A left atrial appendage closure combined procedure review: Past, present, and future perspectives.

BACKGROUND AND OBJECTIVE: Atrial fibrillation (AF) represents the most common cardiac arrhythmia worldwide; it poses a great burden in terms of quality of life reduction and yearly stroke risk. Left atrial appendage closure (LAAC) is a stroke prevention strategy that has been proven a viable alternative to antithrombotic regimens in nonvalvular AF patients. LAAC can be performed as a standalone procedure or alongside a concomitant AF transcatheter ablation, in a procedure known as "Combined procedure". Aim of this study is to summarize the scientific evidence backing this combined strategy. METHODS: We reviewed the whole Medline indexed combined procedure literature, to summarize all the combined procedure study data. RESULTS: Nine published studies regarding combined procedure were found. Data, aims, and scientific rationales were reported and commented. CONCLUSION: LAA combined procedure appears to be a safe and effective procedure; a careful patient selection is necessary to maximize its benefit.

Acute outcome after a single cryoballoon ablation: Comparison between Arctic Front Advance and Arctic Front Advance PRO.

BACKGROUND: The novel fourth-generation cryoballoon (CB4) potentially allows for enhanced catheter maneuverability and more frequent capture of pulmonary vein (PV) potentials which can be used to monitor real-time PV isolation (PVI). The aim of our study is to compare the acute procedural endpoints between the CB4 and second-generation cryoballoon (CB2). METHODS: A single-center retrospective chart review was used to examine 50 consecutive patients with drug-refractory atrial fibrillation undergoing CB4-based PVI. Procedural data and acute success of these patients were compared to 50 propensity-matched controls who underwent cryoballoon ablation procedure using CB2. RESULTS: Procedures performed with the CB4 showed significant shorter fluoroscopy time (14.8 ± 5.5 vs 18.0 ± 6.5 minutes, P = .04), shorter procedure time (58.3 ± 15.7 vs 65.3 ± 21 minutes, P = .13), and shorter total ablation time (10.8 ± 1.5 vs 13.8 ± 1.9 minutes, P = .42). The real-time PVI visualization rate was 33.3% in the CB2 group and 74.7% in the CB4 group (P < .001). CB4 was correlated to significant increase of acute real-time recordings with regard to all the single PV (left superior PV: 58% vs 84%, P = .02; left inferior PV: 26% vs 71%, P = .001; right superior PV 29% vs 61%, P = .01; and right inferior PV 19% vs 58%, P = .002). CONCLUSION: The CB4 was more often able to capture real-time recordings of PV potentials and the subsequent acute PV isolation.

Concomitant cryoballoon ablation and percutaneous closure of left atrial appendage in patients with atrial fibrillation.

AIMS: Pulmonary veins (PVs) isolation is the cornerstone of atrial fibrillation (AF) ablation and can be achieved either by conventional radiofrequency ablation or by cryoenergy. Left atrial appendage (LAA) closure has been proposed as alternative treatment to vitamin K antagonists (VKA). We aimed to evaluate the feasibility of combining cryoballoon (CB) ablation and LAA occlusion in patients with AF and a high thromboembolic risk or contraindication to antithrombotic therapy. METHODS AND RESULTS: Thirty-five patients (28 males, 74 ± 2 years) underwent CB ablation. Left atrial appendage occlusion was carried out by using two occluder devices (Amplatz Cardiac Plug, ACP, St. Jude Medical, MN, USA, in 25 patients; Watchman, Boston Scientific, MA, USA, in 10 patients). Thirty patients (86%) had previous stroke/TIA episodes, 6 patients (17%) had major bleeding while on VKA therapy, and 7 patients (20%) had inherited bleeding disorders. Over the follow-up (24 ± 12 months), atrial arrhythmias recurred in 10 (28%) patients. Thirty patients (86%) had complete sealing; 5 patients (14%) showed a residual flow (<5 mm) at first transoesophageal echocardiography (TEE) check, while at 1-year TEE residual flow was detected in 3 patients. In 13 patients (37%), VKA therapy was immediately discontinued. Six patients (17%) received novel oral anticoagulants treatment and then discontinued 3 months thereafter. No device-related complications or clinical thromboembolic events occurred. CONCLUSION: Combined CB ablation and LAA closure using different devices appears to be feasible in patients with non-valvular AF associated with high risk of stroke or contraindication to antithrombotic treatment.

Near zerO fluoroscopic exPosure during catheter ablAtion of supRavenTricular arrhYthmias: the NO-PARTY multicentre randomized trial.

AIMS: Aim of this study was to compare a minimally fluoroscopic radiofrequency catheter ablation with conventional fluoroscopy-guided ablation for supraventricular tachycardias (SVTs) in terms of ionizing radiation exposure for patient and operator and to estimate patients' lifetime attributable risks associated with such exposure. METHODS AND RESULTS: We performed a prospective, multicentre, randomized controlled trial in six electrophysiology (EP) laboratories in Italy. A total of 262 patients undergoing EP studies for SVT were randomized to perform a minimally fluoroscopic approach (MFA) procedure with the EnSiteTMNavXTM navigation system or a conventional approach (ConvA) procedure. The MFA was associated with a significant reduction in patients' radiation dose (0 mSv, iqr 0-0.08 vs. 8.87 mSv, iqr 3.67-22.01; P < 0.00001), total fluoroscopy time (0 s, iqr 0-12 vs. 859 s, iqr 545-1346; P < 0.00001), and operator radiation dose (1.55 vs. 25.33 µS per procedure; P < 0.001). In the MFA group, X-ray was not used at all in 72% (96/134) of cases. The acute success and complication rates were not different between the two groups (P = ns). The reduction in patients' exposure shows a 96% reduction in the estimated risks of cancer incidence and mortality and an important reduction in estimated years of life lost and years of life affected. Based on economic considerations, the benefits of MFA for patients and professionals are likely to justify its additional costs. CONCLUSION: This is the first multicentre randomized trial showing that a MFA in the ablation of SVTs dramatically reduces patients' exposure, risks of cancer incidence and mortality, and years of life affected and lost, keeping safety and efficacy. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01132274.

Validation of manual to complement the transition of care at discharge from intensive care.

OBJECTIVE: To develop and validate an interprofessional manual for the transfer of care to critically ill adult patients. METHOD: Methodological study, conducted from January to September 2019. The content of the manual was listed by the multidisciplinary team of an adult Intensive Care Unit, in southern Brazil. In the validation by the professionals, the content validity index (CVI) of the evaluation questions was calculated. Subsequently, a sample of 30 patients/caregivers evaluated the product, and the arithmetic mean of the questions was calculated. RESULTS: The manual addresses important information and care transition guidance for patients and caregivers, from admission to the intensive care to discharge to the inpatient unit. The professionals' CVI ranged from 0.9 to 1. The arithmetic mean of 17 patients and 13 caregivers was 3.8. FINAL CONSIDERATIONS: The validated manual can be used as a complementary material for health education and qualify the transition of care.

Long-Term Outcomes of Near-Zero Radiation Ablation of Paroxysmal Supraventricular Tachycardia: A Comparison With Fluoroscopy-Guided Approach.

OBJECTIVES: This study aimed to assess the long-term outcomes of minimally fluoroscopic approach (MFA) compared with conventional fluoroscopic ablation (ConvA) in terms of recurrences of arrhythmia and long-term complications. BACKGROUND: Catheter ablation (CA) of supraventricular tachycardia (SVT) with an MFA, under the guidance of electroanatomic mapping (EAM) systems, results in a significant reduction in exposure to ionizing radiations without impairing acute procedural success and complication rate. However, data regarding long-term outcomes of MFA compared with ConvA are lacking. METHODS: This is a retrospective observational study. All patients undergoing MFA CA of SVT (atrioventricular nodal re-entrant tachycardia and atrioventricular re-entrant tachycardia) between 2010 and 2015 were enrolled and were compared with matched subjects (1 MFA: 2 ConvA) undergoing ConvA during the same period. The 2 co-primary outcomes were recurrence of arrhythmias and long-term complications. RESULTS: A total of 618 patients (mean age 38 ± 15 years, 60% female) were enrolled. MFA included 206 patients, whereas 412 were treated with ConvA. Acute success (99% vs. 97%; p = 0.10) and acute complications (2.4% vs. 5.3%; p = 0.14) were similar in the 2 groups. During a median follow-up of 4.4 years, 5.9% of patients experienced recurrence of arrhythmias. At multivariate analysis, ConvA (hazard ratio [HR]: 3.03) and procedural success (HR: 0.10) were independently associated with recurrence of arrhythmias. Late complications (i.e., advance atrioventricular block and need for pacemaker implantation) occurred more frequently in ConvA (3.4% vs. 0.5%; p = 0.03) compared with MFA. CONCLUSIONS: CA guided by EAM systems with MFA provided better long-term results and reduced risk of complications compared with ConvA.

An ablation index operator-independent approach to improve efficacy in atrial fibrillation ablation at 24-month follow-up: a single center experience.

PURPOSE: Since the introduction of catheter ablation as a mainstream treatment for atrial fibrillation (AF), several technical improvements have been put forward. In this contest, Ablation Index (AI) is an accurate ablation quality marker by incorporating power, delivery time, contact force (CF), and catheter stability in a weighted formula. The aim of our study is to evaluate the efficacy of AI-guided AF ablation over 24 month follow-up. METHODS: We evaluated 72 consecutive patients with drug-refractory paroxysmal (66.7%) and early-persistent AF (33.3%) undergoing AI-guided ablation, compared to 72 propensity-matched control patients who underwent CF-guided procedure. All procedures were performed by three skilled operators. Data concerning procedural characteristics and long-term freedom from AF recurrence were analyzed. RESULTS: At 24-month follow-up, Kaplan-Meier curves of AF recurrence were significantly lower in AI group than in CF group (15.5% vs. 30.6%; p 0.042). These findings were confirmed in a sub analysis regardless of the continued use of antiarrhythmic drugs in the follow-up (42.2% in AI-guided group and 66.7% in CF-guided group, p 0.004). At 24-month follow-up, a positive trend in the decrease of arrhythmia recurrences was observed in AI-guided ablation for all operators. CONCLUSIONS: AI-guided ablation results more effective than CF-guided ablation as demonstrated by a lower incidence of AF recurrences regardless of the use of antiarrhythmic drugs in the follow-up. Each operator seems to improve the long-term success using an AI-guided ablation, thus showing both the efficacy and the reproducibility of this approach.

Lesion index: a novel guide in the path of successful pulmonary vein isolation.

PURPOSE: Previous studies indicate force time integral (FTI) as a radiofrequency (RF) lesion quality marker, while not considering power supply. Tacticath™ Quartz catheter provides Lesion index (LSI), a lesion quality marker derived by contact force (CF), power supply, and RF time combined. Our aim is to assess LSI and FTI correlation and a LSI-related cutoff of atrial fibrillation (AF) recurrences 12 months after pulmonary vein isolation (PVI). METHODS: We retrospectively enrolled 37 patients who underwent RF ablation using Tacticath™ Quartz catheter. AF recurrence rate was evaluated 3, 6, and 12 months after PVI procedure. RESULTS: AF recurrence was detected in 32% of patients. FTI mean value was significantly lower in left superior pulmonary vein (LSPV: 256 ± 86 gs vs 329 ± 117 gs, p = 0.05) and right inferior pulmonary vein (RIPV: 253 ± 128 gs vs 394 ± 123 gs p = 0.006) in patients with AF recurrences; no significant differences were found in right superior pulmonary vein (RSPV) and left inferior pulmonary vein (LIPV). LSI instead was significantly higher for all veins in patients without AF recurrences: LSPV (5.2 ± 0.7 vs 4.6 ± 0.8, p = 0.03), LIPV (5.0 ± 0.8 vs 4.5 ± 0.6, p = 0.04), RSPV (5.5 ± 0.6 vs 5.1 ± 0.6, p = 0.05), and RIPV (5.5 ± 0.7 vs 4.7 ± 0.8, p = 0.006). Receiver operator characteristic curve suggests 5.3 as LSI overall cutoff value predicting freedom from disease at 1-year follow-up. CONCLUSIONS: Our preliminary data suggest that a LSI mean value higher than 5.3 can be considered a good predictor of AF freedom at 1-year follow-up.

X-Ray Exposure in Cardiac Electrophysiology: A Retrospective Analysis in 8150 Patients Over 7 Years of Activity in a Modern, Large-Volume Laboratory.

BACKGROUND: Only a few studies have systematically evaluated fluoroscopy data of electrophysiological and device implantation procedures. Aims of this study were to quantify ionizing radiation exposure for electrophysiological/device implantation procedures in a large series of patients and to analyze the x-ray exposure trend over years and radiation exposure in patients undergoing atrial fibrillation ablation considering different technical aspects. METHODS AND RESULTS: We performed a retrospective analysis of all electrophysiological/device implantation procedures performed during the past 7 years in a modern, large-volume laboratory. We reported complete fluoroscopy data on 8150 electrophysiological/device implantation procedures (6095 electrophysiological and 2055 device implantation procedures); for each type of procedure, effective dose and lifetime attributable risk of cancer incidence and mortality were calculated. Over the 7-year period, we observed a significant trend reduction in fluoroscopy time, dose area product, and effective dose for all electrophysiological procedures (P<0.001) and a not statistically significant trend reduction for device implantation procedures. Analyzing 2416 atrial fibrillation ablations, we observed a significant variability of fluoroscopy time, dose area product and effective dose among 7 different experienced operators (P<0.0001) and a significant reduction of fluoroscopy use over time (P<0.0001) for all of them. Considering atrial fibrillation ablation techniques, fluoroscopy time was not different (P = 0.74) for radiofrequency catheter ablation in comparison with cryoablation, though cryoablation was still associated with higher dose area product and effective dose values (P<0.001). CONCLUSIONS: Electrophysiological procedures involve a nonnegligible x-ray use, leading to an increased risk of malignancy. Awareness of radiation-related risk, together with technological advances, can successfully optimize fluoroscopy use.

Validation of manual to complement the transition of care at discharge from intensive care / Validación del manual para complementar la transición de cuidados al alta de cuidados intensivos / Validação de manual para complementar a transição de cuidados na alta da terapia intensiva

ABSTRACT Objective To develop and validate an interprofessional manual for the transfer of care to critically ill adult patients. Method Methodological study, conducted from January to September 2019. The content of the manual was listed by the multidisciplinary team of an adult Intensive Care Unit, in southern Brazil. In the validation by the professionals, the content validity index (CVI) of the evaluation questions was calculated. Subsequently, a sample of 30 patients/caregivers evaluated the product, and the arithmetic mean of the questions was calculated. Results The manual addresses important information and care transition guidance for patients and caregivers, from admission to the intensive care to discharge to the inpatient unit. The professionals' CVI ranged from 0.9 to 1. The arithmetic mean of 17 patients and 13 caregivers was 3.8. Final considerations The validated manual can be used as a complementary material for health education and qualify the transition of care.

RESUMEN Objetivo Desarrollar y validar un manual interprofesional para la transferencia del cuidado al paciente adulto crítico. Método Estudio metodológico, realizado de enero a septiembre/2019. El contenido del manual fue listado por el equipo multidisciplinario de un Centro de Cuidados Intensivos de adultos, en el Sur de Brasil. En la validación por los profesionales se calculó el índice de validez de contenido (IVC) de las preguntas de evaluación. Posteriormente, una muestra de 30 pacientes/cuidadores evaluó el producto, y se calculó la media aritmética de las preguntas. Resultados El manual aborda información importante y orientaciones de transición asistencial para pacientes y cuidadores desde el ingreso a los cuidados intensivos hasta el alta a la unidad de hospitalización. El CVI de los profesionales varió de 0,9 a 1. La media aritmética de 17 pacientes y 13 cuidadores fue de 3,8. Consideraciones finales El manual validado puede ser utilizado como material complementario para la educación en salud y la calificación de la transición de cuidados.

RESUMO Objetivo Desenvolver e validar um manual interprofissional de transferência de cuidados ao paciente adulto crítico. Método Estudo metodológico, realizado de janeiro a setembro/2019. O conteúdo do manual foi elencado pela equipe multiprofissional de um Centro Terapia Intensiva adulto, do Sul do Brasil. Na validação pelos profissionais, foi calculado o índice de validade de conteúdo (IVC) das questões de avaliação. Posteriormente, amostra de 30 pacientes/cuidadores avaliou o produto, sendo calculada a média aritmética das questões. Resultados O manual aborda informações importantes e orientações de transição do cuidado, para pacientes e cuidadores, desde a admissão na terapia intensiva até a alta para unidade de internação. O IVC dos profissionais variou de 0,9 a 1. A média aritmética, de 17 pacientes e 13 cuidadores foi 3,8. Considerações finais O manual validado poderá ser utilizado como material complementar de educação em saúde e qualificar a transição de cuidados.

Difficult case of a trans-septal puncture: Use of a "SafeSept" guidewire.

A 69-year-old man was admitted to our center to undergo catheter ablation of paroxysmal atrial fibrillation refractory to antiarrhythmic drug therapy. This procedure required access to the left atrium through the interatrial septum. During hospitalization, the patient performed routinely pre-procedure transthoracic echocardiography and gadolinium-enhanced cardiac magnetic resonance showing a normal anatomy of both the fossa ovalis and the interatrial septum. Access to the left atrium proved difficult and several unsuccessful attempts to perform the trans-septal puncture were made under both fluoroscopy and intracardiac echocardiography guidance, even with radiofrequency energy delivery. Finally, trans-septal puncture was successfully carried out using a novel nitinol J-shaped "SafeSept" trans-septal guidewire, designed to cross the interatrial septum through the trans-septal needle thanks to a special sharp tip. Moreover, thanks to its rounded J shape that reduces the risk of atrial perforation, the "SafeSept" guidewire, when advanced into the left atrium, becomes atraumatic.

Idiopathic Ventricular Tachycardia: Transcatheter Ablation or Antiarrhythmic Drugs?

INTRODUCTION: Ventricular tachycardia or frequent premature ventricular contractions (PVCs) can occur in the absence of any detectable structural heart disease. In this clinical setting, these arrhythmias are termed idiopathic. Usually, they carry a benign prognosis and any potential ablative intervention is carried out if patients are highly symptomatic or, more importantly, if frequent ventricular arrhythmias can lead to ventricular dysfunction. METHODS: In this paper, different forms of idiopathic ventricular tachycardia are reviewed. Outflow tract ventricular tachycardia from the right ventricle is the most frequent form of the so-called idiopathic ventricular tachycardia. Other forms of idiopathic ventricular arrhythmias include ventricular tachycardia/PVCs arising from tricuspid annulus, from the mitral annulus, inter-fascicular ventricular tachycardia and papillary muscle ventricular tachycardia. When interventional treatment is deemed necessary, detailed mapping ( earliest activation during VT/PVC, pace mapping ) is crucial as to identify the successful ablation site. Catheter ablation more than antiarrhythmic drug treatment is usually highly effective in eliminating idiopathic ventricular arrhythmias and providing prevention of recurrence. CONCLUSIONS: Idiopathic VTs are not considered life-threatening arrhythmias and, prevention of recurrences is often achieved by means of catheter ablation that provides an improvement of quality of life. The overall acute success rate of catheter ablation is about 85-90% with a long-term prevention of arrhythmia recurrence of about 75-80%. It is advisable that the procedure is carried out by electrophysiologists with expertise in VT catheter ablation and extensive knowledge of cardiac anatomy as to ensure a high success rate and reduce the likelihood of major complications.

Electrical storm: A clinical and electrophysiological overview.

Electrical storm (ES) is a clinical condition characterized by three or more ventricular arrhythmia episodes leading to appropriate implantable cardioverter-defibrillator (ICD) therapies in a 24 h period. Mostly, arrhythmias responsible of ES are multiple morphologies of monomorphic ventricular tachycardia (VT), but polymorphic VT and ventricular fibrillation can also result in ES. Clinical presentation is very dramatic in most cases, strictly related to the cardiac disease that may worsen electrical and hemodynamic decompensation. Therefore ES management is challenging in the majority of cases and a high mortality is the rule both in the acute and in the long-term phases. Different underlying cardiomyopathies provide significant clues into the mechanism of ES, which can arise in the setting of structural arrhythmogenic cardiomyopathies or rarely in patients with inherited arrhythmic syndrome, impacting on pharmacological treatment, on ICD programming, and on the opportunity to apply strategies of catheter ablation. This latter has become a pivotal form of treatment due to its high efficacy in modifying the arrhythmogenic substrate and in achieving rhythm stability, aiming at reducing recurrences of ventricular arrhythmia and at improving overall survival. In this review, the most relevant epidemiological and clinical aspects of ES, with regard to the acute and long-term follow-up implications, were evaluated, focusing on these novel therapeutic strategies of treatment.

Right Ventricular Outflow Tract Arrhythmias: Benign Or Early Stage Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia?

Ventricular arrhythmias (VAs) arising from the right ventricular outflow tract (RVOT) are a common and heterogeneous entity. Idiopathic right ventricular arrhythmias (IdioVAs) are generally benign, with excellent ablation outcomes and long-term arrhythmia-free survival, and must be distinguished from other conditions associated with VAs arising from the right ventricle: the differential diagnosis with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is therefore crucial because VAs are one of the most important causes of sudden cardiac death (SCD) in young individuals even with early stage of the disease. Radiofrequency catheter ablation (RFCA) is a current option for the treatment of VAs but important differences must be considered in terms of indication, purposes and procedural strategies in the treatment of the two conditions. In this review, we comprehensively discuss clinical and electrophysiological features, diagnostic and therapeutic techniques in a compared analysis of these two entities.

Simultaneous assessment of contact pressure and local electrical coupling index using robotic navigation.

PURPOSE: Contact with cardiac tissue is a determinant of lesion efficacy during atrial fibrillation (AF) ablation. The Sensei®X Robotic Catheter System (Hansen Medical, CA) has been validated for contact force sensing. The electrical coupling index (ECI) from the EnSite Contact™ system (St. Jude Medical, MN) has been validated as an indicator of tissue contact. We aimed at analyzing ECI behavior during radiofrequency (RF) pulses maintaining a stable contact through the robotic navigation contact system. METHODS: In 15 patients (age, 59 ± 12) undergoing AF ablation, pulmonary vein (PV) isolation was guided by the Sensei®X System, employing the Contact™ catheter. RESULTS: During the procedure, we assessed ECI changes associated with adequate contact based on the IntelliSense® force-sensing technology (Hansen Medical, CA. Baseline contact (27 ± 8 g/cm(2)) ECI value was 99 ± 13, whereas ECI values in a noncontact site (0 g/cm(2)) and in a light contact site (1-10 g/cm(2)) were respectively 66 ± 12 and 77 ± 10 (p < 0.0001). Baseline contact ECI values were not different depending on AF presentation (paroxysmal AF, 98 ± 9; persistent AF, 100 ± 9) or on cardiac rhythm (sinus rhythm, 97 ± 7; AF,101 ± 10). In all PVs, ECI was significantly reduced during and after ablation (ECI during RF, 56 ± 15; ECI after RF, 72 ± 16; p < 0.001). A mean reduction of 32.2% during RF delivery and 25.4% immediately after RF discontinuation compared with baseline ECI was observed. CONCLUSIONS: Successful PV isolation is associated with a significant decrease in ECI of at least 20 %. This may be used as a surrogate marker of effective lesion in AF ablation.

New Imaging Technologies To Characterize Arrhythmic Substrate.

The cornerstone of the new imaging technologies to treat complex arrhythmias is the electroanatomic (EAM) mapping. It is based on tissue characterization and in particular on determination of low potential region and dense scar definition. Recently, the identification of fractionated isolated late potentials increased the specificity of the information derived from EAM. In addition, non-invasive tools and their integration with EAM, such as cardiac magnetic resonance imaging and computed tomography scanning, have been shown to be helpful to characterize the arrhythmic substrate and to guide the mapping and the ablation. Finally, intracardiac echocardiography, known to be useful for several practical uses in the setting of electrophysiological procedures, it has been also demonstrated to provide important informations about the anatomical substrate and may have potential to identify areas of scarred myocardium.

The Growing Culture Of A Minimally Fluoroscopic Approach In Electrophysiology Lab.

Most of interventional procedures in cardiology are carried out under fluoroscopic imaging guidance. Besides other peri-interventional risks, radiation exposure should be considered for its stochastic (inducing malignancy) and deterministic effects on health (tissue reactions like erythema, hair loss and cataracts). In this article we analized the radiation risk from cardiovascular imaging to both patients and medical staff and discusses how customize the X-ray system and how to implement shielding measures in the cath lab. Finally, we reviewed the most recent developments and the latest findings in catheter navigation and 3D electronatomical mapping systems that may help to reduce patient and operator exposure.

High-density substrate-guided ventricular tachycardia ablation: role of activation mapping in an attempt to improve procedural effectiveness.

BACKGROUND: Advanced techniques of electroanatomical mapping efficiently guide ventricular tachycardia (VT) ablation strategies; in this context, the adjunctive value of combining activation mapping (AMap) to improve accuracy has not been elucidated. OBJECTIVE: To investigate whether conventional AMap further contributes to the identification of critical sites of VT reentry and whether this translates into a more effective ablation outcome in a cohort of patients undergoing VT ablation. METHODS: We prospectively enrolled 126 patients (mean age 65.3 ± 10.5 years; left ventricular ejection fraction 33.3% ± 7.2%) with ischemic (n = 89) or idiopathic (n = 37) dilated cardiomyopathy undergoing endocardial (n = 105) or endo-epicardial (n = 21) electroanatomical mapping and ablation. A substrate-guided strategy targeting surrogate markers of reentry was accomplished in all patients, but the feasibility and efficacy of AMap was preliminarily assessed for all induced VTs focusing on early VT suppression obtained during radiofrequency delivery. VT-free survival was assessed by ICD interrogation. RESULTS: AMap successfully guided ablation in 62 of 104 (59.6%) patients with inducible VT(s). At 1 year, 6 of 126 (4.8%) patients died; VT recurred in 28 of 126 (22.2%) patients. No significant difference in VT recurrence rate was observed between patients in whom AMap proved effective versus those in whom substrate-guided ablation was not corroborated by AMap (16 of 62 [25.8%] vs 12 of 64 [18.8%]; log-rank test, P = .3). CONCLUSIONS: Our findings support the efficacy of a substrate-guided strategy targeting specific markers of arrhythmogenicity identified during sinus rhythm. AMap proves highly efficient acutely but does not improve overall VT-free survival, suggesting that in patients with advanced cardiac disease, life-threatening arrhythmias can be successfully treated by ablation in sinus rhythm, thus limiting procedural risks.

Role of Intracardiac echocardiography in Atrial Fibrillation Ablation.

In the recent years, several new evidences support catheter-based ablation as a treatment modality of atrial fibrillation (AF). Based on a plenty of different applications, intracardiac echocardiography (ICE) is now a well-established technology in complex electrophysiological procedures, in particular in AF ablation. ICE contributes to improve the efficacy and safety of such procedures defining the anatomical structures involved in ablation procedures and monitoring in real time possible complications. In particular ICE allows: a correct identification of the endocardial structures; a guidance of transseptal puncture; an assessment of accurate placement of the circular mapping catheter; an indirect evaluation of evolving lesions during radiofrequency (RF) energy delivery via visualization of micro and macrobubbles tissue heating; assessment of catheter contact with cardiac tissues. Recently, also the feasibility of the integration of electroanatomical mapping (EAM) and intracardiac echocardiography has been demonstrated, combining accurate real time anatomical information with electroanatomical data. As a matter of fact, different techniques and ablation strategies have been developed throughout the years. In the setting of balloon-based ablation systems, recently adopted by an increasing number of centers, ICE might have a role in the choice of appropriate balloon size and to confirm accurate occlusion of pulmonary veins. Furthermore, in the era of minimally fluoroscopic ablation, ICE has successfully provided a contribute in reducing fluoroscopy time. The purpose of this review is to summarize the current applications of ICE in catheter based ablation strategies of atrial fibrillation, focusing-on electronically phased-array ICE.

Drug-refractory ventricular tachycardias after myocarditis: endocardial and epicardial radiofrequency catheter ablation.

BACKGROUND: Ventricular tachycardia (VT) is a significant therapeutic challenge in patients with myocarditis. This study aimed to assess the efficacy and safety of radiofrequency catheter ablation (RFCA) of VT in patients with myocarditis. METHODS AND RESULTS: We enrolled 20 patients (15 men; age, 42 [28-52] years) with a history of biopsy-proven viral myocarditis and drug-refractory VT; 5 patients presented with electrical storm. The median left ventricular ejection fraction was 55% (45-60%). All patients underwent endocardial RFCA with an irrigated catheter, using contact electroanatomic mapping. Recurrence of sustained VT after endocardial RFCA was treated with additional epicardial RFCA. Endocardial RFCA was acutely successful in 14 patients (70%) while in the remaining 6 (30%) clinical VT was successfully ablated by epicardial RFCA. In 1 patient, hemodynamic instability required an intra-aortic balloon pump to complete RFCA. No major complication occurred during or after RFCA. Over a median follow-up time of 28 (11-48) months, 18 patients (90%) remained free of sustained VT; 2 patients (10%, both with baseline left ventricular ejection fraction≤35%) died of acute heart failure unrelated to ventricular arrhythmias. CONCLUSIONS: In patients with myocarditis, RFCA of drug-refractory VT is feasible, safe, and effective. Epicardial RFCA should be considered as an important therapeutic option to increase success rate.