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1.
Cardiol Young ; 25(5): 893-902, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24983130

RESUMEN

OBJECTIVES: To evaluate long-term outcome of initial aortic valve intervention in a paediatric population with congenital aortic stenosis, and to determine risk factors associated with reintervention. PATIENTS AND METHODS: From 1985 to 2009, 77 patients with congenital aortic stenosis and a mean age of 5.8±5.6 years at diagnosis were followed up in our institution for 14.8±9.1 years. RESULTS: First intervention was successful with 86% of patients having a residual peak aortic gradient 1 regurgitation increased by 7%. Long-term survival after the first procedure was excellent, with 91% survival at 25 years. At a mean interval of 7.6±5.3 years, 30 patients required a reintervention (39%), mainly because of a recurrent aortic stenosis. Freedom from reintervention was 97, 89, 75, 53, and 42% at 1, 10, 15, 20, and 25 years, respectively. Predictors of reintervention were residual peak aortic gradient (p=0.0001), aortic regurgitation post-intervention >1 (p=0.02), prior balloon aortic valvuloplasty (p=0.04), and increased left ventricular posterior wall thickness (p=0.1). CONCLUSIONS: Aortic valve intervention is a safe and effective procedure for congenital aortic stenosis with excellent survival results. However, rate of reintervention is high and influenced by increased left ventricular posterior wall thickness pre-intervention, prior balloon valvuloplasty, higher residual peak systolic valve gradient, and more than mild regurgitation post-intervention. The study highlights that long-term follow-up is recommended for these patients.


Asunto(s)
Estenosis de la Válvula Aórtica/congénito , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Preescolar , Ecocardiografía , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Recurrencia , Reoperación , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento
2.
J Cardiovasc Electrophysiol ; 25(4): 418-427, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24383960

RESUMEN

INTRODUCTION: Paroxysmal atrial fibrillation (AF) may be triggered by intermittent atrial tachycardia, and ultimately lead to persistent AF. However, the mechanisms by which intermittent atrial tachycardia promotes sustained AF are not well understood. METHODS AND RESULTS: Eight sheep were chronically implanted with 2 pacemakers for the recording of broadband right atrial unipolar electrograms, and for the delivery of electrophysiological stimulation protocols and intermittent right atrial tachycardia. Right atrial kinetics of activation recovery interval (ARI) as a surrogate for action potential duration, of conduction time and velocity, and of repolarization alternans were analyzed at incremental pacing rates during the remodeling process induced by weeks of intermittent atrial tachycardia until the development of sustained AF. Intermittent atrial tachycardia decreased ARI and blunted its rate adaptation, facilitated atrial capture, and slowed conduction at high rates, and increased susceptibility to pacing-induced AF. In spite of blunted ARI rate adaptation, right atrial repolarization alternans was maintained during remodeling, and further increased in magnitude just before rapid pacing-induced AF. CONCLUSION: This study suggests that weeks of intermittent right atrial tachycardia result in a gradual electrical remodeling favorable for wavebreaks and reentry that may facilitate fibrillation.


Asunto(s)
Fibrilación Atrial/fisiopatología , Sistema de Conducción Cardíaco/fisiopatología , Taquicardia Atrial Ectópica/fisiopatología , Animales , Remodelación Atrial/fisiología , Estimulación Cardíaca Artificial , Modelos Animales de Enfermedad , Electrocardiografía , Cinética , Masculino , Periodo Refractario Electrofisiológico , Ovinos
3.
J Cardiovasc Electrophysiol ; 23(9): 1003-12, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22554055

RESUMEN

UNLABELLED: Kinetics of Atrial Repolarization Alternans. INTRODUCTION: Repolarization alternans (Re-ALT), a beat-to-beat alternation in action potential repolarization, promotes dispersion of repolarization, wavebreaks, and reentry. Recently, Re-ALT has been shown to play an important role in the transition from rapid pacing to atrial fibrillation (AF) in humans. The detailed kinetics of atrial Re-ALT, however, has not been reported so far. We developed a chronic free-behaving ovine pacing model to study the kinetics of atrial Re-ALT as a function of pacing rate. METHODS: Thirteen sheep were chronically implanted with 2 pacemakers for the recording of broadband right atrial unipolar electrograms and delivery of rapid pacing protocols. Beat-to-beat differences in the atrial T-wave apex amplitude as a measure of Re-ALT and activation time were analyzed at incremental pacing rates until the effective refractory period (ERP) defined as stable 2:1 capture. RESULTS: Atrial Re-ALT appeared intermittently but without periodicity, and increased in amplitude as a function of pacing rate until ERP. Intermittent 2:1 atrial capture was observed at pacing cycle lengths 40 ms above ERP, and increased in duration as a function of pacing rate. Episodes of rapid pacing-induced AF were rare, and were preceded by Re-ALT or complex oscillations of atrial repolarization, but without intermittent capture. CONCLUSION: We show in vivo that atrial Re-ALT developed and increased in magnitude with rate until stable 2:1 capture. In rare instances where capture failure did not occur, Re-ALT and complex oscillations of repolarization surged and preceded AF initiation. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1003-1012, September 2012).


Asunto(s)
Fibrilación Atrial/fisiopatología , Atrios Cardíacos/fisiopatología , Potenciales de Acción , Animales , Estimulación Cardíaca Artificial , Cinética , Masculino , Modelos Animales , Periodo Refractario Electrofisiológico , Ovinos
4.
J Heart Valve Dis ; 21(5): 584-90, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23167222

RESUMEN

BACKGROUND AND AIM OF THE STUDY: In aortic valve surgery, the management of ascending aortic dilatation is not clearly defined. Guidelines recommend replacement at diameters of 50 mm, but the handling of borderline dilatation has not been detailed. Reduction aortoplasty has been proposed as a less invasive and safe option in the case of a smaller dilatation above the sinotubular junction. METHODS: Between 1999 and 2009, reduction aortoplasties with or without external reinforcement associated with aortic valve surgery were performed in 82 patients. The ascending aortic diameter was measured echocardiographically at a mean follow up (FU) of 32 months (FU was 91% complete). RESULTS: The in-hospital mortality was 1.2%, and all patients were in NYHA class I or II. Echocardiography revealed a re-dilatation (> or = 5 mm) rate of 5.5%. One patient required reoperation. At univariate analysis, a preoperative dilatation >45 mm, persistent postoperative diameters >35 mm after reduction, and a younger age at the time of surgery (<65 years) were significant risk factors. Multivariate analysis confirmed the parameters for re-dilatation, and the area under the receiver operating curve was 0.85 for these three criteria. Mesh implantation, FU duration and bicuspid valve had no significant impact on outcome. CONCLUSION: Reduction aortoplasty is a less-invasive option to handle borderline supra-coronary aneurysms in the case of concomitant valve surgery, compared to aortic replacement. The mortality remained low, and equal to that for simple aortic valve replacement. A large preoperative aortic diameter and age < or = 65 years favored re-dilatation. Correct downsizing was technically demanding, but indispensable for long-term stabilization. Regard for these criteria could lead to numerous patients benefiting from this operative strategy, with good results.


Asunto(s)
Enfermedades de la Aorta/cirugía , Procedimientos Quirúrgicos Cardiovasculares , Adulto , Anciano , Anciano de 80 o más Años , Aorta/cirugía , Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/patología , Aneurisma de la Aorta/cirugía , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/patología , Dilatación Patológica/diagnóstico por imagen , Dilatación Patológica/patología , Dilatación Patológica/cirugía , Ecocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Periodo Posoperatorio , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
6.
Heart Lung Circ ; 20(10): 663-5, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21478051

RESUMEN

We report an unusual case of congenital giant coronary aneurysm. A 23 year-old male with a history of acute myocardial infarction presented an abnormal shadow in the left cardiac border on routine X-ray. Electrocardiogram and physical examination were normal without any clinical signs of inflammation, but computed tomography (CT) scan and cardiac magnetic resonance imaging (MRI) revealed a giant (>50mm) coronary aneurysm. Coronary artery bypass grafting (CABG) with coronary artery aneurysm (CAA) resection resolved the CAA. Coronary artery aneurysms are entities of localised dilation and can be common events in chronic infectious disease as a result of the systemic inflammatory state; however, giant coronary aneurysms (measuring more than 50mm) are rare. This is especially true where the pathological aetiology was not clearly defined or was believed to be of congenital origin. To date only a few published case reports exist for this type of pathological entity.


Asunto(s)
Aneurisma Coronario/congénito , Aneurisma Coronario/diagnóstico por imagen , Adulto , Aneurisma Coronario/fisiopatología , Electrocardiografía , Humanos , Angiografía por Resonancia Magnética , Masculino , Infarto del Miocardio/psicología , Infarto del Miocardio/radioterapia , Infarto del Miocardio/terapia , Tomografía Computarizada por Rayos X
7.
Circ Res ; 99(4): 407-14, 2006 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-16857961

RESUMEN

The cardiac sodium channel Na(v)1.5 plays a key role in cardiac excitability and conduction. The purpose of this study was to elucidate the role of the PDZ domain-binding motif formed by the last three residues (Ser-Ile-Val) of the Na(v)1.5 C-terminus. Pull-down experiments were performed using Na(v)1.5 C-terminus fusion proteins and human or mouse heart protein extracts, combined with mass spectrometry analysis. These experiments revealed that the C-terminus associates with dystrophin, and that this interaction was mediated by alpha- and beta-syntrophin proteins. Truncation of the PDZ domain-binding motif abolished the interaction. We used dystrophin-deficient mdx(5cv) mice to study the role of this protein complex in Na(v)1.5 function. Western blot experiments revealed a 50% decrease in the Na(v)1.5 protein levels in mdx(5cv) hearts, whereas Na(v)1.5 mRNA levels were unchanged. Patch-clamp experiments showed a 29% decrease of sodium current in isolated mdx(5cv) cardiomyocytes. Finally, ECG measurements of the mdx(5cv) mice exhibited a 19% reduction in the P wave amplitude, and an 18% increase of the QRS complex duration, compared with controls. These results indicate that the dystrophin protein complex is required for the proper expression and function of Na(v)1.5. In the absence of dystrophin, decreased sodium current may explain the alterations in cardiac conduction observed in patients with dystrophinopathies.


Asunto(s)
Corazón/fisiología , Células Musculares/fisiología , Proteínas Musculares/fisiología , Canales de Sodio/fisiología , Animales , Clonación Molecular , ADN Complementario/genética , Distrofina/fisiología , Proteínas Asociadas a la Distrofina/fisiología , Electrocardiografía , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Células Musculares/citología , Proteínas Musculares/genética , Canal de Sodio Activado por Voltaje NAV1.5 , Técnicas de Placa-Clamp , Proteínas Recombinantes de Fusión/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Canales de Sodio/genética
8.
Europace ; 9 Suppl 6: vi71-6, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17959696

RESUMEN

AIMS: Surgical ablation procedures for treating atrial fibrillation have been shown to be highly successful. However, the ideal ablation pattern still remains to be determined. This article reports on a systematic study of the effectiveness of the performance of different ablation line patterns. METHODS AND RESULTS: This study of ablation line patterns was performed in a biophysical model of human atria by combining basic lines: (i) in the right atrium: isthmus line, line between vena cavae and appendage line and (ii) in the left atrium: several versions of pulmonary vein isolation, connection of pulmonary veins, isthmus line, and appendage line. Success rates and the presence of residual atrial flutter were documented. Basic patterns yielded conversion rates of only 10-25 and 10-55% in the right and the left atria, respectively. The best result for pulmonary vein isolation was obtained when a single closed line encompassed all veins (55%). Combination of lines in the right/left atrium only led to a success rate of 65/80%. Higher rates, up to 90-100%, could be obtained if right and left lines were combined. The inclusion of a left isthmus line was found to be essential for avoiding uncommon left atrial flutter. CONCLUSION: Some patterns studied achieved a high conversion rate, although using a smaller number of lines than those of the Maze III procedure. The biophysical atrial model is shown to be effective in the search for promising alternative ablation strategies.


Asunto(s)
Fibrilación Atrial/cirugía , Ablación por Catéter/métodos , Fibrilación Atrial/patología , Fibrilación Atrial/fisiopatología , Aleteo Atrial/prevención & control , Fenómenos Biofísicos , Biofisica , Sistema de Conducción Cardíaco/patología , Sistema de Conducción Cardíaco/fisiopatología , Sistema de Conducción Cardíaco/cirugía , Humanos , Modelos Cardiovasculares , Resultado del Tratamiento
9.
Europace ; 9 Suppl 6: vi83-8, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17959698

RESUMEN

AIMS: Experimental models have reported conflicting results regarding the role of dispersion of repolarization in promoting atrial fibrillation (AF). Repolarization alternans, a beat-to-beat alternation in action potential duration, enhances dispersion of repolarization when propagation velocity is involved. METHODS AND RESULTS: In this work, original electrophysiological parameters were analysed to study AF susceptibility in a chronic sheep model of pacing-induced AF. Two pacemakers were implanted, each with a single right atrial lead. Right atrial depolarization and repolarization waves were documented at 2-week intervals. A significant and gradual decrease in the propagation velocity at all pacing rates and in the right atrial effective refractory period (ERP) was observed during the weeks of burst pacing before sustained AF developed when compared with baseline conditions. Right atrial repolarization alternans was observed, but because of the development of 2/1 atrioventricular block with far-field ventricular interference, its threshold could not be precisely measured. Non-sustained AF was not observed at baseline, but appeared during the electrical remodelling in association with a decrease in both ERP and propagation velocity. CONCLUSION: We report here on the feasibility of measuring ERP, atrial repolarization alternans, and propagation velocity kinetics and their potential in predicting susceptibility to AF in a free-behaving model of pacing-induced AF using the standard pacemaker technology.


Asunto(s)
Fibrilación Atrial/etiología , Fibrilación Atrial/fisiopatología , Estimulación Cardíaca Artificial , Modelos Animales de Enfermedad , Potenciales de Acción/fisiología , Animales , Sistema de Conducción Cardíaco/fisiopatología , Cinética , Conducción Nerviosa/fisiología , Marcapaso Artificial , Ovinos
10.
Eur J Cardiothorac Surg ; 32(2): 301-7, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17561410

RESUMEN

OBJECTIVE: Mitral valve repair is the gold standard to restore mitral valve function and is now known to have good long-term outcome. In order to help perioperative decision making, we analyzed our collective to find independent risk factors affecting their outcome. METHODS: We retrospectively studied our first 175 consecutive adult patients (mean age: 64+/-10.4 years; 113 males) who underwent primary mitral valve repair associated with any other cardiac procedures between January 1986 and December 1998. Risk factors influencing reoperations and late survival were plotted in a uni- and multivariate analyses. RESULTS: Operative mortality was 3.4% (6 deaths, 0-22nd postoperative day (POD)). Late mortality was 9.1% (16 deaths, 3rd-125th POM). Reoperation was required in five patients. Kaplan-Meier actuarial analysis demonstrated a 96+/-1% 1-year survival, 88+/-3% 5-year survival and a 69+/-8% 10-year survival. Freedom from reoperations was 99% at 1 year after repair, 97+/-2% after 5 years and 88+/-6% after 10 years. Multivariate analysis demonstrated that residual NYHA class III and IV (p=0.001, RR 4.55, 95% CI: 1.85-14.29), poor preoperative ejection fraction (p=0.013, RR 1.09, 95% CI: 1.02-1.18), functional MR (p=0.018, RR 4.17, 95% CI: 1.32-16.67), and ischemic MR (p=0.049, RR 3.13, 95% CI: 1.01-10.0) were all independent predictors of late death. Persistent mitral regurgitation at seventh POD (p=0.005, RR 4.55, 95% CI: 1.56-20.0), age below 60 (p=0.012, RR 8.7, 95% CI: 2.44-37.8), and absence of prosthetic ring (p=0.034, RR 4.76, 95% CI: 1.79-33.3) were all independent risk factors for reoperation. CONCLUSIONS: Mitral valve repair provides excellent survival. However, long-term outcome can be negatively influenced by perioperative risk factors. Risk of reoperation is higher in younger patients with a residual mitral regurgitation and without ring annuloplasty.


Asunto(s)
Insuficiencia de la Válvula Mitral/cirugía , Válvula Mitral/cirugía , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos Cardíacos/métodos , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/etiología , Insuficiencia de la Válvula Mitral/mortalidad , Complicaciones Posoperatorias , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
11.
Eur J Cardiothorac Surg ; 31(1): 65-9, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17081766

RESUMEN

OBJECTIVE: The surgical Maze III procedure remains the gold standard in treating atrial fibrillation (AF); however due to clinical difficulties and higher risks, less invasive ablation alternatives are clinically investigated. The present study aims to define more efficient ablation patterns of the modified maze procedure using a biophysical model of human atria with chronic AF. METHODS: A three-dimensional model of human atria was developed using both MRI-imaging and a one-layer cellular model reproducing experimentally observed atrial cellular properties. Sustained AF could be induced by a burst-pacing protocol. Ablation lines were implemented in rendering the cardiac cells non-conductive, mimicking transmural lines. Lines were progressively implemented respectively around pulmonary veins (PV), left atrial appendage (LAA), left atrial isthmus (LAI), cavo-tricuspid isthmus (CTI), and intercaval lines (SIVC) in the computer model, defining the following patterns: P1=PV, P2=P1+LAA, P3=P2+LAI, P4=P3+CTI, P5=P3+SIVC, P6=P5+CTI. Forty simulations were done for each pattern and proportion of sinus rhythm (SR) conversion and time-to-AF termination (TAFT) were assessed. RESULTS: The most efficient patterns are P5, P6, and Maze III with 100% success. The main difference is expressed in decreasing mean TAFT with a correlation coefficient R=-0.8. There is an inflexion point for 100% success rate at a 7.5s TAFT, meaning that no additional line is mandatory beyond pattern P5. CONCLUSIONS: Our biophysical model suggests that Maze III could be simplified in his right atrial pattern to a single line joining both vena cavae. This has to be confirmed in clinical settings.


Asunto(s)
Fibrilación Atrial/fisiopatología , Fibrilación Atrial/cirugía , Ablación por Catéter/métodos , Modelos Cardiovasculares , Simulación por Computador , Electrofisiología , Atrios Cardíacos/fisiopatología , Sistema de Conducción Cardíaco/fisiopatología , Humanos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética
12.
Eur J Cardiothorac Surg ; 32(1): 90-5, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17420135

RESUMEN

OBJECTIVE: To determine the adequacy of 'in silico' biophysical models of atrial fibrillation (AF) in the design of different ablation line patterns. BACKGROUND: Permanent AF is a severe medical problem for which (surgical) ablation is a possible treatment. The ideal ablation pattern remains to be defined. METHODS: Forty-six consecutive adult patients with symptomatic permanent drug refractory AF underwent mitral surgery combined with non-transmural, (n=20) and transmural (n=26) radiofrequency Minimaze. The fraction of 'in vivo' conversions to sinus rhythm (SR) in both groups was compared with the performance of the fraction of 'in silico' conversions observed in a biophysical model of permanent AF. The simulations allowed us to study the effectiveness of incomplete and complete ablation patterns. A simulated, complete, transmural Maze III ablation pattern was applied to 118 different episodes of simulated AF set-up in the model and its effectiveness was compared with the clinical results reported by Cox. RESULTS: The fraction of conversions to SR was 92% 'in vivo' and 88% 'in silico' (p=ns) for transmural/complete ablations, 60% respectively 65% for non-transmural/incomplete Minimaze (p=ns) and 98% respectively 100% for Maze III ablations (p=ns). The fraction of conversions to SR 'in silico' correlated with the rates 'in vivo' (r2=0.973). CONCLUSIONS: The fraction of conversions to SR observed in the model closely corresponded to the conversion rate to SR post-surgery. This suggests that the model provides an additional, non-invasive tool for optimizing ablation line patterns for treating permanent AF.


Asunto(s)
Fibrilación Atrial/cirugía , Ablación por Catéter/métodos , Modelos Cardiovasculares , Anciano , Fibrilación Atrial/patología , Femenino , Atrios Cardíacos/patología , Atrios Cardíacos/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
13.
Arch Cardiovasc Dis ; 110(6-7): 389-394, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28433509

RESUMEN

BACKGROUND: Transcarotid access is an alternative route for transcutaneous aortic valve implantation (TAVI) in patients with impossible transfemoral access. AIMS: We evaluated the safety, effectiveness and early and late clinical outcomes of CoreValve® implantation via the common carotid artery. METHODS: Eighteen patients (10 men, 8 women; mean age 84±5 years) at high surgical risk (mean EuroSCORE II 16±13%) with significant peripheral artery disease underwent TAVI via common carotid artery access under general anaesthesia. Mean aortic valve area was 0.64±0.13cm2 (0.36±0.07cm2/m2). RESULTS: At a mean follow-up of 605±352 days, two patients (11%) had died in hospital, on days 6 and 20, as a result of sepsis with multiorgan failure (n=1) or pneumonia (n=1). There were no perioperative deaths, myocardial infarctions or strokes. Perioperative prosthesis embolization occurred in one patient (6%), requiring implantation of a second valve. In-hospital complications occurred in four patients (23%): blood transfusion for transient significant bleeding at the access site in one patient (6%); permanent pacemaker implantation in two patients (11%); and pericardial drainage in one patient (6%). The rate of event-free in-hospital stay was 66%. Post-procedural echocardiography showed very good haemodynamic performance, with a mean gradient of 8±3mmHg. Moderate paravalvular leak was present in one patient (6%). Mean intensive care unit stay was 48±31h; mean in-hospital stay was 7±3 days. CONCLUSION: TAVI performed by transcarotid access in this small series of severely ill patients was associated with a low incidence of complications, which were associated with the procedure itself rather than the access route.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Arteria Carótida Común , Enfermedad Arterial Periférica/complicaciones , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Anciano , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/fisiopatología , Arteria Carótida Común/diagnóstico por imagen , Supervivencia sin Enfermedad , Estudios de Factibilidad , Femenino , Arteria Femoral/diagnóstico por imagen , Prótesis Valvulares Cardíacas , Hemodinámica , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Masculino , Enfermedad Arterial Periférica/diagnóstico por imagen , Estudios Prospectivos , Diseño de Prótesis , Recuperación de la Función , Factores de Tiempo , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Reemplazo de la Válvula Aórtica Transcatéter/mortalidad , Resultado del Tratamiento
14.
JACC Basic Transl Sci ; 1(6): 472-493, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29707678

RESUMEN

The mechanisms controlling differentiation in adult cardiac precursor cells (CPCs) are still largely unknown. In this study, CPCs isolated from the human heart were found to produce predominantly smooth muscle cells but could be redirected to the cardiomyocyte fate by transient activation followed by inhibition of NOTCH signaling. NOTCH inhibition repressed MIR-143/145 expression, and blocked smooth muscle differentiation. Expression of the microRNAs is under control of CARMEN, a long noncoding RNA associated with an enhancer located in the MIR-143/145 locus and target of NOTCH signaling. The CARMEN/MIR-145/143 axis represents, therefore, a promising target to favor production of cardiomyocytes in cell replacement therapies.

15.
Stroke ; 36(1): 21-6, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15576656

RESUMEN

BACKGROUND AND PURPOSE: Hyperperfusion syndrome (HS) after carotid endarterectomy (CEA) has been related to impaired cerebrovascular autoregulation in a chronically hypoperfused hemisphere. Our aim was to provide new insight into the pathophysiology of the HS using magnetic resonance imaging (MRI) studies with diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI). METHODS: Five out of 388 consecutive patients presented 2 to 7 days after CEA, partial seizures (n=5), focal deficits (n=5), and intracerebral hemorrhage (n=3). In 4 patients, using sequential examinations, we identified vasogenic or cytotoxic edema by DWI; we assessed relative interhemispheric difference (RID) of cerebral blood flow (CBF) by PWI; and we measured middle cerebral artery mean flow velocities (MCA Vm) by transcranial Doppler (TCD). RESULTS: None of the patients presented pathological DWI hyperintensities, consistent with the absence of acute ischemia or cytotoxic edema. In 2 patients, we found an MRI pattern of reversible vasogenic edema similar to that observed in the posterior leukoencephalopathy syndrome. Middle cerebral artery (MCA) mean flow velocities (Vm) were not abnormally increased at any time. PWI documented a 20% to 44% RID of CBF in favor of the ipsilateral to CEA hemisphere. CONCLUSIONS: HS can occur in the presence of moderate relative hyperperfusion of the ipsilateral hemisphere. MCA Vm values may not accurately reflect RID of CBF over the cortical convexity. We suggest that the hemodynamic pathogenetic mechanisms of the HS are more complicated than hitherto believed and that they may be more accurately described by the term "reperfusion syndrome."


Asunto(s)
Trastornos Cerebrovasculares/etiología , Endarterectomía Carotidea , Daño por Reperfusión/etiología , Anciano , Hemorragia Cerebral/etiología , Circulación Cerebrovascular , Trastornos Cerebrovasculares/diagnóstico , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Angiografía por Resonancia Magnética , Masculino , Daño por Reperfusión/diagnóstico , Convulsiones/etiología , Síndrome , Tomografía Computarizada por Rayos X , Ultrasonografía Doppler Transcraneal
16.
J Cereb Blood Flow Metab ; 24(8): 860-8, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15362716

RESUMEN

High-intensity transient signals (HITS) detected by transcranial Doppler (TCD) ultrasound may correspond to artifacts or to microembolic signals, the latter being either solid or gaseous emboli. The goal of this study was to assess what can be achieved with an automatic signal processing system for artifact/microembolic signals and solid/gas differentiation in different clinical situations. The authors studied 3,428 HITS in vivo in a multicenter study, i.e., 1,608 artifacts in healthy subjects, 649 solid emboli in stroke patients with a carotid stenosis, and 1,171 gaseous emboli in stroke patients with patent foramen ovale. They worked with the dual-gate TCD combined to three types of statistical classifiers: binary decision trees (BDT), artificial neural networks (ANN), and support vector machines (SVM). The sensitivity and specificity to separate artifacts from microembolic signals by BDT reached was 94% and 97%, respectively. For the discrimination between solid and gaseous emboli, the classifier achieved a sensitivity and specificity of 81% and 81% for BDT, 84% and 84% for ANN, and 86% and 86% for SVM, respectively. The current results for artifact elimination and solid/gas differentiation are already useful to extract data for future prospective clinical studies.


Asunto(s)
Artefactos , Embolia Aérea/diagnóstico por imagen , Embolia Intracraneal/diagnóstico por imagen , Algoritmos , Estenosis Carotídea/complicaciones , Circulación Cerebrovascular/fisiología , Árboles de Decisión , Defectos del Tabique Interatrial/complicaciones , Humanos , Embolia Intracraneal/etiología , Redes Neurales de la Computación , Sensibilidad y Especificidad , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Ultrasonografía Doppler Transcraneal
17.
Eur J Cardiothorac Surg ; 26 Suppl 1: S14-7; discussion S17-8, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15776843

RESUMEN

The advent of stents has profoundly changed percutaneous transluminal coronary angioplasty (PTCA), peripheral transluminal artery angioplasty (PTA), and treatment strategies of numerous other problems. Similar developments can be observed for stent applications in peripheral vascular lesions, cerebro-vascular disease, and many other fields. With the advent of covered stent-grafts, aneurysm surgery, has been put up for competitive treatment approaches. Such new approaches are perceived as less invasive, and draw significant attention. Endovsacular aneurysm repair (EVAR) is here to stay. In addition new developments are coming in many ways and stent derived devices can by now be found everywhere in the cardio-vascular system. This includes stenosed vessels, aneurysmal vessels, diseased valves, all sorts of congenital heart defects, and even cardiopulmonary bypass. The key technologies and know-how for EVAR are available or can be made available in most cardio-vascular surgical units. Special interest in this field (clinical and/or experimental) can enhance recruitment of patients. The opposite is also true...


Asunto(s)
Aneurisma de la Aorta/cirugía , Disección Aórtica/cirugía , Stents , Humanos , Stents/tendencias
18.
Eur J Cardiothorac Surg ; 25(5): 754-9, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15082278

RESUMEN

OBJECTIVE: The aim of the present study is to evaluate a new self-expanding valved stent design for minimal invasive aortic valve implantation and its interference with coronary flow. METHODS: An equine pericardial valve mounted onto a self-expanding nitinol stent (3F Therapeutics trade mark, CA, USA), outer diameter 23 mm, was evaluated (A) in vitro in a dynamic pulsatile mock loop and (B) in vivo in six calves (75+/-2.5 kg). In four animals valve stents were implanted on-pump and in two animals off-pump after induction of ventricular fibrillation. Target site for deployment was the orthotopic aorta, over the native valves. In vivo assessment was performed with intracardiac (AcuNav) and intravascular ultrasound including leaflet motion, planimetric valve orifice and residual-coronary\sinus-stent-index (RCSSI, distance stent to aortic wall/coronary diameter) calculations, coronary blood flow characteristics, transvalvular gradient, regurgitation and paravalvular leaking, in combination with continuous cardiac output measures. Macroscopic analysis was performed at necropsy. RESULTS: Two-dimensional intracardiac ultrasound showed good leaflet motion, with full valvular opening and closing in five of six valves. Planimetric valve orifice was 1.75+/-0.4 cm(2). There were no signs of coronary flow impairment with an RCSSI of 1.8+/-1.2. The implanted valved stents showed a low transvalvular gradient of 5.3+/-3.9 mmHg (mean, peak-to-peak) on invasive measurements and 4.7+/-2.5 mmHg in two-dimensional intracardiac sonography. One of six valves showed mild to moderate regurgitation and one of six valves a minor to moderate paravalvular leak due to size mismatch. CONCLUSIONS: This new self-expanding valved stent design allows for on- and off-pump aortic valve implantation in the orthotopic aorta, over the native valves without interference of the coronary blood flow and excellent acute valve function in properly sized devices.


Asunto(s)
Válvula Aórtica/cirugía , Circulación Coronaria , Prótesis Valvulares Cardíacas , Stents , Animales , Válvula Aórtica/diagnóstico por imagen , Bovinos , Vasos Coronarios/diagnóstico por imagen , Ecocardiografía/métodos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Diseño de Prótesis
19.
Eur J Cardiothorac Surg ; 26(3): 614-20, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15302059

RESUMEN

OBJECTIVE: Determine the usefulness of endovascular surgery for repair of aortic lesions late after open surgical repair. PATIENTS AND METHODS: A retrospective analysis of our databank (Patient Analysis and Tracking System, Dendrite, UK) for 2000-2002 showed 286 descending thoracic and/or abdominal aortic aneurysms: 60/286 (21%) descending thoracic, and 255/286 abdominal (89%). Endovascular surgery was planned in 98 patients (17/60 (28%) for thoracic lesions, and 81/255 (32%) for abdominal lesions). 13/98 patients (13%) underwent endovascular surgery late after failed open aortic repair: 4/13 at the level of distal aortic arch (3/4 for false aneurysms post-coarctation repair), 4/13 at the level of the descending thoracic aorta (3/4 for false aneurysms proximal to the previous graft), and 5/13 at the level of the infrarenal abdominal aorta (4/5 for false aneurysms proximal to the previous graft). Endovascular surgery included per procedural target site identification (previous graft) with intravascular ultrasound (IVUS) under fluoroscopic control (no angiographies), controlled hypotension (partial inflow occlusion with a right atrial balloon introduced through a femoral vein) for unloading of covered endoprostheses in the thoracic aorta, as well as in situ introducer sheath dilatation in case of complex access to the aorta. RESULTS: There were no hospital deaths and no parapareses or paraplegias in this small series of patients who underwent endovascular surgery for aneurismal lesions occurring late after open repair. An endoleak type I was documented in 2/13 patients (15%) requiring a proximal extension in 1 patient. For the second patient with a minor endoleak, a control examination is planned at 6 months of follow-up. CONCLUSION: Endovascular surgery is an elegant approach for repair of recurring aortic lesions late after open aortic surgery. IVUS is a precious instrument for per procedural identification of the previous implants. However, long-term follow-up is mandatory after endovascular surgery.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/métodos , Adulto , Anciano , Aneurisma Falso/cirugía , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Femenino , Fluoroscopía , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos , Reoperación , Estudios Retrospectivos , Ultrasonografía Intervencional
20.
Ann Thorac Surg ; 97(4): e111-3, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24694451

RESUMEN

Immunoglobulin G4 (IgG4)-related fibroinflammatory systemic disease accounts for 7% of all noninfectious aneurysms of the thoracic aorta. A patient was admitted with a symptomatic ascending aortic aneurysm and thickened aortic wall (outer/inner diameter 55/45 mm), which was replaced. Probes revealed IgG4-related aortitis associated with a primary tuberculosis infection. Corticosteroid and antituberculosis therapies were used, and the patient's clinical evolution was favorable. The optimal treatment strategy of IgG4-related aortitis, a new entity, remains vague. Inner aortic diameter alone does not justify aortic replacement, but wall thickening may mimic intramural hematoma. In this particular case of IgG4-related aortitis, immunosuppressive treatment alone, as an alternative to a surgical procedure, may be debatable.


Asunto(s)
Aorta/cirugía , Aortitis/inmunología , Aortitis/cirugía , Inmunoglobulina G , Femenino , Humanos , Persona de Mediana Edad
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