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1.
Ann Oncol ; 23(8): 1998-2005, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22473596

RESUMEN

BACKGROUND: Patients with active cancer are often on chronic anticoagulation and frequently require interruption of this treatment for invasive procedures. The impact of cancer on periprocedural thromboembolism (TE) and major bleeding is not known. PATIENTS AND METHODS: Two thousand one hundred and eighty-two consecutive patients referred for periprocedural anticoagulation (2484 procedures) using a standardized protocol were followed forward in time to estimate the 3-month incidence of TE, major bleeding and survival stratified by anticoagulation indication. For each indication, we tested active cancer and bridging heparin therapy as potential predictors of TE and major bleeding. RESULTS: Compared with patients without cancer, active cancer patients (n=493) had more venous thromboembolism (VTE) complications (1.2% versus 0.2%; P=0.001), major bleeding (3.4% versus 1.7%; P=0.02) and reduced survival (95% versus 99%; P<0.001). Among active cancer patients, only those chronically anticoagulated for VTE had higher rates of periprocedural VTE (2% versus 0.16%; P=0.002) and major bleeding (3.7% versus 0.6%; P<0.001). Bridging with heparin increased the rate of major bleeding in cancer patients (5% versus 1%; P=0.03) without impacting the VTE rate (0.7% versus 1.4%, P=0.50). CONCLUSIONS: Cancer patients anticoagulated for VTE experience higher rates of periprocedural VTE and major bleeding. Periprocedural anticoagulation for these patients requires particular attention to reduce these complications.


Asunto(s)
Anticoagulantes/administración & dosificación , Hemorragia/etiología , Neoplasias/sangre , Tromboembolia Venosa/etiología , Anciano , Anticoagulantes/efectos adversos , Femenino , Hemorragia/sangre , Hemorragia/inducido químicamente , Heparina de Bajo-Peso-Molecular/administración & dosificación , Heparina de Bajo-Peso-Molecular/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tromboembolia Venosa/sangre , Tromboembolia Venosa/inducido químicamente , Warfarina/administración & dosificación , Warfarina/efectos adversos
2.
J Thromb Haemost ; 16(7): 1278-1287, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29753308

RESUMEN

Essentials Net benefit of venous thromboprophylaxis (VTE) in patients hospitalized for infections is unknown. MAGELLAN trial subgroup analysis was performed for patients hospitalized for acute infectious diseases. At day 35, prolonged rivaroxaban prophylaxis reduced VTE compared to enoxaparin (4.2% vs. 6.6%). Rivaroxaban prophylaxis reduced VTE in patients hospitalized for active lung infections. SUMMARY: Background Despite the well-established association between infection and venous thromboembolism (VTE), there are few data specifically assessing the efficacy and safety of the VTE prophylaxis strategies for patients hospitalized for acute infectious diseases. Objectives To estimate the incidence of VTE and bleeding outcomes, comparing prolonged prophylaxis with rivaroxaban 10 mg daily for 35 days with enoxaparin 40 mg daily for 10 days. Patients/Methods A subgroup analysis of patients hospitalized for acute infectious diseases in the MAGELLAN trial was performed. The primary efficacy outcome was the composite of asymptomatic proximal or symptomatic VTE at days 10 and 35. The principal safety outcome was the composite of major or clinically relevant non-major bleeding. Results Three thousand one hundred and seventy-three patients with acute infectious diseases leading to hospitalization were randomized to either rivaroxaban (n = 1585) or enoxaparin/placebo (n = 1588), and received at least one dose of study medication. At day 10, primary composite efficacy outcomes did not differ between prophylaxis strategies (rivaroxaban, 2.7%; and enoxaparin, 3.7%). At day 35, there were fewer VTE events with rivaroxaban (4.2%) than with enoxaparin (6.6%) (relative risk [RR] 0.64; 95% confidence interval [CI] 0.45-0.92). Patients with pulmonary infections randomized to rivaroxaban had a lower incidence of VTE both at 10 days (RR 0.50, 95% CI 0.28-0.90) and at 35 days (RR 0.54, 95% CI 0.33-0.87). Primary safety outcome events were increased with rivaroxaban (RR 2.42, 95% CI 1.60-3.66). Conclusions Prolonged rivaroxaban prophylaxis reduced the incidence of VTE in patients hospitalized for acute infectious diseases, particularly those involving the lungs. Efficacy benefits were, in part, offset by bleeding outcomes. ClinicalTrials.gov Number: NCT 00571649.


Asunto(s)
Anticoagulantes/administración & dosificación , Coagulación Sanguínea/efectos de los fármacos , Enoxaparina/administración & dosificación , Inhibidores del Factor Xa/administración & dosificación , Admisión del Paciente , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Rivaroxabán/administración & dosificación , Tromboembolia Venosa/prevención & control , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Anticoagulantes/efectos adversos , Esquema de Medicación , Enoxaparina/efectos adversos , Inhibidores del Factor Xa/efectos adversos , Femenino , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Infecciones del Sistema Respiratorio/sangre , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/epidemiología , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Rivaroxabán/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Tromboembolia Venosa/sangre , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiología
3.
Thromb Res ; 172: 4-8, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30340092

RESUMEN

BACKGROUND: P-selectin - a biomarker of platelet and endothelial cell activation is elevated in patients with non-valvular atrial fibrillation (NVAF). However, the association between sP-selectin level and thromboembolic complications in NVAF patients remains controversial. We tested the hypothesis that plasma soluble P-selectin (sPSL) level correlates with the measures of left atrial blood stasis in NVAF. METHODS: Plasma sPSL concentration was measured using solid-phase ELISA in 103 NVAF patients (age 63 ±â€¯14 years; 26% women) and 48 normal sinus rhythm controls (NSR; age 64 ±â€¯14 years; 41% women) who were not on aspirin. Within the group of NVAF cases, 27 had no spontaneous echocardiographic contrast (SEC) detected by transesophageal echocardiography, 31had mild SEC, 15 moderate, 20 severe, and 10 patients had left atrial appendage thrombus (LAAT). RESULTS: The median soluble sPSL level was higher in NVAF cases compared to NSR controls [(interquartile range) 26 (20-32) ng/mL vs 22 (15-29) ng/mL, p = 0.0045]. Only NVAF patients with CHA2DS2-VASc score ≥ 1 had higher sPSL level compared to NSR controls. Patients with severe SEC had significantly higher sPSL levels [32 (24-38) ng/mL] compared to all other NVAF patients (p = 0.0042) and to NSR controls (p < 0.0001). Also NVAF patients with LAAT had higher sPSL level compared to NSR controls. CONCLUSIONS: There is a direct correlation between p-selectin level and severe blood stasis in the left atrium. Only NVAF patients with CHA2DS2-VASc score ≥ 1 or with LAAT had higher sPSL level compared to NSR controls.


Asunto(s)
Fibrilación Atrial/sangre , Fibrilación Atrial/complicaciones , Selectina-P/sangre , Trombosis/sangre , Trombosis/etiología , Anciano , Apéndice Atrial/patología , Fibrilación Atrial/patología , Ecocardiografía , Femenino , Atrios Cardíacos/patología , Humanos , Masculino , Persona de Mediana Edad , Trombosis/patología
4.
Int Angiol ; 26(1): 67-71, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17353891

RESUMEN

AIM: Inflammatory bowel disease (IBD) has long been considered a risk factor for venous thromboembolism (VTE). Whereas most patients have persistent venous valvular dysfunction following lower extremity deep venous thrombosis (DVT), we hypothesized that patients with IBD would have an increased prevalence of valvular incompetence and changes of chronic DVT (reduced venous caliber with thickened walls) relative to patients with irritable bowel syndrome (IBS) or normal volunteers. METHODS: Subjects with confirmed IBD, clinical features of IBS or normal volunteers underwent complete, prospective duplex ultrasound assessment of their lower extremity venous vascular system. The sonographer performing the venous study was blinded to the clinical diagnosis of the patients. Valvular incompetence was graded as mild, moderate or severe based on accepted criteria. RESULTS: Eighty patients with IBD (ulcerative colitis, UC: 66; Crohn's disease: 14), 80 patients with IBS, and 80 healthy volunteers agreed to participate. One patient with UC was found to have non-occlusive chronic DVT within the left superficial femoral vein. Mild and moderate valvular incompetence was evenly distributed between the 3 groups. No patients met criteria for either acute DVT or severe venous incompetence. CONCLUSION: In patients with IBD, neither valvular incompetence nor chronic venous obstruction are over-represented compared to patients with IBS or normal volunteers. In this prospective assessment of venous physiology by duplex ultrasound, we were not able to confirm prior reports that IBD is a major risk factor for VTE.


Asunto(s)
Enfermedades Inflamatorias del Intestino/complicaciones , Síndrome del Colon Irritable/complicaciones , Extremidad Inferior/irrigación sanguínea , Tromboembolia/etiología , Trombosis de la Vena/etiología , Adulto , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/diagnóstico por imagen , Enfermedades Inflamatorias del Intestino/epidemiología , Síndrome del Colon Irritable/diagnóstico por imagen , Síndrome del Colon Irritable/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Tromboembolia/diagnóstico por imagen , Tromboembolia/epidemiología , Ultrasonografía Doppler Dúplex , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/epidemiología
5.
Eur J Intern Med ; 30: 77-81, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26970916

RESUMEN

INTRODUCTION: While Factor V Leiden (F5 rs6025 A allele) is a known venous thromboembolism (VTE) risk factor, VTE risk among heterozygous vs. homozygous carriers is uncertain. MATERIALS AND METHODS: In a retrospective cohort study of Mayo Clinic patients referred for genotyping between 1996 and 2013, we tested Factor V Leiden genotype as a risk factor for incident and recurrent VTE. RESULTS: Among heterozygous (n=268) and homozygous (n=111) carriers, the prevalence of VTE was 54% and 68%, respectively (p=0.016). While mean patient age at first VTE event (43.9 vs. 42.9years; p=0.70) did not differ significantly, median VTE-free survival was modestly shorter for homozygous carriers (56.8 vs 59.5 years; p=0.04). Sixty-nine (48%) and 31 (42%) heterozygous and homozygous carriers had ≥1 VTE recurrence (p=0.42). In a multivariable model, idiopathic incident VTE and a second thrombophilia were associated with increased and anticoagulation duration >6months with reduced hazards of VTE recurrence; Factor V Leiden genotype was not an independent predictor of recurrence. CONCLUSIONS: Aside from a higher VTE prevalence and modestly reduced VTE-free survival, VTE penetrance and phenotype severity did not differ significantly among homozygous vs. heterozygous carriers, suggesting that VTE prophylaxis and management should not differ by Factor V Leiden genotype.


Asunto(s)
Factor V/genética , Heterocigoto , Homocigoto , Trombofilia/genética , Tromboembolia Venosa/genética , Trombosis de la Vena/genética , Adulto , Anciano , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Mutación , Modelos de Riesgos Proporcionales , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos , Tromboembolia Venosa/complicaciones
6.
J Thromb Haemost ; 2(10): 1834-41, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15456496

RESUMEN

Although the central role of thrombin in arterial thrombosis is well established, the efficacy of vitamin K-dependent factor depletion by warfarin at preventing this process has not been established. To assess the efficacy of warfarin in the prevention of arterial thrombosis, two intensities of anticoagulation were compared in a well-characterized porcine model of carotid angioplasty. For 10 days prior to angioplasty, pigs received either high-dose warfarin (n = 9), low-dose warfarin plus aspirin (n = 9), or control tablets (n = 10). Injured arteries were assessed for (111)In-platelet ( x 10(6) cm(-2)) and (125)I-fibrin(ogen) (molecules x 10(12) cm(-2)) deposition and the incidence of macroscopic thrombus. Platelet (30 +/- 7 vs. 332 +/- 137; P = 0.001) and fibrinogen (156 +/- 17 vs. 365 +/- 90; P < 0.05) deposition were significantly reduced in animals receiving high-intensity warfarin whereas low-intensity warfarin/ASA (520 +/- 240 and 1193 +/- 638) was similar to control (P =NS). At the time of angioplasty, the PT-INR and vitamin K-dependent factors varied over a broad range. The greatest reduction of platelet and fibrinogen deposition occurred as the PT-INR increased from 1.0 to 2.2. Increasing the PT-INR beyond 3.0 resulted in little, if any, incremental reduction of either platelet or fibrinogen deposition. Macroscopic thrombus was abolished at PT-INR > 2.2. Despite a broad range of vitamin K factor activities, no single factor was predictive of either platelet or fibrinogen deposition. Warfarin at PT-INR > 2.2 effectively eliminates thrombosis following deep arterial injury. Arterial thrombosis correlates poorly with any single vitamin K-dependent factor but rather appears to be a function of the entire extrinsic coagulation pathway as measured by the PT-INR.


Asunto(s)
Arterias/lesiones , Factores de Coagulación Sanguínea/antagonistas & inhibidores , Trombosis/prevención & control , Warfarina/farmacología , Angioplastia/efectos adversos , Animales , Aspirina/uso terapéutico , Factores de Coagulación Sanguínea/metabolismo , Plaquetas/patología , Relación Dosis-Respuesta a Droga , Fibrinógeno/metabolismo , Relación Normalizada Internacional , Adhesividad Plaquetaria , Porcinos , Trombosis/tratamiento farmacológico , Trombosis/etiología , Vitamina K , Warfarina/administración & dosificación
7.
J Thromb Haemost ; 1(6): 1296-303, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12871333

RESUMEN

BACKGROUND/OBJECTIVE: To test the hypothesis that circulating platelets display evidence of interactions with atherogenesis, platelet capacity to express P-selectin and propensity for spontaneous microaggregation in vitro were measured in samples from normal donors (N), patients with asymptomatic advanced coronary calcification (CC) or acute coronary syndromes (AC). To measure the effect of angioplasty on platelet function, samples obtained before, 30 min after and 24 h after angioplasty were compared. PATIENTS/METHODS: Platelet P-selectin was measured after maximal stimulation with thrombin. Microaggregation was measured as a platelet count deficit in citrate-anticoagulated platelet-rich plasma (PRP) relative to EDTA-anticoagulated blood. RESULTS: P-selectin expression was significantly lower for platelets from patients with either AC or CC compared to normals. In addition, platelets from AC and CC patients have a significantly greater propensity to form microaggregates in citrate anticoagulant. After angioplasty, the PRP-platelet count decreased transiently. CONCLUSION: Both acute unstable and chronic stable coronary disease are associated with an increased share of platelets unable to express P-selectin and an increased share of platelets that microaggregate in citrate anticoagulant. The genesis of these platelet characteristics is not fully explained by focal acute arterial injury and may reflect exposure to systemic atherosclerosis or the atherogenic process.


Asunto(s)
Plaquetas/patología , Enfermedad de la Arteria Coronaria/sangre , Angioplastia/efectos adversos , Arteriosclerosis/sangre , Arteriosclerosis/patología , Plaquetas/química , Estudios de Casos y Controles , Humanos , Selectina-P/análisis , Agregación Plaquetaria , Pruebas de Función Plaquetaria , Trombina/farmacología
8.
J Thromb Haemost ; 2(12): 2162-9, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15613022

RESUMEN

BACKGROUND/OBJECTIVE: The efficacy of a direct factor (F)Xa inhibitor, ZK-807834, was compared with indirect inhibition by enoxaparin for inhibition and deaggregation of acute platelet-rich thrombi in a well-characterized porcine carotid injury model. METHODS: A crush injury was performed on a randomly chosen carotid artery and the thrombus allowed to propagate for 30 min. Pigs then received intravenous drug for 35 min: ZK-807834-Dose 1 (40 microg kg(-1) bolus + 1.5 microg kg(-1) min(-1) infusion, n=6); ZK-807834-Dose 2 (20 microg kg(-1) bolus + 0.75 microg kg(-1) min(-1) infusion; n=6); enoxaparin (1 mg kg(-1) bolus; n=6); or saline (n=6). Five minutes after drug initiation, the contralateral artery was injured. Thrombus size was monitored by scintillation detection of autologous 111In-platelets. RESULTS: The prothrombin time ratio was 2.2 +/- 0.1; 1.4 +/- 0.3; 1.2 +/- 0.9 and 1.1 +/- 0.2, respectively. ZK-807834-Dose 1 significantly inhibited carotid platelet deposition (525 +/- 226 x 10(6) cm(-2); P = 0.008), whereas ZK-807834-Dose 2 (2325 +/- 768) and enoxaparin (1236 +/- 383) were not different from saline (2776 +/- 642). Thrombus deaggregation was greatest for animals receiving ZK-807834-Dose 1 (473 +/- 185). Neither ZK-807834-Dose 2 (1588 +/- 480) nor enoxaparin (1618 +/- 686) was different from saline control (2222 +/- 598). CONCLUSIONS: Direct FXa inhibition with ZK-807834, at a prothrombin time ratio of 2.2, effectively inhibits thrombosis and promptly deaggregates thrombi induced by arterial injury. In contrast, indirect FXa inhibition with enoxaparin was ineffective.


Asunto(s)
Plaquetas/metabolismo , Arterias Carótidas/patología , Trombosis de las Arterias Carótidas/tratamiento farmacológico , Trombosis de las Arterias Carótidas/prevención & control , Amidinas/farmacología , Animales , Anticoagulantes/farmacología , Relación Dosis-Respuesta a Droga , Enoxaparina/farmacología , Inhibidores del Factor Xa , Femenino , Heparina/metabolismo , Concentración 50 Inhibidora , Perfusión , Tiempo de Protrombina , Piridinas/farmacología , Porcinos , Trombosis/tratamiento farmacológico , Trombosis/prevención & control , Factores de Tiempo
9.
J Thromb Haemost ; 2(9): 1637-44, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15333042

RESUMEN

BACKGROUND/OBJECTIVE: Thromboembolism secondary to atrial fibrillation accounts for approximately one-fourth of all strokes. Although considerable resources have been targeted to pharmacologic prophylaxis, neither the cellular nor the biochemical composition of atrial thrombi is known. Quantitative immunohistochemistry was undertaken to define the composition of atrial thrombi and to explore morphological differences between atrial appendage thrombi and those that embolize. PATIENTS/METHODS: Serial sections of thrombi obtained during valve replacement surgery or embolectomy from 22 patients with atrial fibrillation were stained with antibodies against fibrin, integrin beta3, or tissue factor and analyzed with NIH-image. RESULTS: Thrombi showed distinct regions staining for either fibrin or platelets and on average, the fibrin-rich regions predominated (P < 0.0001). The platelet content of embolized thrombi was nearly twice that of atrial thrombi (P = 0.02). Non-staining amorphous material comprised nearly half of atrial thrombi in situ, but was rare in embolized thrombi (P < 0.001). Tissue factor colocalized to areas rich in platelets and granulocytes. CONCLUSIONS: The abundance of fibrin relative to platelets underscores the enhanced efficacy of warfarin prophylaxis in clinical trials. The finding of tissue factor localized to platelet-leukocyte clusters suggests its blood-borne origin. Compositional differences between in situ and embolized thrombi suggest directions for investigating propensity for embolization.


Asunto(s)
Fibrilación Atrial/complicaciones , Tromboembolia/etiología , Tromboembolia/metabolismo , Trombosis/etiología , Trombosis/metabolismo , Anciano , Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Plaquetas/patología , Femenino , Fibrina/metabolismo , Prótesis Valvulares Cardíacas , Humanos , Inmunohistoquímica , Integrina beta3/metabolismo , Masculino , Tromboembolia/patología , Tromboembolia/prevención & control , Tromboplastina/metabolismo , Trombosis/patología , Trombosis/prevención & control , Warfarina/uso terapéutico
10.
Thromb Haemost ; 84(1): 83-7, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10928475

RESUMEN

The assumption that fibrin and crosslinked fibrin impart irreversibility to arterial thrombi is explored with procedure developed for measuring changes in platelet function, morphology and fibrinogen metabolism in aging occlusive thrombi, in which the condition of stasis is imposed uniformly. Arterial thrombi containing autologous (111)In labeled platelets were generated in vivo by bilateral mechanical injury of porcine carotid arteries. Vessels containing the platelet-rich thrombi were harvested and incubated intact (37 degrees C) for intervals ranging from 30 min to 12 h. The isolated vessels were then bisected and agitated in culture medium containing tick anticoagulant and hirudin for 60 min. Disaggregated platelets were evaluated for yield (from (111)In radioactivity) viability (dense body ATP secretion) and morphology (electron microscopy). Western analysis of fibrin(ogen) in thrombus extracts was performed using anti-fibrinogen Bbeta- and gamma-chain monoclonal antibodies for thrombi at each time point. A stable recovery of nearly 50% of platelets was observed during 12 h of thrombus aging. As thrombi aged, viability of disaggregated platelets gradually decreased with platelet necrosis the predominant feature beyond 6 h. By western analysis of thrombus extracts, nearly 50% of fibrinogen was cleaved to fibrin and extensively crosslinked within 30 min of injury with no evidence of fibrinolysis. With the exception of a declining proportion of gamma-monomer, these features remain relatively constant during 12 h of thrombus maturation. It is concluded that neither fibrin nor crosslinked fibrin are dominant factors imparting cohesion within platelet thrombi. Furthermore, under conditions of complete arterial occlusion imposed by this experimental design, there is no evidence of endogenous fibrinolysis.


Asunto(s)
Plaquetas/fisiología , Trombosis de las Arterias Carótidas/metabolismo , Fibrina/metabolismo , Fibrinógeno/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Proteínas de Artrópodos , Traumatismos de las Arterias Carótidas/complicaciones , Traumatismos de las Arterias Carótidas/etiología , Trombosis de las Arterias Carótidas/etiología , Gránulos Citoplasmáticos/química , Fibrina/química , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Fibrinógeno/química , Fibrinólisis , Fibrinolíticos/farmacología , Hirudinas/análogos & derivados , Hirudinas/farmacología , Péptidos y Proteínas de Señalización Intercelular , Necrosis , Péptidos/farmacología , Proteínas Recombinantes/farmacología , Porcinos , Factores de Tiempo
11.
Thromb Haemost ; 74(3): 879-85, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8571315

RESUMEN

Endogenously activated protein C is evaluated for antithrombotic activity in porcine carotid arteries subjected to mechanical trauma. Protein C is activated by intravenous administration of guanidinobenzoyl-thrombin, which binds to thrombomodulin and there deacylates to yield thrombin. The bound, transiently active thrombin yields a peak of anticoagulant activity between 5 and 10 min after infusion of the latent thrombin. Inhibition of thrombin binding in vivo by co-infusing and active-site-blocked thrombin preparation elicits acute and lethal systemic thrombosis. Nearly occlusive platelet thrombosis, which occurs within 30 min of crushing 1 cm segments of carotid arteries with a standard hemostat, is blocked by endogenous protein C activation initiated 2 min before the crush injury. It is concluded that activated protein C blocks thrombosis is deeply injured musculo-elastic arteries, and that activation of latent thrombin bound to thrombomodulin in vivo is a practical means for delivery of pharmacologically effective concentrations of activated protein C.


Asunto(s)
Anticoagulantes/farmacología , Fibrinolíticos/farmacología , Heparina/farmacología , Hirudinas/farmacología , Proteína C/efectos de los fármacos , Trombina/farmacología , Animales , Traumatismos de las Arterias Carótidas , Femenino , Recuento de Plaquetas/efectos de los fármacos , Porcinos
12.
Mayo Clin Proc ; 76(3): 260-6, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11243272

RESUMEN

OBJECTIVES: To determine the safety and efficacy of intravenously administered phytonadione (vitamin K1) in patients on routine oral warfarin anticoagulation. PATIENTS AND METHODS: This retrospective cohort study comprised adults who were taking warfarin, were not bleeding, and received intravenous phytonadione anticoagulation therapy before a diagnostic or therapeutic procedure between September 1, 1994, and March 31, 1996. The main outcome measures were adverse reactions to intravenously administered phytonadione, prothrombin-international normalized ratio time values, the incidence of bleeding and thrombosis after the procedure, and the time between the procedure and return to anticoagulation after resumption of warfarin treatment. RESULTS: Two (1.9%) of the 105 patients studied had suspected adverse reactions to intravenous phytonadione (dyspnea and chest tightness during infusion in both). For the 82 patients who underwent a procedure, the median time from phytonadione to procedure onset was 27 hours (range, 0.7-147 hours), which was significantly less for patients receiving an initial phytonadione dose of more than 1 mg (P=.009). None had thromboembolism after surgery, although 2 (2.4%) of the 82 patients had procedure-associated major bleeding. For the 60 patients resuming warfarin therapy after a procedure, the median time to return to therapeutic anticoagulation was 4.1 days (range, 0.8-31.7 days) and was unaffected by the phytonadione dosage. CONCLUSIONS: Intravenous phytonadione appears to be safe and is effective for semiurgent correction of long-term oral anticoagulation therapy before surgery. In small doses, it does not prolong the patient's time to return to therapeutic anticoagulation.


Asunto(s)
Anticoagulantes/efectos adversos , Hemorragia/prevención & control , Vitamina K 1/uso terapéutico , Warfarina/efectos adversos , Administración Oral , Adulto , Anciano , Anticoagulantes/administración & dosificación , Estudios de Cohortes , Humanos , Inyecciones Intravenosas , Relación Normalizada Internacional , Persona de Mediana Edad , Cuidados Preoperatorios , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Vitamina K 1/administración & dosificación , Vitamina K 1/efectos adversos , Warfarina/administración & dosificación
13.
Mayo Clin Proc ; 76(12): 1204-12, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11761501

RESUMEN

OBJECTIVE: To describe the causes, complications, and histological appearance of nonbacterial thrombotic endocarditis (NBTE) in a surgical population compared with those in previously reported autopsy series. PATIENTS AND METHODS: Cases were identified by reviewing the surgical pathology reports for all cardiac valvular specimens removed at Mayo Clinic, Rochester, Minn., between 1985 and 2000. Archived microscopic slides and medical records were reviewed for each study patient. RESULTS: The study group consisted of 30 patients (20 female and 10 male), with a mean age of 49 years (range, 15-89 years). Of these 30 patients, 28 had single valve involvement (19 mitral, 8 aortic, and 1 tricuspid), and 2 had involvement of both their mitral and aortic valves. An underlying immune-mediated disorder was identified in 18 patients (60%), including primary antiphospholipid syndrome (in 8), rheumatic heart disease (in 6), systemic lupus erythematosus (in 2), and rheumatoid arthritis (in 2), 15 (83%) of whom were women. Of the remaining 12 patients with no autoimmune disease, only 5 (42%) were women. No patient had metastatic malignant disease or disseminated intravascular coagulopathy. Systemic embolization was documented in 10 patients (33%), 8 of whom had cerebral involvement. Valvular vegetations were visualized by echocardiography before surgery in 8 patients and were suspected but not confirmed preoperatively in 1 patient. All vegetations consisted primarily of platelets and fibrin. The site and appearance of vegetations did not vary with the underlying disease state. CONCLUSIONS: In contrast to previously reported autopsy series, NBTE in a surgical population was more commonly associated with autoimmune disorders than malignancy or disseminated intravascular coagulopathy. Women were affected twice as often as men. Systemic embolization, particularly to the brain, was prominent in both surgical and autopsy series. Vegetations had a similar appearance regardless of the specific underlying disease. An antemortem diagnosis of NBTE in a patient with no known risk factors should prompt a search not only for occult malignancy, as suggested by autopsy studies, but also for autoimmune or rheumatic diseases, particularly the antiphospholipid syndrome.


Asunto(s)
Enfermedades Autoinmunes/complicaciones , Endocarditis , Trombosis , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Síndrome Antifosfolípido/complicaciones , Artritis Reumatoide/complicaciones , Ecocardiografía , Endocarditis/etiología , Endocarditis/patología , Endocarditis/cirugía , Femenino , Humanos , Lupus Eritematoso Sistémico/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Cardiopatía Reumática/complicaciones , Factores de Riesgo , Índice de Severidad de la Enfermedad , Distribución por Sexo , Volumen Sistólico , Trombosis/etiología , Trombosis/patología , Trombosis/cirugía
14.
Mayo Clin Proc ; 75(9): 971-6, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10994834

RESUMEN

Hemostatic aspects of antiphospholipid syndrome (APS) present unique challenges to clinicians and laboratory personnel alike, particularly in the perioperative period. These challenges are especially evident in patients requiring cardiac valve replacement surgery. However, the literature outlining the optimal approach in such patients is limited. We present the case of a 25-year-old woman with severe aortic regurgitation as a result of APS with particular reference to the precautions necessary during perioperative care. Particularly important are the prevention of thrombotic or hemorrhagic complications, management of associated thrombocytopenia, and laboratory methods of perioperative anticoagulation monitoring in the setting of prolonged clotting times.


Asunto(s)
Síndrome Antifosfolípido/complicaciones , Síndrome Antifosfolípido/prevención & control , Insuficiencia de la Válvula Aórtica/etiología , Insuficiencia de la Válvula Aórtica/cirugía , Atención Perioperativa/métodos , Adulto , Anticoagulantes/uso terapéutico , Síndrome Antifosfolípido/sangre , Síndrome Antifosfolípido/diagnóstico , Insuficiencia de la Válvula Aórtica/patología , Pruebas de Coagulación Sanguínea , Monitoreo de Drogas/métodos , Femenino , Hemorragia/etiología , Hemorragia/prevención & control , Hemostasis Quirúrgica/métodos , Heparina/uso terapéutico , Humanos , Trombocitopenia/etiología , Trombocitopenia/prevención & control , Trombosis/etiología , Trombosis/prevención & control
15.
Blood Coagul Fibrinolysis ; 11(3): 243-7, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10870804

RESUMEN

Fechtner syndrome is a rare autosomal dominant disorder consisting of macrothrombocytopenia and leukocyte inclusions, associated with Alport's syndrome (hereditary nephropathy, sensorineural hearing loss, and ocular anomalies). We describe a 71-year-old Caucasian male with a history of hearing loss and asymptomatic macrothrombocytopenia incidentally noted in 1985. Several challenges to hemostasis were uneventful, including total hip arthroplasty. He subsequently developed progressive renal failure, with 'nil lesions' by light and electron microscopy, which was responsive to corticosteroid therapy. Eight family members are affected variably by either thrombocytopenia or renal failure. Laboratory testing gave the following results: hemoglobin, 10.2 g/dl; leukocytes, 5.0 x 109/l; platelets, 64 x 109/l (mean platelet volume, 13.3 fl; normal platelet volume, 7.6-10.8 fl). Peripheral blood smear revealed thrombocytopenia and leukocytes with inclusions. Electron microscopy of the buffy coat confirmed Fechtner inclusions within the patient's leukocytes. Whole mount and thin section electron microscopy revealed a population of large, although not giant, platelets. Despite thrombocytopenia, platelet aggregation was normal. Flow cytometry of dilute platelets revealed normal glycoprotein alphaII beta beta3 activation and alpha-granule p-selectin secretory response to 10 nmol/l human alpha-thrombin. Dense granule adenosine triphosphate secretory response to thrombin was likewise normal. This case illustrates that 'giant' platelets are not universally present in Fechtner syndrome cases, although the platelets are enlarged. Finally, renal pathology other than Alport's nephropathy may be associated with this syndrome.


Asunto(s)
Leucocitos/ultraestructura , Nefritis Hereditaria , Trombocitopenia , Anciano , Humanos , Leucocitos/patología , Masculino , Linaje
17.
J Thromb Haemost ; 7(1): 34-40, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18983495

RESUMEN

BACKGROUND: African Americans with hypertension have higher cardiovascular morbidity and mortality than hypertensives from other ethnic groups. Plasma D-dimer, a fragment generated from fibrin during lysis of mature clot in vivo, is a predictor of adverse cardiovascular events. OBJECTIVE: We investigated whether plasma levels of D-dimer differ between African American (AA) and non-Hispanic white (NHW) adults with hypertension. METHODS: Participants included 933 AA (65 +/- 9 years, 72% women) and 821 NHW (61 +/- 9 years, 56% women) from the community. D-dimer was measured using an immunoturbidimetric assay. Multivariable regression analyses, stratified by gender, were performed to assess whether AA ethnicity was associated with D-dimer levels after adjustment for age, body mass index (BMI), total and high-density lipoprotein (HDL) cholesterol, systolic blood pressure, diabetes, history of smoking, medication (statin and aspirin) use, lifestyle variables (physical activity, alcohol intake, and education), estimated glomerular filtration rate (eGFR), and a marker of inflammation, C-reactive protein (CRP). RESULTS: D-dimer levels were higher in AA men and women than in their NHW counterparts (mean +/- SD; men 256 +/- 199 vs. 190 +/- 183 ng mL(-1), P < 0.001; women, 290 +/- 233 vs. 225 +/- 195 ng mL(-1), P < 0.001). In both sexes, after adjustment for age, conventional risk factors, medication use, and lifestyle variables, AA ethnicity remained associated with higher D-dimer levels (P = 0.002 in men, P = 0.006 in women). These associations remained significant after additional adjustment for eGFR and plasma CRP (P = 0.003 in men, P < 0.0001 in women). CONCLUSIONS: Among adults with hypertension, AA ethnicity was independently associated with higher plasma levels of D-dimer.


Asunto(s)
Negro o Afroamericano , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Hipertensión/etnología , Anciano , Biomarcadores/sangre , Femenino , Humanos , Hipertensión/sangre , Masculino , Persona de Mediana Edad , Nefelometría y Turbidimetría , Análisis de Regresión , Población Blanca
18.
Neurology ; 70(8): 627-33, 2008 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-18285537

RESUMEN

OBJECTIVE: To characterize differences in the prevalence of thrombophilic variables in a large cohort of patients with cerebral venous sinus thrombosis (CVST) and lower extremity deep vein thrombosis (DVT). METHODS: An inception cohort of individuals was identified with first lifetime incident CVST between 1995 and 2005 for whom comprehensive thrombophilia testing was available. To test the hypothesis that thrombophilia prevalence differs with respect to thrombus location, test results were compared to a randomly selected group of patients with lower extremity DVT with comprehensive thrombophilia testing. RESULTS: During this time period, 163 patients with CVST were identified who underwent comprehensive thrombophilia testing. Thrombophilia results were abnormal in 29% including anticardiolipin antibodies (17%), heterozygous factor V Leiden (10%), and heterozygous prothrombin G20210A mutation (n = 14/122; 11%). The prothrombin mutation was more than twice as common in patients with CVST (p = 0.04). Activated protein C resistance, factor V Leiden, and protein C deficiency were more common in patients with DVT (p < 0.05 for each comparison). The anticardiolipin antibodies in patients with CVST were primarily low titer IgM isotype. CONCLUSION: The prevalence of selected thrombophilia factors differs comparing patients with cerebral venous sinus thrombosis and deep vein thrombosis. These differences may offer insights into mechanisms governing the geographic distribution of venous thrombosis.


Asunto(s)
Senos Craneales/patología , Trombofilia/epidemiología , Trombofilia/etiología , Trombosis de la Vena/complicaciones , Trombosis de la Vena/epidemiología , Resistencia a la Proteína C Activada , Adulto , Anticuerpos Anticardiolipina , Estudios de Cohortes , Femenino , Humanos , Incidencia , Extremidad Inferior/patología , Masculino , Persona de Mediana Edad , Prevalencia , Deficiencia de Proteína S , Distribución Aleatoria , Estudios Retrospectivos , Trombofilia/genética , Trombosis de la Vena/genética
19.
Neurology ; 67(5): 814-9, 2006 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-16966543

RESUMEN

OBJECTIVE: To determine whether treatments guidelines for lower extremity venous thrombosis (DVT) could be applied to patients with cerebral venous sinus thrombosis (CVST), the rates of recurrent venous thrombosis and survival for these two diseases were compared. METHODS: The authors studied all patients diagnosed with CVST at the Mayo Clinic between 1978 and 2001. Survival and recurrent venous thrombosis rates (cerebral or noncerebral) were compared with those from patients with DVT. Survival rates were also compared with white US residents. RESULTS: One hundred fifty-four patients (age 40 +/- 19 years) were included (58% women). Warfarin, prescribed in 50% of patients, was continued for an average of 9 months. During a mean of follow up of 36 +/- 47 months (464 patient-years), 20 patients experienced 23 recurrent venous thrombi for an event rate of 5.0/100 patient-years. This recurrence rate was similar to patients with lower extremity DVT (3.8/100 patient-years). Mortality rates were lower for CVST (2.8/100 patient-years) compared with DVT (6.2/100 patient-years; p = 0.001) patients but higher than expected for white US residents (p = 0.001). Increasing age and active malignancy were the only predictors of poor survival. Neither recurrent thrombosis nor survival was influenced by warfarin therapy. CONCLUSIONS: The likelihood of recurrent venous thrombosis is similar after cerebral venous sinus thrombosis (CVST) and lower extremity deep venous thrombosis (DVT). Compared with DVT, survival rates are higher following CVST but are adversely influenced by malignancy and older age.


Asunto(s)
Anticoagulantes/uso terapéutico , Venas Cerebrales/patología , Trombosis de la Vena/epidemiología , Trombosis de la Vena/mortalidad , Adolescente , Adulto , Distribución por Edad , Anciano , Demografía , Femenino , Estudios de Seguimiento , Heparina/uso terapéutico , Humanos , Incidencia , Extremidad Inferior/irrigación sanguínea , Masculino , Persona de Mediana Edad , Recurrencia , Valores de Referencia , Estudios Retrospectivos , Trombofilia/etiología , Trombosis de la Vena/complicaciones , Trombosis de la Vena/tratamiento farmacológico , Warfarina/uso terapéutico
20.
Gastrointest Endosc ; 37(6): 600-3, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1756917

RESUMEN

The unexpected diagnosis of herpetic esophagitis in a patient with nausea led us to review our experience with this disease. Review of our records from 1979 to 1989 produced 23 cases proven by endoscopic culture or microscopic examination (Cowdry-type A inclusions), the largest such series reported to date. Twenty-two of the 23 patients were immunocompromised. Odynophagia and chest pain were each present in half of the cases, but 26% of patients had neither. Gastrointestinal bleeding was attributable to herpetic esophagitis in 30%. Thirty percent of patients had disseminated herpes simplex infection and 70% had simultaneous infections with other organisms. Endoscopic findings included nonspecific inflammation, discrete ulcers, coalescent ulcers, and pseudomembranous esophagitis. Herpes virus was not suspected endoscopically as the cause of esophagitis in 30% of cases. Culture was slightly more sensitive than microscopic examination for diagnosis (89% vs. 76%), but both methods should be employed in any immunocompromised patient with esophagitis.


Asunto(s)
Esofagitis/diagnóstico , Esofagitis/microbiología , Esofagoscopía , Herpes Simple/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Esofagitis/patología , Esófago/patología , Femenino , Herpes Simple/etiología , Herpes Simple/patología , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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