeutic range (TTR) in excess of 65% and, despite current Canadian guideline recommendations, were continued on warfarin rather than one of the novel OACs. In patients who received no antithrombotic therapy, 65.5% met criteria for treatment with an OAC. In addition, 62.8% of patients who were treated with acetylsalicylic acid monotherapy met guideline criteria for the use of an OAC. In those patients treated with an OAC, 24.8% were not on the recommended dose based on the product monograph or, if on warfarin, had a TTR <65%. Of the patients on novel OACs (NOACs), 7.4% of patients were underdosed, whereas overdosing was seen in 4.3%. Factors that may have contributed to dosing outside recommendations included underestimation of stroke risk, overestimation of bleed risk, compliance concerns, and lack of provincial reimbursement. In conclusion, significant correctable gaps remain in optimal treatment for stroke prevention in AF.

Cryoablation for Ventricular Arrhythmias Arising From the Papillary Muscles of the Left Ventricle Guided by Intracardiac Echocardiography and Image Integration

OBJECTIVESnThis case series reports outcomes and complications of catheter cryoablation at the papillary muscles (PM) of the left ventricle (LV).nnnBACKGROUNDnCatheter radiofrequency ablation is an effective treatment for ventricular arrhythmias (VAs) arising from the PM of the LV. The use of cryoablation at PMs has not been described.nnnMETHODSnTen patients (70% men; median age: 38 years [range: 34 to 45 years]) with drug-refractory premature ventricular contractions or ventricular tachycardia underwent catheter cryoablation. VAs were localized using 3-dimensional (3D) mapping, multidetector computed tomography, and intracardiac echocardiography, with arrhythmia foci being mapped at either the anterolateral PM or posteromedial papillary muscle (PMPM) of the LV. Focal ablation, up to 240 s with freeze-thaw-freeze cycles was performed using an 8-mm cryoablation catheter via a transmitral approach.nnnRESULTSnTermination of ventricular arrhythmia was observed in all 10 patients during ablation. Median follow-up wasxa06xa0months after ablation. The PMPM had higher prevalence of clinical arrhythmias (100% PMPM VAs vs. 10% anterolateral PM VAs). The PM base was the most frequent site of origin of the arrhythmias (60% of patients). Pace-mapping showedxa0≥11/12 match in all treated PM at the site of effective lesion. All VAs arising from the base of thexa0PM showed Purkinje potentials. There were no post-procedure complications. VA recurred in 1 patient.nnnCONCLUSIONSnCryoablation for arrhythmias arising from the PMs of the LV can be performed, and is a safe and effective alternative energy source for ablation.

State-of-the-Art ReviewA Systematic Review on the Progression of Paroxysmal to Persistent Atrial Fibrillation: Shedding New Light on the Effects of Catheter Ablation

The progression from paroxysmal atrial fibrillation (AF) to persistent or long-term persistent forms has recently gained increasing attention. A growing amount of data has shown a significant morbidity and mortality associated with the transition. The aim of our systematic review was to assess the evidence regarding AF progression rates with different management approaches. Electronic databases were searched by using text words and relevant indexing to capture data on AF progression. Studies that considered progression from paroxysmal AF to a persistent or permanent form were included. The papers collected were divided into 2 groups: 1) general population studies (with almost exclusively medical therapy); and 2) studies that consider progression of AF subsequent to AF ablation. Twenty-one studies were included in the first group and 8 in the second group. In the first group, percentage of AF progression at 1 year ranged from 10% to 20%. Studies that included a longer follow-up detected a higher percentage of progression (from 50% to 77% after 12xa0years). In patients treated with catheter ablation, the percentage of progression was significantly lower (from 2.4% to 2.7% at 5 years follow-up). The percentage of progression after catheter ablation did not change according to duration of follow-up. AF ablation is associated with significantly reduced progression to persistent forms compared with studies in the general population. Prevention of long-term AF progression may be a clinically relevant outcome after AF ablation. Further research is required to determine whether delaying progression of AF by catheter ablation reduces morbidity and mortality.

Arrhythmic Risk Following Recovery of Left Ventricular Ejection Fraction in Patients with Primary Prevention ICD.

Left ventricular ejection fraction (LVEF) recovers during follow‐up in a significant proportion of patients implanted with a cardioverter defibrillator (ICD) for primary prevention. Little is known about the midterm arrhythmic risk in this population, particularly in relation to the presence or absence of ischemic cardiomyopathy.

The Effect of Aggressive Blood Pressure Control on the Recurrence of Atrial Fibrillation After Catheter Ablation: A Randomized, Open Label, Clinical Trial (Substrate Modification with Aggressive Blood Pressure Control: SMAC- AF)

Background: Radiofrequency catheter ablation for atrial fibrillation has become an important therapy for AF; however, recurrence rates remain high. We proposed to determine whether aggressive blood pressure (BP) lowering prevents recurrent atrial fibrillation (AF) after catheter ablation in patients with AF and a high symptom burden.nnMethods: We randomly assigned 184 patients with AF and a BP >130/80 mm Hg to aggressive BP (target 30 seconds, determined 3 months beyond catheter ablation by a blinded end-point evaluation.nnResults: The median follow-up was 14 months. At 6 months, the mean systolic BP was 123.2±13.2 mm Hg in the aggressive BP treatment group versus 135.4±15.7 mm Hg ( P <0.001) in the standard treatment group. The primary outcome occurred in 106 patients, 54 (61.4%) in the aggressive BP treatment group compared with 52 (61.2%) in the standard treatment group (hazard ratio=0.94; 95% confidence interval, 0.65–1.38; P =0.763). In the prespecified subgroup analysis of the influence of age, patients ≥61 years of age had a lower primary outcome event rate with aggressive BP (hazard ratio=0.58; 95% confidence interval, 0.34–0.97; P =0.013). There was a higher rate of hypotension requiring medication adjustment in the aggressive BP group (26% versus 0%).nnConclusions: In this study, this duration of aggressive BP treatment did not reduce atrial arrhythmia recurrence after catheter ablation for AF but resulted in more hypotension.nnClinical Trial Registration: URL: . Unique identifier: [NCT00438113][1].nn# Clinical Perspective {#article-title-33}nn [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00438113&atom=%2Fcirculationaha%2F135%2F19%2F1788.atomBackground: Radiofrequency catheter ablation for atrial fibrillation has become an important therapy for AF; however, recurrence rates remain high. We proposed to determine whether aggressive blood pressure (BP) lowering prevents recurrent atrial fibrillation (AF) after catheter ablation in patients with AF and a high symptom burden. Methods: We randomly assigned 184 patients with AF and a BP >130/80 mm Hg to aggressive BP (target <120/80 mm Hg) or standard BP (target <140/90 mm Hg) treatment before their scheduled AF catheter ablation. The primary outcome was symptomatic recurrence of AF/atrial tachycardia/atrial flutter lasting >30 seconds, determined 3 months beyond catheter ablation by a blinded end-point evaluation. Results: The median follow-up was 14 months. At 6 months, the mean systolic BP was 123.2±13.2 mm Hg in the aggressive BP treatment group versus 135.4±15.7 mm Hg (P<0.001) in the standard treatment group. The primary outcome occurred in 106 patients, 54 (61.4%) in the aggressive BP treatment group compared with 52 (61.2%) in the standard treatment group (hazard ratio=0.94; 95% confidence interval, 0.65–1.38; P=0.763). In the prespecified subgroup analysis of the influence of age, patients ≥61 years of age had a lower primary outcome event rate with aggressive BP (hazard ratio=0.58; 95% confidence interval, 0.34–0.97; P=0.013). There was a higher rate of hypotension requiring medication adjustment in the aggressive BP group (26% versus 0%). Conclusions: In this study, this duration of aggressive BP treatment did not reduce atrial arrhythmia recurrence after catheter ablation for AF but resulted in more hypotension. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00438113.

Real-life experience with a new anticoagulation regimen for patients undergoing left-sided ablation procedures

Background Current guidelines for anticoagulation during left-sided procedures recommend the administration of unfractionated heparin (UFH) with an initial bolus of 50–100 U/kg, followed by continuous infusion to maintain an activated clotting time (ACT) ≥ 300 s. Our objective was to compare the effectiveness of this standard regimen (100 U/kg bolus) to a more aggressive approach (200 U/kg bolus). Methods We collected data on a series of consecutive patients undergoing left sided ablation procedures. Patients with an INR ≥2.0 on the day of the procedure were excluded. Procedural anticoagulation was performed using one of two UFH regimens: 1) 100 U/kg bolus, followed by 10 U/kg/hour infusion or 2) 200 U/kg bolus, followed by 20 U/kg/hour infusion. ACT was measured 10 min after the second bolus and then controlled every 20 min. Heparin was titrated throughout the procedure to maintain an ACT 300–400 s. Results 145 consecutive patients were included in the study: 34 received an initial bolus of 100 U/kg and 111 received 200 U/kg. The mean time required to reach an ACT ≥300 s was 15.25 min (95% CI 12.97–17.03) in the 200 U/kg group and 51.23 min (95% CI 40.65–61.81) in the 100 U/kg group (p < 0.001). There was no difference between groups with regard to thromboembolic or hemorrhagic complications. Conclusion Current anticoagulation guidelines for left-sided ablation procedures almost universally fail to achieve an initial ACT ≥300 s. A 200 U/kg heparin bolus is much more effective to promptly reach the target ACT, with a low rate of overshoot.

Quality of life with ablation or medical therapy for ventricular arrhythmias: A substudy of VANISH

We compared health‐related quality of life (HRQoL) in patients randomized to escalated therapy and those randomized to ablation for ventricular tachycardia in the VANISH trial.