Anatomical targets and expected outcomes of catheter-based ablation of atrial fibrillation in 2020.

Anatomical-based approaches, targeting either pulmonary vein isolation (PVI) or additional extra PV regions, represent the most commonly used ablation treatments in symptomatic patients with atrial fibrillation (AF) recurrences despite antiarrhythmic drug therapy. PVI remains the main anatomical target during catheter-based AF ablation, with the aid of new technological advances as contact force monitoring to increase safety and effective radiofrequency (RF) lesions. Nowadays, cryoballoon ablation has also achieved the same level of scientific evidence in patients with paroxysmal AF undergoing PVI. In parallel, electrical isolation of extra PV targets has progressively increased, which is associated with a steady increase in complex cases undergoing ablation. Several atrial regions as the left atrial posterior wall, the vein of Marshall, the left atrial appendage, or the coronary sinus have been described in different series as locations potentially involved in AF initiation and maintenance. Targeting these regions may be challenging using conventional point-by-point RF delivery, which has opened new opportunities for coadjuvant alternatives as balloon ablation or selective ethanol injection. Although more extensive ablation may increase intraprocedural AF termination and freedom from arrhythmias during the follow-up, some of the targets to achieve such outcomes are not exempt of potential severe complications. Here, we review and discuss current anatomical approaches and the main ablation technologies to target atrial regions associated with AF initiation and maintenance.This work was supported by the European Regional Development Fund, the Spanish Ministry of Science and Innovation (SAF2016- 80324-R), and the Fundación Interhospitalaria para la Investigación Cardiovascular (FIC). The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Spanish Ministry of Science and Innovation and the Pro-CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505). Giulio La Rosa has received a fellowship grant from the joint program between the Heart Rhythm Association of the Spanish Society of Cardiology (ARC) and CNIC.S

Lesion Index Titration Using Contact-Force Technology Enables Safe and Effective Radiofrequency Lesion Creation at the Root of the Aorta and Pulmonary Artery

BACKGROUND: Ablation of some myocardial substrates requires catheter-based radiofrequency delivery at the root of a great artery. We studied the safety and efficacy parameters associated with catheter-based radiofrequency delivery at the root of the aorta and pulmonary artery. METHODS: Thirty-six pigs underwent in-vivo catheter-based ablation under continuous contact-force and lesion index (power, contact-force, and time) monitoring during 60-s radiofrequency delivery with an open-irrigated tip catheter. Twenty-eight animals were allocated to groups receiving 40 W (n=9), 50 W (n=10), or 60 W (n=9) radiofrequency energy, and acute (n=22) and chronic (n=6) arterial wall damage was quantified by multiphoton microscopy in ex vivo samples. Adjacent myocardial lesions were quantified in parallel samples. The remaining 8 pigs were used to validate safety and efficacy parameters. RESULTS: Acute collagen and elastin alterations were significantly associated with radiofrequency power, although chronic assessment revealed vascular wall recovery in lesions without steam pop. The main parameters associated with steam pops were median peak temperature >42°C and impedance falls >23 ohms. Unlike other parameters, lesion index values of 9.1 units (interquartile range, 8.7-9.8) were associated with the presence of adjacent myocardial lesions in both univariate ( P=0.03) and multivariate analyses ( P=0.049; odds ratio, 1.99; 95% CI, 1.02-3.98). In the validation group, lesion index values using 40 W over a range of contact-forces correlated with the size of radiofrequency lesions (R2=0.57; P=0.03), with no angiographic or histopathologic signs of coronary artery damage. CONCLUSIONS: Lesion index values obtained during 40 W radiofrequency applications reliably monitor safe and effective lesion creation at the root of the great arteries.This study was supported by the Fundación Interhospitalaria para la Investigación Cardiovascular (FIC) and the Heart Rhythm Section of the Spanish Society of Cardiology. The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Ministry of Science, Innovation and Universities and the Pro CNIC Foundation. The CNIC is a Severo Ochoa Center of Excellence (SEV-2015- 0505). This study was supported by grants from Fondo Europeo de Desarrollo Regional (CB16/11/00458) and the Spanish Ministry of Science, Innovation and Universities (SAF2016-80324-R).S

Aneurismas de aorta ascendente y válvula aórtica: comparación de la histología de la aorta descendente en pacientes con válvula aórtica bicúspide y pacientes con válvula aórtica tricúspide

"INTRODUCCIÓN": La válvula aórtica bicúspide (VAB) es la cardiopatía congénita más frecuente y afecta al 0,5-2 por ciento de la población. Los pacientes con VAB tienen mayor predisposición al desarrollo de dilatación aórtica, conocido factor de riesgo para el desarrollo de disección y-o rotura aórtica. Los mecanismos que conducen a la dilatación aórtica en estos pacientes no son bien conocidos, pero podrían relacionarse con una debilidad estructural congénita en la pared aórtica (aortopatía bicúspide). La hipótesis de este trabajo es que los aneurismas que se desarrollan en el seno de una VAB deberían presentar características histológicas distintivas respecto a los que aparecen en los pacientes con válvula aórtica tricúspide (VAT). "MÉTODOS": Se incluyeron de forma prospectiva 134 pacientes (75 por ciento varones, edad media 63 años) sometidos a cirugía electiva sobre la aorta ascendente y se clasificaron en dos grupos en función de la morfología valvular. Se obtuvieron muestras de aorta ascendente durante la intervención y se estudiaron los siguientes aspectos histológicos: grosor total de la capa media, patrón de vascularización de la capa media y los cambios degenerativos (fibrosis, fragmentación de las fibras elásticas, necrosis quística de la media y calcificación). Se construyeron además modelos de regresión para estudiar el impacto de otras variables clínicas en los hallazgos histológicos. "RESULTADOS": No se encontraron diferencias en cuanto al grosor de la capa media entre los dos grupos de pacientes. Los pacientes con VAT mostraron una vascularización más rica de la capa media, caracterizada por una mayor profundidad de penetración de los vasa vasorum. Además presentaron mayor grado de fibrosis y de fragmentación de las fibras elásticas, pero no se encontraron diferencias entre los dos grupos en cuanto a la necrosis quística de la media o la presencia de calcificación en la capa media. En el análisis multivariado la morfología valvular fue predictor independiente de la penetración de los vasa vasorum, pero no de los cambios degenerativos analizados

QRS duration reflects underlying changes in conduction velocity during increased intraventricular pressure and heart failure

Pressure overload and heart failure electrophysiological remodeling (HF-ER) in pigs are associated with decreased conduction velocity (CV) and dispersion of repolarization, which lead to higher risk of ventricular arrhythmia. This work aimed to establish the correlation between QRS complex duration and underlying changes in CV during increased intraventricular pressure (IVP) and/or HF-ER ex-vivo, and to determine whether QRS duration could be sensitive to an acute increase in left ventricular (LV) afterload in-vivo. HF-ER was induced in 7 pigs by high-rate ventricular pacing. Seven weight-matched animals were used as controls. Isolated Langendorff-perfused hearts underwent programmed ventricular stimulation to study QRS complex duration and CV under low/high IVP, using volume-conducted ECG and epicardial optical mapping, respectively. Four additional pigs underwent open-chest surgery to increase LV afterload by partially clamping the ascending aorta, while measuring QRS complex duration during sinus rhythm (SR). In 13 hearts included for analysis, both HF-ER and increased IVP showed significantly slower epicardial CV (-40% and -15%, p < 0.001 and p = 0.004, respectively), which correlated with similar widening of the QRS complex (+41% and +17%, p = 0.005 and p < 0.001, respectively). HF-ER hearts shower larger prolongation of the QRS complex than controls upon increasing the IVP (+21% vs. +12%, respectively. HF-ER*IVP interaction: p = 0.004). QRS complex widened after increasing LV afterload in-vivo (n=3), with correlation between QRS duration and aortic diastolic pressures (R = 0.58, p < 0.001). In conclusion, high IVP and/or HF-ER significantly decrease CV, which correlates with QRS widening on the ECG during ventricular pacing. Increased myocardial wall stress also widens the QRS complex during SR in-vivo.The CNIC is supported by the Ministry of Economy, Industry and Competitiveness and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505). This study was supported by grants from Fondo Europeo de Desarrollo Regional (CB16/11/00458), Instituto de Salud Carlos III [RD06/0003/0009 (REDINSCOR), RD12/0042/0036 (RIC)], and Spanish Ministry of Economy and Competitiveness (MINECO) (SAF2016-80324-R). The study was also partially supported by the Fundacion Interhospitalaria para la Investigacion Cardiovascular (FIC).S

Gestión de las salas de procedimientos invasivos cardiológicos durante el brote de coronavirus COVID-19: Documento de consenso de la Asociación de Cardiología Intervencionista y la Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología

During March 2020, the SARS-CoV-2 virus spread throughout Europe, with the spread being especially intense in Italy and Spain. Given the emergency created by the COVID-19 outbreak, routine activity has been altered in most cardiac catheterization and electrophysiology labs. Health staff working in these areas are faced with performing procedures in patients with a confirmed diagnosis of COVID-19 or with uncertainty in unconfirmed cases. This article is a consensus document of the Interventional Cardiology Association and Heart Rhythm Association of the Spanish Society of Cardiology and aims to provide information to health care professionals working in these invasive cardiology facilities (cardiac catheterization and electrophysiology labs, pacemaker implantation) in order to guarantee quality patient care and adequate levels of infection prevention.Durante marzo de 2020, el virus SARS-CoV-2 se ha extendido por toda Europa, con especial intensidad en Italia y España. Ante la emergencia creada por el brote de COVID-19, la inmensa mayoría de las salas de hemodinámica y electrofisiología han visto alterada su actividad habitual. Además se enfrentan a la realización de procedimientos en pacientes con diagnóstico confirmado de COVID-19 o con la incertidumbre en casos no confirmados. El presente texto es un documento de consenso de la Asociación de Cardiología Intervencionista y la Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología que pretende dar información al personal sanitario de estas instalaciones de cardiología invasiva (hemodinámica y electrofisiología y marcapasos) para garantizar una atención de calidad a los pacientes así como unos niveles los niveles adecuados de prevención de la infección

Personalized monitoring of electrical remodelling during atrial fibrillation progression via remote transmissions from implantable devices.

Atrial electrical remodelling (AER) is a transitional period associated with the progression and long-term maintenance of atrial fibrillation (AF). We aimed to study the progression of AER in individual patients with implantable devices and AF episodes. Observational multicentre study (51 centres) including 4618 patients with implantable cardioverter-defibrillator +/-resynchronization therapy (ICD/CRT-D) and 352 patients (2 centres) with pacemakers (median follow-up: 3.4 years). Atrial activation rate (AAR) was quantified as the frequency of the dominant peak in the signal spectrum of AF episodes with atrial bipolar electrograms. Patients with complete progression of AER, from paroxysmal AF episodes to electrically remodelled persistent AF, were used to depict patient-specific AER slopes. A total of 34 712 AF tracings from 830 patients (87 with pacemakers) were suitable for the study. Complete progression of AER was documented in 216 patients (16 with pacemakers). Patients with persistent AF after completion of AER showed ∼30% faster AAR than patients with paroxysmal AF. The slope of AAR changes during AF progression revealed patient-specific patterns that correlated with the time-to-completion of AER (R2 = 0.85). Pacemaker patients were older than patients with ICD/CRT-Ds (78.3 vs. 67.2 year olds, respectively, P < 0.001) and had a shorter median time-to-completion of AER (24.9 vs. 93.5 days, respectively, P = 0.016). Remote transmissions in patients with ICD/CRT-D devices enabled the estimation of the time-to-completion of AER using the predicted slope of AAR changes from initiation to completion of electrical remodelling (R2 = 0.45). The AF progression shows patient-specific patterns of AER, which can be estimated using available remote-monitoring technology.The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia, Innovacion y Universidades (MCNU), and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015–0505). This study was supported by grants from the Fondo Europeo de Desarrollo Regional (CB16/11/00458) and the Spanish MCNU (SAF2016-80324-R). The study was also partially supported by the Fundacion Interhospitalaria para la Investigacion Cardiovascular (FIC, Madrid, Spain) and the Heart Rhythm Association of the Spanish Society of Cardiology (D.F.-R., J.J.G.-F.). J.J. is supported by R01 Grant HL122352 from the National Heart Lung and Blood Institute, USA National Institutes of Health.S

Personalized monitoring of electrical remodelling during atrial fibrillation progression via remote transmissions from implantable devices.

Atrial electrical remodelling (AER) is a transitional period associated with the progression and long-term maintenance of atrial fibrillation (AF). We aimed to study the progression of AER in individual patients with implantable devices and AF episodes. Observational multicentre study (51 centres) including 4618 patients with implantable cardioverter-defibrillator +/-resynchronization therapy (ICD/CRT-D) and 352 patients (2 centres) with pacemakers (median follow-up: 3.4 years). Atrial activation rate (AAR) was quantified as the frequency of the dominant peak in the signal spectrum of AF episodes with atrial bipolar electrograms. Patients with complete progression of AER, from paroxysmal AF episodes to electrically remodelled persistent AF, were used to depict patient-specific AER slopes. A total of 34 712 AF tracings from 830 patients (87 with pacemakers) were suitable for the study. Complete progression of AER was documented in 216 patients (16 with pacemakers). Patients with persistent AF after completion of AER showed ∼30% faster AAR than patients with paroxysmal AF. The slope of AAR changes during AF progression revealed patient-specific patterns that correlated with the time-to-completion of AER (R2 = 0.85). Pacemaker patients were older than patients with ICD/CRT-Ds (78.3 vs. 67.2 year olds, respectively, P < 0.001) and had a shorter median time-to-completion of AER (24.9 vs. 93.5 days, respectively, P = 0.016). Remote transmissions in patients with ICD/CRT-D devices enabled the estimation of the time-to-completion of AER using the predicted slope of AAR changes from initiation to completion of electrical remodelling (R2 = 0.45). The AF progression shows patient-specific patterns of AER, which can be estimated using available remote-monitoring technology.The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia, Innovacion y Universidades (MCNU), and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015–0505). This study was supported by grants from the Fondo Europeo de Desarrollo Regional (CB16/11/00458) and the Spanish MCNU (SAF2016-80324-R). The study was also partially supported by the Fundacion Interhospitalaria para la Investigacion Cardiovascular (FIC, Madrid, Spain) and the Heart Rhythm Association of the Spanish Society of Cardiology (D.F.-R., J.J.G.-F.). J.J. is supported by R01 Grant HL122352 from the National Heart Lung and Blood Institute, USA National Institutes of Health.S