RESUMEN
Heart failure, broadly characterized by the gradual decline of the ability of the heart to maintain adequate blood flow throughout the body's vascular network of veins and arteries, is one of the leading causes of death worldwide. Mechanical Circulatory Support is one of the few available alternative interventions for late-stage heart failure with reduced ejection fraction. A ventricular assist device is surgically implanted and connected to the left and or right heart ventricles to provide additional bloodflow, off-loading the work required by the heart to maintain circulation. Modern mechanical circulatory support devices generate non-physiological flow conditions that can lead to the damage and rupture of blood cells (hemolysis), and the formation of blood clots (thrombosis), which pose severe health risks to the patient. It is essential to improve prediction tools for blood damage to reduce the risk of hemolysis and thrombosis. A simulation-based approach examines the interaction between hemolysis and thrombosis. Incompressible finite-volume computational fluid dynamics simulations are executed on an open-hub axial flow ventricular assist device. A continuum model of thrombosis and the intrinsic coagulation process is extended to include the effect of hemolysis. The model accounts for the effect of activation of platelets by shear stress, paracrine signaling, adhesion, and hemoglobin and ADP released during hemolysis. The effect of hemolysis with thrombosis is modelled by accounting for the hyper-adhesivity of von-Willebrand Factor on extracellular hemoglobin, and the increased rate of platelet activation induced by ADP release. Thrombosis is assessed at varying inflow rates and rotor speeds, and cases are executed where thrombosis is affected by ADP release and Hb-induced hyper-adhesivity. It is found that there is a non-negligible effect from hemolysis on thrombosis across a range of rotor speeds, and that hyperadhesivity plays a dominant role in thrombus formation in the presence of hemolysis.
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Corazón Auxiliar , Hemólisis , Trombosis , Trombosis/fisiopatología , Corazón Auxiliar/efectos adversos , Humanos , Hidrodinámica , Modelos Biológicos , Simulación por ComputadorRESUMEN
Sepsis and atherosclerotic cardiovascular disease (ASCVD) are major health challenges involving complex processes like inflammation, renin-angiotensin system (RAS) dysregulation, and thrombosis. Despite distinct clinical symptoms, both conditions share mechanisms mediated by bradykinin. This review explores bradykinin's role in inflammation, RAS modulation, and thrombosis in sepsis and ASCVD. In sepsis, variable kininogen-bradykinin levels may correlate with disease severity and progression, though the effect of bradykinin receptor modulation on inflammation remains uncertain. RAS activation is present in both diseases, with sepsis showing variable or low levels of Ang II, ACE, and ACE2, while ASCVD consistently exhibits elevated levels. Bradykinin may act as a mediator for ACE2 and AT2 receptor effects in RAS regulation. It may influence clotting and fibrinolysis in sepsis-associated coagulopathy, but evidence for an antithrombotic effect in ASCVD is insufficient. Understanding bradykinin's role in these shared pathologies could guide therapeutic and monitoring strategies and inform future research.
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Aterosclerosis , Coagulación Sanguínea , Bradiquinina , Sistema Renina-Angiotensina , Sepsis , Transducción de Señal , Humanos , Bradiquinina/metabolismo , Sepsis/fisiopatología , Sepsis/metabolismo , Sepsis/sangre , Aterosclerosis/fisiopatología , Aterosclerosis/metabolismo , Aterosclerosis/sangre , Animales , Coagulación Sanguínea/efectos de los fármacos , Receptores de Bradiquinina/metabolismo , Trombosis/fisiopatología , Trombosis/sangre , Trombosis/metabolismoRESUMEN
BACKGROUND: Left atrial appendage (LAA) slow-flow may increase the risk of ischemic stroke. We studied LAA attenuation on cardiac computed tomography in patients with acute ischemic stroke. METHODS AND RESULTS: We used data from a prospective cohort of patients with acute ischemic stroke undergoing cardiac computed tomography during the acute stroke imaging protocol. We compared characteristics, functional outcome (modified Rankin scale: higher scores indicating worse outcome), stroke recurrence and major adverse cardiovascular events after 2-year follow-up between patients with LAA thrombus (filling defect<100 Hounsfield Unit (HU)), slow-flow (filling defect ≥100 HU) and normal filling. Of 421 patients, 31 (7%) had LAA thrombus, 69 (16%) slow-flow, and 321 (76%) normal filling. Patients with thrombus or slow-flow more often had known atrial fibrillation compared with normal filling (45%, 39%, and 9%, P<0.001). Patients with thrombus had higher National Institutes of Health Stroke Scale-scores compared with slow-flow and normal filling (18 [interquartile range, 9-22], 6 [interquartile range, 3-17], and 5 [interquartile range, 2-11], P<0.001). Compared with normal filling, there was no difference with slow-flow in functional outcome (median modified Rankin scale, 3 versus 2; acOR 0.8 [95% CI, 0.5-1.4]), stroke recurrence (adjusted hazard ratio, 0.8 [95% CI, 0.3-1.9]) or major adverse cardiovascular events (adjusted hazard ratio, 1.2 [95% CI, 0.7-2.1]), while patients with thrombus had worse functional outcome (median modified Rankin scale, 6, acOR, 3.3 [95% CI, 1.5-7.4]). In cryptogenic stroke patients (n=156) slow-flow was associated with stroke recurrence (27% versus 6%, aHR, 4.1 [95% CI, 1.1-15.7]). CONCLUSIONS: Patients with slow-flow had similar characteristics to patients with thrombus, but had less severe strokes. Slow-flow was not significantly associated with functional outcome or major adverse cardiovascular events, but was associated with recurrent stroke in patients with cryptogenic stroke.
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Apéndice Atrial , Accidente Cerebrovascular Isquémico , Humanos , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/fisiopatología , Masculino , Femenino , Anciano , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/fisiopatología , Accidente Cerebrovascular Isquémico/etiología , Persona de Mediana Edad , Estudios Prospectivos , Recurrencia , Anciano de 80 o más Años , Factores de Riesgo , Trombosis/diagnóstico por imagen , Trombosis/etiología , Trombosis/fisiopatología , Tomografía Computarizada por Rayos X , Fibrilación Atrial/complicaciones , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/diagnóstico por imagen , Factores de Tiempo , Valor Predictivo de las PruebasRESUMEN
A 6-year-old boy had previously undergone total anomalous pulmonary venous connection repair and postoperative pulmonary vein stenosis release. Magnetic resonance imaging revealed blood stasis caused by a collision between the inflow from the pulmonary veins and the outflow from the left atrial appendage. A surgical specimen revealed evidence of advanced thrombus attachment. Infra-cardiac total anomalous pulmonary venous connection with an antler appearance may be a risk factor for thrombus formation in the left atrial appendage and for postoperative pulmonary venous stenosis due to blood flow collision in the left atrium after total anomalous pulmonary venous connection repair.
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Venas Pulmonares , Trombosis , Humanos , Masculino , Niño , Trombosis/diagnóstico por imagen , Trombosis/etiología , Trombosis/cirugía , Trombosis/fisiopatología , Resultado del Tratamiento , Venas Pulmonares/anomalías , Venas Pulmonares/cirugía , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/fisiopatología , Síndrome de Cimitarra/cirugía , Síndrome de Cimitarra/diagnóstico por imagen , Síndrome de Cimitarra/fisiopatología , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Imagen por Resonancia Magnética , Cardiopatías/diagnóstico por imagen , Cardiopatías/cirugía , Cardiopatías/etiología , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/cirugía , Atrios Cardíacos/anomalías , Estenosis de Vena Pulmonar/diagnóstico por imagen , Estenosis de Vena Pulmonar/etiología , Estenosis de Vena Pulmonar/cirugía , Estenosis de Vena Pulmonar/fisiopatología , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/anomalías , Apéndice Atrial/cirugía , Apéndice Atrial/fisiopatologíaRESUMEN
The association between sepsis and thrombotic complications is still not well known. Different mechanisms have been shown to be involved in the sepsis-induced prothrombotic state, but clinical scenarios may differ. In this review, we have summarized the role that bacterial products such as porins and toxins can have in the induction of the prothrombotic state during sepsis and the interaction that they can have with each other. Furthermore, the above-mentioned mechanisms might be involved in the pattern of the clinical presentation of thrombotic events during bacterial sepsis, which would secondarily explain the association between sepsis and venous thromboembolism, the association between sepsis and disseminated intravascular coagulation, and the association between sepsis and microangiopathic venous thromboembolism.
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Sepsis , Trombosis , Humanos , Sepsis/microbiología , Sepsis/complicaciones , Sepsis/fisiopatología , Trombosis/fisiopatología , Trombosis/etiología , Animales , Coagulación Sanguínea , Coagulación Intravascular Diseminada/fisiopatología , Coagulación Intravascular Diseminada/etiología , Coagulación Intravascular Diseminada/microbiología , Toxinas Bacterianas/toxicidad , Tromboembolia Venosa/etiología , Tromboembolia Venosa/fisiopatologíaRESUMEN
Cardiac compartmental size depends on sex, with smaller values found in (healthy) women compared to a matched group of men. Various types of heart disease may cause dilation of the affected chamber. For example, atrial fibrillation (AF) is associated with enlarged left atrial (LA) size, often also implying increased left ventricular (LV) size. Sex-specific differences appear to persist during disease states. Thus, chamber volumes depend on both sex and the severity of the underlying disorder, and require quantification to evaluate the effect of interventions. Often, we rely on the popular performance metric ejection fraction (EF) which refers to the ratio of the minimum and maximum LV or LA volumetric values observed during the cardiac cycle. Here we discuss a sex stratified analysis of LVEF and LAEF in AF patients as treated by LA appendage closure, while comparing those with or without device-related thrombosis. Also, an alternative analysis based on primary data is presented while emphasizing its attractiveness. In any event, age- and sex-specific reference values as broadly documented for various imaging modalities should be applied to LA and LV.
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Fibrilación Atrial , Volumen Sistólico , Trombosis , Humanos , Volumen Sistólico/fisiología , Femenino , Masculino , Trombosis/fisiopatología , Trombosis/etiología , Fibrilación Atrial/fisiopatología , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/fisiopatologíaRESUMEN
Transcatheter aortic heart valve thrombosis (THVT) affects long-term valve durability, transvalvular pressure gradient and leaflet mobility. In this study, we conduct high-fidelity fluid-structure interaction simulations to perform Lagrangian particle tracing in a generic model with larger aortic diameters (THVT model) with and without neo-sinus which is compared to a model of unaffected TAVI patients (control model). Platelet activation indices are computed for each particle to assess the risk of thrombus formation induced by high shear stresses followed by flow stagnation. Particle tracing indicates that fewer particles contribute to sinus washout of the THVT model with and without neo-sinus compared to the control model (-34.9%/-34.1%). Stagnating particles in the native sinus of the THVT model show higher platelet activation indices than for the control model (+39.6% without neo-sinus, +45.3% with neo-sinus). Highest activation indices are present for particles stagnating in the neo-sinus of the larger aorta representing THVT patients (+80.2% compared to control). This fluid-structure interaction (FSI) study suggests that larger aortas lead to less efficient sinus washout in combination with higher risk of platelet activation among stagnating particles, especially within the neo-sinus. This could explain (a) a higher occurrence of thrombus formation in transcatheter valves compared to surgical valves without neo-sinus and (b) the neo-sinus as the prevalent region for thrombi in TAV. Pre-procedural identification of larger aortic roots could contribute to better risk assessment of patients and improved selection of a patient-specific anti-coagulation therapy.
Asunto(s)
Válvula Aórtica , Modelos Cardiovasculares , Activación Plaquetaria , Trombosis , Humanos , Trombosis/fisiopatología , Trombosis/patología , Activación Plaquetaria/fisiología , Válvula Aórtica/patología , Válvula Aórtica/cirugía , Reemplazo de la Válvula Aórtica Transcatéter , Aorta/fisiopatologíaRESUMEN
BACKGROUND: Post implantation syndrome (PIS) is a well-defined entity with unclear etiology, complicating a number of patients with abdominal aortic aneurysms treated with endovascular aortic repair (EVAR). The aim of this study was to assess the platelets' role and the influence of aneurysmal sac thrombus volumes in the development of PIS. A retrospective analysis of prospectively collected data was performed, and 76 patients who were treated by EVAR (2011-2013) were studied. Aneurysms with endoleak were not included in the study. Based on the criteria for systemic inflammatory response syndrome (SIRS), 17 patients (22%) developed PIS (which is considered a SIRS analogue), while 59 (78%) did not. METHODS: The 2 groups were compared in relation to the following parameters: baseline platelet count (PLT), decrease of platelet count (PLT drop), volume of the arterial flow before the procedure (V flow), volume of thrombus of the aneurysm (V thromb), ratio of thrombus volume to aneurysm sac volume (V ratio), and the volume of newly formed thrombus (V new). Volume flow measurements were calculated by Osirix software preoperatively and in the first month postoperatively. Parametric and nonparametric techniques (unpaired t-test, Mann-Whitney U test) were used accordingly. RESULTS: Baseline platelets absolute count was greater in the PIS group (239,000 ± 17,000) versus the non-PIS group (194,000 ± 6,900, P = 0.004), and the PLT drop was larger in the PIS group (74,000 ± 15,600 versus 45,000 ± 5,300, P = 0.019). No difference was found regarding the aneurysm volumes (V flow, V thromb, V ratio, and V new) between the 2 groups. CONCLUSIONS: Platelets, in terms of their absolute baseline count and their decrease after the procedure, seem to be an important factor in developing PIS after EVAR. Further, more tailored studies are needed to elucidate the role of platelets and flow or thrombus volumes in the development of PIS.
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Aneurisma de la Aorta Abdominal , Plaquetas , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Trombosis , Humanos , Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/sangre , Estudios Retrospectivos , Procedimientos Endovasculares/efectos adversos , Trombosis/etiología , Trombosis/diagnóstico por imagen , Trombosis/sangre , Trombosis/fisiopatología , Implantación de Prótesis Vascular/efectos adversos , Resultado del Tratamiento , Masculino , Recuento de Plaquetas , Femenino , Anciano , Factores de Tiempo , Anciano de 80 o más Años , Factores de Riesgo , Aortografía , Síndrome , Síndrome de Respuesta Inflamatoria Sistémica/etiología , Síndrome de Respuesta Inflamatoria Sistémica/sangre , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Flujo Sanguíneo RegionalRESUMEN
BACKGROUND: Myocardial strain can analyze early myocardial dysfunction after myocardial infarction (MI). However, the correlation between left ventricular (LV) strain (including regional and global strain) obtained by cardiac magnetic resonance (CMR) imaging and left ventricular thrombus (LVT) after ST-segment elevation myocardial infarction (STEMI) is unclear. METHODS: The retrospective clinical observation study included patients with LVT (n = 20) and non-LVT (n = 195) who underwent CMR within two weeks after STEMI. CMR images were analyzed using CVI 42 (Circle Cardiovascular Imaging, Canada) to obtain LV strain values. Logistic regression analysis identified risk factors for LVT among baseline characteristics, CMR ventricular strain, and left ventricular ejection fraction (LVEF). Considering potential correlations between strains, the ability of LV strain to identify LVT was evaluated using 9 distinct models. Receiver operating characteristic curves were generated with GraphPad Prism, and the area under the curve (AUC) of LVEF, apical longitudinal strain (LS), and circumferential strain (CS) was calculated to determine their capacity to distinguish LVT. RESULTS: Among 215 patients, 9.3% developed LVT, with a 14.5% incidence in those with anterior MI. Univariate regression indicated associations of LAD infarct-related artery, lower NT-proBNP, lower LVEF, and reduced global, midventricular, and apical strain with LVT. Further multivariable regression analysis showed that apical LS, LVEF and NT-proBNP were still independently related to LVT (Apical LS: OR = 1.14, 95%CI (1.01, 1.30), P = 0.042; LVEF: OR = 0.91, 95%CI (0.85, 0.97), P = 0.005; NT-proBNP: OR = 2.35, 95%CI (1.04, 5.31) ). CONCLUSION: Reduced apical LS on CMR is independently associated with LVT after STEMI.
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Imagen por Resonancia Cinemagnética , Valor Predictivo de las Pruebas , Infarto del Miocardio con Elevación del ST , Volumen Sistólico , Función Ventricular Izquierda , Humanos , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/fisiopatología , Infarto del Miocardio con Elevación del ST/complicaciones , Infarto del Miocardio con Elevación del ST/terapia , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Factores de Riesgo , Contracción Miocárdica , Fragmentos de Péptidos/sangre , Análisis Multivariante , Fenómenos Biomecánicos , Péptido Natriurético Encefálico/sangre , Curva ROC , Trombosis/diagnóstico por imagen , Trombosis/fisiopatología , Trombosis/etiología , Factores de Tiempo , Infarto de la Pared Anterior del Miocardio/diagnóstico por imagen , Infarto de la Pared Anterior del Miocardio/fisiopatología , Infarto de la Pared Anterior del Miocardio/complicaciones , Infarto de la Pared Anterior del Miocardio/terapia , Oportunidad Relativa , Distribución de Chi-Cuadrado , Cardiopatías/diagnóstico por imagen , Cardiopatías/fisiopatología , Cardiopatías/etiologíaAsunto(s)
Prótesis Valvulares Cardíacas , Trombosis , Humanos , Trombosis/diagnóstico por imagen , Trombosis/etiología , Trombosis/fisiopatología , Resultado del Tratamiento , Falla de Prótesis , Válvula Pulmonar/diagnóstico por imagen , Válvula Pulmonar/cirugía , Válvula Pulmonar/fisiopatología , Diseño de Prótesis , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Masculino , Inflamación/fisiopatología , FemeninoRESUMEN
ABSTRACT: Collateral circulation is often secondary to a regional thrombosis. This phenomenon can lead to the detection of misleading bone lesions on imaging and is a well-known source of false-positives. Here, we present 2 different tracers PET/CT images, 18 F-FDG and 18 F-choline, with collateral circulation but without obvious thrombosis. Both cases displayed bone uptake, which mimicked metastasis. However, clinical follow-up ruled out metastasis and revealed false-positive bone lesions related to collateral circulation, even in the lack of acute or chronic underlying thrombotic processes.
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Circulación Colateral , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Trombosis , Humanos , Trombosis/diagnóstico por imagen , Trombosis/fisiopatología , Reacciones Falso Positivas , Masculino , Trazadores Radiactivos , Persona de Mediana Edad , Femenino , Colina/análogos & derivados , Huesos/diagnóstico por imagenRESUMEN
This case report documents the management of a 66-year old man with atrial fibrillation with recent placement of a WATCHMAN® Flex atrial appendage occlusion device. The patient presented with renal failure, abdominal pain, and difficulty walking 2 months after placement. The WATCHMAN® Flex device was found to have embolized to his abdominal aorta at the level of the renal arteries with associated thrombus. Extensive workup revealed reduced left ventricular cardiac function and decreased renal function, both of which were felt to be potentially reversible with device removal. The patient then underwent retrieval of the device and all associated thrombus via an open retroperitoneal approach. This case demonstrates a potential consequence of implanting devices such as an atrial appendage occlusion device and describes a technique for removal.
Asunto(s)
Apéndice Atrial , Fibrilación Atrial , Remoción de Dispositivos , Migración de Cuerpo Extraño , Humanos , Anciano , Masculino , Apéndice Atrial/fisiopatología , Apéndice Atrial/diagnóstico por imagen , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/terapia , Fibrilación Atrial/diagnóstico , Resultado del Tratamiento , Migración de Cuerpo Extraño/etiología , Migración de Cuerpo Extraño/diagnóstico por imagen , Migración de Cuerpo Extraño/terapia , Aorta Abdominal/diagnóstico por imagen , Aorta Abdominal/cirugía , Diseño de Prótesis , Cateterismo Cardíaco/instrumentación , Cateterismo Cardíaco/efectos adversos , Trombosis/etiología , Trombosis/diagnóstico por imagen , Trombosis/terapia , Trombosis/fisiopatología , Aortografía , Angiografía por Tomografía Computarizada , Embolia/etiología , Embolia/diagnóstico por imagen , Embolia/terapiaRESUMEN
OBJECTIVE: To evaluate left atrial volume and function in patients with paroxysmal atrial fibrillation (AF) combined with left atrial appendage thrombosis and patients with paroxysmal AF without left atrial appendage thrombosis by 3-dimensional speckle tracking imaging (3D-STI), and to explore the application value of this set of parameters in the evaluation of left atrial function in patients with paroxysmal AF. MATERIALS AND METHODS: A total of 40 patients with paroxysmal AF admitted from December 2018 to December 2020 were selected as the observation group. All patients with paroxysmal AF in the observation group underwent transesophageal echocardiography. According to the presence of left atrial appendage thrombosis, the patients were divided into the AF without thrombosis group (24 cases) and the AF with thrombosis group (16 cases). Thirty normal people were selected as control group who were chosen as having no heart-related disease. The left atrial volume parameters (Left atrial maximum volume LAVmax, Left atrial minimum volume LAVmin, Left atrial volume before atrial contraction LAVpre-A, Left atrial stroke volume LAEV), left atrial ejection fraction (LAEF) and left atrial strain parameters (Left atrial reservoir longitudinal strain LASr, Left atrial conduit longitudinal strain LAScd, Left atrial contraction longitudinal strain LASct, Left atrial reservoir circumferential strain LASr-c, Left atrial conduit circumferential strain LAScd-c, Left atrial contraction circumferential strain LASct-c) of the 3 groups were measured by 3D-STI. RESULTS: With the progression of paroxysmal AF, the left atrial volume increased, and the reservoir, conduit and contractile function were damaged. The left atrial volume continued to increase, and the reservoir, conduit and contractile function further decreased significantly in patients with AF combined with left atrial appendage thrombosis. LAEF was positively correlated with LASr and LASr_c. CONCLUSION: Real-time 3-dimensional spot tracking imaging (3D-STI) can evaluate the changes in left atrial volume and function in patients with paroxysmal AF, and has a certain reference value for clinical judgment of disease progression and prognosis.
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Apéndice Atrial , Fibrilación Atrial , Función del Atrio Izquierdo , Humanos , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/diagnóstico por imagen , Masculino , Femenino , Persona de Mediana Edad , Función del Atrio Izquierdo/fisiología , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/fisiopatología , Ecocardiografía Tridimensional/métodos , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Ecocardiografía Transesofágica/métodos , Anciano , Trombosis/diagnóstico por imagen , Trombosis/etiología , Trombosis/fisiopatologíaRESUMEN
Carotid artery webs (CaW) are non-atherosclerotic projections into the vascular lumen and have been linked to up to one-third of cryptogenic strokes in younger patients. Determining how CaW affects local hemodynamics is essential for understanding clot formation and stroke risk. Computational fluid dynamics simulations were used to investigate patient-specific hemodynamics in carotid artery bifurcations with CaW, bifurcations with atherosclerotic lesions having a similar degree of lumen narrowing, and with healthy carotid bifurcations. Simulations were conducted using segmented computed tomography angiography geometries with inlet boundary conditions extracted from 2D phase contrast MRI scans. The study included carotid bifurcations with CaW (n = 13), mild atherosclerosis (n = 7), and healthy bifurcation geometries (n = 6). Hemodynamic parameters associated with vascular dysfunction and clot formation, including shear rate, oscillatory shear index (OSI), low velocity, and flow stasis were calculated and compared between the subject groups. Patients with CaW had significantly larger regions containing low shear rate, high OSI, low velocity, and flow stasis in comparison to subjects with mild atherosclerosis or normal bifurcations. These abnormal hemodynamic metrics in patients with CaW are associated with clot formation and vascular dysfunction and suggest that hemodynamic assessment may be a tool to assess stroke risk in these patients.
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Enfermedades de las Arterias Carótidas , Hemodinámica , Humanos , Masculino , Enfermedades de las Arterias Carótidas/fisiopatología , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Femenino , Persona de Mediana Edad , Anciano , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/fisiopatología , Angiografía por Tomografía Computarizada , Trombosis/fisiopatología , Trombosis/diagnóstico por imagen , Imagen por Resonancia MagnéticaRESUMEN
BACKGROUND: This study investigates the hypothesis that presence of atrial fibrillation (AF) in LVAD patients increases thrombogenicity in the left ventricle (LV) and exacerbates stroke risk. METHODS: Using an anatomical LV model implanted with an LVAD inflow cannula, we analyze thrombogenic risk and blood flow patterns in either AF or sinus rhythm (SR) using unsteady computational fluid dynamics (CFD). To analyze platelet activation and thrombogenesis in the LV, hundreds of thousands of platelets are individually tracked to quantify platelet residence time (RT) and shear stress accumulation history (SH). RESULTS: The irregular and chaotic mitral inflow associated with AF results in markedly different intraventricular flow patterns, with profoundly negative impact on blood flow-induced stimuli experienced by platelets as they traverse the LV. Twice as many platelets accumulated very high SH in the LVAD + AF case, resulting in a 36% increase in thrombogenic potential score, relative to the LVAD + SR case. CONCLUSIONS: This supports the hypothesis that AF results in unfavorable blood flow patterns in the LV adding to an increased stroke risk for LVAD + AF patients. Quantification of thrombogenic risk associated with AF for LVAD patients may help guide clinical decision-making on interventions to mitigate the increased risk of thromboembolic events.
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Fibrilación Atrial , Corazón Auxiliar , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/etiología , Corazón Auxiliar/efectos adversos , Humanos , Trombosis/etiología , Trombosis/fisiopatología , Activación Plaquetaria , Modelos Cardiovasculares , Ventrículos Cardíacos/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Plaquetas/metabolismo , Función Ventricular Izquierda , Modelos Anatómicos , Hidrodinámica , HemodinámicaRESUMEN
PURPOSE OF REVIEW: Dysfunction and thrombosis of mechanical heart valves, although uncommon, represents a challenge that requires multidisciplinary expertise for diagnosis and management. The aim of this review is to summarize strengths and weaknesses of diagnostic methods and therapeutic strategies for this uncommon but potentially life-threatening pathology. RECENT FINDINGS: Expeditious diagnosis of mechanical valve thrombosis and exclusion of other diagnostic considerations, often with incorporation of multimodality imaging, can inform the best treatment strategy. Presentation of mechanical valve thrombosis can be asymptomatic or can include heart failure, life-threatening embolic events, or cardiogenic shock. Echocardiography, fluoroscopy and computed tomography are important in the evaluation of mechanical valve dysfunction. Therapeutic strategies for thrombosis include anticoagulation, systemic thrombolysis, and surgery. Choice of treatment depends on multiple factors including thrombus size, degree of valve dysfunction, clinical presentation, and available surgical expertise.
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Prótesis Valvulares Cardíacas , Trombosis , Humanos , Trombosis/etiología , Trombosis/diagnóstico por imagen , Trombosis/terapia , Trombosis/fisiopatología , Terapia Trombolítica/métodos , Anticoagulantes/uso terapéutico , Ecocardiografía , Enfermedades de las Válvulas Cardíacas/terapia , Enfermedades de las Válvulas Cardíacas/fisiopatología , Falla de Prótesis , Tomografía Computarizada por Rayos XRESUMEN
AIMS: Blood stasis is crucial in developing left atrial (LA) thrombi. LA appendage peak flow velocity (LAAFV) is a quantitative parameter for estimating thromboembolic risk. However, its impact on LA thrombus resolution and clinical outcomes remains unclear. METHODS AND RESULTS: The LAT study was a multicentre observational study investigating patients with atrial fibrillation (AF) and silent LA thrombi detected by transoesophageal echocardiography (TEE). Among 17 436 TEE procedures for patients with AF, 297 patients (1.7%) had silent LA thrombi. Excluding patients without follow-up examinations, we enrolled 169 whose baseline LAAFV was available. Oral anticoagulation use increased from 85.7% at baseline to 97.0% at the final follow-up (P < 0.001). During 1 year, LA thrombus resolution was confirmed in 130 (76.9%) patients within 76 (34-138) days. Conversely, 26 had residual LA thrombi, 8 had thromboembolisms, and 5 required surgical removal. These patients with failed thrombus resolution had lower baseline LAAFV than those with successful resolution (18.0 [15.8-22.0] vs. 22.2 [17.0-35.0], P = 0.003). Despite limited predictive power (area under the curve, 0.659; P = 0.001), LAAFV ≤ 20.0â cm/s (best cut-off) significantly predicted failed LA thrombus resolution, even after adjusting for potential confounders (odds ratio, 2.72; 95% confidence interval, 1.22-6.09; P = 0.015). The incidence of adverse outcomes including ischaemic stroke/systemic embolism, major bleeding, or all-cause death was significantly higher in patients with reduced LAAFV than in those with preserved LAAFV (28.4% vs. 11.6%, log-rank P = 0.005). CONCLUSION: Failed LA thrombus resolution was not rare in patients with AF and silent LA thrombi. Reduced LAAFV was associated with failed LA thrombus resolution and adverse clinical outcomes.
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Anticoagulantes , Apéndice Atrial , Fibrilación Atrial , Ecocardiografía Transesofágica , Trombosis , Humanos , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/complicaciones , Masculino , Femenino , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/fisiopatología , Anciano , Trombosis/fisiopatología , Trombosis/diagnóstico por imagen , Trombosis/complicaciones , Persona de Mediana Edad , Velocidad del Flujo Sanguíneo , Anticoagulantes/uso terapéutico , Factores de Riesgo , Resultado del Tratamiento , Enfermedades Asintomáticas , Factores de Tiempo , Cardiopatías/fisiopatología , Cardiopatías/complicaciones , Cardiopatías/diagnóstico por imagen , Tromboembolia/etiología , Tromboembolia/fisiopatología , Anciano de 80 o más Años , Función del Atrio IzquierdoRESUMEN
BACKGROUND: Thromboinflammation is caused by mutual activation of platelets and neutrophils. The site of thromboinflammation is determined by chemoattracting agents release by endothelium, immune cells, and platelets. Impaired neutrophil chemotaxis contributes to the pathogenesis of Shwachman-Diamond syndrome (SDS). In this hereditary disorder, neutrophils are known to have aberrant chemoattractant-induced F-actin properties. Here, we aim to determine whether neutrophil chemotaxis could be analyzed using our previously developed ex vivo assay of the neutrophils crawling among the growing thrombi. METHODS: Adult and pediatric healthy donors, alongside with pediatric patients with SDS, were recruited for the study. Thrombus formation and granulocyte movement in hirudinated whole blood were visualized by fluorescent microscopy in fibrillar collagen-coated parallel-plate flow chambers. Alternatively, fibrinogen, fibronectin, vWF, or single tumor cells immobilized on coverslips were used. A computational model of chemokine distribution in flow chamber with a virtual neutrophil moving in it was used to analyze the observed data. RESULTS: The movement of healthy donor neutrophils predominantly occurred in the direction and vicinity of thrombi grown on collagen or around tumor cells. For SDS patients or on coatings other than collagen, the movement was characterized by randomness and significantly reduced velocities. Increase in wall shear rates to 300-500 1/s led to an increase in the proportion of rolling neutrophils. A stochastic algorithm simulating leucocyte chemotaxis movement in the calculated chemoattractant field could reproduce the experimental trajectories of moving neutrophils for 72% of cells. CONCLUSIONS: In samples from healthy donors, but not SDS patients, neutrophils move in the direction of large, chemoattractant-releasing platelet thrombi growing on collagen.
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Neutrófilos , Trombosis , Humanos , Neutrófilos/fisiología , Trombosis/fisiopatología , Quimiotaxis , Adulto , Niño , Masculino , Quimiotaxis de Leucocito , Femenino , Movimiento CelularRESUMEN
Clinical failure of arteriovenous neointimal hyperplasia (NIH) fistulae (AVF) is frequently due to juxta-anastomotic NIH (JANIH). Although the mouse AVF model recapitulates human AVF maturation, previous studies focused on the outflow vein distal to the anastomosis. We hypothesized that the juxta-anastomotic area (JAA) has increased NIH compared with the outflow vein. AVF was created in C57BL/6 mice without or with chronic kidney disease (CKD). Temporal and spatial changes of the JAA were examined using histology and immunofluorescence. Computational techniques were used to model the AVF. RNA-seq and bioinformatic analyses were performed to compare the JAA with the outflow vein. The jugular vein to carotid artery AVF model was created in Wistar rats. The neointima in the JAA shows increased volume compared with the outflow vein. Computational modeling shows an increased volume of disturbed flow at the JAA compared with the outflow vein. Endothelial cells are immediately lost from the wall contralateral to the fistula exit, followed by thrombus formation and JANIH. Gene Ontology (GO) enrichment analysis of the 1,862 differentially expressed genes (DEG) between the JANIH and the outflow vein identified 525 overexpressed genes. The rat jugular vein to carotid artery AVF showed changes similar to the mouse AVF. Disturbed flow through the JAA correlates with rapid endothelial cell loss, thrombus formation, and JANIH; late endothelialization of the JAA channel correlates with late AVF patency. Early thrombus formation in the JAA may influence the later development of JANIH.NEW & NOTEWORTHY Disturbed flow and focal endothelial cell loss in the juxta-anastomotic area of the mouse AVF colocalizes with acute thrombus formation followed by late neointimal hyperplasia. Differential flow patterns between the juxta-anastomotic area and the outflow vein correlate with differential expression of genes regulating coagulation, proliferation, collagen metabolism, and the immune response. The rat jugular vein to carotid artery AVF model shows changes similar to the mouse AVF model.
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Derivación Arteriovenosa Quirúrgica , Hiperplasia , Venas Yugulares , Ratones Endogámicos C57BL , Neointima , Ratas Wistar , Trombosis , Animales , Trombosis/fisiopatología , Trombosis/patología , Trombosis/genética , Trombosis/etiología , Trombosis/metabolismo , Masculino , Venas Yugulares/metabolismo , Venas Yugulares/patología , Venas Yugulares/fisiopatología , Modelos Animales de Enfermedad , Arterias Carótidas/patología , Arterias Carótidas/fisiopatología , Arterias Carótidas/metabolismo , Arterias Carótidas/cirugía , Ratones , Ratas , Flujo Sanguíneo Regional , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Endotelio Vascular/patología , Insuficiencia Renal Crónica/patología , Insuficiencia Renal Crónica/fisiopatología , Insuficiencia Renal Crónica/genética , Insuficiencia Renal Crónica/metabolismo , Células Endoteliales/metabolismo , Células Endoteliales/patologíaRESUMEN
Despite the prognostic effect of physical activity, acute bouts of high-volume endurance exercise can induce cardiac stress and postexercise hypercoagulation associated with increased thrombotic risk. The aim of this study was to explore the effect of high-volume endurance exercise on coagulation and thrombotic activity in recreational cyclists. Thirty-four recreational cyclists completed 4.8 ± 0.3 h of cycling at 45 ± 5% of maximal power output on a bicycle ergometer. Intravenous blood samples were collected preexercise, immediately postexercise, 24 and 48 h postexercise, and analyzed for brain natriuretic peptide (BNP), cardiac troponin (cTn), C-reactive protein (CRP), D-dimer, thrombin-antithrombin (TAT) complex, tissue factor (TF), tissue factor pathway inhibitor (TFPI), and TF-to-TFPI ratio (TF:TFPI). An increase in cTn was observed postexercise (P < 0.001). CRP concentrations were increased at 24 and 48 h postexercise compared with preexercise concentrations (P ≤ 0.001). TF was elevated at 24 h postexercise (P < 0.031) and TFPI was higher immediately postexercise (P < 0.044) compared with all other time points. TF:TFPI was increased at 24 and 48 h postexercise compared with preexercise (P < 0.025). TAT complex was reduced at 48 h postexercise compared with preexercise (P = 0.015), D-dimer was higher immediately postexercise compared with all other time points (P ≤ 0.013). No significant differences were observed in BNP (P > 0.05). High-volume endurance cycling induced markers of cardiac stress among recreational cyclists. However, plasma coagulation and fibrinolytic activity suggest no increase in thrombotic risk after high-volume endurance exercise.NEW & NOTEWORTHY In this study, a high-volume endurance exercise protocol induced markers of cardiac stress and altered plasma coagulation and fibrinolytic activity for up to 48 h in recreationally active cyclists. However, analysis of coagulation biomarkers indicates no increase in thrombotic risk when appropriate hydration and rest protocols are implemented.