Search

Background: Ethical and medical criteria in the decision-making process of withholding or withdrawal of life support therapy in critically ill patients present a great challenge in intensive care medicine., Objectives: The purpose of this work was to assess medical and ethical criteria that influence the decision-making process for changing the aim of therapy in critically ill cardiac surgery patients., Materials and Methods: A questionnaire was distributed to all German cardiac surgery centers (n = 79). All clinical directors, intensive care unit (ICU) consultants and ICU head nurses were asked to complete questionnaires (n = 237)., Results: In all, 86 of 237 (36.3 %) questionnaires were returned. Medical reasons which influence the decision-making process for changing the aim of therapy were cranial computed tomography (cCT) with poor prognosis (91.9 %), multi-organ failure (70.9 %), and failure of assist device therapy (69.8 %). Concerning ethical reasons, poor expected quality of life (48.8 %) and the presumed patient's wishes (40.7 %) were reported. There was a significant difference regarding the perception of the three different professional groups concerning medical and ethical criteria as well as the involvement in the decision-making process., Conclusion: In critically ill cardiac surgery patients, medical reasons which influence the decision-making process for changing the aim of therapy included cCT with poor prognosis, multi-organ failure, and failure of assist device therapy. Further studies are mandatory in order to be able to provide adequate answers to this difficult topic.

The current report highlights the use of venoarterial extracorporeal membrane oxygenation (va-ECMO) in a case of pulmonary embolism complicated by right ventricular failure. A 38-year-old woman was admitted to a secondary care hospital with dyspnea and systemic hypotension. Diagnostic testing revealed a massive pulmonary embolism. Thrombolytic therapy was unsuccessful necessitating thromboendarterectomy in the presence of cardiogenic shock. To allow the necessary transport of the highly unstable patient to a tertiary care center a mobile ECMO team was called in. The team immediately initiated awake va-ECMO as a bridge to therapy. Extracorporeal support subsequently allowed a safe transportation and successful completion of the surgical procedure with complete recovery.

Purpose: An important rehabilitation aim following coronary artery bypass graft (CABG) surgery is to modify cardiovascular risk factors positively. Among the most potent possibilities for improvement of these factors is a lifestyle change in terms of increasing sports exercise, changing diet patterns, stress reduction, etc. An indispensable condition for these changes is the motivation to implement the necessary changes. In our working group a patient education programme was developed aimed at enhancing the motivation for lifestyle change, which was already applied in a cardiac surgery hospital. In evaluating the programme, we could observe that various cognitive factors of motivation for lifestyle change had dropped in untreated patients and risen in patients participating in the programme. Based on these preliminary findings we examined the motivation for lifestyle change one year after CABG surgery., Method: Each patient was evaluated for his/her value in motivation for lifestyle change using a 30-item questionnaire which measures the six factors Vulnerability, Intention, Social Expectations, Outcome Expectation, Self-Efficacy Expectation, and Perceived Severity two days before CABG surgery as well as ten days and one year after CABG surgery. Between January and May 2002 patients in usual care were investigated as control group (n=70). From January to May 2003, n=70 patients had the opportunity to take part in a comprehensive patient education programme that was provided by a specifically trained psychologist. Data from 108 patients could be evaluated one year after CABG surgery (response rate=77.1%). The programme had comprised individualized units, as well as a group lecture. If partners were available they were included in the process., Results: One year after CABG surgery no significant differences between the control group and the intervention group could be found., Conclusion: The positive effects of the patient education programme measured ten days after surgery were found to have vanished one year after the operation. A possible reason is the short duration of the programme. Long-term, structured aftercare programmes should help stabilize the positive effects obtained in the short term.

Background and Purpose: Patients with aortic valve (AV) pathology and severe comorbidities should benefit from reduced myocardial ischemic and extracorporeal circulation (ECC) time. Sutureless implantation of AV prosthesis may reduce myocardial ischemic and ECC time significantly. The authors report on their preliminary results with the first implants of the 3F-Enable sutureless AV prosthesis., Material and Methods: The 3F-Enable prosthesis was implanted in five patients. Prostheses sizes were 27 mm (n = 3), 23 mm (n = 1), and 21 mm (n = 1), respectively. Intraoperatively, at patient's discharge as well as 3 and 6 months postoperatively, the AV prosthesis was evaluated by echocardiography., Results: ECC time was 87 +/- 36 min (range 49-141 min), myocardial ischemic time 55 +/- 27 min (range 32-97 min), and AV implant time 184 +/- 195 s (range 10-420 s). The latest postoperative echo (5.2 +/- 1 months postoperatively) revealed a fully competent AV in three patients, in two patient paravalvular leakage was detected at the severity of an aortic regurgitation (AR) II degrees , and AR II degrees -III degrees , respectively. The mean pressure gradients were 5.8 +/- 1.3 mmHg (range 4.2-7.1 mmHg), valve orifice area was 3.2 +/- 0.4 cm2 (range 2.6-3.6 cm2)., Conclusion: The first clinical results of the 3F-Enable sutureless AV prosthesis are feasible; however, a paravalvular leakage was detected in two patients (40%). Thus, device and procedural enhancements are required to assure positioning and anchoring of the prosthesis.

Background and Purpose: The endothelial lining is a confluent monolayer of thin and rhomboid-shaped cells, that covers the inner surface of all blood vessels. However, the essential role of endothelial cells in all aspects of cardiovascular physiology, homeostasis and the pathogenesis of most cardiovascular diseases no longer remains controversial. Although much evidence has been achieved regarding the molecular functioning of transcription factors and regulatory proteins, many questions on endothelial heterogeneity with regard to function and morphology at various vascular sites remain unanswered. In this study, an immunohistochemical map of endothelial adhesion molecule expression at various vascular sites of the healthy human heart is created. Using this map, the authors examined whether expression patterns are distinctive by their molecular function at their site of origin. Furthermore, immunohistochemical findings were associated with the clinical situation., Material and Methods: Tissue samples from eleven different vascular locations of healthy human hearts were analyzed using immunohistochemistry. Endothelial adhesion molecules of the selectin, immune globulin supergen, and integrin families, some complementary cellular adhesion molecules, and the von Willebrand factor were analyzed., Results: Endothelial adhesion molecule expressions were found to be characteristic of all vascular sites investigated. Thus, molecules involved in inflammatory reactions were predominantly expressed within the myocardial microvasculature, whereas molecules serving for endothelial anchorage toward extracellular matrix components could be observed especially on endocardial and valvular surfaces. Apart from that, a parallel expression of immunologically relevant as well as integrin molecules were found to be characteristic of coronary arteries., Conclusion: To the authors' knowledge, this is the first report on site-specific expression characteristics for all vascular sites of the human heart. Thus, our data provide important novel information, which ultimately will help to bring some light into the field of cardiac physiology.

Background: The ideal scaffold material for tissue engineered heart valves is discussed controversially. We evaluated acellularized xenogenic matrix constructs with and without seeding with autologous vascular cells in the pulmonary circulation in a sheep model., Methods: Porcine pulmonary valve conduits (n=16) were acellularized by trypsin/ EDTA incubation. Autologous myofibroblasts and endothelial cells were harvested from carotid arteries; xenogenic valve conduits (n=10) were repopulated with these autologous cells resulting in uniform cellular restitution of the pulmonary valve conduit surface. Using this method, we implanted autologous cell/xenogenic matrix constructs (XB) in ten animals. In six control animals acellularized/xenogenic matrix constructs (XA) were implanted. In each animal, cardiopulmonary bypass was used to resect the pulmonary valve and replace it with the xenogenic pulmonary valve conduits. The animals were killed after 6, 9 or 12 months. The explanted valves were examined histologically and biochemically., Results: After explantation XB showed severe cusp degeneration, which resulted in severe valvular regurgitation. In comparison, XA appeared macroscopically normal with preserved valvular function. The surface of XB were covered with an incomplete endothelial multilayer. The extracellular matrix (ECM) of XB showed pathological amounts of collagenous and elastic fibers as well as proteoglycan content combined with an increase cellularity. The XA were completely repopulated by an endothelial cell monolayer; the ECM was repopulated with a myofibroblast population comparable to native ovine heart valve tissue., Conclusions: Approaches to heart valve engineering based on acellularized/xenogenic matrices provide promising results and will hopefully led to the "ideal" valve substitute in clinical heart valve replacement.

Objectives: After a period of 5 to 10 years, biological heart valve prostheses undergo degenerative processes, which finally lead to dysfunction and complete destruction. Although many efforts have been made to identify underlying mechanisms, many questions remain unanswered. Here we evaluate immunological factors and their potential role in biological heart valve destruction., Patients and Methods: Allogeneic (n=10) and xenogeneic (n=3) aortic valvular prostheses, as well as aortic valves retrieved from transplanted human hearts, which had to be replaced because of chronic graft rejection (n=4) were analyzed. Aortic valves from human donor hearts (native) (n=4), which were considered not transplantable served as controls. Endothelial expression patterns of the following adhesion molecules were analyzed by immunohistochemistry: selectin family: ELAM-1, CD62, integrin family: VLA-1, -2, -3, -4, -5, and -6, immunoglobulin supergene family: PECAM-1, ICAM-1, and -2, and class I heavy chain proteins, complementary adhesion molecules: CD34, CD44 and the von Willebrand factor., Results: ELAM-1, ICAM-1 and -2, CD34, CD44 and class I heavy chain proteins, all molecules which play significant roles during inflammatory processes, showed stronger expression patterns in allogeneic and xenogeneic aortic heart valve prostheses compared to native or chronically rejected valves. Furthermore, the von Willebrand factor stained positive only on allogeneic and xenogeneic valves. Only mild differences were observed regarding the expression of integrin molecules and CD62., Conclusions: Immunological reactions play a major role in the degeneration of biological heart valve prostheses. This is underlined by observations made on aortic valves from chronically rejected cardiac grafts, which did not show any degenerative alterations. Thus, since immunosuppressive therapy after heart valve replacement is no reasonable alternative, novel and future approaches in "tissue engineering" will hopefully help avoid tissue degeneration, while preserving the advantage of biological tissue origin.

Endoaneurysmorrhaphy (EAR) in postinfarct ventricular aneurysms leads to excellent short-term results. However, the temporal response of EAR is widely unknown. Thus, the indication for surgical treatment of patients with ventricular aneurysms is not well defined. EAR was performed in 157 patients (6/1993-6/1999) with symptomatic ventricular aneurysms (median NYHA III). Factors influencing cardiac mortality and morbidity during follow-up were determined by univariate and multivariate analysis. Perioperative mortality was low: 5%. Mortality during follow-up was 3.3% per year, resulting in a 5-year survival rate of 78%. NYHA classification ameliorated significantly from the preoperative status compared to the follow-up period (median NYHA II; p < 0.001). Multivariate analysis identified preexisting arterial occlusive disease and advanced age (> 70 years) as significant factors influencing medium-term mortality. Implantation of the left internal mammary artery was associated with a better survival rate. Endoaneurysmorrhaphy can be performed with low perioperative mortality, will result in a significant amelioration of the cardiac clinical status and offers low medium-term mortality. Our data indicate that EAR seems to be the procedure of choice for patients with symptomatic ventricular aneurysms.

The long-term performance of two different types of flexible aortic prostheses was evaluated in 10 patients who received a stentless porcine prosthetic valve (group A) and in 18 patients who underwent aortic valve replacement with an aortic homograft (group B). In group A early postoperative angiography (5-16 days post surgery) revealed a mean gradient across the aortic prosthesis of 8 +/- 6 mmHg. Late postoperative Doppler echocardiography (3.2 +/- 0.9 years post surgery) suggested a mean gradient of 6 +/- 3 mmHg with a Doppler derived valve orifice area of 1.8 +/- 0.6 cm2. Color Doppler visualized mild prosthesis regurgitation in two of the 10 patients and two-dimensional imaging showed no significant leaflet calcification. In group B late postoperative Doppler echography (5.2 +/- 1.6 years post surgery) suggested a mean gradient of 11 +/- 14 mmHg with a mean graft orifice area of 1.8 +/- 0.5 cm2. Color Doppler revealed prosthesis regurgitation in 15 patients (severe 1, moderate 2, mild 12) and two-dimensional imaging visualized significant prosthesis leaflet calcification in two patients. The good hemodynamic function of a stentless porcine bioprosthesis which seems to be preserved for at least several years indicates that the use of the flexible aortic xenograft is worthwhile pursuing. The long-term performance of an aortic homograft is relatively poor and may be due to unsolved problems with regard to sterilizing and storing the valves.