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1.
Clin Podiatr Med Surg ; 41(3): 607-617, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38789173

RESUMEN

Every surgeon may have experienced a tragic event associated with death or debilitation secondary to deep vein thrombosis (DVT) or pulmonary embolism (PE) after foot and ankle trauma and surgery. Nevertheless, the prevention of such a tragic event needs to be carefully evaluated rationally with currently available epidemiologic data. With great postoperative protocols and access to care, most PE events can be prevented. There are modifiable risk factors, such as length/type of immobilization and operative trauma/time that can lower the incidence of DVT/PE. In addition, chemical prophylaxis may be warranted in certain people within the foot and ankle trauma population.


Asunto(s)
Traumatismos del Tobillo , Traumatismos de los Pies , Tromboembolia Venosa , Humanos , Traumatismos del Tobillo/complicaciones , Traumatismos del Tobillo/cirugía , Traumatismos de los Pies/complicaciones , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control , Factores de Riesgo , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Embolia Pulmonar/etiología , Embolia Pulmonar/prevención & control , Embolia Pulmonar/terapia , Anticoagulantes/uso terapéutico , Incidencia
2.
Drug Saf ; 38(11): 1103-13, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26188764

RESUMEN

INTRODUCTION: Subjects with autosomal dominant polycystic kidney disease (ADPKD) who were taking tolvaptan experienced aminotransferase elevations more frequently than those on placebo in the TEMPO 3:4 (Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and its Outcomes) clinical trial. METHODS: An independent, blinded, expert Hepatic Adjudication Committee re-examined data from TEMPO 3:4 and its open-label extension TEMPO 4:4, as well as from long-term (>14 months) non-ADPKD tolvaptan trials, using the 5-point Drug-Induced Liver Injury Network classification. RESULTS: In TEMPO 3:4, 1445 subjects were randomized 2:1 (tolvaptan vs. placebo) and 1441 had post-baseline assessments of hepatic injury. Sixteen patients on tolvaptan and one on placebo had significant aminotransferase elevations judged to be at least probably related to study drug. No association with dose or systemic exposure was found. Two of 957 subjects taking tolvaptan (0.2 %) and zero of 484 taking placebo met the definition of a Hy's Law case. One additional Hy's Law case was identified in a TEMPO 4:4 subject who had received placebo in the lead study. The onset of a hepatocellular injury occurred between 3 and 18 months after starting tolvaptan, with gradual resolution over the subsequent 1-4 months. None of the events were associated with liver failure or chronic liver injury/dysfunction. No imbalance in hepatic events was observed between tolvaptan and placebo in lower-dose clinical trials of patients with hyponatremia, heart failure, or cirrhosis. CONCLUSIONS: Although hepatocellular injury following long-term tolvaptan treatment in ADPKD subjects was infrequent and reversible, the potential for serious irreversible injury exists. Regular monitoring of transaminase levels is warranted in this patient population.


Asunto(s)
Benzazepinas/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/epidemiología , Bases de Datos Factuales/estadística & datos numéricos , Riñón Poliquístico Autosómico Dominante/epidemiología , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Estadística como Asunto/métodos , Adulto , Antagonistas de los Receptores de Hormonas Antidiuréticas/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Riñón Poliquístico Autosómico Dominante/diagnóstico , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Estudios Retrospectivos , Tolvaptán
3.
J Phys Chem B ; 118(5): 1246-55, 2014 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-24417356

RESUMEN

Current in vitro methods to assess nanomaterial cytotoxicity involve various assays to monitor specific cellular dysfunction, such as metabolic imbalance or inflammation. Although high throughput, fast, and animal-free, these in vitro methods suffer from unreliability and lack of relevance to in vivo situations. New approaches, especially with the potential to reliably relate to in vivo studies directly, are in critical need. This work introduces a new approach, single cell mechanics, derived from atomic force microscopy-based single cell compression. The single cell based approach is intrinsically advantageous in terms of being able to directly correlate to in vivo investigations. Its reliability and potential to measure cytotoxicity is evaluated using known systems: zinc oxide (ZnO) and silicon dioxide (SiO2) nanoparticles (NP) on human aortic endothelial cells (HAECs). This investigation clearly indicates the reliability of single cell compression. For example, ZnO NPs cause significant changes in force vs relative deformation profiles, whereas SiO2 NPs do not. New insights into NPs-cell interactions pertaining to cytotoxicity are also revealed from this single cell mechanics approach, in addition to a qualitative cytotoxicity conclusion. The advantages and disadvantages of this approach are also compared with conventional cytotoxicity assays.


Asunto(s)
Supervivencia Celular/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Forma de la Célula/efectos de los fármacos , Módulo de Elasticidad , Células Endoteliales de la Vena Umbilical Humana , Humanos , Nanopartículas del Metal/química , Microscopía de Fuerza Atómica , Dióxido de Silicio/química , Análisis de la Célula Individual , Óxido de Zinc/química
4.
J Cardiovasc Med (Hagerstown) ; 13(7): 415-22, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22673023

RESUMEN

AIMS: Although congestion is the main reason for admission in patients with worsening acute heart failure syndromes, patients presenting with low SBP and renal impairment often do not respond adequately to and may not tolerate traditional diuretic therapy. We sought to determine the short-term hemodynamic effects of tolvaptan in this high-risk population. METHODS: In a subset analysis of the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study with Tolvaptan trial, 759 patients (18% of total) had elevated blood urea nitrogen (BUN) (> 20  mg/dl) and low SBP (<105  mmHg) at admission. Of these, 386 were randomized to tolvaptan and 373 to placebo. RESULTS: Demographics and baseline characteristics were similar in both groups. Greater reductions from baseline in body weight were observed for tolvaptan (1.63 ±â€Š 2.00 vs. 0.76  ±â€Š 1.75  kg, P  <  0.0001 at day 1 and 3.23  ±  3.36 vs. 2.10  ±â€Š 3.47  kg, P  <  0.0001 at day 7 or discharge). Greater increases in serum sodium concentration were also observed in the tolvaptan group as early as day 1 (4.41  ±  3.67 vs. 1.32  ±â€Š 3.93  mEq/l, P  <  0.0001) and persisted through day 7 or discharge (4.79  ±â€Š 4.89 vs. 1.25  ±â€Š 5.00  mEq/l, P  <  0.0001). Similarly, improvements in patient-reported dyspnea and investigator-assessed orthopnea were significantly greater in the tolvaptan group as early as day 1 of treatment. These changes were not associated with significant differences in heart rate, SBP, DBP or serum creatinine between patients in the two treatment groups during hospitalization. In-hospital mortality rates (total and cause-specific) were comparable to patients who had presented with SBP more than 105  mmHg and BUN less than 20  mg/dl. CONCLUSION: In this subgroup analysis of patients with hypotension and renal impairment, tolvaptan improved symptoms, reduced body weight and increased serum sodium as early as inpatient day 1 without adversely affecting blood pressure or renal function.


Asunto(s)
Benzazepinas/uso terapéutico , Fármacos Cardiovasculares/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Hipotensión/etiología , Insuficiencia Renal/etiología , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Antagonistas de los Receptores de Hormonas Antidiuréticas , Benzazepinas/administración & dosificación , Benzazepinas/efectos adversos , Fármacos Cardiovasculares/administración & dosificación , Fármacos Cardiovasculares/efectos adversos , Diuréticos/uso terapéutico , Método Doble Ciego , Quimioterapia Combinada , Femenino , Furosemida/uso terapéutico , Insuficiencia Cardíaca/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Sodio/sangre , Tolvaptán , Resultado del Tratamiento
5.
J Card Fail ; 17(12): 973-81, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22123358

RESUMEN

BACKGROUND: Increased vasopressin levels may be present in patient with chronic heart failure (HF) and contribute to pathophysiology through effects on the vasopressin V2 receptor. The presence of background diuretic therapy may confound evaluations of vasopressin receptor antagonists (VRA). METHODS AND RESULTS: Eligible patients had HF (New York Heart Association Class II-III), systolic dysfunction (left ventricular ejection fraction ≤0.40) and signs of congestion (eg, edema, rales). At screening, patients were removed from baseline diuretic therapy and placed on a low-sodium diet (2 g/day). After a 2-day run-in period, 83 patients were randomized to placebo (n = 21), monotherapy with the vasopressin V2 receptor antagonist tolvaptan (TLV) 30 mg (n = 20), monotherapy with furosemide 80 mg (FURO, n = 22) or both TLV 30 mg and FURO 80 mg (n = 20) once daily for 7 days. Patients were on standard background therapy and not fluid-restricted throughout the study. A decrease in body weight of -1.37 ± 1.61, -0.54 ± 1.59, and -1.13 ± 1.49 kg was observed versus baseline for TLV, FURO, and TLV+FURO, respectively, at day 8. At the same point, the placebo group showed a body weight increase of +0.72 ± 2.42 kg versus baseline (P = .0006 for TLV versus placebo). Increases in urine volume from baseline were greater with TLV alone (2646 ± 1503 mL/24 hours) than with FURO (894 ± 853 mL/24 hours, P < .001), or PLC (423 ± 786 mL/24 hours, P < .001), and similar to TLV+FURO (2585 ± 2119 mL/24 hours). An increase in serum sodium within the normal range was also observed in TLV-treated patients (P < .02 versus placebo; P < .01 versus FURO). No changes in serum potassium, other laboratory values, or blood pressure were observed. TLV therapy was well tolerated. CONCLUSIONS: In patients with HF and signs of volume overload, TLV monotherapy without concomitant loop diuretic therapy reduced body weight when compared to placebo without adverse changes in serum electrolytes, during a sodium restricted diet while on background medications including angiotensin-converting enzyme inhibitors and ß-blockers.


Asunto(s)
Benzazepinas/uso terapéutico , Diuréticos/uso terapéutico , Furosemida/uso terapéutico , Insuficiencia Cardíaca Sistólica/tratamiento farmacológico , Antagonistas de los Receptores de Hormonas Antidiuréticas , Peso Corporal/efectos de los fármacos , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadística como Asunto , Volumen Sistólico , Tolvaptán , Vasopresinas/efectos de los fármacos , Función Ventricular Izquierda
6.
Am J Health Syst Pharm ; 68(4): 328-33, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21289328

RESUMEN

PURPOSE: The effect of serum sodium concentration and tolvaptan treatment on length of stay (LOS) in patients hospitalized with heart failure (HF) was evaluated. METHODS: Data for this study were derived from a large, international, Phase III trial of patients hospitalized for HF. Two distinct post hoc analyses were performed, analyzing the association between serum sodium concentration and index hospitalization LOS in normonatremic patients and hyponatremic patients treated with placebo plus standard of care versus tolvaptan. Analysis of covariance models were constructed to adjust for potential variation in care delivery and adjusted for hyponatremia status or treatment. RESULTS: Patients with a baseline serum sodium concentration of <135 meq/L who received placebo had an adjusted mean LOS that was 3.06 days longer than did normonatremic patients (p < 0.001). More severely hyponatremic patients had an adjusted mean LOS 5.18 days longer than did normonatremic patients (p < 0.001). In an analysis of all hyponatremic patients, those receiving tolvaptan had an adjusted mean LOS that was 1.72 days shorter than patients receiving placebo, though this difference was not significant. In more severely hyponatremic patients (serum sodium concentration of <130 meq/L), patients treated with tolvaptan had an adjusted mean LOS 2.12 days shorter than those receiving placebo, but this difference was not significant. CONCLUSION: A secondary analysis of a large, international, Phase III trial of patients hospitalized for HF demonstrated that comorbid hyponatremia was associated with a significant increase in hospital LOS. Treatment of hyponatremia with tolvaptan was associated with reductions in LOS that were not significant.


Asunto(s)
Benzazepinas/uso terapéutico , Cardiotónicos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Hiponatremia/tratamiento farmacológico , Tiempo de Internación/estadística & datos numéricos , Sodio/sangre , Adolescente , Adulto , Antagonistas de los Receptores de Hormonas Antidiuréticas , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/complicaciones , Humanos , Hiponatremia/sangre , Hiponatremia/complicaciones , Tolvaptán
7.
Proc Natl Acad Sci U S A ; 107(31): 13872-7, 2010 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-20643929

RESUMEN

By using a highly sensitive technique of atomic force microscopy-based single-cell compression, the rigidity of cultured N2a and HT22 neuronal cells was measured as a function of amyloid-beta42 (Abeta42) protein treatment. Abeta42 oligomers led to significant cellular stiffening; for example, 90-360% higher force was required to reach 80% deformation for N2a cells. Disaggregated or fibrillar forms of Abeta42 showed much less change. These observations were explained by a combination of two factors: (i) incorporation of oligomer into cellular membrane, which resulted in an increase in the Young's modulus of the membrane from 0.9+/-0.4 to 1.85+/-0.75 MPa for N2a cells and from 1.73+/-0.90 to 5.5+/-1.4 MPa for HT22 cells, and (ii) an increase in intracellular osmotic pressure (e.g., from 7 to 40 Pa for N2a cells) through unregulated ion influx. These findings and measurements provide a deeper, more characteristic, and quantitative insight into interactions between cells and Abeta42 oligomers, which have been considered the prime suspect for initiating neuronal dysfunction in Alzheimer's disease.


Asunto(s)
Péptidos beta-Amiloides/química , Comunicación Celular , Neuronas/química , Animales , Línea Celular , Ratones , Neuronas/fisiología , Dinámicas no Lineales , Multimerización de Proteína
8.
Eur Heart J ; 30(18): 2233-40, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19561338

RESUMEN

AIMS: To describe the effects of tolvaptan therapy on dyspnoea relief based on timing of delivery, influence of concomitant therapies, and baseline patient and clinical characteristics. Also, the influence of clinical trial design on dyspnoea measurement, from the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study with Tolvaptan (EVEREST) trials. METHODS AND RESULTS: Post hoc analysis was performed based on the endpoint of patient-assessed dyspnoea. Changes from baseline at inpatient Day 1 were compared between treatment groups by the van Elteren test. Pre-determined subgroup analyses were also performed. Tolvaptan's effects are greatest within 12 h after first dose with an additional, but modest dyspnoea improvement benefit irrespective of time after admission. Overall, patients continue to report dyspnoea improvement up to 60 h after admission. The window of enrolment, up to 48 h after admission, combined with measurement on 'Day 1' led to a wide range over when dyspnoea was assessed. CONCLUSION: Post hoc analysis suggests that tolvaptan modestly improves dyspnoea compared with standard therapy alone, regardless if given early or relatively late after hospitalization, and also across major pre-specified subgroups, despite ongoing background therapy aimed at relieving signs and symptoms. Significant variability around when dyspnoea was assessed, in addition to the persistence of dyspnoea despite ongoing background therapy, may influence how future clinical trials assess dyspnoea in acute heart failure syndromes.


Asunto(s)
Benzazepinas/administración & dosificación , Disnea/tratamiento farmacológico , Fármacos del Sistema Respiratorio/administración & dosificación , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Atelectasia Pulmonar/etiología , Tolvaptán , Resultado del Tratamiento
9.
Eur Heart J ; 30(13): 1666-73, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19411662

RESUMEN

AIMS: Increases in body weight (BW) are important determinants for hospitalization in ambulatory patients with heart failure (HF), but have not yet been explored in patients hospitalized for worsening HF. We explore the relationship between change in BW after hospitalization for worsening HF and risk for repeat hospitalization and mortality in the EVEREST trial. METHODS AND RESULTS: The EVEREST trial randomized 4133 patients hospitalized for worsening HF and low ejection fraction (< or =40%) to tolvaptan, a vasopressin antagonist, or placebo. Following discharge, BW was assessed at 1, 4, and 8 weeks, and every 8 weeks thereafter. A time-dependent Cox proportional Hazard model explored the relationship between change in BW at 60, 120, and 180 days from discharge and the risks of HF hospitalization, cardiovascular (CV) hospitalization, and all-cause mortality. For subjects re-hospitalized for heart failure at 60, 120, and 180 days after discharge, mean BW increase prior to the event was 1.96, 2.07, and 1.97 kg, respectively, compared with 0.74, 0.90, and 1.04 kg in patients without re-hospitalization (P < 0.001 all groups). A similar pattern was observed with CV hospitalization. However, increases in BW were not predictive of all-cause mortality. CONCLUSION: Increases in BW after hospitalization for worsening HF was predictive of repeat hospitalization events, but not mortality in the post-discharge period.


Asunto(s)
Insuficiencia Cardíaca/fisiopatología , Hospitalización , Aumento de Peso , Anciano , Antagonistas de los Receptores de Hormonas Antidiuréticas , Benzazepinas/uso terapéutico , Progresión de la Enfermedad , Métodos Epidemiológicos , Femenino , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Readmisión del Paciente , Pronóstico , Tolvaptán , Resultado del Tratamiento
10.
J Am Coll Cardiol ; 52(20): 1640-8, 2008 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-18992654

RESUMEN

OBJECTIVES: Our aim was to examine continental and regional differences in baseline characteristics and post-discharge clinical outcomes in the EVEREST (Efficacy of Vasopressin Antagonism in Heart Failure: Outcome Study with Tolvaptan) trial. BACKGROUND: Continental and regional differences in clinical trials of acute heart failure syndromes (AHFS) have not been well studied. METHODS: We analyzed data from the EVEREST trial, which randomized 4,133 patients hospitalized for worsening (HF) and left ventricular ejection fraction < or =40% to oral tolvaptan, a vasopressin antagonist, or placebo and followed for a median of 9.9 months. Baseline characteristics, mortality, and outcomes were analyzed across North America (n = 1,251), South America (n = 688), Western Europe (564 patients), and Eastern Europe (n = 1,619). RESULTS: There were major differences between the 4 groups in the severity, etiology, and management of HF. Unadjusted 1-year mortality and cardiovascular mortality/HF hospitalization were 30.4% and 52.5% in North America, 27.2% and 41.6% in South America, 27.1% and 47.3% in Western Europe, and 20.5% and 35.3% in Eastern Europe. After adjustment, South American patients had the highest overall mortality (hazard ratio: 1.42, 95% confidence interval: 1.15 to 1.76), while Eastern European patients had the lowest cardiovascular death and HF hospitalization rate (hazard ratio: 0.84, 95% confidence interval: 0.73 to 0.97), compared with patients in North America. CONCLUSIONS: Major continental and regional differences in HF severity, etiology, and management exist among AHFS patients, resulting in varied post-discharge outcomes, despite pre-defined selection criteria. These differences should be taken into account when planning global trials in AHFS. (Efficacy of Vasopressin Antagonism in Heart Failure: Outcome Study with Tolvaptan [EVEREST]; NCT00071331).


Asunto(s)
Benzazepinas/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Vasopresinas/antagonistas & inhibidores , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Insuficiencia Cardíaca/etnología , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/cirugía , Hospitalización , Humanos , Internacionalidad , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Revascularización Miocárdica , Marcapaso Artificial/estadística & datos numéricos , Estudios Prospectivos , Tolvaptán
11.
J Am Coll Cardiol ; 52(19): 1540-5, 2008 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-19007589

RESUMEN

OBJECTIVES: This study sought to assess the acute hemodynamic effect of vasopressin V(2) receptor antagonism. BACKGROUND: In decompensated heart failure (HF), tolvaptan, a vasopressin V(2) receptor antagonist, has been shown to improve congestion. It has not yet been established whether these improvements may be associated with the hemodynamic effects of tolvaptan. METHODS: A total of 181 patients with advanced HF on standard therapy were randomized to double-blind treatment with tolvaptan at a single oral dose (15, 30, or 60 mg) or placebo. RESULTS: Tolvaptan at all doses significantly reduced pulmonary capillary wedge pressure (-6.4 +/- 4.1 mm Hg, -5.7 +/- 4.6 mm Hg, -5.7 +/- 4.3 mm Hg, and -4.2 +/- 4.6 mm Hg for the 15-mg, 30-mg, 60-mg, and placebo groups, respectively; p < 0.05 for all tolvaptan vs. placebo). Tolvaptan also reduced right atrial pressure (-4.4 +/- 6.9 mm Hg [p < 0.05], -4.3 +/- 4.0 mm Hg [p < 0.05], -3.5 +/- 3.6 mm Hg, and -3.0 +/- 3.0 mm Hg for the 15-mg, 30-mg, 60-mg, and placebo groups, respectively) and pulmonary artery pressure (-5.6 +/- 4.2 mm Hg, -5.5 +/- 4.1 mm Hg, -5.2 +/- 6.1 mm Hg, and -3.0 +/- 4.7 mm Hg for the 15-mg, 30-mg, 60-mg, and placebo groups, respectively; p < 0.05). Tolvaptan increased urine output by 3 h in a dose-dependent manner (p < 0.0001), without changes in renal function. CONCLUSIONS: In patients with advanced HF, tolvaptan resulted in favorable but modest changes in filling pressures associated with a significant increase in urine output. These data provide mechanistic support for the symptomatic improvements noted with tolvaptan in patients with decompensated HF. (Heart Pressure Assessment Study With Tolvaptan to Treat Congestive Heart Failure; NCT00132886).


Asunto(s)
Antagonistas de los Receptores de Hormonas Antidiuréticas , Benzazepinas/administración & dosificación , Insuficiencia Cardíaca Sistólica/tratamiento farmacológico , Hemodinámica/efectos de los fármacos , Administración Oral , Anciano , Benzazepinas/efectos adversos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca Sistólica/diagnóstico , Insuficiencia Cardíaca Sistólica/mortalidad , Pruebas de Función Cardíaca , Hemodinámica/fisiología , Humanos , Cooperación Internacional , Masculino , Persona de Mediana Edad , Análisis Multivariante , Probabilidad , Estudios Prospectivos , Receptores de Vasopresinas/administración & dosificación , Valores de Referencia , Medición de Riesgo , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Tolvaptán , Resultado del Tratamiento
12.
JAMA ; 299(22): 2656-66, 2008 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-18544725

RESUMEN

CONTEXT: Hospitalization for heart failure is associated with high postdischarge mortality and morbidity. The predictive value of the QRS duration during admission for heart failure has not been well studied. OBJECTIVE: To investigate the predictive value of the QRS duration in patients hospitalized for heart failure with reduced left ventricular ejection fraction (LVEF). DESIGN, SETTING, AND PARTICIPANTS: Retrospective, post hoc analysis from the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST), an event-driven, randomized, double-blind, placebo-controlled study in patients hospitalized for heart failure and having an LVEF of 40% or less. A total of 4133 patients were enrolled at 359 North American, South American, and European sites between October 7, 2003, and February 3, 2006. After excluding 1029 patients with a pacemaker, implantable cardioverter-defibrillator, or both at enrollment and 142 patients without a reported baseline QRS duration, 2962 patients were included in the analysis: 1641 had a normal QRS duration (< 120 ms) and 1321 had a prolonged QRS duration (> or = 120 ms). MAIN OUTCOME MEASURES: Dual primary end points were all-cause mortality and the composite of cardiovascular death or hospitalization for heart failure. RESULTS: During a median follow-up of 9.9 months, all-cause mortality was 18.7% for patients with a normal baseline QRS duration and 28.1% for patients with a prolonged baseline QRS duration (hazard ratio [HR], 1.61; 95% confidence interval [CI], 1.38-1.87). The composite of cardiovascular death or hospitalization for heart failure was 32.4% for patients with a baseline QRS duration less than 120 ms and 41.6% for patients with a baseline QRS duration of 120 ms or greater (HR, 1.40; 95% CI, 1.24-1.58). The increased risk associated with prolonged QRS duration was confirmed after adjusting for multiple variables for all-cause mortality (HR, 1.24; 95% CI, 1.02-1.50) and the composite of cardiovascular death or hospitalization for heart failure (HR, 1.28; 95% CI, 1.10-1.49). Only 105 patients (3.6%) who presented with a prolonged baseline QRS duration had a normal QRS duration on their last inpatient electrocardiogram. CONCLUSION: A prolonged QRS duration appears common in patients with reduced LVEF who are hospitalized for heart failure and is an independent predictor of high postdischarge morbidity and mortality.


Asunto(s)
Insuficiencia Cardíaca/fisiopatología , Frecuencia Cardíaca , Hospitalización , Disfunción Ventricular Izquierda/fisiopatología , Anciano , Causas de Muerte , Electrocardiografía , Femenino , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/terapia , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos
13.
Langmuir ; 24(5): 2232-9, 2008 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-18198912

RESUMEN

Protein microarrays are rapidly emerging as valuable tools in creating combinatorial cell culture systems where inducers of cellular differentiation can be identified in a rapid and multiplexed fashion. In the present study, protein microarraying was combined with photoresist lithography to enable printing of extracellular matrix (ECM) protein arrays while precisely controlling "on-the-spot" cell-cell interactions. In this surface engineering approach, the micropatterned photoresist layer formed on a glass substrate served as a temporary stencil during the microarray printing, defining the micrometer-scale dimensions and the geometry of the cell-adhesion domains within the printed protein spots. After removal of the photoresist, the glass substrates contained micrometer-scale cell-adhesive regions that were encoded within 300 or 500 microm diameter protein domains. Fluorescence microscopy and atomic force microscopy (AFM) were employed to characterize protein micropatterns. When incubated with micropatterned surfaces, hepatic (HepG2) cells attached on 300 or 500 mum diameter protein spots; however, the extent of cell-cell contacts within each spot varied in accordance with dimensions of the photoresist stencil, from single cells attaching on 30 microm diameter features to multicell clusters residing on 100 or 200 microm diameter regions. Importantly, the photoresist removal process was shown to have no detrimental effects on the ability of several ECM proteins (collagens I, II, and IV and laminin) to support functional hepatic cultures. The micropatterning approach described here allows for a small cell population seeded onto a single cell culture substrate to be exposed to multiple scenarios of cell-cell and cell-surface interactions in parallel. This technology will be particularly useful for high-throughput screening of biological stimuli required for tissue specification of stem cells or for maintenance of differentiated phenotype in scarce primary cells.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Análisis por Matrices de Proteínas/métodos , Adhesión Celular , Línea Celular Tumoral , Células Cultivadas , Humanos , Fotoquímica
14.
J Cardiovasc Pharmacol ; 50(2): 213-22, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17703139

RESUMEN

The pharmacokinetic and pharmacodynamic interactions between tolvaptan and furosemide or hydrochlorothiazide (HCTZ) were determined in a single-center, randomized, open-label, parallel-arm, 3-period crossover study conducted in healthy white (Caucasian) men. A total of 12 subjects were enrolled in the study, with 6 subjects assigned to each of two treatment arms. Subjects in Arm 1 received 30 mg of tolvaptan, 80 mg of furosemide, and 30 mg of tolvaptan + 80 mg of furosemide. Subjects in Arm 2 received 30 mg of tolvaptan, 100 mg of HCTZ, and 30 mg pf tolvaptan + 100 mg of HCTZ. Doses were separated by a 48-hour washout. Blood and urine samples were collected at scheduled timepoints during the 24 hours after administration of study drug for the determination of pharmacokinetic and pharmacodynamic parameters. No clinically significant changes were noted in the pharmacokinetic profiles of tolvaptan and furosemide or tolvaptan and HCTZ when coadministered. Free water clearance, 24-hour urine volume, plasma sodium and argentine vasopressin concentrations, and plasma osmolality were higher, and urine osmolality was lower when tolvaptan was administered either alone or in combination with furosemide or HCTZ, compared with furosemide or HCTZ administered alone. At 24 hours postdose, plasma renin activity was increased after furosemide or HCTZ administered alone or with tolvaptan, but it was unchanged after tolvaptan alone. Tolvaptan did not significantly affect the natriuretic activity of furosemide or HCTZ. Furosemide and HCTZ did not significantly affect the aquaretic activity of tolvaptan. Tolvaptan administered alone or in combination with furosemide or HCTZ was safe and well tolerated at the given doses.


Asunto(s)
Benzazepinas/farmacología , Diuréticos/farmacología , Furosemida/farmacología , Hidroclorotiazida/farmacología , Adolescente , Adulto , Antagonistas de los Receptores de Hormonas Antidiuréticas , Arginina Vasopresina/sangre , Arginina Vasopresina/efectos de los fármacos , Benzazepinas/efectos adversos , Benzazepinas/farmacocinética , Estudios Cruzados , Diuréticos/efectos adversos , Diuréticos/farmacocinética , Interacciones Farmacológicas , Furosemida/efectos adversos , Furosemida/farmacocinética , Humanos , Hidroclorotiazida/efectos adversos , Hidroclorotiazida/farmacocinética , Masculino , Concentración Osmolar , Renina/sangre , Renina/efectos de los fármacos , Sodio/sangre , Tolvaptán
15.
J Am Coll Cardiol ; 49(22): 2151-9, 2007 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-17543634

RESUMEN

OBJECTIVES: This study sought to examine the effects of vasopressin V2 receptor antagonism with tolvaptan on the changes in left ventricular (LV) volumes over time. BACKGROUND: Vasopressin levels may be increased in patients with heart failure (HF) and may be a factor driving the progression of HF. METHODS: This was a multicenter, randomized, double-blind, placebo-controlled trial conducted to evaluate the effect of long-term administration of the vasopressin V2-receptor antagonist tolvaptan (30 mg/day) on reducing left ventricular end-diastolic volume (LVEDV) compared with placebo in patients with HF and reduced systolic function, using quantitative radionuclide ventriculography at baseline, repeated after 1 year of therapy, and repeated again approximately 1 week after withdrawal of study drug. RESULTS: A total of 120 patients were randomized to tolvaptan and 120 were randomized to placebo. In the placebo group, there was no change in LVEDV over the course of follow-up (change of 0.0 +/- 10.0 ml/m2). After 1 year of tolvaptan, there was a small reduction in LV volume (decrease of 1.8 +/- 10.7 ml/m2); the between-group difference was not significant (p = 0.21). During the course of the trial, there were 6 deaths (5%) and 21 HF hospitalizations (18%) in the tolvaptan group, compared with 11 deaths (9%) and 34 HF hospitalizations (28%) in the placebo group. In a time-to-event analysis, there was a significant favorable effect of tolvaptan on the composite of mortality or heart failure hospitalization (p < 0.03 by log-rank test). CONCLUSIONS: In a well-treated population of stable HF patients, there was no significant effect of tolvaptan therapy on LV volumes observed during 1 year of therapy. Nonprespecified natural history data favored therapy with tolvaptan, with a reduction in the combined end point of mortality and heart failure hospitalization observed. (Multicenter, Randomized, Double-Blind, Placebo Controlled, Efficacy Study on the Effects of Tolvaptan on Left Ventricular Dilatation in Congestive Heart Failure Patients; http://clinicaltrials.gov/ct/show/NCT00043758?order=1; NCT00043758).


Asunto(s)
Benzazepinas/administración & dosificación , Insuficiencia Cardíaca/tratamiento farmacológico , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos , Administración Oral , Anciano , Antagonistas de los Receptores de Hormonas Antidiuréticas , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Dilatación Patológica/tratamiento farmacológico , Dilatación Patológica/fisiopatología , Método Doble Ciego , Femenino , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Receptores de Vasopresinas/fisiología , Sístole/efectos de los fármacos , Sístole/fisiología , Tolvaptán , Función Ventricular Izquierda/fisiología , Remodelación Ventricular/fisiología
16.
JAMA ; 297(12): 1319-31, 2007 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-17384437

RESUMEN

CONTEXT: Vasopressin mediates fluid retention in heart failure. Tolvaptan, a vasopressin V2 receptor blocker, shows promise for management of heart failure. OBJECTIVE: To investigate the effects of tolvaptan initiated in patients hospitalized with heart failure. DESIGN, SETTING, AND PARTICIPANTS: The Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST), an event-driven, randomized, double-blind, placebo-controlled study. The outcome trial comprised 4133 patients within 2 short-term clinical status studies, who were hospitalized with heart failure, randomized at 359 North American, South American, and European sites between October 7, 2003, and February 3, 2006, and followed up during long-term treatment. INTERVENTION: Within 48 hours of admission, patients were randomly assigned to receive oral tolvaptan, 30 mg once per day (n = 2072), or placebo (n = 2061) for a minimum of 60 days, in addition to standard therapy. MAIN OUTCOME MEASURES: Dual primary end points were all-cause mortality (superiority and noninferiority) and cardiovascular death or hospitalization for heart failure (superiority only). Secondary end points included changes in dyspnea, body weight, and edema. RESULTS: During a median follow-up of 9.9 months, 537 patients (25.9%) in the tolvaptan group and 543 (26.3%) in the placebo group died (hazard ratio, 0.98; 95% confidence interval [CI], 0.87-1.11; P = .68). The upper confidence limit for the mortality difference was within the prespecified noninferiority margin of 1.25 (P<.001). The composite of cardiovascular death or hospitalization for heart failure occurred in 871 tolvaptan group patients (42.0%) and 829 placebo group patients (40.2%; hazard ratio, 1.04; 95% CI, 0.95-1.14; P = .55). Secondary end points of cardiovascular mortality, cardiovascular death or hospitalization, and worsening heart failure were also not different. Tolvaptan significantly improved secondary end points of day 1 patient-assessed dyspnea, day 1 body weight, and day 7 edema. In patients with hyponatremia, serum sodium levels significantly increased. The Kansas City Cardiomyopathy Questionnaire overall summary score was not improved at outpatient week 1, but body weight and serum sodium effects persisted long after discharge. Tolvaptan caused increased thirst and dry mouth, but frequencies of major adverse events were similar in the 2 groups. CONCLUSION: Tolvaptan initiated for acute treatment of patients hospitalized with heart failure had no effect on long-term mortality or heart failure-related morbidity. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00071331


Asunto(s)
Antagonistas de los Receptores de Hormonas Antidiuréticas , Benzazepinas/uso terapéutico , Fármacos Cardiovasculares/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Administración Oral , Anciano , Nitrógeno de la Urea Sanguínea , Peso Corporal/efectos de los fármacos , Creatinina/sangre , Método Doble Ciego , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/mortalidad , Hospitalización , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Calidad de Vida , Sodio/sangre , Tolvaptán
17.
JAMA ; 297(12): 1332-43, 2007 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-17384438

RESUMEN

CONTEXT: Heart failure causes more than 1 million US hospitalizations yearly, mostly related to congestion. Tolvaptan, an oral, nonpeptide, selective vasopressin V2-receptor antagonist, shows promise in this condition. OBJECTIVE: To evaluate short-term effects of tolvaptan when added to standard therapy in patients hospitalized with heart failure. DESIGN, SETTING, AND PATIENTS: Two identical prospective, randomized, double-blind, placebo-controlled trials at 359 sites in North America, South America, and Europe were conducted during the inpatient period of the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST) between October 7, 2003, and February 3, 2006. A total of 2048 (trial A) and 2085 (trial B) patients hospitalized with heart failure and congestion were studied. INTERVENTION: Patients were randomized to receive either tolvaptan (30 mg/d) or matching placebo, within 48 hours of admission. MAIN OUTCOME MEASURES: Primary end point was a composite of changes in global clinical status based on a visual analog scale and body weight at day 7 or discharge if earlier. Secondary end points included dyspnea (day 1), global clinical status (day 7 or discharge), body weight (days 1 and 7 or discharge), and peripheral edema (day 7 or discharge). RESULTS: Rank sum analysis of the composite primary end point showed greater improvement with tolvaptan vs placebo (trial A, mean [SD], 1.06 [0.43] vs 0.99 [0.44]; and trial B, 1.07 [0.42] vs 0.97 [0.43]; both trials P<.001). Mean (SD) body weight reduction was greater with tolvaptan on day 1 (trial A, 1.71 [1.80] vs 0.99 [1.83] kg; P<.001; and trial B, 1.82 [2.01] vs 0.95 [1.85] kg; P<.001) and day 7 or discharge (trial A, 3.35 [3.27] vs 2.73 [3.34] kg; P<.001; and trial B, 3.77 [3.59] vs 2.79 [3.46] kg; P<.001), whereas improvements in global clinical status were not different between groups. More patients receiving tolvaptan (684 [76.7%] and 678 [72.1%] for trial A and trial B, respectively) vs patients receiving placebo (646 [70.6%] and 597 [65.3%], respectively) reported improvement in dyspnea at day 1 (both trials P<.001). Edema at day 7 or discharge improved significantly with tolvaptan in trial B (P = .02) but did not reach significance in trial A (P = .07). Serious adverse event frequencies were similar between groups, without excess renal failure or hypotension. CONCLUSION: In patients hospitalized with heart failure, oral tolvaptan in addition to standard therapy including diuretics improved many, though not all, heart failure signs and symptoms, without serious adverse events. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00071331


Asunto(s)
Antagonistas de los Receptores de Hormonas Antidiuréticas , Benzazepinas/uso terapéutico , Fármacos Cardiovasculares/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Diuréticos/uso terapéutico , Método Doble Ciego , Quimioterapia Combinada , Femenino , Furosemida/uso terapéutico , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Tolvaptán
18.
Am J Physiol Renal Physiol ; 290(2): F273-8, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16189291

RESUMEN

Diuretics are frequently required to treat fluid retention in patients with congestive heart failure (CHF). Unfortunately, they can lead to a decline in renal function, electrolyte depletion, and neurohumoral activation. Arginine vasopressin (AVP) promotes renal water reabsorption via the V2 receptor, and its levels are increased in CHF. This study was designed to assess the effects of a single oral dose of tolvaptan, a selective V2-receptor blocker, in the absence of other medications, on renal function in human CHF and to compare this to the effects of a single oral dose of furosemide. We hypothesized that V2-receptor antagonism would yield a diuresis comparable to furosemide but would not adversely affect renal hemodynamics, plasma electrolyte concentration, or neurohumoral activation in stable human CHF. Renal and neurohumoral effects of tolvaptan and furosemide were assessed in an open-label, randomized, placebo-controlled crossover study in 14 patients with NYHA II-III CHF. Patients received placebo or 30 mg of tolvaptan on day 1 and were crossed over to the other medication on day 3. On day 5, all subjects received 80 mg of furosemide. Tolvaptan and furosemide induced similar diuretic responses. Unlike tolvaptan, furosemide increased urinary sodium and potassium excretion and decreased renal blood flow. Tolvaptan, furosemide, and placebo did not differ with respect to mean arterial pressure, glomerular filtration rate, or serum sodium and potassium. We conclude that tolvaptan is an effective aquaretic with no adverse effects on renal hemodynamics or serum electrolytes in patients with mild to moderate heart failure.


Asunto(s)
Antagonistas de los Receptores de Hormonas Antidiuréticas , Benzazepinas/farmacología , Insuficiencia Cardíaca/tratamiento farmacológico , Potasio/orina , Sodio/orina , Agua/metabolismo , Benzazepinas/administración & dosificación , Estudios Cruzados , Diuréticos/farmacología , Femenino , Furosemida/administración & dosificación , Furosemida/farmacología , Insuficiencia Cardíaca/fisiopatología , Hemodinámica/efectos de los fármacos , Humanos , Riñón/efectos de los fármacos , Riñón/fisiopatología , Masculino , Persona de Mediana Edad , Placebos , Tolvaptán , Micción/efectos de los fármacos , Vasopresinas/fisiología , Equilibrio Hidroelectrolítico/efectos de los fármacos
19.
Future Cardiol ; 2(6): 627-34, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19804253

RESUMEN

Tolvaptan is an oral, once-daily nonpeptide arginine vasopressin V(2)-receptor antagonist under development for the treatment of hyponatremia and congestive heart failure. In Phase II clinical trials, tolvaptan, in addition to standard therapy, increased fluid loss, resulting in decreased body weight and improved edema and serum sodium without affecting blood pressure, heart rate or renal function in patients with heart failure. The compound appeared to be well tolerated and dose-dependent adverse events were generally realated to its pharmacological activity, such as thirst and dry mouth. In patients with hyponatremia, tolvaptan appears to be more effective than fluid restriction at improving sodium levels without an increase in adverse events. An international Phase III outcome study; Efficacy of Vasopressin antagonism in hEaRt failurE outcome Study with Tolvaptan (EVEREST), evaluating the long-term efficacy and safety of tolvaptan in patients hospitalized with worsening heart failure, is currently ongoing.

20.
J Cardiovasc Pharmacol ; 46(5): 609-14, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16220067

RESUMEN

Fluid retention and extracellular volume expansion are frequently encountered complications of congestive heart failure (HF) that can cause morbidity and mortality. Tolvaptan (Otsuka) is an orally administered nonpeptide vasopressin (VP) V2 receptor antagonist that inhibits water reabsorption in the kidney by competitively blocking VP binding, resulting in water diuresis without significantly changing total electrolyte excretion. In the 24-hour period following a 30-mg dose of tolvaptan, urine excretion rate increases and declines as plasma concentrations rise and fall; this uneven effect results in 80% of daily urine output in the first 12 hours. Therefore, the current study was designed to assess the pharmacodynamic effects, pharmacokinetics, and clinical safety of tolvaptan 30 mg QD plus placebo versus 15 mg BID over 7 days in patients with NYHA Class II/III heart failure and persistent fluid overload, SBP > or = 90 mm Hg, and a serum creatinine < or = 3.0 mg/dL. Patients were withdrawn from diuretics for 48 hours before randomization. Statistics were performed with ANCOVA for continuous variables and Mantel-Haenszel mean score test stratified by center for categorical variables. Thirty-nine of 40 patients completed days 1 and 7. There were no significant clinical, pharmacokinetic, or pharmacodynamic differences between the dosing regimens over time. Based on these findings, tolvaptan 30 mg was chosen as the comparator for placebo in a large phase 3 survival trial.


Asunto(s)
Antagonistas de los Receptores de Hormonas Antidiuréticas , Benzazepinas/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Benzazepinas/administración & dosificación , Benzazepinas/efectos adversos , Benzazepinas/farmacocinética , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Insuficiencia Cardíaca/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Tolvaptán , Resultado del Tratamiento
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