RESUMEN
Cardiopulmonary complications account for approximately 40% of deaths in patients with sickle cell disease (SCD). Diffuse myocardial fibrosis, elevated tricuspid regurgitant jet velocity (TRV) and iron overload are all associated with early mortality. Although HLA-matched sibling hematopoietic cell transplantation (HCT) offers a potential cure, less than 20% of patients have a suitable donor. Haploidentical HCT allows for an increased donor pool and has recently demonstrated improved safety and efficacy. Our group has reported improved cardiac morphology via echocardiography at 1 year after HCT. Here we describe the first use of cardiac magnetic resonance imaging (CMR), the gold standard for measuring volume, mass, and ventricular function, to evaluate changes in cardiac morphology post-HCT in adults with SCD. We analyzed baseline and 1-year data from 12 adults with SCD who underwent nonmyeloablative haploidentical peripheral blood HCT at the National Institutes of Health. Patients underwent noncontrast CMR at 3 T, echocardiography, and laboratory studies. At 1 year after HCT, patients showed marked improvement in cardiac chamber morphology by CMR, including left ventricular (LV) mass (70.2 to 60.1 g/m2; P = .02) and volume (114.5 to 90.6 mL/m2; P = .001). Furthermore, mean TRV normalized by 1 year, suggesting that HCT may offer a survival benefit. Fewer patients had pathologically prolonged native myocardial T1 times, an indirect marker of myocardial fibrosis at 1 year; these data showed a trend toward significance. In this small sample, CMR was very sensitive in detecting cardiac mass and volume changes after HCT and provided complementary information to echocardiography. Notably, post-HCT improvement in cardiac parameters can be attributed only in part to the resolution of anemia; further studies are needed to determine the roles of myocardial fibrosis reversal, improved blood flow, and survival impact after HCT for SCD.
Asunto(s)
Anemia de Células Falciformes , Cardiomiopatías , Trasplante de Células Madre Hematopoyéticas , Estados Unidos , Adulto , Humanos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Anemia de Células Falciformes/diagnóstico por imagen , Anemia de Células Falciformes/terapia , Anemia de Células Falciformes/complicaciones , Imagen por Resonancia Magnética , Ecocardiografía , Cardiomiopatías/complicaciones , FibrosisRESUMEN
Friedreich ataxia is an inherited, progressive, neurodegenerative disorder that is clinically heterogeneous. It is caused by a trinucleotide (GAA) repeat expansion resulting in frataxin loss and oxidative stress. We assessed clinical features including the development of cardiomyopathy and scoliosis and disease progression including loss of ambulation and interference with activities of daily living relative to the length of the GAA repeat, age of onset, and age of diagnosis in a retrospective cohort study of 61 genetically confirmed patients. The use of antioxidants such as vitamins, dietary supplements, and idebenone was also examined. Linear regression and Cox proportional hazard models assessed predictors to disease milestones. The shorter GAA allele accounted for part of the variability in the age of diagnosis (46%) and less in the age of onset (27%). Multivariate analysis demonstrated that age at diagnosis, which may incorporate other genetic and environmental factors, is more important than GAA length in predicting cardiomyopathy, scoliosis, and disease progression.
Asunto(s)
Progresión de la Enfermedad , Ataxia de Friedreich/diagnóstico , Ataxia de Friedreich/genética , Adolescente , Adulto , Anciano , Cardiomiopatías/etiología , Niño , Preescolar , Intervalos de Confianza , Suplementos Dietéticos , Femenino , Ataxia de Friedreich/complicaciones , Ataxia de Friedreich/terapia , Humanos , Entrevista Psicológica , Masculino , Glicoproteínas de Membrana/genética , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Factores de Riesgo , Escoliosis/etiología , Vitaminas/administración & dosificación , Adulto JovenRESUMEN
BACKGROUND: Friedreich's ataxia (FA) is a progressive, multisystem, degenerative disorder caused by a reduction in frataxin. Loss of frataxin results in mitochondrial dysfunction and oxidative damage in patients and model systems. Previous studies have indicated that the antioxidant idebenone (5 mg/kg daily) reduces cardiac hypertrophy, but definite improvement in neurological function has not been shown. METHODS: 48 genetically confirmed FA patients, aged 9-17 years, were enrolled in a 6-month, randomised, double-blind, placebo-controlled study. The patients received placebo or one of three doses of idebenone (approximately 5 mg/kg, 15 mg/kg, and 45 mg/kg), stratified by body weight. The primary endpoint was change from baseline in urinary 8-hydroxy-2'-deoxyguanosine (8OH2'dG), a marker of oxidative DNA damage. Secondary endpoints included changes in the international cooperative ataxia rating scale (ICARS), the FA rating scale (FARS), and a survey of activities of daily living (ADL). This study is registered with ClinicalTrials.gov, number NCT00229632. FINDINGS: Idebenone was generally well tolerated with similar numbers of adverse events in each group. One child receiving high-dose idebenone developed neutropenia after 6 months, which resolved after discontinuation of treatment. 8OH2'dG concentrations were not increased, and did not significantly change with idebenone treatment. Whereas an overall analysis did not show a significant difference in ICARS, FARS, or ADL total scores, there were indications of a dose-dependent response in the ICARS score. A second, pre-specified analysis, excluding patients who required wheelchair assistance, showed a significant improvement in ICARS (Bonferroni p=0.03) and suggested a dose-related response in ICARS, FARS, and ADL scores. INTERPRETATION: Treatment with higher doses of idebenone was generally well tolerated and associated with improvement in neurological function and ADL in patients with FA. The degree of improvement correlated with the dose of idebenone, suggesting that higher doses may be necessary to have a beneficial effect on neurological function.
Asunto(s)
Antioxidantes/uso terapéutico , Benzoquinonas/uso terapéutico , Ataxia de Friedreich/tratamiento farmacológico , Ataxia de Friedreich/fisiopatología , Sistema Nervioso/efectos de los fármacos , Sistema Nervioso/fisiopatología , 8-Hidroxi-2'-Desoxicoguanosina , Actividades Cotidianas , Adolescente , Antioxidantes/administración & dosificación , Antioxidantes/efectos adversos , Benzoquinonas/administración & dosificación , Benzoquinonas/efectos adversos , Niño , Daño del ADN , Desoxiguanosina/análogos & derivados , Desoxiguanosina/orina , Relación Dosis-Respuesta a Droga , Femenino , Ataxia de Friedreich/genética , Ataxia de Friedreich/orina , Humanos , Masculino , Neutropenia/inducido químicamente , Índice de Severidad de la Enfermedad , Ubiquinona/análogos & derivadosRESUMEN
Surface electrical stimulation is currently used in therapy for swallowing problems, although little is known about its physiological effects on neck muscles or swallowing. Previously, when one surface electrode placement was used in dysphagic patients at rest, it lowered the hyolaryngeal complex. Here we examined the effects of nine other placements in normal volunteers to determine 1) whether movements induced by surface stimulation using other placements differ, and 2) whether lowering the hyolaryngeal complex by surface electrical stimulation interfered with swallowing in healthy adults. Ten bipolar surface electrode placements overlying the submental and laryngeal regions were tested. Maximum tolerated stimulation levels were applied at rest while participants held their mouths closed. Videofluoroscopic recordings were used to measure hyoid bone and subglottic air column (laryngeal) movements from resting position and while swallowing 5 ml of liquid barium, with and without stimulation. Videofluoroscopic recordings of swallows were rated blind to condition using the National Institutes of Health-Swallowing Safety Scale. Significant (P < 0.0001) laryngeal and hyoid descent occurred with stimulation at rest. During swallowing, significant (P Asunto(s)
Deglución/fisiología
, Terapia por Estimulación Eléctrica/métodos
, Estimulación Eléctrica/métodos
, Hueso Hioides/fisiología
, Laringe/fisiología
, Movimiento/fisiología
, Músculos del Cuello/fisiología
, Adulto
, Trastornos de Deglución/diagnóstico por imagen
, Trastornos de Deglución/fisiopatología
, Trastornos de Deglución/terapia
, Femenino
, Humanos
, Hueso Hioides/diagnóstico por imagen
, Laringe/diagnóstico por imagen
, Masculino
, Persona de Mediana Edad
, Músculos del Cuello/diagnóstico por imagen
, Músculos del Cuello/inervación
, Radiografía
, Valores de Referencia
, Descanso/fisiología