Search Results - (Author, Cooperation:H. Reichenspurner)

2014-04-22

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Angioplasty, Balloon/adverse effects ; Animals ; Aorta/drug effects/*injuries/pathology ; Apoptosis/drug effects ; Arteries/drug effects/*injuries/pathology ; Cell Proliferation/drug effects ; Constriction, Pathologic/pathology/*prevention & control ; Coronary Vessels/drug effects/injuries/pathology ; Dichloroacetic Acid/*pharmacology/*therapeutic use ; Disease Models, Animal ; Enzyme Activation/drug effects ; Gene Knockdown Techniques ; Humans ; Hyperplasia/drug therapy/pathology ; Iliac Artery/drug effects/injuries/pathology ; Mammary Arteries/drug effects/injuries/pathology ; Membrane Potential, Mitochondrial/drug effects ; Mitochondria, Heart/drug effects/metabolism ; Myocytes, Smooth Muscle/drug effects/pathology ; Protein-Serine-Threonine Kinases/antagonists & inhibitors/deficiency/genetics ; Rabbits ; Rats ; Secondary Prevention ; Stents/adverse effects ; Swine ; Tunica Intima/*drug effects/injuries/*pathology

1432-1440

Heart-transplantation

Springer Online Journal Archives 1860-2000

Medicine

Summary The first successful heart-transplantation carried out in the Department for Cardiovascular Surgery of the University of Munich, Klinikum Großhadern is reported. The recipient, 32 years old at the time of operation, had sustained a large antero-lateral-septal myocardial infarction in June 1980; thereafter the left ventricular ejection fraction was severely impaired (e.f.=19%). Yet, the operation was definitely planned some year later, after the patient had survived an embolus to the right lung, an acute left heart failure and a small ulcer of the stomach. The operation was performed on 8-19-1981. The donor was a 23 year old young man, who had met a fatal motorcycle accident 10 days ago. The man was pronouned dead in the afternoon of the preoperative day according to the criterions of the German Society for Surgery by means of a carotid angiogram. Donor and recipient were well matched in regard to blood group, HLA-A2-System and finally crossmatch-test. Transplantation was carried out according to the technique of Lower and Shumway. Immediately p.o., immunosuppressive therapy was started using azathioprine, cortisone and antihuman thymocyte globulin. Two acute rejections were noted, the first from p.o. day 6 to 15, the second from p.o. day 22 to 34. The second acute rejection was complicated by a pneumatosis cystoides intestinii, which caused a change of the immunosuppressive therapy to Cyclosporin A. No further complications were registered in the following p.o. course, the patient is discharged since Christmas 1981.

Electronic Resource

1432-2277

Key words Immunoadsorption ; Ig-Therasorb ; Hyperacute xenograft rejection ; Baboon ; Orthotopic xenotransplantation ; Xenoreactive antibodies

Springer Online Journal Archives 1860-2000

Medicine

Abstract To prevent hyperacute xenograft rejection (HXR) caused by preformed natural antibodies (XNAb) after orthotopic heart xenotransplantation (oXHTx) of landrace pig hearts into baboons, we used immunoadsorption of immunoglobulins IgG, IgM and IgA and complement with the reusable Ig-Therasorb column. In addition to functional data, tissue was sampled for histological, immunohistochemical and electron microscopical analysis. We performed three oXHTx of landrace pig hearts to baboons using extracorporeal circulation (ECC) connected to the immunoadsorption unit. Intraoperative treatment consisted of four cycles of immunoabsorption (IA). One oXHTx of a baboon without IA served as a control. A mismatch of donor and recipient heart size was prevented by selecting a 30–40 % lower body weight of donor pigs than recipients. Four cycles of IA removed more than 80 % of IgG, IgM and IgA, 86 % of anti-pig antibodies and 66 % of complement factors C3 and C4 from plasma. The graft of the control animal failed after 29 min. Orthotopic xenotransplantation with IA was selectively terminated after 100 min, 11 h and 21 h, respectively without any histological signs of HXR in light and electron microscopy. After weaning off from ECC these donor xenografts showed sufficient function with normal ECG and excellent cardiac output in echocardiography and invasive measurement (1.93 ± 0.035 l/min). The myocardium of the control xenograft demonstrated more deposits of Ig and complement components (C3, C4) than in the IA group. Baboons survive HXR after orthotopic pig heart xenotransplantation due to antibody depletion by reusable Ig-Therasorb column treatment. Long-term survival in an orthotopic baboon xenotransplantation model after IA, especially in combination with transgenic pig organs, could be a reliable preclinical trial for future clinical xenotransplantation programs.

Electronic Resource

1432-2277

Key words Ischemic time ; Hyperacute xenograft rejection ; Xenotransplantation ; Ig-Therasorb column ; Immunoadsorption

Springer Online Journal Archives 1860-2000

Medicine

Abstract In xenotransplantation long ischemic time of grafts is supposed to have a marked influence on hyperacute rejection (HXR). We investigated the influence of different cold ischemic times on HXR of ex vivo “working pig hearts” perfused with human blood. Xenoreactive natural antibodies (XNAb) as a trigger of HXR were eliminated by Ig-Therasorb immunoadsorption (IA). Explanted Landrace pig hearts of group G1 and group G3 (with additional IA) underwent 4 h of cold ischemia prior to xenoperfusion. Control groups G2 and G4 (with IA) were kept ischemic for only 46.6 ± 15.8 and 51.2 ± 4.2 min, respectively. Ischemic time prolonged the perfusion time in our working heart model (G1: 356 ± 46.1 min; G2: 125 ± 31 min; P 〈 0.05). IA had no additional impact on perfusion time but was effective by itself. The heart weight increased fourfold more in G2 as compared to the other groups. IA without ischemia significantly improved cardiac output in G4 (G3: 198.8 ± 15.4 mL/min; G4: 338.5 ± 16.0 mL/min). Coronary flow in G2 was significantly lower than in G1 (G1: 157.9 ± 9.15 mL/min; G2: 59.4 ± 20.1 mL/min). Histological signs of HXR (light and electron microscopy) could be found in G2 in contrast to the other groups. Parameters of serological damage showed a minimum in G4 and the maximum in G2. In G1 XNAb were nearly equally eliminated immediately after the start of xenoperfusion as in IA groups G4 and G3. Four hours of ischemic time showed beneficial effects in preventing HXR, possibly caused by changes of the endothelial cell surface (for example, glycosylation or loss of α1–3Gal epitopes with a hapten effect).

Electronic Resource

1573-0743

Springer Online Journal Archives 1860-2000

Medicine

Electronic Resource

1432-2277

Key words Troponin-T ; Cardiac rejection ; Heart transplantation ; Cardiac enzymes

Springer Online Journal Archives 1860-2000

Medicine

Abstract Non-invasive detection of cardiac rejection still remains a challenge after heart transplantation. We assessed troponin-T as a new serum marker to diagnose cardiac rejection. Twenty-five heart transplant patients (Berne) were monitored prospectively for up to 2 years, and compared to 89 retrospectively assessed patients (Stanford). Blood samples (392 Berne and 320 Stanford) were analyzed (creatine kinase, isoenzymes MB activity and MB mass, troponin-T and troponin-I). Regression analysis between the results of these blood samples and cardiac rejection grading from simultaneously performed endomyocardial biopsies was carried out. Troponin-T tests done in two different laboratories showed a good correlation (r = 0.91; P 〈 0.0001), whereas tropinin-T versus troponin-I showed a lower correlation (r = 0.53; P 〈 0.0001). Troponin-T and -I in contrast to other enzymes were elevated for a longer period (up to 4 weeks before returning to baseline) after transplantation than during conventional cardiac surgery. Beyond 3 months the following correlations were found between troponin-T (new or old test) and the other enzymes (creatine kinase: r = 0.26, MB activity: r = 0.4, and MB mass: r = 0.68). The correlation between the degree of rejection and the enzyme release is poor, however, the best results were obtained for troponin-T (r = 0.22; P 〈 0.001). We found a low correlation between troponin-T and the degree of rejection beyond 3 months after heart transplantation. Despite a troponin-T elevation in some patients with rejection, the new test is not sensitive enough to be used alone for the non-invasive diagnosis of cardiac rejection.

Electronic Resource

1432-2277

Key words Nitric oxide ; Endothelin ; Humans ; Heart transplantation ; Endothelial function

Springer Online Journal Archives 1860-2000

Medicine

Abstract Endothelial dysfunction precedes and predicts transplant vasculopathy. We investigated the relationship between endothelial dysfunction and the vasoactive mediators nitric oxide and endothelin, 33.7 ± 2.0 days after heart transplantation. Coronary flow was measured in 18 patients to determine the endothelial microvascular vasomotor response to acetylcholine. Endomyocardial biopsies were taken to determine the levels of gene expression of isozymes of endothelin and nitric oxide synthases (NOS). Blood samples from the coronary sinus and aorta were withdrawn for measurement of endothelin, nitrite and cytokines. Five patients (30 %) showed an impaired coronary flow reserve response to acetylcholine, significantly higher inducible NOS gene expression and significant transcardiac nitrite production. Plasma nitrite correlated with tumour necrosis factor-alpha levels in coronary sinus and a transcardiac net extraction of endothelin was noted in all patients. In conclusion, 30 % of patients develop endothelial dysfunction early after heart transplantation; this correlates with the expression and activation of vasoactive and immunomodulatory mediators, which may predict the development of transplant vasculopathy.

Electronic Resource

1435-1285

Key words Pseudoaneurysm – Bentall procedure – aorto ascendens replacement – ultrafast-CT ; Schlüsselwörter Pseudoaneurysma – Bentall’sche Operation – Aorta ascendens Ersatz – Ultrafast-CT

Springer Online Journal Archives 1860-2000

Medicine

Zusammenfassung Pseudoaneurysmen sind eine seltene Komplikation nach prothetischem Ersatz der Aorta ascendens und aorto-koronaren Bypass Operationen. Wir stellen ein Fall vor, bei dem nach Ersatz der Aortenklappe, der Aorta ascendens und Anlage zweier venöser aorto-koronarer Bypässe ein großes Pseudoaneurysma von einer der proximalen Bypass-Anastomosen ausging. Die präoperative Diagnose sowie die Darstellung der epikardialen Koronargefäße wurde mittels Ultrafast-CT (Electron Beam Tomography, EBT) gesichert, da weder das Pseudoaneurysma, noch der aus ihm hervorgehende venöse Bypass bei der Koronarangiographie selektiv darstellbar waren.

Summary Pseudoaneurysms are a rare complication following replacement of the ascending aorta or aorto-coronary bypass surgery. We report a case with replacement of the aorta ascendens, the aortic valve, and venous aorto-coronary bypass grafting, in whom a pseudoaneurysm developed at the site of one proximal bypass anastomosis. For the preoperative diagnosis, an ultrafast-CT (Electron Beam Tomography, EBT) was done, as neither the pseudoaneurysm, nor the venous graft could be visualized by selective coronary angiography.

Electronic Resource

1435-2451

Rejection ; Cyclosporin A ; Heart transplantation ; Abstoßungsreaktion ; Herztransplantation

Springer Online Journal Archives 1860-2000

Medicine

Zusammenfassung Um die Auswirkungen von Cyclosporin A (CyA) auf die Abstoßungsmechanismen und die Überlebenszeit bei xenogener Herztransplantation zu untersuchen, wurde als Modell die heterotope intrathorakale Herztransplantation gewählt. Als Spender dienten Rotfüchse (6–8 kg), als Empfänger Mischlingshunde (15–22 kg). Abstoßungskrisen konnten mit Hilfe des cytologisch-immunologischen Monitorings und der Herzmuskelbiopsie nachgewiesen werden. Die Überlebenszeit der Transplantate betrug 18,5±3,2 Tage. Von 8 Empfängern zeigten 2 Versuchstiere celluläre (25%), 2 humorale (25%) und 3 cellulär-humorale (38%) Abstoßungsmechanismen. Ein Versuchstier wies keine Transplantreaktion auf. Humorale Abstoßungen verliefen fulminant und therapieresistent, bei humoral-cellulären Reaktionen konnte mit hochdosierter Methylprednisolongabe (250 mg/Tg) ein Organverlust verzögert werden.

Summary In order to look at the effects of Cyclosporine A on the mechanisms of rejection after xenogeneic heart transplantation, the model of heterotopic intrathoracic cardiac transplantation was used. Red foxes (6–8 kg) served as donors, mongrels (15–22 kg) as recipients. Rejection was detected by cytoimmunological monitoring and endomyocardial biopsy. Mean survival time was 18.8±3.2 days (historic control 8.4± 1.9 days). Of 8 animals, 2 developed cellular rejection mechanisms (25%), 2 others developed humoral (25%) and 3 cellular and humoral (38%). One animal showed no signs of rejection. Humoral rejection episodes were not be influenced by high dosages of methylprednisolone (250 mg/day), while cellular rejections could be successfully controlled.

Electronic Resource

1435-1285

Schlüsselwörter Minimal-invasive Herzchirurgie – neue Operationsverfahren – MIDCAB – Port-Access-Technik ; Key words Minimally invasive cardiac surgery – ne surgical techniques – MIDCAB – Port-Access technique

Springer Online Journal Archives 1860-2000

Medicine

Summary Within the last 5 years new less invasive surgical techniques have been developed in the field of cardiac surgery. This new field named minimally invasive cardiac surgery can be subdivided into techniques which do not require cardiopulmonary bypass and are used mainly for coronary artery surgery (called minimally invasive direct coronary artery surgery, MIDCAB technique). This MIDCAB procedure can be done through a small left anterior thoracotomy or a sternotomy. In addition there are other methods which allow the performance of complex cardiac surgery through small accesses in combination with the use of an endovascular CPB system and internal aortic clamping to achieve cardioplegic arrest (so-called Port-Access method). Also for valvular surgery, new surgical techniques were developed allowing access to mitral and aortic valves through limited incisions. In addition, new less invasive techniques were developed for congenital heart surgery. This article will describe the various surgical techniques and define the indications for minimally invasive cardiac surgery.

Zusammenfassung In den letzten 5 Jahren sind im Bereich der Herzchirurgie neue, weniger invasive Operationsverfahren entwickelt worden, die unter dem Oberbegriff minimal-invasive Herzchirurgie zusammengefaßt werden. Man unterscheidet dabei Verfahren, die auf die Anwendung der extrakorporalen Zirkulation verzichten und in erster Linie in der Koronarchirurgie zum Einsatz kommen (sogenannte minimal-invasive direkte koronare Bypasschirurgie oder MIDCAB-Verfahren). Diese Operation kann entweder über eine kleine Thorakotomie oder über eine volle Sternotomie vorgenommen werden. Demgegenüber gibt es Operationstechniken, bei denen über einen limitierten Zugang ein endovaskuläres Bypass-System zum Einsatz kommt und ein Abklemmen der Aorta ascendens mit Gabe von kardiopleger Lösung möglich ist (sogenannte Port-Access-Technik). Auch in der Klappenchirurgie sind in den letzten Jahren verschiedene Operationsverfahren entwickelt worden, welche den Zugang zur Herzklappe über eine limitierte Sternotomie oder kleine Thorakotomie ermöglichen. In der Chirurgie kongenitaler Vitien sind ebenfalls weniger invasive Operationsverfahren zum Einsatz gekommen. Dieser Artikel soll nun die einzelnen Operationsverfahren näher beschreiben und die Indikationen für diese Eingriffe definieren.

Electronic Resource