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2.
Langmuir ; 35(6): 2196-2208, 2019 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-30590922

RESUMEN

This article describes the preparation of hierarchically structured microsieves via a suitable combination of float-casting and inkjet-printing: A mixture of hydrophobized silica particles of 600 nm ± 20 nm diameter, a suitable non-water-soluble nonvolatile acrylic monomer, a nonvolatile photoinitiator, and volatile organic solvents is applied to a water surface. This mixture spontaneously spreads on the water surface; the volatile solvents evaporate and leave behind a layer of the monomer/initiator mixture comprising a monolayer of particles, each particle protruding out of the monomer layer at the top and bottom surface. Photopolymerization of the monomer converts this mixed layer into a solid composite membrane floating on the water surface. Onto this membrane, while still floating on the water surface, a hierarchical reinforcing structure based on a photocurable ink is inkjet-printed and solidified. In contrast to the nonreinforced membrane, the reinforced membrane can easily be lifted off the water surface without suffering damage. Subsequently, the silica particles are removed, and thus, the reinforced composite membrane is converted into a reinforced microsieve of 350 nm ± 50 nm thickness bearing uniform through pores of 465 nm ± 50 nm diameter. This reinforced microsieve is mounted into a filtration unit and used to filter model dispersions: its permeance for water at low Reynolds numbers is in accordance with established theories on the permeance of microsieves and significantly above the permeance of conventional filtration media; it retains particles exceeding the pore size, while letting particles smaller than the pore size pass.

3.
J Womens Health (Larchmt) ; 25(9): 912-9, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27532245

RESUMEN

OBJECTIVES: The incidence of cardiovascular morbidity and mortality in premenopausal women is comparatively low, but increases sharply after menopause. The principal aim of this study was to determine whether women with ascending aortic disease (AAD) have a different reproductive history from that of an age-matched control group. METHODS: In this retrospective study, women who had undergone ascending aortic aneurysm (AscAA) repair between 2000 and 2010 were asked to complete a questionnaire concerning risk factors and reproductive history. Data from 142 women with AAD were evaluated, and a subgroup (n = 64) with AscAA ≥5 cm was analyzed and compared to an age-matched random control group without known aortic diseases. RESULTS: Almost all women were menopausal at the time of the questionnaire (98.4% vs. 90.6%, AscAA ≥5 cm subcohort vs. control, p = 0.12) and all subjects presented with a comparable age of menarche (13.7 ± 2.6 years vs. 14.2 ± 1.8 years, AscAA ≥5 cm subcohort vs. control, log-rank 0.04, p = 0.84). However, mean menopausal age was significantly lower in the case subcohort than in controls (48.1 ± 4.8 years vs. 50.6 ± 5.8 years, AscAA ≥5 cm subcohort vs. control, log-rank 8.35, p = 0.004), and reproductive life span was correspondingly shorter (34.2 ± 5.2 years vs. 36.2 ± 5.7 years, p = 0.04). Furthermore, hypertension was more prevalent in women with AscAA ≥5 cm compared to controls (89.1% vs. 61.9%, AscAA ≥5 cm subcohort vs. control, p < 0.001). CONCLUSION: Women who experience menopause at an earlier age than the regional mean could profit from screening for cardiovascular disease in general and particularly for AAD. Screening would enable early aneurysm detection and could, therefore, reduce morbidity and mortality.


Asunto(s)
Enfermedades de la Aorta/fisiopatología , Menopausia , Historia Reproductiva , Factores de Edad , Anciano , Estudios de Casos y Controles , Femenino , Alemania , Humanos , Menarquia , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Encuestas y Cuestionarios
4.
Transplantation ; 95(4): 629-34, 2013 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-23423270

RESUMEN

BACKGROUND: Long-term results of prospective randomized trials comparing triple immunosuppressive strategies combining tacrolimus (TAC) or cyclosporine A (CsA) with mycophenolate mofetil (MMF) and steroids after heart transplantation (HTX) are rarely published. Therefore, we collected long-term follow-up data of an intervention cohort 10 years after randomization. METHODS: Ten-year follow-up data of 60 patients included in a prospective, randomized trial between 1998 and 2000 were analyzed as intention-to-treat (TAC-MMF n=30; CsA-MMF n=30). Baseline characteristics were well balanced. Cardiac allograft vasculopathy (CAV) was graduated in accordance with the new ISHLT classification. RESULTS: Survival at 1, 5, and 10 years was 96.7%, 80.0%, and 66.7% for TAC-MMF and 90.0%, 83.3%, and 80.0% for CsA-MMF (P=ns). Freedom from acute rejection (AR) was significantly higher in TAC-MMF versus CsA-MMF (65.5% vs. 21.7%, log-rank 8.3, P=0.004). Freedom from ISHLT≥CAV1 after 5 and 10 years was in TAC-MMF 64.0% and 45.8%, and in CsA-MMF 36.0% (log-rank 3.0, P=0.085) and 8.0% (log-rank 9.0, P=0.003). No difference in long-term results for freedom from coronary angioplasty or stenting, renal dysfunction, diabetes mellitus, CMV infection, or malignancy was detected. CONCLUSION: Cross-over effects because of treatment switch may result in impairment of significance between the groups. The long-term analysis resulted in a significant difference in manifestation of CAV between the groups after 10 years. Less rejection in the TAC-group might have contributed to the lower incidence of CAV. Superior freedom from AR and CAV in the TAC-MMF group did not result in better long-term survival.


Asunto(s)
Ciclosporina/uso terapéutico , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Corazón/inmunología , Inmunosupresores/uso terapéutico , Ácido Micofenólico/análogos & derivados , Tacrolimus/uso terapéutico , Adulto , Distribución de Chi-Cuadrado , Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/terapia , Ciclosporina/efectos adversos , Ciclosporina/sangre , Monitoreo de Drogas , Quimioterapia Combinada , Femenino , Alemania , Rechazo de Injerto/inmunología , Rechazo de Injerto/mortalidad , Trasplante de Corazón/efectos adversos , Trasplante de Corazón/mortalidad , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/sangre , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Ácido Micofenólico/efectos adversos , Ácido Micofenólico/sangre , Ácido Micofenólico/uso terapéutico , Estudios Prospectivos , Factores de Riesgo , Tacrolimus/efectos adversos , Tacrolimus/sangre , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
5.
Artif Organs ; 36(3): E48-52, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22352368

RESUMEN

The Berlin Heart EXCOR ventricular assist device provides pulsatile ventricular assistance. It can be used for univentricular or biventricular support. However, pre-, intra-, and postoperative complications (e.g., bleeding, anastomotic insufficiency) are frequent. We present herein a detailed description of our modified implantation technique in order to facilitate further clinical use of the system.


Asunto(s)
Ventrículos Cardíacos/cirugía , Corazón Auxiliar , Adulto , Aorta/cirugía , Cateterismo , Atrios Cardíacos/cirugía , Corazón Auxiliar/efectos adversos , Humanos , Arteria Pulmonar/cirugía
6.
Exp Clin Transplant ; 9(4): 279-83, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21819376

RESUMEN

Invasive pulmonary aspergillosis is a severe complication after solid organ transplant, with a high mortality rate. We present a 45-year-old male heart transplant recipient who developed fever, progressive worsening of dyspnea, and productive cough without response to antibiotics. Diagnosis of invasive pulmonary aspergillosis was made based on clinical, laboratory, and radiographic findings. The patient was treated successfully with combined antifungal therapy (voriconazole and micafungin). This case report highlights the importance of a high degree of clinical suspicion to allow curative treatment of invasive aspergillosis and the efficiency of new antifungal drugs.


Asunto(s)
Antifúngicos/uso terapéutico , Equinocandinas/uso terapéutico , Trasplante de Corazón/efectos adversos , Aspergilosis Pulmonar Invasiva/tratamiento farmacológico , Lipopéptidos/uso terapéutico , Pirimidinas/uso terapéutico , Triazoles/uso terapéutico , Quimioterapia Combinada , Humanos , Aspergilosis Pulmonar Invasiva/diagnóstico por imagen , Aspergilosis Pulmonar Invasiva/microbiología , Masculino , Micafungina , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Voriconazol
7.
Heart Surg Forum ; 14(4): E258-60, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21859648

RESUMEN

In an aging population, numerous patients who underwent previous coronary artery bypass grafting (CABG) are presenting with end-stage ischemic cardiomyopathy. Although redo CABG and cardiological interventions are possible treatment options, orthotopic heart transplantation remains an ultimate option for these patients. However, there is high morbidity and mortality on the waiting list, and mechanical circulatory support is a life-saving concept [Hetzer 2006; Taylor 2009].We developed a simplified and safe technique for implantation of a biventricular assist device as a redo in complex patients after previous CABG and end-stage heart failure.


Asunto(s)
Puente de Arteria Coronaria , Insuficiencia Cardíaca/cirugía , Ventrículos Cardíacos/cirugía , Corazón Auxiliar , Isquemia Miocárdica/cirugía , Implantación de Prótesis/normas , Función Ventricular/fisiología , Anciano , Cateterismo Cardíaco , Estudios de Seguimiento , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/fisiopatología , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/fisiopatología , Implantación de Prótesis/métodos
8.
Int J Artif Organs ; 34(4): 365-73, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21534247

RESUMEN

BACKGROUND: For short-term ventricular and pulmonary support the extracorporeal membrane oxygenation (ECMO) system using the Bio-Medicus centrifugal pump (Medtronic®, Minneapolis, MN, USA) was applied in 108 patients with cardiac low-output. METHODS: From December 1996 to July 2006 the ECMO was implanted in 108 patients (73 adult, mean age: 49.3±18.0 yrs and 35 children, mean age: 1.3 ± 2.7 yrs) with mostly postcardiotomy cardiac low output. The surgical procedures included congenital heart surgery (n=35), heart transplantation (HTx) (n=21), coronary artery bypass operation (CABG) and/or valvular operation (n=33), other operations (n=6) and 13 patients with ECMO support for bridge to recovery. RESULTS: The mean supporting time was 5.1±5.6 days. Overall, 30-day-survival was 40.2%. Best survival rates were seen after congenital heart surgery (24/35, 65.7%) and after HTx (9/21, 42.9%); the worst rates were in the group of CABG and/or valvular operations (5/33, 15.2%), only ECMO support (3/13, 23.1%) and other operations (1/6, 16.7%). Fifty-four patients died while supported by ECMO, 15 were weaned from ECMO but died in hospital, 39 patients were weaned and survived. Causes of death were multi-organ failure (40.6%), bleeding (23.2%), persistent cardiac low output (21.7%), thrombembolic events (8.7%), and graft failure (5.8%). Markers for adverse outcome were identified as older age, high body weight, increased AST/GOT levels, and lower thrombocyte count in adults; and as higher levels of serum creatinine in pediatric patients. CONCLUSIONS: ECMO support showed best results in pediatric patients after congenital heart surgery and in patients after HTx in contrast to multimorbid, older patients with often irreversible myocardial damage.


Asunto(s)
Gasto Cardíaco Bajo/terapia , Gasto Cardíaco , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Oxigenación por Membrana Extracorpórea , Adulto , Materiales Biocompatibles , Gasto Cardíaco Bajo/etiología , Gasto Cardíaco Bajo/mortalidad , Gasto Cardíaco Bajo/fisiopatología , Procedimientos Quirúrgicos Cardíacos/mortalidad , Preescolar , Oxigenación por Membrana Extracorpórea/efectos adversos , Oxigenación por Membrana Extracorpórea/instrumentación , Oxigenación por Membrana Extracorpórea/mortalidad , Femenino , Alemania , Corazón Auxiliar , Humanos , Lactante , Recién Nacido , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Medición de Riesgo , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
9.
J Heart Lung Transplant ; 30(8): 912-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21489819

RESUMEN

BACKGROUND: The purpose of this study was to examine the effect of an inpatient rehabilitation program on health-related quality of life (HRQOL) and exercise capacity (EC) in long-term (>1 year after lung transplantation) survivors (LTSs) in comparison to a control group (CG). METHODS: Sixty LTSs, 4.5 ± 3.2 years after lung transplantation (LTx), were randomly assigned to two equally sized groups that were stratified for gender and underlying disease. Thirty LTSs (age 49 ± 13 years, 13 male and 17 females, 19 double LTxs, 7 BOS Stage ≥ 1) attended an inpatient rehabilitation program (intervention group, IG) for 23 ± 5 days. The CG (age 50 ± 12 years, 13 males and 17 females, 20 double LTxs, 2 BOS Stage ≥ 1) received medical standard therapy (physiotherapy). Patients were evaluated by cardiopulmonary exercise testing, 6-minute walk test (6MWT), SF-36, SGRQ and the Quality of Life Profile for Chronic Diseases questionnaire before and after (18 ± 3 days) the program. RESULTS: The groups were statistically indistinguishable in terms of clinical data. Each treatment group significantly improved their sub-maximal EC (6MWT: IG, 493 ± 90 m vs 538 ± 90 m, p < 0.001; CG, 490 ± 88 m vs 514 ± 89 m, p < 0.001) and maximal EC (VO(2peak): IG, 17.0 vs 18.5 ml/min/kg, p = 0.039; CG, 18.0 vs 19.5 ml/min/kg, p = 0.005), without reaching statistical significance between the groups. In both study groups, patients HRQOL tended to improve. Significant correlations were found between EC parameters and HRQOL scales. CONCLUSIONS: Our data suggest that structured physical training may improve exercise tolerance in LTS. Our study results did not demonstrate a significant benefit of an inpatient over an outpatient exercise program.


Asunto(s)
Tolerancia al Ejercicio/fisiología , Pacientes Internos , Trasplante de Pulmón/rehabilitación , Modalidades de Fisioterapia , Calidad de Vida , Adulto , Femenino , Humanos , Trasplante de Pulmón/fisiología , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Estudios Prospectivos , Pruebas de Función Respiratoria , Encuestas y Cuestionarios , Resultado del Tratamiento , Caminata/fisiología
10.
Transpl Int ; 23(9): 887-96, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20230541

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a frequent indication for lung transplantation (LTX) with pulmonary hypertension (PH) negatively affecting outcome. The optimal procedure type remains a debated topic. The aim of this study was to evaluate the impact of pretransplant PH in IPF patients. Single LTX (SLTX, n = 46) was the standard procedure type. Double LTX (DLTX, n = 30) was only performed in cases of relevant PH or additional suppurative lung disease. There was no significant difference for pretransplant clinical parameters. Preoperative mean pulmonary arterial pressure was significantly higher in DLTX recipients (22.7 +/- 0.8 mmHg vs. 35.9 +/- 1.8 mmHg, P < 0.001). After transplantation, 6-min-walk distance and BEST-FEV(1) were significantly higher for DLTX patients (6-MWD: 410 +/- 25 m vs. 498 +/- 23 m, P = 0.02; BEST-FEV(1): 71.2 +/- 3.0 (% pred) vs. 86.2 +/- 4.2 (% pred), P = 0.004). Double LTX recipients demonstrated a significantly better 1-year-, overall- and Bronchiolitis obliterans Syndrome (BOS)-free survival (P < 0.05). Cox regression analysis confirmed SLTX to be a significant predictor for death and BOS. Single LTX offers acceptable survival rates for IPF patients. Double LTX provides a significant benefit in selected recipients. Our data warrant further trials of SLTX versus DLTX stratifying for potential confounders including PH.


Asunto(s)
Supervivencia de Injerto/fisiología , Fibrosis Pulmonar Idiopática/cirugía , Trasplante de Pulmón/métodos , Supervivencia sin Enfermedad , Prueba de Esfuerzo , Femenino , Estudios de Seguimiento , Volumen Espiratorio Forzado/fisiología , Alemania/epidemiología , Humanos , Fibrosis Pulmonar Idiopática/mortalidad , Fibrosis Pulmonar Idiopática/fisiopatología , Trasplante de Pulmón/mortalidad , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
11.
J Heart Lung Transplant ; 28(5): 468-74, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19416775

RESUMEN

BACKGROUND: Bronchoalveolar lavage (BAL) neutrophilia may identify patients prone to develop bronchiolitis obliterans syndrome (BOS) after lung transplantation (LTx). This study assessed the predictive value of BAL neutrophilia in stable recipients. METHODS: Evaluated were 63 consecutive recipients 3 to 12 months after LTx demonstrating no acute rejection (AR) and lymphocytic bronchitis (LB; B < or = 1 without infection; BOS, 0). Recipients were subdivided into never-BOS (follow-up > or = 12 months) and ever-BOS groups (i.e., BOS development > or = 1 after bronchoscopy). RESULTS: The groups were statistically indistinguishable for demographic data and preceding AR and LB episodes. Onset of BOS was at a median of 232 days (range, 87-962) after bronchoscopy. The ever-BOS group (16 patients) demonstrated a significantly higher percentage of neutrophils compared with the never-BOS group (47 patients) at the time of bronchoscopy (33.6% +/- 2.1% vs 9.9% +/- 1.1%, p < 0.05). By Cox regression analysis, a BAL neutrophil percentage of > or = 20% remained a significant predictor for BOS > or = 1 (hazard ratio, 3.57; 95% confidence interval, 1.71-8.40, p < 0.05) distinct from known potential BOS predictor variables. The positive and negative predictive value of BAL neutrophilia of > or = 20% for future BOS was 0.72 and 0.93, respectively (p < 0.05). CONCLUSION: BAL neutrophilia in stable recipients is of predictive value to identify recipients at risk for BOS. These data warrant prospective confirmation and further studies to evaluate the benefit of preemptive therapy for potential BOS patients.


Asunto(s)
Bronquiolitis Obliterante/diagnóstico , Bronquiolitis Obliterante/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Recuento de Leucocitos , Trasplante de Pulmón/inmunología , Neutrófilos/inmunología , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/inmunología , Adulto , Biopsia , Bronquios/patología , Bronquiolitis Obliterante/patología , Broncoscopía , Estudios de Cohortes , Femenino , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Humanos , Interleucina-8/metabolismo , Trasplante de Pulmón/patología , Masculino , Persona de Mediana Edad , Neutrófilos/patología , Complicaciones Posoperatorias/patología , Valor Predictivo de las Pruebas , Pronóstico , Análisis de Regresión , Estudios Retrospectivos , Factores de Riesgo , Inhibidor Secretorio de Peptidasas Leucocitarias/metabolismo
12.
Exp Clin Transplant ; 7(4): 261-3, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20353379

RESUMEN

Cardiac allograft vasculopathy is a severe complication after heart transplant, and is the major cause of death in patients surviving 1 year after transplant. We present a 59-year-old patient undergoing off-pump, coronary artery bypass surgery, 8 years after heart transplant. Owing to toxic liver disease, the lipid lowering therapy with statins had to be stopped 6 years after transplant, and coronary artery disease developed rapidly within 2 years. Off-pump, coronary bypass surgery was performed using a new, multisuction cardiac positioner; a disposable stabilizer; and a proximal seal system to avoid clamping of the aorta. The patient received 3 bypass grafts: the left internal thoracic artery; to the left anterior descending coronary artery; 1 saphenous vein graft to the marginal branch of the circumflex artery; and 1 saphenous vein graft to the right coronary artery. His postoperative course was uneventful.


Asunto(s)
Puente de Arteria Coronaria Off-Pump , Enfermedad de la Arteria Coronaria/cirugía , Trasplante de Corazón/efectos adversos , Puente de Arteria Coronaria Off-Pump/instrumentación , Enfermedad de la Arteria Coronaria/etiología , Humanos , Masculino , Persona de Mediana Edad , Trasplante Homólogo , Resultado del Tratamiento
13.
Exp Clin Transplant ; 6(3): 229-35, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18954302

RESUMEN

OBJECTIVES: The clinical significance of anti-HLA-alloantibodies remains controversial. Recent studies have linked development of donor-specific HLA-antibodies to chronic allograft rejection and graft loss after heart, kidney, and lung transplants. We investigated the clinical impact of donor-specific humoral alloreactivity during the follow-up of heart transplant recipients. PATIENTS AND METHODS: The sera of 213 heart transplant recipients were screened by enzyme-linked immunosorbent assay for HLA-antibody production. The antigen specificity of the detected HLA class I and class II antibodies was identified using a Luminex assay. Outcome variables were survival, cardiac allograft vasculopathy, and cellular rejection. RESULTS: The cumulative incidence of alloantibody formation was 23/213 patients (10.8%). The majority of detected alloantibodies were donor-specific for HLA class II. Mean follow-up at antibody measurements was 7 -/+ 4.9 years. Freedom from vasculopathy at 5 and 10 years was 77.9% and 26% in donor-specific HLA-antibody-positive patients compared with 84.6% and 65.2% in antibody-negative controls (P = .025). Freedom from treated, biopsy-proven rejection was 44.4% for donor-specific HLA-antibody-positive patients compared with 70.2% in the controls (P = .06). Multivariate analyses identified donor-specific HLA antibody positivity as an independent risk factor for vasculopathy. CONCLUSIONS: Our results demonstrate a strong correlation between the development of donor-specific HLA antibodies and adverse outcomes after heart transplant. Detection of donor-specific HLA antibodies might identify high-risk patients and offer an opportunity for early clinical intervention and modification of immunosuppression.


Asunto(s)
Antígenos HLA/inmunología , Trasplante de Corazón/inmunología , Isoanticuerpos/sangre , Adulto , Formación de Anticuerpos , Cardiomiopatía Dilatada/cirugía , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Rechazo de Injerto/epidemiología , Rechazo de Injerto/inmunología , Trasplante de Corazón/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Análisis de Supervivencia , Sobrevivientes , Factores de Tiempo , Donantes de Tejidos
14.
Ther Drug Monit ; 30(4): 419-27, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18641552

RESUMEN

Pharmacokinetics of mycophenolate mofetil (MMF) show large interindividual variability. Concentration-controlled dosing of MMF based on routine therapeutic drug monitoring, which requires area under the concentration-time curve (mycophenolic acid [MPA]-AUC0-12h) determinations, is uncommon. Dose adjustments are based on predose concentrations (C0h) or side effects. The aim of this study was to compare C0h with postdose concentrations (C0.5h-C12h) and to develop practical methods for estimation of MPA-AUCs on the basis of a limited sampling strategy (LSS) in heart transplant recipients under MMF and tacrolimus maintenance immunosuppression. Full MPA-AUC0-12h profiles were generated by high-performance liquid chromatography in 28 patients. Statistical analysis for MPA-AUC0-12h was performed by a case resampling bootstrap method. Bland and Altmann analysis was performed to test agreement between "predicted AUC" and "measured AUC." C1h provided the highest coefficient of determination (r2 = 0.57) among the concentrations determined during the 12-hour interval, which were correlated with AUC. All other MPA levels were better surrogates of the MPA-AUC0-12h when compared with C0h (r2 = 0.14). The best estimation of MPA-AUC0-12h was achieved with four sampling points with the algorithm AUC = 1.25*C1h + 5.29*C4h + 2.90*C8h + 3.61*C10h (r2 = 0.95). Since LSS with four time points appeared unpractical, the authors prefer models with three or two points. To optimize practicability, LSS with sample points within the first 2 hours were evaluated resulting in the algorithms: AUC = 1.09*C0.5h + 1.19*C1h + 3.60*C2h (r2 = 0.84) and AUC = 1.65*C0.5h + 4.74*C2h (r2 = 0.75) for three and two sample points, respectively. The results provide strong evidence for the use of either LSS or the use of time points other than C0h for therapeutic drug monitoring of MMF. Using the algorithms for the estimation of MPA-AUC0-12h based on LSS within the first 2 hours after MMF dosing may help to optimize treatment with MMF by individualization of dosing.


Asunto(s)
Algoritmos , Monitoreo de Drogas/estadística & datos numéricos , Trasplante de Corazón/inmunología , Inmunosupresores/uso terapéutico , Ácido Micofenólico/análogos & derivados , Adulto , Anciano , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/farmacocinética , Masculino , Persona de Mediana Edad , Ácido Micofenólico/administración & dosificación , Ácido Micofenólico/farmacocinética , Ácido Micofenólico/uso terapéutico , Valor Predictivo de las Pruebas , Tacrolimus/farmacocinética , Tacrolimus/uso terapéutico , Adulto Joven
15.
Eur J Echocardiogr ; 9(4): 494-500, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17923438

RESUMEN

AIM: To evaluate the additional benefit of visual and quantitative perfusion measurements compared with conventional real-time myocardial contrast echocardiography (MCE) in the detection of CAV. METHODS AND RESULTS: Thirty patients (26 males, age 58 +/- 9.6 years) underwent dobutamine stress echocardiography (DSE) and myocardial perfusion imaging (MPI) as well as coronary angiography (CA) with intravascular ultrasound (IVUS). Ultrasound images were analysed off-line, evaluating (1) wall motion and thickening at high mechanical index ('conventional evaluation'), (2) the MCE loops stored during continuous infusion of contrast agent with regard to visual changes (stress vs. rest, 'visual grading'), and (3) the replenishment curves of the contrast agent at low mechanical index after bubble destruction ('quantitative grading'). CA/IVUS plus MPI showed ischaemia in seven and myocardial scars in nine patients. Sensitivity, specificity, NPV, PPV and accuracy for the detection of ischaemia representing functionally relevant CAV were, respectively, 0.71, 0.83, 0.90, 0.55 and 0.80 for the conventional evaluation alone, 0.71, 0.91, 0.91, 0.71 and 0.87 for additional visual grading and 0.86, 0.91, 0.95, 0.75 and 0.90 for additional quantitative grading. CONCLUSION: Real-time MCE including visual and quantitative analysis is feasible for screening patients after HTX and is highly accurate in the diagnosis of haemodynamically relevant CAV.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Ecocardiografía , Trasplante de Corazón/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único , Trasplante Homólogo , Anciano , Circulación Coronaria , Vasos Coronarios/diagnóstico por imagen , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos , Tecnecio Tc 99m Sestamibi
16.
J Heart Lung Transplant ; 26(6): 598-603, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17543783

RESUMEN

Heart transplant recipients treated with long-term calcineurin inhibitors (CNIs) experience significant nephrotoxicity and transplant vasculopathy. Signal proliferation inhibitors might prevent the development of transplant vasculopathy. In an open, prospective pilot study, 33 primary heart transplant recipients received tacrolimus (Tac) and sirolimus (rapamycin, Rapa) with steroids. To reduce both nephrotoxicity and transplant vasculopathy at the same time, both Tac and Rapa exposure was kept low (6 to 8 ng/ml). Steroids were withdrawn successfully from all patients within 6 months. Just one acute rejection occurred at 54 days post-transplant, resulting in 0.03 acute rejection episode per patient at 1-year (primary end-point) and 2-year follow-up. Transplant vasculopathy assessed by angiogram was absent at 2 years. Graft and patient survival were 100% at 1 and 2 years. Accordingly, the survival estimate for freedom from first acute rejection, transplant vasculopathy, graft loss or death was 0.97 at 1 and 2 years. The regimen was well tolerated with only 3 patients requiring a change of study medication. Mean serum creatinine increased during the first year but returned to baseline at 2 years.


Asunto(s)
Trasplante de Corazón/inmunología , Inmunosupresores/uso terapéutico , Sirolimus/uso terapéutico , Tacrolimus/uso terapéutico , Corticoesteroides/administración & dosificación , Adulto , Esquema de Medicación , Femenino , Estudios de Seguimiento , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/epidemiología , Insuficiencia Cardíaca/cirugía , Humanos , Infecciones , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos , Factores de Tiempo
17.
J Nucl Med ; 47(9): 1413-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16954547

RESUMEN

UNLABELLED: The transplanted heart is initially denervated but undergoes subsequent sympathetic reinnervation. It thus provides a unique model for studying regeneration as a specific component of autonomic nerve biology. The aim of this study was to determine the effect of diabetes mellitus on the regenerational capacity of sympathetic neurons using molecule-targeted PET. METHODS: Twenty-two nonrejecting, otherwise healthy cardiac transplant recipients underwent PET with the (11)C-labeled physiologic neurotransmitter epinephrine at 4.0 +/- 3.3 y after surgery. Sympathetic reinnervation was defined as regional restoration of epinephrine retention to values within normal limits. RESULTS: Reinnervation was observed in 8 of 12 patients with no evidence of diabetes and in 6 of 10 patients with a long-term history of diabetes mellitus. The regional extent of reinnervation (4.7% +/- 5.3% of left ventricle vs. 19.1% +/- 20.6% for nondiabetic recipients, P = 0.04) and the regeneration rate (0.8% +/- 1.0% of left ventricle per year vs. 8.0% +/- 10.1% for nondiabetic recipients, P = 0.04) were significantly reduced in diabetic subjects. In a multivariate model, diabetes mellitus was an independent determinant of allograft reinnervation. Finally, the reappearance of innervation was found to correlate with an improved chronotropic and inotropic response to stress in a standardized, symptom-limited exercise test including radionuclide angiography. CONCLUSION: The regenerational capacity of the sympathetic nervous system of the heart is reduced, but not abolished, by diabetes mellitus. This study on cardiac transplant recipients further supports a general link between impaired glucose handling and cardiac autonomic nerve function.


Asunto(s)
Diabetes Mellitus/fisiopatología , Trasplante de Corazón/fisiología , Corazón/inervación , Corazón/fisiopatología , Regeneración Nerviosa/fisiología , Sistema Nervioso Simpático/fisiopatología , Catecolaminas/metabolismo , Diabetes Mellitus/diagnóstico por imagen , Femenino , Corazón/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Miocardio/metabolismo , Cintigrafía , Recuperación de la Función/fisiología
18.
Transplantation ; 81(3): 355-60, 2006 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-16477220

RESUMEN

BACKGROUND: Bronchiolitis obliterans syndrome (BOS) is the major problem after lung and heart-lung transplantation (LTx/HLTx). Sirolimus (Sir) and Mycophenolate (MMF) showed a promising efficacy in the treatment of BOS in animal models. The first clinical experience in converting LTx/HLTx-recipients with BOS from calcineurin inhibitor-(CNI)-based immunosuppression to a Sir-MMF based immunosuppression is reported herein. METHODS: Six LTx- and five HLTx-recipients (eight men; 0.9 to 8 years after transplantation) with CNI-based immunosuppression (plus MMF) in whom BOS was diagnosed were included in the study. Mean patient age was 37+/-13 years (range 17-62 years). Sir was started with 6 mg and continued adjusted to according target trough levels (8-14 ng/ml). Subsequently, the CNIs were tapered down and finally stopped. Follow up included self determined pulmonary function tests, microbiological screening, chest radiographs, and laboratory studies RESULTS: Two acute rejection episodes occurred during the study period. The incidence of infection was 2.2+/-1.3 infections/patient-year after conversion. Mean FEV1 decreased after a mean follow up of 14.8+/-1.4 months: from 2.1+/-0.7 l prior conversion to 1.3+/-0.6l after conversion (P=0.03). However, graft function remained stable in three patients and progression of BOS slowed down in three patients. Overall, 2 of 10 patients died due to ongoing BOS while awaiting retransplantation CONCLUSIONS: After BOS was diagnosed, conversion to MMF and Sir stabilized graft function only in some of the converted patients. Therefore, earlier administration of Sir-based immunosuppression might be a more promising approach. Whether conversion to CNI-free immunosuppression can actually ameliorate the extent or progression of BOS has to be investigated in randomized trials.


Asunto(s)
Bronquiolitis Obliterante/tratamiento farmacológico , Rechazo de Injerto/prevención & control , Inmunosupresores/uso terapéutico , Trasplante de Pulmón , Ácido Micofenólico/análogos & derivados , Sirolimus/uso terapéutico , Adolescente , Adulto , Inhibidores de la Calcineurina , Progresión de la Enfermedad , Femenino , Trasplante de Corazón-Pulmón , Humanos , Terapia de Inmunosupresión/métodos , Inmunosupresores/efectos adversos , Riñón/efectos de los fármacos , Masculino , Persona de Mediana Edad , Ácido Micofenólico/efectos adversos , Ácido Micofenólico/uso terapéutico , Sirolimus/efectos adversos , Síndrome
19.
Eur Heart J ; 25(19): 1726-33, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15451151

RESUMEN

AIMS: To evaluate effects of beta-adrenergic receptor blockade on allograft performance, and to correlate these effects with sympathetic reinnervation. METHODS AND RESULTS: Myocardial catecholamine storage capacity was determined in 12 non-rejecting transplant recipients using PET and C-11 adrenaline (epinephrine). Haemodynamics and left ventricular function were measured using radionuclide angiography at rest and during symptom-limited exercise before and after non-selective beta-blockade (propranolol iv). Exercise time and stress-induced increases of heart rate and LVEF before beta-blockade were significantly higher in reinnervated compared to denervated recipients. While resting LVEF remained unchanged, heart rate and blood pressure were generally reduced by beta-blockade, which was well tolerated by all patients. Exercise time and increases of heart rate and LVEF were more attenuated in reinnervated recipients. Differences of chronotropic and inotropic response to exercise between groups were no longer present following beta-blockade. Correlations between myocardial adrenaline retention, peak heart rate and increase of global, as well as regional ejection fraction during exercise were observed before, but not during beta-blockade. CONCLUSION: Acute, non-selective beta-blockade is well tolerated by transplant recipients, but significantly attenuates beneficial functional effects of sympathetic reinnervation on exercise performance. The data suggest that reappearance of sympathetic nerve terminals is associated with reestablishment of intact pre-/postsynaptic interaction.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Trasplante de Corazón , Regeneración Nerviosa/fisiología , Propranolol/uso terapéutico , Sistema Nervioso Simpático/fisiología , Ejercicio Físico/fisiología , Tolerancia al Ejercicio , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Trasplante Homólogo , Función Ventricular Izquierda/fisiología
20.
J Heart Lung Transplant ; 23(5): 632-8, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15135383

RESUMEN

A prospective, pilot trial was started to evaluate the effect of a sirolimus-based immunosuppressive regimen on acute and chronic rejection in de novo lung transplant patients. Primary lung transplant (LTx) recipients received a sirolimus- and tacrolimus-based immunosuppressive therapy immediately after transplantation. Both immunosuppressants were administered with trough level adjusted, while steroid administration was minimized. Four patients were enrolled (2 single-lung transplants, 1 double-lung transplant, 1 heart-lung transplant) in the study. Mean ischemia time was 387 +/- 92 minutes. Acute rejection (at least Grade A1 ISHLT) was detected in 1 patient. Incidence of infection was 0.6 infection per 100 patient-days (3 Aspergillus infections). Until hospital discharge mean sirolimus trough level was 6.2 +/- 1.2 ng/ml. Depending upon mean sirolimus trough levels of each patient, severe wound-healing complications were seen in 3 patients, resulting in bronchial airway dehiscence in 2 patients with lethal outcome in 1 patient. As a result of these complications, we revised the study design after inclusion of only 4 patients: Sirolimus administration is now started after completion of bronchial wound-healing. Sirolimus-based immunosuppressive therapy administered immediately after lung transplantation seems to be associated with severe wound-healing complications of the bronchial anastomosis.


Asunto(s)
Enfermedades Bronquiales/etiología , Terapia de Inmunosupresión/efectos adversos , Terapia de Inmunosupresión/métodos , Inmunosupresores/administración & dosificación , Trasplante de Pulmón , Sirolimus/administración & dosificación , Corticoesteroides/administración & dosificación , Adulto , Rechazo de Injerto/prevención & control , Trasplante de Corazón-Pulmón , Humanos , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Complicaciones Posoperatorias , Estudios Prospectivos , Sirolimus/efectos adversos , Tacrolimus/administración & dosificación , Cicatrización de Heridas/efectos de los fármacos
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