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2.
Langmuir ; 35(6): 2196-2208, 2019 Feb 12.
Article in English | MEDLINE | ID: mdl-30590922

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-27532245

ABSTRACT

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.


Subject(s)
Aortic Diseases/physiopathology , Menopause , Reproductive History , Age Factors , Aged , Case-Control Studies , Female , Germany , Humans , Menarche , Middle Aged , Retrospective Studies , Risk Factors , Surveys and Questionnaires
4.
Transplantation ; 95(4): 629-34, 2013 Feb 27.
Article in English | MEDLINE | ID: mdl-23423270

ABSTRACT

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.


Subject(s)
Cyclosporine/therapeutic use , Graft Rejection/prevention & control , Graft Survival/drug effects , Heart Transplantation/immunology , Immunosuppressive Agents/therapeutic use , Mycophenolic Acid/analogs & derivatives , Tacrolimus/therapeutic use , Adult , Chi-Square Distribution , Coronary Artery Disease/etiology , Coronary Artery Disease/therapy , Cyclosporine/adverse effects , Cyclosporine/blood , Drug Monitoring , Drug Therapy, Combination , Female , Germany , Graft Rejection/immunology , Graft Rejection/mortality , Heart Transplantation/adverse effects , Heart Transplantation/mortality , Humans , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/blood , Kaplan-Meier Estimate , Logistic Models , Male , Middle Aged , Mycophenolic Acid/adverse effects , Mycophenolic Acid/blood , Mycophenolic Acid/therapeutic use , Prospective Studies , Risk Factors , Tacrolimus/adverse effects , Tacrolimus/blood , Time Factors , Treatment Outcome , Young Adult
5.
Artif Organs ; 36(3): E48-52, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22352368

ABSTRACT

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.


Subject(s)
Heart Ventricles/surgery , Heart-Assist Devices , Adult , Aorta/surgery , Catheterization , Heart Atria/surgery , Heart-Assist Devices/adverse effects , Humans , Pulmonary Artery/surgery
6.
Exp Clin Transplant ; 9(4): 279-83, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21819376

ABSTRACT

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.


Subject(s)
Antifungal Agents/therapeutic use , Echinocandins/therapeutic use , Heart Transplantation/adverse effects , Invasive Pulmonary Aspergillosis/drug therapy , Lipopeptides/therapeutic use , Pyrimidines/therapeutic use , Triazoles/therapeutic use , Drug Therapy, Combination , Humans , Invasive Pulmonary Aspergillosis/diagnostic imaging , Invasive Pulmonary Aspergillosis/microbiology , Male , Micafungin , Middle Aged , Tomography, X-Ray Computed , Treatment Outcome , Voriconazole
7.
Heart Surg Forum ; 14(4): E258-60, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21859648

ABSTRACT

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.


Subject(s)
Coronary Artery Bypass , Heart Failure/surgery , Heart Ventricles/surgery , Heart-Assist Devices , Myocardial Ischemia/surgery , Prosthesis Implantation/standards , Ventricular Function/physiology , Aged , Cardiac Catheterization , Follow-Up Studies , Heart Failure/complications , Heart Failure/physiopathology , Heart Ventricles/physiopathology , Humans , Male , Middle Aged , Myocardial Ischemia/complications , Myocardial Ischemia/physiopathology , Prosthesis Implantation/methods
8.
Int J Artif Organs ; 34(4): 365-73, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21534247

ABSTRACT

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.


Subject(s)
Cardiac Output, Low/therapy , Cardiac Output , Cardiac Surgical Procedures/adverse effects , Extracorporeal Membrane Oxygenation , Adult , Biocompatible Materials , Cardiac Output, Low/etiology , Cardiac Output, Low/mortality , Cardiac Output, Low/physiopathology , Cardiac Surgical Procedures/mortality , Child, Preschool , Extracorporeal Membrane Oxygenation/adverse effects , Extracorporeal Membrane Oxygenation/instrumentation , Extracorporeal Membrane Oxygenation/mortality , Female , Germany , Heart-Assist Devices , Humans , Infant , Infant, Newborn , Kaplan-Meier Estimate , Male , Middle Aged , Prosthesis Design , Risk Assessment , Risk Factors , Survival Rate , Time Factors , Treatment Outcome
9.
J Heart Lung Transplant ; 30(8): 912-9, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21489819

ABSTRACT

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.


Subject(s)
Exercise Tolerance/physiology , Inpatients , Lung Transplantation/rehabilitation , Physical Therapy Modalities , Quality of Life , Adult , Female , Humans , Lung Transplantation/physiology , Male , Middle Aged , Outpatients , Prospective Studies , Respiratory Function Tests , Surveys and Questionnaires , Treatment Outcome , Walking/physiology
10.
Transpl Int ; 23(9): 887-96, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20230541

ABSTRACT

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.


Subject(s)
Graft Survival/physiology , Idiopathic Pulmonary Fibrosis/surgery , Lung Transplantation/methods , Disease-Free Survival , Exercise Test , Female , Follow-Up Studies , Forced Expiratory Volume/physiology , Germany/epidemiology , Humans , Idiopathic Pulmonary Fibrosis/mortality , Idiopathic Pulmonary Fibrosis/physiopathology , Lung Transplantation/mortality , Male , Middle Aged , Retrospective Studies , Time Factors , Treatment Outcome
11.
J Heart Lung Transplant ; 28(5): 468-74, 2009 May.
Article in English | MEDLINE | ID: mdl-19416775

ABSTRACT

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.


Subject(s)
Bronchiolitis Obliterans/diagnosis , Bronchiolitis Obliterans/immunology , Bronchoalveolar Lavage Fluid/immunology , Leukocyte Count , Lung Transplantation/immunology , Neutrophils/immunology , Postoperative Complications/diagnosis , Postoperative Complications/immunology , Adult , Biopsy , Bronchi/pathology , Bronchiolitis Obliterans/pathology , Bronchoscopy , Cohort Studies , Female , Graft Rejection/diagnosis , Graft Rejection/immunology , Graft Rejection/pathology , Humans , Interleukin-8/metabolism , Lung Transplantation/pathology , Male , Middle Aged , Neutrophils/pathology , Postoperative Complications/pathology , Predictive Value of Tests , Prognosis , Regression Analysis , Retrospective Studies , Risk Factors , Secretory Leukocyte Peptidase Inhibitor/metabolism
12.
Exp Clin Transplant ; 7(4): 261-3, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20353379

ABSTRACT

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.


Subject(s)
Coronary Artery Bypass, Off-Pump , Coronary Artery Disease/surgery , Heart Transplantation/adverse effects , Coronary Artery Bypass, Off-Pump/instrumentation , Coronary Artery Disease/etiology , Humans , Male , Middle Aged , Transplantation, Homologous , Treatment Outcome
13.
Exp Clin Transplant ; 6(3): 229-35, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18954302

ABSTRACT

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.


Subject(s)
HLA Antigens/immunology , Heart Transplantation/immunology , Isoantibodies/blood , Adult , Antibody Formation , Cardiomyopathy, Dilated/surgery , Enzyme-Linked Immunosorbent Assay , Female , Follow-Up Studies , Graft Rejection/epidemiology , Graft Rejection/immunology , Heart Transplantation/mortality , Humans , Male , Middle Aged , Retrospective Studies , Survival Analysis , Survivors , Time Factors , Tissue Donors
14.
Ther Drug Monit ; 30(4): 419-27, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18641552

ABSTRACT

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.


Subject(s)
Algorithms , Drug Monitoring/statistics & numerical data , Heart Transplantation/immunology , Immunosuppressive Agents/therapeutic use , Mycophenolic Acid/analogs & derivatives , Adult , Aged , Area Under Curve , Dose-Response Relationship, Drug , Female , Humans , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/pharmacokinetics , Male , Middle Aged , Mycophenolic Acid/administration & dosage , Mycophenolic Acid/pharmacokinetics , Mycophenolic Acid/therapeutic use , Predictive Value of Tests , Tacrolimus/pharmacokinetics , Tacrolimus/therapeutic use , Young Adult
15.
Eur J Echocardiogr ; 9(4): 494-500, 2008 Jul.
Article in English | MEDLINE | ID: mdl-17923438

ABSTRACT

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.


Subject(s)
Coronary Artery Disease/diagnostic imaging , Echocardiography , Heart Transplantation/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Transplantation, Homologous , Aged , Coronary Circulation , Coronary Vessels/diagnostic imaging , Feasibility Studies , Female , Humans , Male , Middle Aged , Radiopharmaceuticals , Technetium Tc 99m Sestamibi
16.
J Heart Lung Transplant ; 26(6): 598-603, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17543783

ABSTRACT

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.


Subject(s)
Heart Transplantation/immunology , Immunosuppressive Agents/therapeutic use , Sirolimus/therapeutic use , Tacrolimus/therapeutic use , Adrenal Cortex Hormones/administration & dosage , Adult , Drug Administration Schedule , Female , Follow-Up Studies , Graft Rejection/drug therapy , Graft Rejection/epidemiology , Heart Failure/surgery , Humans , Infections , Male , Middle Aged , Postoperative Complications/prevention & control , Prospective Studies , Time Factors
17.
J Nucl Med ; 47(9): 1413-9, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16954547

ABSTRACT

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.


Subject(s)
Diabetes Mellitus/physiopathology , Heart Transplantation/physiology , Heart/innervation , Heart/physiopathology , Nerve Regeneration/physiology , Sympathetic Nervous System/physiopathology , Catecholamines/metabolism , Diabetes Mellitus/diagnostic imaging , Female , Heart/diagnostic imaging , Humans , Male , Middle Aged , Myocardium/metabolism , Radionuclide Imaging , Recovery of Function/physiology
18.
Transplantation ; 81(3): 355-60, 2006 Feb 15.
Article in English | MEDLINE | ID: mdl-16477220

ABSTRACT

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.


Subject(s)
Bronchiolitis Obliterans/drug therapy , Graft Rejection/prevention & control , Immunosuppressive Agents/therapeutic use , Lung Transplantation , Mycophenolic Acid/analogs & derivatives , Sirolimus/therapeutic use , Adolescent , Adult , Calcineurin Inhibitors , Disease Progression , Female , Heart-Lung Transplantation , Humans , Immunosuppression Therapy/methods , Immunosuppressive Agents/adverse effects , Kidney/drug effects , Male , Middle Aged , Mycophenolic Acid/adverse effects , Mycophenolic Acid/therapeutic use , Sirolimus/adverse effects , Syndrome
19.
Eur Heart J ; 25(19): 1726-33, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15451151

ABSTRACT

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.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Heart Transplantation , Nerve Regeneration/physiology , Propranolol/therapeutic use , Sympathetic Nervous System/physiology , Exercise/physiology , Exercise Tolerance , Female , Hemodynamics , Humans , Male , Middle Aged , Positron-Emission Tomography , Transplantation, Homologous , Ventricular Function, Left/physiology
20.
J Heart Lung Transplant ; 23(5): 632-8, 2004 May.
Article in English | MEDLINE | ID: mdl-15135383

ABSTRACT

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.


Subject(s)
Bronchial Diseases/etiology , Immunosuppression Therapy/adverse effects , Immunosuppression Therapy/methods , Immunosuppressive Agents/administration & dosage , Lung Transplantation , Sirolimus/administration & dosage , Adrenal Cortex Hormones/administration & dosage , Adult , Graft Rejection/prevention & control , Heart-Lung Transplantation , Humans , Immunosuppressive Agents/adverse effects , Male , Middle Aged , Pilot Projects , Postoperative Complications , Prospective Studies , Sirolimus/adverse effects , Tacrolimus/administration & dosage , Wound Healing/drug effects
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