Jorge G. Quintanilla

Spanish National Cardiovascular Research Center (CNIC) & Hospital Clínico San Carlos, Madrid, Spain · Cardiac Electrophysiology Unit & Advanced Development in Arrhythmia Mechanisms and Therapy Lab.

RATIONALE: Costly proprietary panoramic multielectrode (64–256) acquisition systems are being increasingly used together with conventional electroanatomical mapping systems for persistent atrial fibrillation (PersAF) ablation. However, such approaches target alleged drivers (rotational/focal) regardless of their activation frequency dynamics. OBJEC...

Aims Cardiac optical mapping is the gold standard for measuring complex electrophysiology in ex-vivo heart preparations. However, new methods for optical mapping in-vivo have been elusive. We aimed at developing and validating an experimental method for performing in-vivo cardiac optical mapping in pig models. Methods and Results First, we charact...

A blation strategies to treat atrial fibrillation (AF) have evolved from the initial focal pulmonary vein ablation approach of Haïssaguerre et al 1 to new technical developments aimed at simplifying the procedure and increasing its safety. 2 However, ablation procedures are still associated with unsatisfactory rates of long-term success, particular...

Electrophysiological remodeling (HF-ER) in Heart Failure (HF) often includes the effect of chronically elevated intraventricular pressures (IVP) and promotes ventricular tachycardia/fibrillation (VT/VF). In addition, acutely-increased IVP have been associated with a higher rate of VT/VF episodes in Chronic HF (CHF). We hypothesized that increased I...

Aims: The mechanisms underlying ventricular fibrillation (VF) are still disputed. Recent studies have highlighted the role of KATP-channels. We hypothesized that, under certain conditions, VF can be driven by stable and epicardially detectable rotors in large hearts. To test our hypothesis, we used a swine model of accelerated VF by opening KATP-c...

Background Sudden cardiac death (SCD) is a leading cause of mortality and carries a dismal neurological outcome (NO) among patients admitted alive to acute cardiac care units (ACCU). A big share of SCD are found in ventricular fibrillation (VF). VF waveform is dynamic and it can be characterized by spectral analysis at the very time of ACCU admissi...

Background Structural remodeling in the context of persistent atrial fibrillation (PAF) has been mainly characterized by imaging techniques focused on fibrosis detection. Diffusion tensor imaging (DTI) has demonstrated its direct relationship with histological properties and myocyte organization, which may provide a more complete structural informa...

Electromechanical characterization during atrial fibrillation (AF) remains a significant gap in the understanding of AF-related atrial myopathy. This study reports mechanistic insights into the electromechanical remodeling process associated with AF progression and further demonstrates its prognostic value in the clinic. In pigs, sequential electro...

Background Ventricular fibrillation (VF) is one of the leading rhythm alterations documented at the time of medical assistance in patients with sudden cardiac death (SCD). There is an urgent need to improve current diagnostic tools to early predict neurological outcome in patients admitted alive to intensive care units. Objective To investigate th...

Background: Electromechanical assessment during atrial fibrillation (AF) remains a significant knowledge gap in patient-specific characterization of atrial remodeling. Objective: Study electromechanical remodeling progression in a long-term pig model of AF and establish the clinical prognostic value of the atrial electromechanical relationship. Met...

Delayed gadolinium-enhanced cardiac magnetic resonance (LGE-CMR) imaging requires novel and time-efficient approaches to characterize the myocardial substrate associated with ventricular arrhythmia in patients with ischemic cardiomyopathy. Using a translational approach in pigs and patients with established myocardial infarction, we tested and vali...

Clinicians, biologists, physicists, engineers, and computer scientists are coming together to better understand heart disease, which is currently the leading cause of death globally. Optical mapping, a high-speed fluorescence imaging technique that visualizes and measures key cardiac parameters such as action potentials, cytosolic calcium transient...

Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): - Ministerio de Ciencia e Innovación and the ProCNIC Foundation - Grant TEC2017-82408-R Background We aimed to validate a 3D methodology for transmural scar assessment using time-efficient upsampled models from 2D delayed gadolinium-en...

Catheter ablation remains the most effective and relatively minimally invasive therapy for rhythm control in patients with AF. Ablation has consistently shown a reduction of arrhythmia-related symptoms and significant improvement in patients’ quality of life compared with medical treatment. The ablation strategy relies on a well-established anatomi...

Optical cardiac mapping is an experimental method developed to record the electrical behavior of the heart, through the analysis of films filmed at high speed. Due to the conditions of the experiment along with the signal, a great amount of noise from different sources is stored. In this article, the comparison of the IIR type filters and the FIR f...

Modern cardiac electrophysiology has reported significant advances in the understanding of mechanisms underlying complex wave propagation patterns during atrial fibrillation (AF), although disagreements remain. One school of thought adheres to the long-held postulate that AF is the result of randomly propagating wavelets that wonder throughout the...

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 ai...

Aims: 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. Methods and results: Observational multicentre study (51 centres) including 4618 patien...

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...

Aims Myocardial infarction (MI) alters cardiac fibre organization with unknown consequences on ventricular arrhythmia. We used diffusion tensor imaging (DTI) of three-dimensional (3D) cardiac fibres and scar reconstructions to identify the main parameters associated with ventricular arrhythmia inducibility and ventricular tachycardia (VT) features...

To the Editor: We have read with great interest the study of Mark L. Brown [1], on ventricular fibrillation (VF) sensing using Medtronic implantable cardioverter defibrillators (ICDs). Dr. Brown describes the ventricular sensing process performed on Medtronic ICDs, but unfortunately his report does not show further data processed with proprietary f...

Aims: We aimed to study the differences in biventricular scar characterization using bipolar voltage mapping compared with state-of-the-art in vivo delayed gadolinium-enhanced cardiac magnetic resonance (LGE-CMR) imaging and ex vivo T1 mapping. Methods and results: Ten pigs with established myocardial infarction (MI) underwent in vivo scar chara...

Objective: Ventricular fibrillation (VF)-related sudden cardiac death (SCD) is a leading cause of mortality and morbidity. Current biological and imaging parameters show significant limitations on predicting cerebral performance at hospital admission. The AWAKE study (NCT03248557) is a multicentre observational study to validate a model based on s...

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 intr...

Panoramic optical mapping is the primary method for imaging electrophysiological activity from the entire outer surface of Langendorff-perfused hearts. To date, it is the only method of simultaneously measuring multiple key electrophysiological parameters, such as transmembrane voltage and intracellular free calcium, at high spatial and temporal re...

Optical Mapping (OM) sequences represent a very useful tool for registering cardiac bioelectric activity with high patio-temporal resolution. Conventional preprocessing of OM movies is mostly done with spatio-temporal filters, which could be improved for yielding better signal to noise ratio in the processed images. Also, the multimodal mapping, su...

Objective A safety threshold for baseline rhythm R-wave amplitudes during follow-up of implantable cardioverter defibrillators (ICD) has not been established. We aimed to analyse the amplitude distribution and undersensing rate during spontaneous episodes of ventricular fibrillation (VF), and define a safety amplitude threshold for baseline R-waves...

Atrial fibrillation (AF) recurrence rates after successful ablation procedures are still high and difficult to predict. This work studies the capability of entropy measured from intracardiac recordings as an indicator for recurrence outcome. Intra-atrial recordings from 31 AF patients were registered previously to an ablation procedure. Four electr...

The reported incidences of stenosis after radiofrequency ablation of pulmonary veins are highly variable. Moreover, most studies have focused on severe stenosis and have overlooked mild stenosis. Our aims were to study postablation morphological changes in the pulmonary veins and to evaluate preablation magnetic resonance imaging predictors for ste...

Resumen Introducción y objetivos La incidencia descrita de estenosis de venas pulmonares tras la ablación por radiofrecuencia es muy variable. Además, la mayoría de los estudios se han centrado en las estenosis graves y han prestado poca atención a las de carácter leve. El objetivo de este trabajo es estudiar los cambios morfológicos de las venas...

Early prognosis in comatose survivors after cardiac arrest due to ventricular fibrillation (VF) is unreliable, especially in patients undergoing mild hypothermia. We aimed at developing a reliable risk-score to enable early prediction of cerebral performance and survival. Sixty-one out of 239 consecutive patients undergoing mild hypothermia after c...

To the Editor: We thank Dr. Berjano for the opportunity to discuss the clinical relevance of our recent findings in two experimental models of radiofrequency (RF) catheter ablation.(1,2) First of all, it is important to recall that no model is without limitations. For example, the use of an in vivo model of cardiac lesions would have been desirable...

Introduction: Early reliable prognostication in comatose survivors after cardiac arrest due to ventricular fibrillation (VF) is very limited, especially in patients undergoing mild hypothermia. Hypothesis: Spectral analysis of VF before a DC shock will reflect the degree of acute cerebral injury as a consequence of time in VF and concomitant myocar...

Introduction: New generation open-irrigated catheters aim to improve irrigation efficiency. This may change lesion patterns, challenging operators. Indeed, safety issues have recently arisen. We aimed to experimentally assess 4 open-irrigated catheters, comparing lesion size, safety, and heat transfer. Methods: The thigh lesion model was employe...

Atrial fibrillation (AF) is an abnormal heart rhythm originated in the top chambers of the heart. The goal of pulmonary vein ablation for AF is regaining a normal heart rhythm; nevertheless restoration sinus rhythm is difficult to prognostic. Frequency spectrum was calculated from electrical activity registered along all the atria. We investigate w...

Purpose: There is great diversity of designs in open-irrigated ablation catheters. It is unknown whether they all create similar lesions with the same heat transfer. The purpose of this study was to independently compare, by a thermographic technique, the tissue heat transfer of 4 open-irrigated catheters. Methods: RF applications were performed on...

Purpose: Heart failure (HF) promotes sudden cardiac death (SCD). The interactions among HF electrical remodelling, high intraventricular pressures (IVP) and an ionic-imbalanced and catecholamine-rich milieu as the one in chronic HF (CHF) patients, are not well characterized. We aimed to evaluate the partial and combined contributions of these 3 fac...

Whether skeletal myoblast (SM) implants are proarrhythmic is still controversial due to conflicting pre-clinical and clinical data. We hypothesized that if SM implants are arrhythmogenic, they will facilitate the induction of ventricular tachyarrhythmias by promoting heterogeneous propagation of activation wavefronts. Skeletal myoblast cells were h...

The Stereotaxis(R) remote magnetic navigation system provides a new approach to ablation that could increase catheter stability. The aim was to determine whether improved tissue contact necessitates a change in traditional radiofrequency ablation parameters. The study compared ablation of atrioventricular nodal reentrant tachycardia (AVNRT) using r...

Introduction and objectives The Stereotaxis® remote magnetic navigation system provides a new approach to ablation that could increase catheter stability. The aim was to determine whether improved tissue contact necessitates a change in traditional radiofrequency ablation parameters. Methods The study compared ablation of atrioventricular nodal re...

Introduction and objectives. The Stereotaxis ® remote magnetic navigation system provides a new approach to ablation that could increase catheter stability. The aim was to determine whether improved tissue contact necessitates a change in traditional radiofrequency ablation parameters. Methods. The study compared ablation of atrioventricular nodal...