New-onset atrial fibrillation detected by ambulatory ECG monitoring after transcatheter aortic valve implantation.

BACKGROUND: Little is known about the occurrence of subclinical new-onset atrial fibrillation (NOAF) after transcatheter aortic valve implantation (TAVI). AIMS: We aimed to evaluate the incidence, predictors, and clinical impact of subclinical NOAF after TAVI. METHODS: This was a multicentre study, including patients with aortic stenosis (AS) and no previous atrial fibrillation undergoing TAVI, with continuous ambulatory electrocardiogram (AECG) monitoring after TAVI. RESULTS: A total of 700 patients (79±8 years, 49% female, Society of Thoracic Surgeons score 2.9% [1.9-4.0]) undergoing transarterial TAVI were included (85% balloon-expandable valves). AECG was started 1 (0-1) day after TAVI (monitoring time: 14121314 days). NOAF was detected in 49 patients (7%), with a median duration of 185 (43-421) minutes (atrial fibrillation burden of 0.7% [0.3-2.8]). Anticoagulation was started in 25 NOAF patients (51%). No differences were found in baseline or procedural characteristics, except for a higher AS severity in the NOAF group (peak gradient: no NOAF: 71.9±23.5 mmHg vs NOAF: 85.2±23.8 mmHg; p=0.024; mean gradient: no NOAF: 44.4±14.7 mmHg vs NOAF: 53.8±16.8 mmHg; p=0.004). In the multivariable analysis, the baseline mean transaortic gradient was associated with a higher risk of NOAF after TAVI (odds ratio 1.04, 95% confidence interval: 1.01-1.06 for each mmHg; p=0.006). There were no differences between groups in all-cause mortality (no NOAF: 4.7% vs NOAF: 0%; p=0.122), stroke (no NOAF: 1.4% vs NOAF: 2.0%; p=0.723), or bleeding (no NOAF: 1.9% vs NOAF: 4.1%; p=0.288) from the 30-day to 1-year follow-up. CONCLUSIONS: NOAF detected with AECG occurred in 7% of TAVI recipients and was associated with a higher AS severity. NOAF detection determined the start of anticoagulation therapy in about half of the patients, and it was not associated with an increased risk of clinical events at 1-year follow-up.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation.

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation.

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .

Health Security Perceptions: Initial Psychometric Analysis of the Construct of Health Security in Chronic Illness Among Patients With a Cardiac Device.

Scale measuring the construct of "health security in chronic illness" (HSCI) was piloted in Canadian cardiac device patients (N = 176) enrolled in a remote-monitoring study at 2 timepoints. Analysis revealed a 2-factor solution, labeled as "support" and "certainty". Patients reported receiving less support over time, but consistent health certainty. Patients with implantable cardioverter defibrillators felt less secure over time and reported lower levels of health security in chronic illness than pacemaker patients.

Une échelle mesurant le concept de la « sécurité en matière de santé en présence d'une maladie chronique ¼ a fait l'objet d'un projet pilote auprès de patients canadiens porteurs de dispositifs cardiaques (N = 176) inscrits dans une étude de télésurveillance comportant deux évaluations. L'analyse a révélé une solution à deux facteurs, soit le soutien et la certitude. Les patients ont déclaré qu'ils recevaient moins de soutien au fil du temps, mais que la certitude quant à leur santé était constante. Les porteurs d'un défibrillateur cardioverteur implantable se sentaient moins en sécurité au fil du temps et signalaient de plus bas niveaux de sécurité en matière de santé, relativement à leur maladie chronique, que les porteurs d'un stimulateur cardiaque.

Rationale and Design of the Randomized Bayesian Multicenter COME-TAVI Trial in Patients With a New Onset Left Bundle Branch Block.

Patients with new-onset left bundle branch block (LBBB) after transcatheter aortic valve implantation (TAVI) are at risk of developing delayed high-degree atrioventricular block. Management of new-onset LBBB post-TAVI remains controversial. In the Comparison of a Clinical Monitoring Strategy Versus Electrophysiology-Guided Algorithmic Approach in Patients With a New LBBB After TAVI (COME-TAVI) trial, consenting patients with new-onset LBBB that persists on day 2 after TAVI, meeting exclusion/inclusion criteria, are randomized to an electrophysiological study (EPS)-guided approach or 30-day electrocardiographic monitoring. In the EPS-guided approach, patients with a His to ventricle (HV) interval ≥ 65 ms undergo permanent pacemaker implantation. Patients randomized to noninvasive monitoring receive a wearable continuous electrocardiographic recording and transmitting device for 30 days. Follow-up will be performed at 3, 6, and 12 months. The primary endpoint is a composite outcome designed to capture net clinical benefit. The endpoint incorporates major consequences of both strategies in patients with new-onset LBBB after TAVI, as follows: (i) sudden cardiac death; (ii) syncope; (iii) atrioventricular conduction disorder requiring a pacemaker (for a class I or IIa indication); and (iv) complications related to the pacemaker or EPS. The trial incorporates a Bayesian design with a noninformative prior, outcome-adaptive randomization (initially 1:1), and 2 prespecified interim analyses once 25% and 50% of the anticipated number of primary endpoints are reached. The trial is event-driven, with an anticipated upper limit of 452 patients required to reach 77 primary outcome events over 12 months of follow-up. In summary, the aim of this Bayesian multicentre randomized trial is to compare 2 management strategies in patients with new-onset LBBB post-TAVI-an EPS-guided approach vs noninvasive 30-day monitoring. Trial registration number: NCT03303612.

Les patients chez qui un bloc de branche gauche (BBG) est récemment apparu à la suite de l'implantation valvulaire aortique par cathéter (IVAC) présentent un risque de bloc auriculoventriculaire de haut degré tardif. La prise en charge d'un BBG récemment apparu après une IVAC demeure controversée. Dans le cadre de l'essai COME-TAVI (Comparison of a ClinicalMonitoring Strategy VersusElectrophysiology-Guided Algorithmic Approach in Patients With a New LBBB AfterTAVI, ou comparaison d'une stratégie de surveillance clinique, par rapport à une approche guidée par étude électrophysiologique et fondée sur un algorithme, chez des patients présentant un BBG d'apparition récente à la suite d'une IVAC), des patients qui présentent un BBG d'apparition récente persistant le 2e jour après une IVAC, qui répondent aux critères d'admissibilité et qui ont donné leur consentement sont répartis aléatoirement pour être suivis à l'aide d'une approche guidée par une étude électrophysiologique (EEP) ou faire l'objet d'une surveillance électrocardiographique d'une durée de 30 jours. Un stimulateur cardiaque est implanté chez les patients du groupe de l'EEP dont l'intervalle HV (temps de conduction dans le tronc du faisceau de His jusqu'aux ventricules) est ≥ 65 ms. Les patients du groupe de surveillance non invasive reçoivent un dispositif portable d'enregistrement et de transmission continue de données électrocardiographiques pour une période de 30 jours. Le suivi sera réalisé aux 3e, 6e et 12e mois. Le critère d'évaluation principal est un paramètre composite conçu afin de saisir le bienfait clinique net. Il comprend les conséquences majeures des deux stratégies chez les patients présentant un BBG d'apparition récente après une IVAC, comme suit : (i) mort subite d'origine cardiaque; (ii) syncope; (iii) trouble de la conduction auriculoventriculaire nécessitant la pose d'un stimulateur cardiaque (pour une indication de classe I ou IIa); et (iv) complications relatives au stimulateur cardiaque ou à l'EEP. L'essai intègre une conception bayésienne avec une répartition aléatoire (dans un rapport initial de 1:1) antérieure non informative adaptée aux résultats et deux analyses intermédiaires définies au préalable lorsque 25 % et 50 % du nombre anticipé des critères d'évaluation principaux seront atteints. L'essai est axé sur les événements, et la limite supérieure anticipée pour atteindre 77 événements relatifs aux critères d'évaluation principaux sur 12 mois de suivi est de 452 patients. En résumé, l'objectif de cet essai bayésien multicentrique à répartition aléatoire est de comparer deux stratégies de prise en charge de patients présentant un BBG d'apparition récente après une IVAC, soit une approche guidée par une EEP, par rapport à une surveillance non invasive de 30 jours. Trial registration number: NCT03303612.

Study of ECG-derived atrial fibrillatory rate for prediction of the outcome of cardioversion of short duration atrial fibrillation (CASAF).

AIMS: The present study aimed at testing the hypothesis that atrial fibrillatory rate (AFR) is predictive of sinus rhythm maintenance after electrical cardioversion. METHODS AND RESULTS: The study comprised 32 patients admitted for cardioversion of atrial fibrillation of short duration (mean duration 3.8 ± 7.7 days). AFR was estimated using frequency power spectrum analysis of QRST-cancelled ECG. At six-weeks follow-up 22% of the patients had relapsed to AF. The pre-cardioversion mean AFR of those was 332 ± 64 fpm compared to 378 ± 59 fpm among patients maintaining sinus rhythm (p = 0.12). CONCLUSION: AFR was not predictive of sinus rhythm maintenance in patients of short duration AF undergoing cardioversion. This is in stark contrast with the earlier reported findings. CLINICAL TRIAL REGISTRATION: NCT02112318 (http://www. CLINICALTRIALS: gov).

Leucocyte-derived micro-RNAs as candidate biomarkers in Brugada syndrome.

AIMS: Risk stratification for sudden cardiac death in patients with Brugada syndrome remains a major challenge. Contemporary risk prediction models have only modest predictive value. The aim of this study was to assess the role of micro-RNAs from peripheral blood as candidate biomarkers in Brugada syndrome. METHODS AND RESULTS: In this prospective study, Brugada patients and unaffected control individuals were enrolled for analysis of leucocyte-derived microRNAs (miRNAs) levels. Expression levels of 798 different circulating miRNAs were analysed on the NanoString® nCounter platform. All results were cross-validated by using a quantitative polymerase chain reaction. Micro-RNA expression levels of Brugada patients were compared with clinical data. A total of 21 definite Brugada patients (38% with a history of ventricular arrhythmia or cardiac arrest) and 30 unaffected control individuals were included in the study. Micro-RNA analysis showed a distinct expression profile in Brugada patients with 42 differentially expressed markers (38 up-regulated, 4 down-regulated miRNAs). The symptom status of Brugada patients was associated with a distinct miRNA signature. Micro-RNAs 145-5p and 585-3p were significantly up-regulated in symptomatic Brugada patients (P = 0.04). Incorporating miRNAs 145-5p and 585-3p into a multivariable model demonstrated significantly increased symptom prediction (area under the curve = 0.96; 95% confidence interval: 0.88-1.00). CONCLUSION: Brugada patients display a distinct miRNA expression profile compared with unaffected control individuals. There is also evidence that certain miRNAs (miR-145-5p and miR-585-3p) are associated with the symptom status of Brugada patients. The results suggest the principal utility of leucocyte-derived miRNAs as prognostic biomarkers for Brugada syndrome.

Ventricular Tachycardia and ICD Therapy Burden With Catheter Ablation Versus Escalated Antiarrhythmic Drug Therapy.

BACKGROUND: Catheter ablation improves ventricular tachycardia (VT) event-free (time to event) survival in patients with antiarrhythmic drug (AAD)-refractory VT and previous myocardial infarction (MI). The effects of ablation on recurrent VT and implantable cardioverter-defibrillator (ICD) therapy (burden) have yet to be investigated. OBJECTIVES: This study sought to compare the VT and ICD therapy burden following treatment with either ablation or escalated AAD therapy among patients with VT and previous MI in the VANISH (Ventricular tachycardia AblatioN versus escalated antiarrhythmic drug therapy in ISchemic Heart disease) trial. METHODS: The VANISH trial randomized patients with previous MI and VT despite initial AAD therapy to either escalated AAD treatment or catheter ablation. VT burden was defined as the total number of VT events treated with ≥1 appropriate ICD therapy. Appropriate ICD therapy burden was defined as the total number of appropriate shocks or antitachycardia pacing therapies (ATPs) delivered. The Anderson-Gill recurrent event model was used to compare burden between the treatment arms. RESULTS: Of the 259 enrolled patients (median age, 69.8 years; 7.0% women), 132 patients were randomized to ablation and 129 patients were randomized to escalated AAD therapy. Over 23.4 months of follow-up, ablation-treated patients had a 40% lower shock-treated VT event burden and a 39% lower appropriate shock burden compared with patients who received escalated AAD therapy (P <0.05 for all). A reduction in VT burden, ATP-treated VT event burden, and appropriate ATP burden among ablation patients was only demonstrated in the stratum of patients with amiodarone-refractory VT (P <0.05 for all). CONCLUSIONS: Among patients with AAD-refractory VT and a previous MI, catheter ablation reduced shock-treated VT event burden and appropriate shock burden compared with escalated AAD therapy. There was also lower VT burden, ATP-treated VT event burden, and appropriate ATP burden among ablation-treated patients; however, the effect was limited to patients with amiodarone-refractory VT.

Air Pollution and Arrhythmias.

Air pollution is commonly defined as the contamination of the air we breathe by any chemical, physical, or biological agent that is potentially threatening to human and ecosystem health. The common pollutants known to be disease-causing are particulate matter, ground-level ozone, sulphur dioxide, nitrogen dioxide, and carbon monoxide. Although the association between increasing concentrations of these pollutants and cardiovascular disease is now accepted, the association of air pollution and arrhythmias is less well established. In this review we provide an in-depth discussion of the association of acute and chronic air pollution exposure and arrhythmia incidence, morbidity, and mortality, and the purported pathophysiological mechanisms. Increases in concentrations of air pollutants have multiple proarrhythmic mechanisms including systemic inflammation (via increases in reactive oxygen species, tumour necrosis factor, and direct effects from translocated particulate matter), structural remodelling (via an increased risk of atherosclerosis and myocardial infarction or by affecting the cell-to-cell coupling and gap junction function), and mitochondrial and autonomic dysfunction. Furthermore, we describe the associations of air pollution and arrhythmias. There is a strong correlation of acute and chronic air pollutant exposure and the incidence of atrial fibrillation. Acute increases in air pollution increase the risk of emergency room visits and hospital admissions for atrial fibrillation and the risk of stroke and mortality in patients with atrial fibrillation. Similarly, there is a strong correlation of increases of air pollutants and the risk of ventricular arrhythmias, out-of-hospital cardiac arrest, and sudden cardiac death.

Cost-effectiveness of atrial fibrillation screening in Canadian community practice.

Background: Contemporary guidelines recommend opportunistic screening for atrial fibrillation (AF). Objective: The objective of this study was to assess the cost-effectiveness of single time point opportunistic AF screening for patients 65 years and older by using the single-lead electrocardiogram. Methods: An established Markov cohort model was adapted by updating the background mortality estimates, epidemiology, screening efficacy, treatment patterns, resource use, and cost inputs to reflect a Canadian health care setting. Inputs were derived from a contemporary prospective screening study performed in Canadian primary care settings (screening efficacy and epidemiology) and the published literature (unit costs, epidemiology, mortality, utility, and treatment efficacy). The impact of screening and oral anticoagulant treatment on the cost and clinical outcomes was analyzed. A Canadian payer perspective over lifetime was used for analysis, with costs expressed in 2019 Canadian dollars. Results: Among the estimated screening-eligible population of 2,929,301 patients, the screening cohort identified an additional 127,670 AF cases compared with the usual care cohort. The model estimated avoidance of 12,236 strokes and incremental quality-adjusted life-years of 59,577 (0.02 per patient) over lifetime in the screening cohort. Cost savings were substantial because of improved health outcomes, reflecting screening being the dominant strategy (affordable and effective). Model results were robust across sensitivity and scenario analyses. Conclusion: Single time point opportunistic screening of AF using a single-lead electrocardiogram device in Canadian patients 65 years and older without known AF may provide improved health outcomes with cost savings from the perspective of a single payer health care environment.

Incidence and clinical impact of tachyarrhythmic events following transcatheter aortic valve replacement: A review.

Transcatheter aortic valve replacement (TAVR) is well established for treating severe symptomatic aortic stenosis. Whereas broad information on the epidemiology, clinical implications, and management of bradyarrhythmias after TAVR is available, data about tachyarrhythmic events remain scarce. Despite the progressively lower risk profile of TAVR patients and the improvement in device characteristics and operator skills, approximately 10% of patients develop new-onset atrial fibrillation (NOAF) after TAVR. The proportion of patients in whom NOAF actually corresponds to previously undiagnosed silent atrial fibrillation (AF) has not been properly determined. The transapical approach, the need for pre- or post- balloon dilation, and the presence of periprocedural complications have been associated with a higher risk of NOAF. Older age, left atrial volume, or worse functional class are patient-derived risk factors shared with preprocedural AF. NOAF after TAVR has been associated with poorer survival and a higher incidence of cerebrovascular events. However, patient management differs markedly among different centers, especially with regard to anticoagulation in patients with short-duration AF episodes detected in the periprocedural setting and in cases of silent NOAF detected during continuous electrocardiographic (ECG) monitoring. Evidence about ventricular arrhythmias is even more scarce than for AF. Some case reports of sudden cardiac death after TAVR in patients with a pacemaker have identified ventricular tachycardia or ventricular fibrillation in device interrogation. TAVR has been shown to reduce the arrhythmic burden, but a significant proportion of patients (16%) present with complex premature ventricular complex arrhythmias within the year after TAVR. Whether these events are related to poorer outcomes is unknown. Continuous ECG monitoring after TAVR may help describe the frequency, risk factors, and prognostic implications of tachyarrhythmias in this population.

Characterization of arrhythmia substrate to ablate persistent atrial fibrillation (COAST-AF): Randomized controlled trial design and rationale.

BACKGROUND: Atrial low voltage area (LVA) catheter ablation has emerged as a promising strategy for ablation of persistent atrial fibrillation (AF). It is unclear if catheter ablation of atrial LVA increases treatment success rates in patients with persistent AF. OBJECTIVE: The primary aim of this trial is to assess the potential benefit of adjunctive catheter ablation of atrial LVA in addition to pulmonary vein isolation (PVI) in patients with persistent AF, when compared to PVI alone. The secondary aims are to evaluate safety outcomes, the quality of life and the healthcare resource utilization. METHODS/DESIGN: A multicenter, prospective, parallel-group, 2-arm, single-blinded randomized controlled trial is under way (NCT03347227). Patients who are candidates for catheter ablation for persistent AF will be randomly assigned (1:1) to either PVI alone or PVI + atrial LVA ablation. The primary outcome is 18-month documented event rate of atrial arrhythmia (AF, atrial tachycardia or atrial flutter) post catheter ablation. Secondary outcomes include procedure-related complications, freedom from atrial arrhythmia at 12 months, AF burden, need for emergency department visits/hospitalization, need for repeat ablation for atrial arrhythmia, quality of life at 12 and 18 months, ablation time, and procedure duration. DISCUSSION: Characterization of Arrhythmia Mechanism to Ablate Atrial Fibrillation (COAST-AF) is a multicenter randomized trial evaluating ablation strategies for catheter ablation. We hypothesize that catheter ablation of atrial LVA in addition to PVI will result in higher procedural success rates when compared to PVI alone in patients with persistent AF.

Safety of Cefazolin Test Dose in Patients With Penicillin Allergy Just Prior to Cardiac Device Implantation: A Single-Centre Experience.

Background: Cephalosporins are the cornerstone of cardiac device infection prophylaxis. Owing to fears of cross-reactivity, penicillin-allergic patients are exposed to potentially more-toxic drugs, with decreased efficacy. We evaluated the safety of a cefazolin test dose (CTD) in self-reported penicillin-allergic patients. Methods: In this single-centre study, we evaluated consecutive patients with chart documentation of penicillin allergy undergoing cardiac device implantation, over a 2-year period. A CTD was performed if no cephalosporin allergy or severe anaphylactic reaction to penicillin had been documented. Patients were given 2 doses of 100 mg IV cefazolin, and if no allergic reaction occurred after 5 minutes, the full dose (1800 mg) was administered in the electrophysiology laboratory just before the implantation procedure. Results: A total of 2200 patients were included. The frequency of reported penicillin allergy was 9.3% (n = 204). In 80% of cases, the type of allergic reaction was not reported in medical notes or was unknown by the patient. A CTD was performed in 67.6% of patients with a penicillin allergy (n = 138). A total of 5 adverse events occurred (3.6% of patients [95% confidence interval, 1.1%-6.1%]) - 4 skin rashes and 1 tongue edema. These 5 patients became asymptomatic after antihistaminic and corticosteroid IV treatment. Even if the test dose was negative, 79% of patients also were administered vancomycin before the procedure, as it requires a 1-hour infusion prior to the CTD in the implantation procedure room. Conclusion: A CTD in most penicillin-allergic patients appears to be safe and allows its use per recommended guidelines.

Contexte: Les céphalosporines sont la pierre angulaire de la prophylaxie des infections des dispositifs cardiaques. En raison du risque appréhendé de réactivité croisée, les patients allergiques à la pénicilline se trouvent exposés à des médicaments potentiellement plus toxiques, qui s'avèrent aussi moins efficaces. Nous avons évalué l'innocuité d'une dose d'essai de céfazoline chez des patients qui s'étaient dits allergiques à la pénicilline. Méthodologie: Dans cette étude monocentrique, nous avons suivi pendant deux ans des patients consécutifs dont le dossier médical faisait état d'une allergie à la pénicilline et chez qui un dispositif cardiaque devait être implanté. Une dose d'essai de céfazoline a été administrée aux patients sans antécédents documentés d'allergie aux céphalosporines ou de réaction anaphylactique sévère à la pénicilline. Deux doses de 100 mg de céfazoline ont été administrées par voie intraveineuse. En l'absence de réaction allergique après cinq minutes, les patients recevaient la dose complète (1 800 mg) au laboratoire d'électrophysiologie juste avant l'implantation du dispositif cardiaque. Résultats: Au total, 2 200 patients ont été inscrits à l'étude. Le taux de signalement de l'allergie à la pénicilline était de 9,3 % (n = 204). Dans 80 % des cas, le type de réaction allergique n'a pas été précisé dans les notes médicales ou était inconnu du patient. Une dose d'essai de céfazoline a été administrée à 67,6 % des patients allergiques à la pénicilline (n = 138). Au total, cinq événements indésirables se sont produits (3,6 % des patients [intervalle de confiance à 95 % : 1,1-6,1 %]) ­ quatre éruptions cutanées et un œdème de la langue. Les cinq patients touchés par ces événements sont devenus asymptomatiques après avoir reçu un antihistaminique et un corticostéroïde par voie intraveineuse. Même en l'absence de réaction allergique à la dose d'essai, 79 % des patients ont reçu de la vancomycine avant l'intervention, cet agent devant être administré par perfusion durant une heure avant la dose d'essai de céfazoline dans la salle d'intervention. Conclusion: Chez la plupart des patients allergiques à la pénicilline, une dose d'essai de céfazoline semble sans danger et permet d'avoir recours à ce médicament conformément aux lignes directrices.

Ablation of Refractory Ventricular Tachycardia Using Intramyocardial Needle Delivered Heated Saline-Enhanced Radiofrequency Energy: A First-in-Man Feasibility Trial.

BACKGROUND: Ablation of ventricular tachycardia (VT) is limited by the inability to create penetrating lesions to reach intramyocardial origins. Intramural needle ablation using in-catheter, heated saline-enhanced radio frequency (SERF) energy uses convective heating to increase heat transfer and produce deeper, controllable lesions at intramural targets. This first-in-human trial was designed to evaluate the safety and efficacy of SERF needle ablation in patients with refractory VT. METHODS: Thirty-two subjects from 6 centers underwent needle electrode ablation. Each had recurrent drug-refractory monomorphic VT after implantable cardioverter defibrillator implantation and prior standard ablation. During the SERF study procedure, one or more VTs were induced and mapped. The SERF needle catheter was used to create intramural lesions at targeted VT site(s). Acute procedural success was defined as noninducibility of the clinical VT after the procedure. Patients underwent follow-up at 30 days, and 3 and 6 months, with implantable cardioverter defibrillator interrogation at follow-up to determine VT recurrence. RESULTS: These refractory VT patients (91% male, 66±10 years, ejection fraction 35±11%; 56% ischemic, and 44% nonischemic) had a median of 45 device therapies (shock/antitachycardia pacing) for VT in the 3 to 6 months pre-SERF ablation. The study catheter was used to deliver an average of 10±5 lesions per case, with an average of 430±295 seconds of radiofrequency time, 122±65 minute of catheter use time, and a procedural duration of 4.3±1.3 hours. Acute procedural success was 97% for eliminating the clinical VT. At average follow-up of 5 months (n=32), device therapies were reduced by 89%. Complications included 2 periprocedural deaths: an embolic mesenteric infarct and cardiogenic shock, 2 mild strokes, and a pericardial effusion treated with pericardiocentesis (n=1). CONCLUSIONS: Intramural heated saline needle ablation showed complete acute and satisfactory mid-term control of difficult VTs failing 1 to 5 prior ablations and drug therapy. Further study is warranted to define safety and longer-term efficacy. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique Identifier: NCT03628534 and NCT02994446.

Evaluation of Saline-Enhanced Radiofrequency Needle-Tip Ablation for Ventricular Tachycardia (SERF VT CANADA Trial).

BACKGROUND: Endocardial catheter ablation for ventricular tachycardia (VT) may fail owing to the inability to deliver transmural lesions. Saline-enhanced radiofrequency (SERF) ablation uses a needle-tip catheter that is placed at varying depths into the myocardial tissue and heated saline solution is injected along with radiofrequency power (RF), creating fully transmural lesions. We report the first in-human SERF ablation for VT in Canada. METHODS: Twenty-five patients with ischemic and nonischemic cardiomyopathy, with recurrent monomorphic drug-refractory VT who had failed a prior catheter ablation underwent SERF ablation in 3 different centres in Canada. After a voltage map, the mapping catheter was replaced with the needle-tipped ablation catheter, which was located perpendicular to the myocardium and extended either 6 or 8 mm into the tissue. Sterile saline solution was infused at a flow rate of 10 mL/min and at 60 °C, and 20-50 W RF was used. RESULTS: Baseline left ventricular ejection fraction was 33.3 ± 8.6%, mean age was 69.5 ± 6.4 years; 92% were male. From 43 clinical VTs induced, 42 were ablated and 266 SERF lesions were delivered (10.6 ± 4.9 per patient). Of the 42 treated clinical VTs, 41 VTs (98%) were noninducible and 24 patients (96%) had their VT eliminated. At 6 months' follow-up, 42% of patients were free from VT and there was a 73% reduction in shocks. CONCLUSIONS: SERF ablation is feasible and permits control of symptomatic monomorphic VT in drug-refractory patients with a prior failed ablation.

Evolution of Devices to Prevent Sudden Cardiac Death: Contemporary Clinical Impacts.

Implantable cardioverter defibrillators (ICDs) are recommended for primary and secondary prevention of sudden cardiac death and were first implanted more than 40 years ago. The addition of cardiac resynchronization improved outcomes in the heart failure population and is now an important part of optimized therapy for this population. In this review, we will address patient selection, risk stratification, and outcomes after ICD placement and technological improvements. Gender disparities in referral and outcomes will be discussed. Far from early technologies with limited pacing capabilities and no antitachycardia pacing (ATP), we have now moved to complex devices with the addition of ATP/ATP during charging, cardiac resynchronization therapy, remote monitoring, and improved battery longevity. The requirement for defibrillation testing at time of implantation has changed and in most implants are not required as part of new clinical guidelines. As the components most likely to fail are the leads, and many complications arise from the intravascular components, extravascular ICDs were developed, the subcutaneous ICD is now an option for many patients, and substernal devices are under clinical trials. Because shocks are associated with worse outcomes, optimized ICD programming is now recommended, with the benefit of reducing appropriate and inappropriate shocks with a decrease in mortality and no increase in the syncopal events. All these improvements will have a positive effect on patient outcomes and quality of life, and new technologies will be developed in the future.

Ventricular tachycardia characteristics and outcomes with catheter ablation vs. antiarrhythmic therapy: insights from the VANISH trial.

AIMS: Catheter ablation is superior to escalated antiarrhythmic drugs among patients with ventricular tachycardia (VT) and prior myocardial infarction (MI). However, it is uncertain whether clinical VT characteristics, should influence choice of therapy. The purpose of this study was to evaluate whether presentation with electrical storm and the clinical VT cycle length predicted response to ablation vs. escalated antiarrhythmic therapy. METHODS AND RESULTS: All patients enrolled in the Ventricular Tachycardia Ablation vs. Escalated Antiarrhythmic Drug Therapy in Ischaemic Heart Disease (VANISH) trial were included. The association between VT cycle length and presentation with electrical storm and the primary outcome of death, subsequent VT storm or appropriate ICD shock was evaluated. Among the study population of 259 patients, escalated antiarrhythmic drug therapy had worse outcomes for those presenting with a VT cycle length >400 ms [<150 b.p.m., 89/259, hazard ratio (HR) 1.7 (1.02-3.13)]. This effect was more pronounced among those taking amiodarone at baseline [HR of 2.22 (1.19-4.16)]. Presentation with VT storm (32/259) did not affect the primary outcome between groups. However, those presenting with VT storm on amiodarone had a trend towards worse outcomes with escalated antiarrhythmic therapy [HR 4.31 (0.55-33.93)]. CONCLUSION: The VT cycle length can influence response to either ablation or escalated drug therapy in patients with VT and prior MI. Those with slow VT had improved outcomes with ablation. Patients presenting with electrical storm demonstrated similar outcomes to the overall trial population, with a trend to benefit of catheter ablation, particularly in those on amiodarone.