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1.
Respiration ; : 1-16, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39378862

RESUMEN

INTRODUCTION: Patent foramen ovale (PFO) affects about 25% of the population. We studied outcomes in cystic fibrosis (CF). METHODS: We conducted a case-control study of patients with CF (PwCF) and age and sex-matched controls who underwent agitated saline contrast (bubble) echocardiography, 1998-2020. We assessed PFO impacts using linear, logistic, quasipoisson and proportional hazards models. RESULT: 59 of 64 PwCF and 88 of 93 controls underwent bubble studies to investigate unexplained hypoxemia or dyspnea. PwCF had higher mean pulmonary artery pressure (PAP, 6.9 mm Hg, 95% Confidence Interval [CI] = 2.35-11.4), reduced tricuspid annular plane systolic excursion (TAPSE, -3.78 mm, CI = -5.64 to -1.93) and similar right ventricular diastolic sizes. Absent hypoxemia, PFO incidence was similar between PwCF and controls; with hypoxemia, PFO was more common in CF (Odds Ratio [OR] = 5.00, CI = 1.32-19.0). In CF, oxygen supplementation occurred at a percent predicted forced expiratory volume in 1 s (FEV1%) 22.5 points higher with PFO. Adjusted for FEV1%, PFO was associated with 0.59 more prior year pulmonary exacerbations (CI = 0.20-0.98) and shorter time to next exacerbation (Hazard Ratio = 1.86, CI = 1.06-3.26). Associations between PFO and hypoxemia or exacerbations were insensitive to PAP, TAPSE and CF transmembrane regulator protein modulator treatments. PFO was not associated with CF time to death or lung transplantation (median 1.87 years) adjusted for age, sex, FEV1% and prior year exacerbation counts. CONCLUSION: PFO in CF is associated with hypoxemia at higher FEV1% and more pulmonary exacerbations but not survival.

2.
Catheter Cardiovasc Interv ; 98(7): 1275-1284, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33682308

RESUMEN

OBJECTIVE: To identify predictors of 30-day all-cause mortality for patients with cardiogenic shock secondary to acute coronary syndrome (ACS-CS) who require short-term mechanical circulatory support (ST-MCS). BACKGROUND: ACS-CS mortality is high. ST-MCS is an attractive treatment option for hemodynamic support and stabilization of deteriorating patients. Mortality prediction modeling for ACS-CS patients requiring ST-MCS has not been well-defined. METHODS: The Utah Cardiac Recovery (UCAR) Shock database was used to identify patients admitted with ACS-CS requiring ST-MCS devices between May 2008 and August 2018. Pre-ST-MCS clinical, laboratory, echocardiographic, and angiographic data were collected. The primary endpoint was 30-day all-cause mortality. A weighted score comprising of pre-ST-MCS variables independently associated with 30-day all-cause mortality was derived and internally validated. RESULTS: A total of 159 patients (mean age, 61 years; 78% male) were included. Thirty-day all-cause mortality was 49%. Multivariable analysis resulted in four independent predictors of 30-day all-cause mortality: age, lactate, SCAI CS classification, and acute kidney injury. The model had good calibration and discrimination (area under the receiver operating characteristics curve 0.80). A predictive score (ranging 0-4) comprised of age ≥ 60 years, pre-ST-MCS lactate ≥2.5 mmol/L, AKI at time of ST-MCS implementation, and SCAI CS stage E effectively risk stratified our patient population. CONCLUSION: The ACS-MCS score is a simple and practical predictive score to risk-stratify CS secondary to ACS patients based on their mortality risk. Effective mortality risk assessment for ACS-CS patients could have implications on patient selection for available therapeutic strategy options.


Asunto(s)
Corazón Auxiliar , Choque Cardiogénico , Femenino , Hemodinámica , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Choque Cardiogénico/diagnóstico , Choque Cardiogénico/etiología , Choque Cardiogénico/terapia , Resultado del Tratamiento
4.
Eur Heart J ; 36(35): 2373-80, 2015 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-26071599

RESUMEN

AIMS: Evidence from randomized controlled trials (RCTs) evaluating possible benefits of endovascular therapy (EVT) for acute ischaemic stroke has shown conflicting results. The purpose of this meta-analysis was to systematically examine clinical outcomes in RCTs comparing the use of intravenous (IV) fibrinolysis alone to IV fibrinolysis plus EVT, for the treatment of acute ischaemic stroke. METHODS AND RESULTS: We selected English language RCTs, comparing EVT plus IV tissue-type plasminogen activator (tPA) (if eligible) with IV tPA alone in eligible patients for the treatment of acute ischaemic stroke. The primary endpoint was good functional outcome [modified Rankin Scale (mRS) of 0-2]. Other major endpoints of interest were all-cause mortality and symptomatic intracerebral haemorrhage (sICH). The meta-analysis included 8 RCTs that randomized 2423 patients with large-vessel, anterior-circulation stroke. EVT significantly improved the rate of functional independence (90-day mRS of 0-2) when compared with IV fibrinolysis [odds ratio (OR) 1.73, 95% confidence interval (CI) 1.18-2.53, number needed to treat (NNT) = 9.3]. The all-cause mortality was lower with EVT compared with the control group; however, the result did not reach statistical significance (OR 0.89, 95% CI 0.68-1.15). The rate of sICH was not higher with EVT (OR 1.07, 95% CI 0.73-1.56). Analyses from only the recent trials (reported in 2014-15) showed further benefit (OR of mRS 0-2: 2.42, 95% CI 1.91-3.08, NNT = 5) with similar safety results. CONCLUSION: In centres with advanced systems of stroke care, EVT significantly improved functional outcomes (without compromising safety) in patients with acute ischaemic stroke due to anterior circulation, large artery occlusion, compared with standard therapy.


Asunto(s)
Procedimientos Endovasculares/métodos , Accidente Cerebrovascular/terapia , Fibrinolíticos/uso terapéutico , Humanos , Infusiones Intravenosas , Ensayos Clínicos Controlados Aleatorios como Asunto , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/uso terapéutico , Resultado del Tratamiento
6.
J Interv Card Electrophysiol ; 67(5): 915-917, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38684636

RESUMEN

Leadless pacemakers offer the opportunity to avoid transvenous hardware among patients with tricuspid valve prostheses. We present the first case of a helix-based fixation leadless pacemaker implanted through valve-in-valve tricuspid prostheses in a 43-year-old female with extensive prior cardiac history. At the time of presentation, epicardial pacing was no longer a viable option in the setting of pacemaker dependence. Placement of a helix-fixed, leadless right ventricular pacemaker was performed as a bridge to dual-chamber leadless pacing. This was safely and effectively performed and highlighted favorable procedural characteristics that included RV cavity dimensions and prosthesis type.


Asunto(s)
Prótesis Valvulares Cardíacas , Marcapaso Artificial , Válvula Tricúspide , Humanos , Femenino , Adulto , Válvula Tricúspide/cirugía , Válvula Tricúspide/diagnóstico por imagen , Implantación de Prótesis de Válvulas Cardíacas/métodos , Resultado del Tratamiento , Estimulación Cardíaca Artificial/métodos , Diseño de Prótesis
7.
Artículo en Inglés | MEDLINE | ID: mdl-38699658

RESUMEN

Background: D2 aortic stenosis (AS) is the highest risk AS subtype with worse operative and mortality outcomes. This study aimed to investigate the quality of life (QoL) and left ventricular ejection fraction (LVEF) in patients with classic (D2 subtype) low-flow/low-gradient AS who underwent transcatheter aortic valve replacement (TAVR). Methods: In total, 634 patients with severe AS underwent TAVR at our institution from 2014 to 2020, of whom 76 met criteria for classic D2 AS with reduced LVEF. Echocardiographic and clinical outcomes including mortality, stroke, pacemaker placement (PPM), and readmission at baseline were compared with those at 30 days and 1 year. QoL data were extracted from the Kansas City Cardiomyopathy Questionnaire (KCCQ-12). Results: The average baseline Society of Thoracic Surgeons risk score for patients with D2 AS was 7.66 ± 6.76. Patients with D2 AS reported improved QoL post-TAVR. The average baseline KCCQ-12 score was 39.5 ± 20, with improvement to 68.9 ± 20.6 at 30 days (P < .01) and 74.9 ± 17.5 at 1 year (P < .01). Mortality was 0% at 30 days and 18.4% at 1 year. The average baseline LVEF was 36.1 ± 9.4. Left ventricular function improved to 43.5 ± 12.9 (P <.001) at 30 days and 46.3 ± 11.2 (P = .03) at 1 year. Complications post-TAVR at 30 days included stroke (1.3%) and PPM (11.8%). Patients with D2 AS exhibited higher baseline conduction defects including atrial fibrillation and higher postoperative PPM than those with other subtypes. Conclusions: Patients with D2 AS had significantly improved LVEF and QoL following TAVR at 30 days and 1 year. Postoperative rates of new PPM were higher than other subtypes, while stroke, dialysis, and mortality were lower than expected, supporting the benefit of TAVR in this high-risk group.

8.
Catheter Cardiovasc Interv ; 80(6): 987-90, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22109970

RESUMEN

Mitral stenosis is associated with significant morbidity and mortality. Percutaneous balloon mitral valvuloplasty is a standard treatment option for severe mitral stenosis, and in some patients may be the only feasible option. In patients with suitable valve anatomy and morphology, and with requisite physician expertise the procedure has a high success rate and good long-term outcomes. Nonetheless, even in appropriately selected patients the procedure can pose significant technical challenges. The transeptal antegrade approach using the Inoue Balloon system may be associated with difficulty and rarely with failure to cross the stenotic mitral valve. We report a case of initial Inoue balloon failure to cross followed by successful Inoue mitral valvuloplasty tracked over an arteriovenous wire loop.


Asunto(s)
Valvuloplastia con Balón/instrumentación , Catéteres Cardíacos , Estenosis de la Válvula Mitral/terapia , Cardiopatía Reumática/terapia , Adulto , Ecocardiografía Transesofágica , Diseño de Equipo , Humanos , Masculino , Estenosis de la Válvula Mitral/diagnóstico por imagen , Cardiopatía Reumática/diagnóstico por imagen , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
9.
Cardiovasc Revasc Med ; 23: 91-93, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32680698

RESUMEN

We describe the patient selection, intraprocedural imaging, and procedural technique for transseptal puncture through the Gore® Cardioform interatrial septal occluder. Due to new indications for PFO closure and increasing need for access to the left atrium via percutaneous approach, we expect an increasing need for utilization of a trans-septal puncture technique through these devices.


Asunto(s)
Foramen Oval Permeable , Defectos del Tabique Interatrial , Dispositivo Oclusor Septal , Cateterismo Cardíaco/efectos adversos , Humanos , Punciones , Resultado del Tratamiento
10.
J Invasive Cardiol ; 33(1): E32-E39, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33385984

RESUMEN

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is now routinely performed in patients with aortic stenosis with low mortality and complication rates. Although periprocedural risks have been substantially minimized, procedure- and contrast-induced acute kidney injury (AKI) remains a major concern. AKI remains a frequent complication of contrast-guided interventional procedures and is associated with a significantly adverse prognosis. We review the currently available clinical data related to AKI, with emphasis on contrast-induced nephropathy (CIN), and discuss a novel, integrated approach aiming to minimize AKI risk in high-risk patients. A stepwise algorithm is also proposed for the management of these complex patients.


Asunto(s)
Lesión Renal Aguda , Estenosis de la Válvula Aórtica , Reemplazo de la Válvula Aórtica Transcatéter , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/epidemiología , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/cirugía , Humanos , Pronóstico , Factores de Riesgo , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos
11.
Expert Opin Emerg Drugs ; 15(2): 283-98, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20384546

RESUMEN

IMPORTANCE OF THE FIELD: Despite improved mortality and morbidity in the treatment of coronary artery disease, a significant proportion of patients will continue to experience recurrent angina pectoris. AREAS COVERED IN THIS REVIEW: Anti-anginal therapy has long been dominated by the use of beta-blockers, Ca(2+) channel blockers and nitrates. Most recently, ranolazine was introduced as a new anti-anginal class. This review article presents current and novel anti-anginal strategies under development. A discussion of their molecular mechanisms that may complement traditional therapies is presented. Medline and PubMed scientific search tools were primarily used to identify relevant literature dating from 1970 to 2008. WHAT THE READER WILL GAIN: This review provides a summary of both traditional and emerging therapeutic approaches to angina pectoris management. A discussion on the mechanism of action and clinical efficacy of ranolazine, trimetazidine, nicorandil, ivabradine, fasudil and growth factor gene therapy as anti-anginal agents is provided. TAKE HOME MESSAGE: The need for multiple approaches cannot be over-emphasized. Availability of various modalities would strongly enhance the ability to meet the needs of a heterogeneous patient population. Patients with recurrent angina pectoris most likely will require multi-drug regimen where different mechanisms may complement each other and result in a more efficacious strategy.


Asunto(s)
Angina de Pecho/tratamiento farmacológico , Fármacos Cardiovasculares/uso terapéutico , Drogas en Investigación/uso terapéutico , Angina de Pecho/genética , Angina de Pecho/metabolismo , Animales , Fármacos Cardiovasculares/efectos adversos , Drogas en Investigación/efectos adversos , Terapia Genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/genética , Recurrencia , Resultado del Tratamiento
12.
Curr Opin Cardiol ; 24(6): 591-5, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19752728

RESUMEN

PURPOSE OF REVIEW: Initial management of patients with stable ischemic heart disease (SIHD) continues to be vigorously debated amongst cardiologists. Despite the lack of robust data to support percutaneous coronary intervention (PCI) as the initial management of SIHD patients, it remains one of the most commonly performed procedures. Results of the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial reignited the controversy of the benefit of routine initial PCI over optimal medical therapy (OMT). RECENT FINDINGS: The trial suggested that, as an initial management strategy in patients with SIHD, PCI did not reduce the risk of death, myocardial infarction, or any other major cardiovascular events, when added to OMT. A meta-analysis from Schomig et al. suggests that a PCI-based invasive strategy may improve long-term survival compared with solely medical treatment in stable coronary artery disease patients. CONCLUSION: As the ability to mechanically dilate obstructive coronary arterial stenoses has vastly improved our approach to managing patients with SIHD, the result has been a swing from an initial pharmacologic approach. An improved understanding of the pathophysiology of acute coronary syndrome, increased insight into plaque and patient vulnerability has led to the more aggressive use of appropriately targeted pharmacologic agents and an evolution in what constitutes OMT, based largely on the results of the COURAGE trial. Recent studies support the concept that, in SIHD patients, OMT alone compares favorably with a therapeutic strategy combining OMT with mechanical intervention. Thus, the treatment pendulum may be swinging back to the understanding that 'best practice' today requires the judicious use of interventional and medical therapies in the appropriate patient population.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad de la Arteria Coronaria/terapia , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Humanos , Resultado del Tratamiento
13.
Hypertension ; 74(1): 208-215, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31055952

RESUMEN

Early detection of coronary artery dysfunction is of paramount cardiovascular clinical importance, but a noninvasive assessment is lacking. Indeed, the brachial artery flow-mediated dilation test only weakly correlated with acetylcholine-induced coronary artery function ( r=0.36). However, brachial artery flow-mediated dilation methodologies have, over time, substantially improved. This study sought to determine if updates to this technique have improved the relationship with coronary artery function and the noninvasive indication of coronary artery dysfunction. Coronary artery and brachial artery function were assessed in 28 patients referred for cardiac catheterization (61±11 years). Coronary artery function was determined by the change in artery diameter with a 1.82 µg/min intracoronary acetylcholine infusion. Based on the change in vessel diameter, patients were characterized as having dysfunctional coronary arteries (>5% vasoconstriction) or relatively functional coronary arteries (<5% vasoconstriction). Brachial artery function was determined by flow-mediated dilation, adhering to current guidelines. The acetylcholine-induced change in vessel diameter was smaller in patients with dysfunctional compared with relatively functional coronary arteries (-11.8±4.6% versus 5.8±9.8%, P<0.001). Consistent with this, brachial artery flow-mediated dilation was attenuated in patients with dysfunctional compared with relatively functional coronaries (2.9±1.9% versus 6.2±4.2%, P=0.007). Brachial artery flow-mediated dilation was strongly correlated with the acetylcholine-induced change in coronary artery diameter ( r=0.77, P<0.0001) and was a strong indicator of coronary artery dysfunction (receiver operator characteristic=78%). The current data support that updates to the brachial artery flow-mediated dilation technique have strengthened the relationship with coronary artery function, which may now provide a clinically meaningful indication of coronary artery dysfunction.


Asunto(s)
Acetilcolina/administración & dosificación , Arteria Braquial/efectos de los fármacos , Cateterismo Cardíaco/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Circulación Coronaria/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , Anciano , Arteria Braquial/fisiopatología , Estudios de Cohortes , Circulación Coronaria/fisiología , Vasos Coronarios/fisiopatología , Femenino , Humanos , Infusiones Intralesiones , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Medición de Riesgo , Vasoconstricción/efectos de los fármacos , Vasoconstricción/fisiología , Vasodilatación/efectos de los fármacos , Vasodilatación/fisiología
14.
Catheter Cardiovasc Interv ; 71(2): 191-6, 2008 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-18327836

RESUMEN

Myocardial bridge is the most common congenital coronary anomaly. Patients with this anomaly are usually asymptomatic, but it may cause myocardial ischemia that may lead to myocardial infarction. Treatment for myocardial bridge remains controversial. Current recommendations include medical therapy, surgical treatment (unroofing myotomy), coronary artery bypass, and percutaneous coronary stenting. We report two cases of stent fracture following stenting of a myocardial bridge. The risk of stent fracture leading to restenosis and/or stent thrombosis should be considered when assessing the risks and benefits of coronary revascularization of a myocardial bridge.


Asunto(s)
Puente Miocárdico/terapia , Falla de Prótesis , Stents , Adulto , Anciano , Angiografía Coronaria , Reestenosis Coronaria/epidemiología , Reestenosis Coronaria/prevención & control , Stents Liberadores de Fármacos , Femenino , Humanos , Masculino , Puente Miocárdico/complicaciones , Isquemia Miocárdica/etiología , Isquemia Miocárdica/terapia
16.
J Invasive Cardiol ; 29(1): E1-E7, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28045671

RESUMEN

Paravalvular leak (PVL) following aortic valve implantation is a rare complication but may cause potentially serious consequences. It occurs in 2%-10% of surgical aortic valve replacements and 7%-17% of surgical mitral valve replacements. Transcatheter valve replacement data show that significant PVL occurs in 6%-8% of cases. The management of significant PVL has traditionally involved repeat surgical repair. However, many of these patients are considered too high risk to undergo a repeat surgical procedure; hence, a percutaneous transcatheter approach has often been utilized to treat these patients. Vascular plugs have been used to close PVLs, with variable results; the procedure is complex and technically demanding. Transcatheter aortic valve replacement, using a valve-in-valve approach, may provide an alternative approach for bioprosthetic PVL in the aortic position.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Bioprótesis/efectos adversos , Prótesis Valvulares Cardíacas/efectos adversos , Anciano , Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/diagnóstico , Ecocardiografía , Humanos , Masculino , Falla de Prótesis , Reoperación , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos
17.
Tex Heart Inst J ; 44(5): 361-365, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29259512

RESUMEN

Coronary artery disease of the septal perforator branches can lead to clinical ischemia and conduction abnormalities. Performing interventional procedures in these vessels is frequently impossible because they are small, which makes it difficult to approach them and to select appropriate equipment. Larger septal perforator branches have been treated percutaneously in a few patients; however, the clinical effectiveness and long-term outcomes are not known. We present our experience in managing obstructive septal perforator branch stenosis in 4 patients.


Asunto(s)
Oclusión Coronaria/cirugía , Vasos Coronarios/cirugía , Tabiques Cardíacos , Intervención Coronaria Percutánea/métodos , Stents , Adulto , Anciano , Angiografía Coronaria , Oclusión Coronaria/diagnóstico , Vasos Coronarios/diagnóstico por imagen , Femenino , Humanos , Masculino
18.
EuroIntervention ; 13(7): 811-819, 2017 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-28485280

RESUMEN

AIMS: There is an increasing awareness of leaflet thrombosis following transcatheter aortic valve implantation (TAVI) and valve-in-valve (ViV) procedures. Nevertheless, the predisposing factors affecting transcatheter aortic valve (TAV) thrombosis have remained unclear. This study aimed to quantify the effects of reduced cardiac output (CO) on blood stasis on the TAV leaflets as a permissive factor for valve thrombosis. METHODS AND RESULTS: An idealised computational model representing a TAV was developed in a patient-specific geometry. Three-dimensional flow fields were obtained via a fluid-solid interaction modelling approach at different COs: 5.0, 3.5, 2.0 L/min. Blood residence time (BRT) was subsequently calculated on the leaflets. An association between reduced CO and increased blood stasis on the TAV leaflets was observed. At the end of diastole, larger areas of high BRT (>1.2 s) were observed at the leaflet's fixed edge at low COs. Such areas were calculated to be 2, 8, and 11% of the total surface area of leaflets at CO=5.0, 3.5, and 2.0 L/min, respectively, indicating a ~sixfold increase of BRT on the leaflets from the highest to the lowest CO. CONCLUSIONS: This study indicates an association between reduced CO and increased blood stasis on the TAV leaflets which can be regarded as a precursor of valve thrombosis.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Trombosis/patología , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Estenosis de la Válvula Aórtica/diagnóstico , Simulación por Computador , Femenino , Prótesis Valvulares Cardíacas/efectos adversos , Humanos , Estrés Mecánico , Trombosis/diagnóstico , Trombosis/terapia , Reemplazo de la Válvula Aórtica Transcatéter/métodos
19.
Eur J Cardiothorac Surg ; 51(5): 927-935, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28100471

RESUMEN

OBJECTIVES: Leaflet thrombosis following transcatheter aortic valve replacement (TAVR) and valve-in-valve (ViV) procedures has been increasingly recognized. However, the factors affecting the post-TAVR/ViV thrombosis are not fully understood. This study aimed to investigate the effect of the geometric confinement of transcatheter aortic valve (TAV) on blood residence time (BRT) on the TAV leaflets and in turn on the post-TAVR valve thrombosis. METHODS: Two computational models, representing a surgical bioprosthesis and a TAV, were developed to study the effect of the geometric confinement on BRT on the leaflets in ViV setting/TAVR Intra-annular positioning. 3D flow fields were obtained via a one-way fluid-solid interaction modelling approach validated by experimental testing. BRT was compared between the two models by quantification and statistical analysis of the residence time of randomly distributed particles in close proximity of the leaflets. RESULTS: Significantly longer BRT on the leaflets was observed in the TAV compared to the surgical valve during different stages of the cardiac cycle. During forward flow, the mean value of BRT was found to be 39% higher in the TAV compared to the surgical bioprosthesis ( P < 0.0001). During diastole, specifically from end-systole to mid-diastole and from mid-diastole to the beginning of systole, the amount by which the mean BRT was higher for TAV compared to the surgical valve was 150% and 40%, respectively ( P < 0.0005). CONCLUSIONS: The geometric confinement of TAV by the failed bioprosthesis or the calcified native valve increases the BRT on the TAV leaflets. This may act as a permissive factor in valve thrombosis.


Asunto(s)
Estenosis de la Válvula Aórtica/fisiopatología , Hemodinámica/fisiología , Modelos Cardiovasculares , Trombosis/fisiopatología , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Válvula Aórtica/fisiopatología , Válvula Aórtica/cirugía , Prótesis Valvulares Cardíacas/efectos adversos , Humanos
20.
Ann Thorac Surg ; 104(3): 751-759, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28483152

RESUMEN

BACKGROUND: Leaflet thrombosis after valve-in-valve (ViV) procedure has been increasingly recognized. This study aimed to investigate the flow dynamics aspect of leaflet thrombosis by quantifying the blood stasis on the noncoronary and coronary leaflets of a surgical aortic valve (SAV) and a transcatheter aortic valve (TAV) in a ViV setting. METHODS: Two computational models, representing a SAV and a TAV in ViV setting, were developed in a patient-specific geometry. Three-dimensional flow fields were obtained through a fluid-solid interaction modeling approach to study the difference in blood residence time (BRT) on the coronary and noncoronary leaflets. RESULTS: Longer BRT was observed on the TAV leaflets compared with the SAV, specifically near the leaflet fixed boundary. Particularly, at the end of diastole, the areas of high BRT (≥1.2 seconds) on the surface of the TAV model leaflets were four times larger than those of the SAV model. The distribution of BRT on the three leaflets exhibited a similar pattern in the model for the TAV in ViV setting. That was in contrast to the SAV model where large areas of high BRT were observed on the noncoronary leaflet. CONCLUSIONS: Geometric confinement of the TAV by the leaflets and the frame of the degenerated bioprosthesis that circumferentially surround the TAV stent increases the BRT on the leaflets, which may act as a permissive factor in the TAV leaflet thrombosis after ViV procedure. A similar distribution pattern of BRT observed on the TAV leaflets may explain the similar rate of occurrence of thrombosis on the three leaflets.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Bioprótesis/efectos adversos , Coagulación Sanguínea , Simulación por Computador , Prótesis Valvulares Cardíacas/efectos adversos , Modelos Cardiovasculares , Anciano , Estenosis de la Válvula Aórtica/sangre , Femenino , Humanos , Imagenología Tridimensional , Falla de Prótesis , Trombosis/cirugía
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