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1.
Heart Rhythm ; 20(5): 658-665, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36640853

RESUMEN

BACKGROUND: The benefit of an anterior mitral line (AML) in patients with persistent atrial fibrillation (AF) and anterior atrial scar undergoing ablation has never been investigated. OBJECTIVE: The purpose of this study was to evaluate the outcomes of AML in addition to standard treatment compared to standard treatment alone (no AML) in this subset of patients. METHODS: Patients with persistent AF and anterior low-voltage zone (LVZ) treated with AML in 3 centers were retrospectively enrolled. The patients were matched in 1:1 fashion with patients having persistent AF and anterior LVZ who underwent conventional ablation in the same centers. Matching parameters were age, LVZ burden, and repeated ablation. Primary endpoint was AF/atrial tachycardia (AT) recurrence. RESULTS: One hundred eight-six patients (age 66 ± 9 years; 34% women) were selected and divided into 2 matched groups. Bidirectional conduction block was achieved in 95% of AML. After median follow-up of 2 years, AF/AT recurrence occurred in 29% of the patients in the AML group vs 48% in the no AML group (log-rank P = .024). On Cox regression multivariate analysis, left atrial volume (hazard ratio [HR] 1.03; P = .006) and AML (HR 0.46; P = .003) were significantly associated with the primary endpoint. On univariate logistic regression, lower body mass index, older age, extensive anterior LVZ, and position of the left atrial activation breakthrough away from the AML were associated with first-pass AML block. CONCLUSION: In this retrospective matched analysis of patients with persistent AF and anterior scar, AML in addition to standard treatment was associated with improved AF/AT-free survival compared to standard treatment alone.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Venas Pulmonares , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , Fibrilación Atrial/complicaciones , Fibrilación Atrial/cirugía , Estudios Retrospectivos , Cicatriz/diagnóstico , Cicatriz/etiología , Resultado del Tratamiento , Técnicas Electrofisiológicas Cardíacas , Taquicardia , Recurrencia , Venas Pulmonares/cirugía
2.
Am J Physiol Heart Circ Physiol ; 323(4): H763-H773, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-36018757

RESUMEN

Cardiac arrhythmias are associated with cardiovascular morbidity and mortality. Cardiac electrophysiology studies (EPS) use intracardiac catheter recording and stimulation for profound evaluation of the heart's electrical properties. The main clinical application is investigation and treatment of rhythm disorders. These techniques have been translated to the murine setting to open opportunities for detailed evaluation of the impact of different characteristics (including genetics) and interventions on cardiac electrophysiology and -pathology. Currently, a detailed description of the technique of murine transjugular EPS (which is the standard route of catheter introduction) is lacking. This article provides detailed information on EPS in mice via the transjugular route. This includes catheter placement, stimulation protocols, intracardiac tracing interpretation, artifact reduction, and surface ECG recording. In addition, reference values as obtained in C57BL/6N mice are presented for common electrophysiological parameters. This detailed methodological description aims to increase accessibility and standardization of EPS in mice. Ultimately, also human research and patient care may benefit from translation of the knowledge obtained in preclinical models using this technique.NEW & NOTEWORTHY Electrophysiology studies (EPS) allow in-depth evaluation of cardiac electrophysiology and -pathology. These techniques have been adapted to the murine setting for (translational) studies, mainly focusing on arrhythmogenesis. Despite the frequent application of EPS via the transjugular route, a thorough description of the technique is currently lacking. This article aims to function as a comprehensive guide, also elaborating (for the first time) on nonsurgical aspects such as catheter positioning, tracing artifacts, stimulation protocols, and reference values.


Asunto(s)
Arritmias Cardíacas , Técnicas Electrofisiológicas Cardíacas , Animales , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas/métodos , Corazón , Humanos , Ratones , Ratones Endogámicos C57BL
4.
Thromb Haemost ; 121(3): 270-278, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32838473

RESUMEN

Atrial fibrillation (AF) is a complex condition requiring holistic management with multiple treatment decisions about optimal thromboprophylaxis, symptom control (and prevention of AF progression), and identification and management of concomitant cardiovascular risk factors and comorbidity. Sometimes the information needed for treatment decisions is incomplete, as available classifications of AF mostly address a single domain of AF (or patient)-related characteristics. The most widely used classification of AF based on AF episode duration and temporal patterns (that is, the classification to first-diagnosed, paroxysmal, persistent/long-standing persistent, and permanent AF) has contributed to a better understanding of AF prevention and treatment but its limitations and the need for a multidimensional AF classification have been recognized as more complex treatment options became available. We propose a paradigm shift from classification toward a structured characterization of AF, addressing specific domains having treatment and prognostic implications to become a standard in clinical practice, thus aiming to streamline the assessment of AF patients at all health care levels facilitating communication among physicians, treatment decision-making, and optimal risk evaluation and management of AF patients. Specifically, we propose the 4S-AF structured pathophysiology-based characterization (rather than classification) scheme that includes four AF- and patient-related domains-Stroke risk, Symptoms, Severity of AF burden, and Substrate severity-and provide a hypothetical model for the use of 4S-AF characterization scheme to aid treatment decision making concerning the management of patients with AF in clinical practice.


Asunto(s)
Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Accidente Cerebrovascular/etiología , Animales , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/terapia , Manejo de la Enfermedad , Humanos , Pronóstico , Factores de Riesgo , Índice de Severidad de la Enfermedad
6.
Eur J Heart Fail ; 22(12): 2349-2369, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33136300

RESUMEN

Cardiac resynchronization therapy (CRT) is one of the most effective therapies for heart failure with reduced ejection fraction and leads to improved quality of life, reductions in heart failure hospitalization rates and all-cause mortality. Nevertheless, up to two-thirds of eligible patients are not referred for CRT. Furthermore, post-implantation follow-up is often fragmented and suboptimal, hampering the potential maximal treatment effect. This joint position statement from three European Society of Cardiology Associations, Heart Failure Association (HFA), European Heart Rhythm Association (EHRA) and European Association of Cardiovascular Imaging (EACVI), focuses on optimized implementation of CRT. We offer theoretical and practical strategies to achieve more comprehensive CRT referral and post-procedural care by focusing on four actionable domains: (i) overcoming CRT under-utilization, (ii) better understanding of pre-implant characteristics, (iii) abandoning the term 'non-response' and replacing this by the concept of disease modification, and (iv) implementing a dedicated post-implant CRT care pathway.


Asunto(s)
Terapia de Resincronización Cardíaca , Insuficiencia Cardíaca , Vías Clínicas , Mal Uso de los Servicios de Salud , Insuficiencia Cardíaca/terapia , Humanos , Calidad de Vida , Derivación y Consulta , Resultado del Tratamiento
9.
J Cardiovasc Electrophysiol ; 30(8): 1367-1368, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31077499

RESUMEN

We present a remarkable maximal capacity exercise test of a 52-year-old patient diagnosed with Brugada syndrome (BrS). As the patient reaches a supranormal sinus heart rate, the type-1 electrocardiogram pattern of BrS appeared and then disappeared immediately after cessation of exercise.


Asunto(s)
Síndrome de Brugada/diagnóstico , Electrocardiografía , Prueba de Esfuerzo , Sistema de Conducción Cardíaco/fisiopatología , Frecuencia Cardíaca , Potenciales de Acción , Síndrome de Brugada/fisiopatología , Técnicas Electrofisiológicas Cardíacas , Tolerancia al Ejercicio , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de Tiempo
10.
Kardiol Pol ; 77(4): 437-444, 2019 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-30835335

RESUMEN

BACKGROUND The Jessa Atrial Fibrillation Knowledge Questionnaire (JAKQ) was successfully used to assess knowledge gaps in patients with atrial fibrillation (AF). AIMS To evaluate the regional differences among Polish patients in their awareness of AF diagnosis and oral anticoagulation use. METHODS A total of 1583 patients with AF at a median (IQR) age of 72 (66-79) years completed the JAKQ in 3 cardiology centers (center I, Kraków; center II, Torun; center III, Kielce) from January 2017 to June 2018. The final analysis included 1525 patients, 32.9% were on vitamin K antagonists (VKAs) and 67.1% on non-VKA oral anticoagulants (NOACs), that is, rivaroxaban and dabigatran (28.9% each), and apixaban (9.3%). RESULTS The mean (SD) score on the JAKQ was 55.5% (18.4%) with better results among patients on VKAs compared with NOACs (58% [18.3%] vs 54.3% [18.4%]; P = 0.0002) with time from AF diagnosis more than 12 months (57.4% [17.5%] vs 50% [19.9%]; P <0.0001). There was a significant difference in the knowledge scores between the 3 centers (I, 59.5%; II, 48.5%; III, 54.3%; P <0.0001). In all centers the number of correct answers correlated inversely with patient's age (r = -0.20; P <0.0001). NOACs were more frequently used in center III. The percentage of correct responses was lower in patients on reduced NOAC doses (35.4% of patients on NOACs), compared with the full-dose NOAC groups in center I (56.9% vs 62.5%; P = 0.012) and II (48.1% vs 56.2%; P = 0.003). CONCLUSIONS Patients from a high-volume academic center showed better knowledge than their peers from district hospitals. There are large regional differences in prescription patterns of oral anticoagulants, including the preferred NOAC.


Asunto(s)
Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Manejo de la Enfermedad , Educación del Paciente como Asunto , Conocimiento de la Medicación por el Paciente , Administración Oral , Anciano , Anticoagulantes/administración & dosificación , Dabigatrán/administración & dosificación , Dabigatrán/uso terapéutico , Femenino , Hospitales de Distrito , Hospitales de Enseñanza , Humanos , Masculino , Polonia , Pirazoles/administración & dosificación , Pirazoles/uso terapéutico , Piridonas/administración & dosificación , Piridonas/uso terapéutico , Rivaroxabán/administración & dosificación , Rivaroxabán/uso terapéutico , Encuestas y Cuestionarios
11.
JACC Clin Electrophysiol ; 4(12): 1541-1552, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30573117

RESUMEN

OBJECTIVES: This study aimed: 1) to determine the voltage correlation between sinus rhythm (SR) and atrial fibrillation (AF)/atrial flutter (AFL) using multielectrode fast automated mapping; 2) to identify a bipolar voltage cutoff for scar and/or low voltage areas (LVAs); and 3) to examine the reproducibility of voltage mapping in AF. BACKGROUND: It is unclear if bipolar voltage cutoffs should be adjusted depending on the rhythm and/or area being mapped. METHODS: High-density mapping was performed first in SR and afterward in induced AF/AFL. In some patients, 2 maps were performed during AF. Maps were combined to create a new one. Points of <1 mm difference were analyzed. Correlation was explored with scatterplots and agreement analysis was assessed with Bland-Altman plots. The generalized additive model was also applied. RESULTS: A total of 2,002 paired-points were obtained. A cutoff of 0.35 mV in AFL predicted a sinus voltage of 0.5 mV (95% confidence interval [CI]: 0.12 to 2.02) and of 0.24 mV in AF (95% CI: 0.11 to 2.18; specificity [SP]: 0.94 and 0.96; sensitivity [SE]: 0.85 and 0.75, respectively). When generalized additive models were used, a cutoff of 0.38 mV was used for AFL for predicting a minimum value of 0.5 mV in SR (95% CI: 0.5 to 1.6; SP: 0.94, SE: 0.88) and of 0.31 mV for AF (95% CI: 0.5 to 1.2; SP: 0.95, SE: 0.82). With regard to AF maps, there was no change in the classification of any left atrial region other than the roof. CONCLUSIONS: It is possible to establish new cutoffs for AFL and/or AF with acceptable validity in predicting a sinus voltage of <0.5 mV. Multielectrode fast automated mapping in AFL and/or AF seems to be reliable and reproducible when classifying LVAs. These observations have clinical implications for left atrial voltage distribution and in procedures in which scar distribution is used to guide pulmonary vein isolation and/or re-isolation.


Asunto(s)
Fibrilación Atrial/diagnóstico , Técnicas Electrofisiológicas Cardíacas/métodos , Técnicas Electrofisiológicas Cardíacas/normas , Anciano , Aleteo Atrial/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados
12.
Eur Heart J ; 39(16): 1394-1403, 2018 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-29300888

RESUMEN

Aims: To evaluate the effect of telemonitoring on adherence to non-vitamin K antagonist oral anticoagulants (NOACs) in atrial fibrillation (AF) patients. Methods and results: A randomized, single-blind, crossover, controlled trial in 48 AF patients on once or twice daily (OD or BID) NOAC. The Medication Event Monitoring System tracked NOAC intake during three phases of 3 months each: daily telemonitoring, telemonitoring with immediate telephone feedback in case of intake errors, and an observation phase without daily transmissions. Unprotected days were defined as ≥ 3 or ≥ 1 consecutively missed doses for a BID or OD NOAC, respectively, or excess dose intake. Cost-effectiveness was calculated based on anticipated stroke reduction derived from patients' risk profile and measured intake. Persistence over the entire study was 98%. Telemonitoring-only already led to very high taking and regimen adherence (97.4% respectively 93.8%). Nevertheless, direct feedback further improved both to 99.0% and 96.8%, respectively (P < 0.001 respectively P = 0.002). Observation without daily monitoring resulted in a significant waning of taking adherence (94.3%; P = 0.049). Taking adherence was significantly higher for OD compared to BID NOAC, although unprotected days were similar. Feedback intervention had an incremental cost of €344 289 to prevent one stroke, but this could be as low as €15 488 in high-risk patients with low adherence and optimized technology. Conclusion: Telemonitoring resulted in high NOAC adherence due to the notion of being watched, as evidenced by the rapid decline during the observation period. Feedback further optimized adherence. Telemonitoring with or without feedback may be a cost-effective approach in high-risk patients deemed poorly adherent.


Asunto(s)
Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Cumplimiento de la Medicación , Monitoreo Ambulatorio/métodos , Administración Oral , Anciano , Anticoagulantes/administración & dosificación , Fibrilación Atrial/complicaciones , Análisis Costo-Beneficio , Estudios Cruzados , Retroalimentación , Femenino , Humanos , Masculino , Monitoreo Ambulatorio/economía , Pirazoles/administración & dosificación , Pirazoles/uso terapéutico , Piridonas/administración & dosificación , Piridonas/uso terapéutico , Rivaroxabán/administración & dosificación , Rivaroxabán/uso terapéutico , Método Simple Ciego , Accidente Cerebrovascular/prevención & control
13.
Europace ; 20(3): 395-407, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29300976

RESUMEN

There are major challenges ahead for clinicians treating patients with atrial fibrillation (AF). The population with AF is expected to expand considerably and yet, apart from anticoagulation, therapies used in AF have not been shown to consistently impact on mortality or reduce adverse cardiovascular events. New approaches to AF management, including the use of novel technologies and structured, integrated care, have the potential to enhance clinical phenotyping or result in better treatment selection and stratified therapy. Here, we report the outcomes of the 6th Consensus Conference of the Atrial Fibrillation Network (AFNET) and the European Heart Rhythm Association (EHRA), held at the European Society of Cardiology Heart House in Sophia Antipolis, France, 17-19 January 2017. Sixty-two global specialists in AF and 13 industry partners met to develop innovative solutions based on new approaches to screening and diagnosis, enhancing integration of AF care, developing clinical pathways for treating complex patients, improving stroke prevention strategies, and better patient selection for heart rate and rhythm control. Ultimately, these approaches can lead to better outcomes for patients with AF.


Asunto(s)
Fibrilación Atrial/diagnóstico , Fibrilación Atrial/terapia , Cardiología/normas , Prestación Integrada de Atención de Salud/normas , Fibrilación Atrial/epidemiología , Fibrilación Atrial/fisiopatología , Consenso , Difusión de Innovaciones , Humanos , Valor Predictivo de las Pruebas , Resultado del Tratamiento
14.
Europace ; 20(2): 225-233, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29040548

RESUMEN

We are in the midst of a digital revolution in health care, although the application of new and useful technology in routine clinical practice is variable. The Characterizing Atrial fibrillation by Translating its Causes into Health Modifiers in the Elderly (CATCH ME) Consortium, in collaboration with the European Society of Cardiology (ESC), has funded the creation of two applications (apps) in atrial fibrillation (AF) for use in smartphones and tablets. The patient app aims to enhance patient education, improve communication between patients and health care professionals, and encourage active patient involvement in the management of their condition. The health care professional app is designed as an interactive management tool incorporating the new ESC Practice Guidelines on AF and supported by the European Heart Rhythm Association (EHRA), with the aim of improving best practice approaches for the care of patients with AF. Both stand-alone apps are now freely available for Android and iOS devices though the Google Play, Amazon, and Apple stores. In this article, we outline the rationale for the design and implementation of these apps. Our objective is to demonstrate the value of integrating novel digital technology into clinical practice, with the potential for patient engagement, optimization of pharmacological and interventional therapy in AF, and ultimately to improve patient outcomes.


Asunto(s)
Fibrilación Atrial/terapia , Comunicación , Computadoras de Mano , Prestación Integrada de Atención de Salud , Aplicaciones Móviles , Relaciones Médico-Paciente , Teléfono Inteligente , Telemedicina/instrumentación , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Actitud del Personal de Salud , Actitud hacia los Computadores , Computadoras de Mano/normas , Prestación Integrada de Atención de Salud/normas , Europa (Continente) , Conocimientos, Actitudes y Práctica en Salud , Humanos , Aplicaciones Móviles/normas , Educación del Paciente como Asunto , Guías de Práctica Clínica como Asunto , Teléfono Inteligente/normas , Sociedades Médicas , Telemedicina/normas
15.
Europace ; 19(12): 1909-1922, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-29126278
16.
Europace ; 16(7): 946-64, 2014 07.
Artículo en Inglés | MEDLINE | ID: mdl-24792380

RESUMEN

Despite the advent of non-fluoroscopic technology, fluoroscopy remains the cornerstone of imaging in most interventional electrophysiological procedures, from diagnostic studies over ablation interventions to device implantation. Moreover, many patients receive additional X-ray imaging, such as cardiac computed tomography and others. More and more complex procedures have the risk to increase the radiation exposure, both for the patients and the operators. The professional lifetime attributable excess cancer risk may be around 1 in 100 for the operators, the same as for a patient undergoing repetitive complex procedures. Moreover, recent reports have also hinted at an excess risk of brain tumours among interventional cardiologists. Apart from evaluating the need for and justifying the use of radiation to assist their procedures, physicians have to continuously explore ways to reduce the radiation exposure. After an introduction on how to quantify the radiation exposure and defining its current magnitude in electrophysiology compared with the other sources of radiation, this position paper wants to offer some very practical advice on how to reduce exposure to patients and staff. The text describes how customization of the X-ray system, workflow adaptations, and shielding measures can be implemented in the cath lab. The potential and the pitfalls of different non-fluoroscopic guiding technologies are discussed. Finally, we suggest further improvements that can be implemented by both the physicians and the industry in the future. We are confident that these suggestions are able to reduce patient and operator exposure by more than an order of magnitude, and therefore think that these recommendations are worth reading and implementing by any electrophysiological operator in the field.


Asunto(s)
Cateterismo Cardíaco/normas , Técnicas Electrofisiológicas Cardíacas/normas , Exposición Profesional/normas , Implantación de Prótesis/normas , Dosis de Radiación , Traumatismos por Radiación/prevención & control , Radiografía Intervencional/normas , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/instrumentación , Técnicas Electrofisiológicas Cardíacas/efectos adversos , Técnicas Electrofisiológicas Cardíacas/instrumentación , Diseño de Equipo , Fluoroscopía/normas , Humanos , Exposición Profesional/efectos adversos , Exposición Profesional/prevención & control , Salud Laboral/normas , Seguridad del Paciente/normas , Implantación de Prótesis/efectos adversos , Implantación de Prótesis/instrumentación , Traumatismos por Radiación/etiología , Monitoreo de Radiación/normas , Protección Radiológica/normas , Radiografía Intervencional/efectos adversos , Radiografía Intervencional/instrumentación , Medición de Riesgo , Factores de Riesgo , Flujo de Trabajo
17.
Europace ; 15(7): 927-36, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23729412

RESUMEN

Implantations of cardiac devices therapies and ablation procedures frequently depend on accurate and reliable imaging modalities for pre-procedural assessments, intra-procedural guidance, detection of complications, and the follow-up of patients. An understanding of echocardiography, cardiovascular magnetic resonance imaging, nuclear cardiology, X-ray computed tomography, positron emission tomography, and vascular ultrasound is indispensable for cardiologists, electrophysiologists as well as radiologists, and it is currently recommended that physicians should be trained in several imaging modalities. There are, however, no current guidelines or recommendations by electrophysiologists, cardiac imaging specialists, and radiologists, on the appropriate use of cardiovascular imaging for selected patient indications, which needs to be addressed. A Policy Conference on the use of imaging in electrophysiology and device management, with representatives from different expert areas of radiology and electrophysiology and commercial developers of imaging and device technologies, was therefore jointly organized by European Heart Rhythm Association (EHRA), the Council of Cardiovascular Imaging and the European Society of Cardiac Radiology (ESCR). The objectives were to assess the state of the level of evidence and a first step towards a consensus document for currently employed imaging techniques to guide future clinical use, to elucidate the issue of reimbursement structures and health economy, and finally to define the need for appropriate educational programmes to ensure clinical competence for electrophysiologists, imaging specialists, and radiologists.


Asunto(s)
Estimulación Cardíaca Artificial/normas , Cardiología/normas , Ablación por Catéter/normas , Diagnóstico por Imagen/normas , Cardioversión Eléctrica/normas , Técnicas Electrofisiológicas Cardíacas/normas , Sociedades Médicas/normas , Estimulación Cardíaca Artificial/economía , Cardiología/economía , Cardiología/educación , Ablación por Catéter/economía , Consenso , Análisis Costo-Beneficio , Desfibriladores Implantables/normas , Diagnóstico por Imagen/economía , Diagnóstico por Imagen/métodos , Educación Médica , Cardioversión Eléctrica/economía , Cardioversión Eléctrica/instrumentación , Técnicas Electrofisiológicas Cardíacas/economía , Europa (Continente) , Medicina Basada en la Evidencia , Costos de la Atención en Salud , Humanos , Reembolso de Seguro de Salud , Marcapaso Artificial/normas
18.
Circ Res ; 105(9): 876-85, 2009 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-19762679

RESUMEN

RATIONALE: Persistent atrial fibrillation (AF) has been associated with structural and electric remodeling and reduced contractile function. OBJECTIVE: To unravel mechanisms underlying reduced sarcoplasmic reticulum (SR) Ca(2+) release in persistent AF. METHODS: We studied cell shortening, membrane currents, and [Ca(2+)](i) in right atrial myocytes isolated from sheep with persistent AF (duration 129+/-39 days, N=16), compared to matched control animals (N=21). T-tubule density, ryanodine receptor (RyR) distribution, and local [Ca(2+)](i) transients were examined in confocal imaging. RESULTS: Myocyte shortening and underlying [Ca(2+)](i) transients were profoundly reduced in AF (by 54.8% and 62%, P<0.01). This reduced cell shortening could be corrected by increasing [Ca(2+)](i). SR Ca(2+) content was not different. Calculated fractional SR Ca(2+) release was reduced in AF (by 20.6%, P<0.05). Peak Ca(2+) current density was modestly decreased (by 23.9%, P<0.01). T-tubules were present in the control atrial myocytes at low density and strongly reduced in AF (by 45%, P<0.01), whereas the regular distribution of RyR was unchanged. Synchrony of SR Ca(2+) release in AF was significantly reduced with increased areas of delayed Ca(2+) release. Propagation between RyR was unaffected but Ca(2+) release at subsarcolemmal sites was reduced. Rate of Ca(2+) extrusion by Na(+)/Ca(2+) exchanger was increased. CONCLUSIONS: In persistent AF, reduced SR Ca(2+) release despite preserved SR Ca(2+) content is a major factor in contractile dysfunction. Fewer Ca(2+) channel-RyR couplings and reduced efficiency of the coupling at subsarcolemmal sites, possibly related to increased Na(+)/Ca(2+) exchanger, underlie the reduction in Ca(2+) release.


Asunto(s)
Fibrilación Atrial/metabolismo , Función del Atrio Derecho , Señalización del Calcio , Contracción Miocárdica , Miocitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo , Citoesqueleto de Actina/metabolismo , Animales , Fibrilación Atrial/patología , Fibrilación Atrial/fisiopatología , Canales de Calcio Tipo L/metabolismo , Modelos Animales de Enfermedad , Técnicas Electrofisiológicas Cardíacas , Femenino , Glucógeno/metabolismo , Atrios Cardíacos/metabolismo , Atrios Cardíacos/patología , Atrios Cardíacos/fisiopatología , Potenciales de la Membrana , Miocitos Cardíacos/ultraestructura , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Sarcolema/metabolismo , Retículo Sarcoplasmático/ultraestructura , Ovinos , Intercambiador de Sodio-Calcio/metabolismo , Factores de Tiempo
19.
Eur Heart J ; 28(2): 183-9, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17172281

RESUMEN

AIMS: Complex invasive electrophysiological procedures may result in high cumulative operator radiation exposure. Classical protection with lead aprons results in discomfort while radioprotection is still incomplete. This study evaluated the usefulness of a radiation protection cabin (RPC) that completely surrounds the operator. METHODS AND RESULTS: The evaluation was performed independently in two electrophysiology laboratories (E1-Leuven, Belgium; E2-Bordeaux, France), comparing operator radiation exposure using the RPC vs. a 0.5 mm lead-equivalent apron (total of 135 procedures). E1 used thermoluminiscent dosimeters (TLDs) placed at 16 positions in and out of the RPC and nine positions in and out of the apron. E2 used more sensitive electronic personal dosimeters (EPD), placed at waist and neck. The sensitivity thresholds of the TLDs and EPDs were 10-20 microSv and 1-1.5 microSv, respectively. All procedures could be performed unimpeded with the RPC. Median TLD dose values outside protected areas were in the range of 57-452 microSv, whereas doses under the apron or inside the RPC were all at the background radiation level, irrespective of procedure and fluoroscopy duration and of radiation energy delivered. In addition, the RPC was protecting the entire body (except the hands), whereas lead apron protection is incomplete. Also with the more sensitive EPDs, the radiation dose within the RPC was at the sensitivity threshold/background level (1.3+/-0.6 microSv). Again, radiation to the head was significantly lower within the RPC (1.9+/-1.2 microSv) than with the apron (102+/-23 microSv, P<0.001). CONCLUSION: The use of the RPC allows performing catheter ablation procedures without compromising catheter manipulation, and with negligible radiation exposure for the operator.


Asunto(s)
Ablación por Catéter , Técnicas Electrofisiológicas Cardíacas/instrumentación , Protección Radiológica/instrumentación , Arritmias Cardíacas/terapia , Índice de Masa Corporal , Diseño de Equipo , Humanos , Radiometría
20.
Circulation ; 112(24): 3769-76, 2005 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-16330683

RESUMEN

BACKGROUND: Modern nonfluoroscopic mapping systems construct 3D electroanatomic maps by tracking intracardiac catheters. They require specialized catheters and/or dedicated hardware. We developed a new method for electroanatomic mapping by merging detailed 3D models of the endocardial cavities with fluoroscopic images without the need for specialized hardware. This developmental work focused on the right atrium because of the difficulties in visualizing its anatomic landmarks in 3D with current approaches. METHODS AND RESULTS: Cardiac MRI images were acquired in 39 patients referred for radiofrequency catheter ablation using balanced steady state free-precession sequences. We optimized acquisition and developed software for construction of detailed 3D models, after contouring of endocardial cavities with cross-checking of different imaging planes. 3D models were then merged with biplane fluoroscopic images by methods for image calibration and registration implemented in a custom software application. The feasibility and accuracy of this merging process were determined in heart-cast experiments and electroanatomic mapping in patients. Right atrial dimensions and relevant anatomic landmarks could be identified and measured in all 3D models. Cephalocaudal, posteroanterior, and lateroseptal diameters were, respectively, 65+/-11, 54+/-11, and 57+/-9 mm; posterior isthmus length was 26+/-6 mm; Eustachian valve height was 5+/-5 mm; and coronary sinus ostium height and width were 16+/-3 and 12+/-3 mm, respectively (n=39). The average alignment error was 0.2+/-0.3 mm in heart casts (n=40) and 1.9 to 2.5 mm in patient experiments (n=9), ie, acceptable for clinical use. In 11 patients, reliable catheter positioning and projection of activation times resulted in 3D electroanatomic maps with an unprecedented level of anatomic detail, which assisted ablation. CONCLUSIONS: This new approach allows activation visualization in a highly detailed 3D anatomic environment without the need for a specialized nonfluoroscopic mapping system.


Asunto(s)
Cateterismo Cardíaco/métodos , Ablación por Catéter/métodos , Diagnóstico por Imagen/métodos , Técnicas Electrofisiológicas Cardíacas/métodos , Corazón/anatomía & histología , Arritmias Cardíacas/terapia , Fluoroscopía/métodos , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Fantasmas de Imagen , Programas Informáticos , Resultado del Tratamiento
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