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Helmut Gulbins

Publications and source records attributed to Helmut Gulbins.

17 recordsLinked to original sources
PubMed2006

Successful endothelialization of porcine glutaraldehyde-fixed aortic valves in a heterotopic sheep model.

PURPOSE: The purpose of our study was to evaluate the stability of an artificially seeded endothelial cell layer on porcine aortic prostheses under in vivo conditions in the arterial system. DESCRIPTION: Ten female sheep were divided into two groups. Animals of the study group (n = 7) had dissection of their right external jugular vein for cell harvesting. Myofibroblasts and endothelial cells were labelled with PKH-26, seeded onto pretreated (10% citric acid) porcine glutaraldehyde-fixed aortic valves (Freestyle, Medtronic Inc, Duesseldorf, Germany), and the valves were implanted into the descending aorta. Controls (n = 3) received pretreated but unseeded valves. A shunt between the aortic arch and the left atrial appendage ensured systolic or diastolic leaflet motions, or both, that were documented by sonography. After 3 months the valves were explanted. Specimens for scanning electron microscopy and immunohistochemical staining were taken prior to implantation and after explantation. EVALUATION: A neointimal proliferation was detected in the control group. No endothelial cells were found on the leaflets and the sinuses, but erythrocytes and thrombocytes were seen entrapped within the collagen fibers. Thrombus formation was documented macroscopically and histologically on the leaflets and the sinuses. In the study group a confluent endothelial cell layer was documented on the walls and leaflets. Neither neointimal proliferation nor any clots were seen. Some cells were still labelled positively indicating their origin from the initial cell seeding. No dilatation of any prosthesis was observed, but all valves showed slight thickening of the leaflets. CONCLUSIONS: The artificially seeded endothelial cell layers remained stable under in vivo conditions in the arterial system. Biocompatibility of the prostheses seemed to be improved by reduction of thrombogenicity.

Animals↗
PubMed2005

Seeding of human endothelial cells on valve containing aortic mini-roots: development of a seeding device and procedure.

PURPOSE: Complete covering of an artificial valvular scaffold with endothelial cells may prevent thromboembolic complications and lead to an excellent biocompatibility. For this purpose, we developed a seeding device for reproducible cell seeding on valve containing aortic roots. DESCRIPTION: Human endothelial cells and fibroblasts were obtained from saphenous vein pieces. Cryopreserved aortic roots (n = 25) were put into an especially developed tube, set on a rotator, and incubated with the cell suspension. The device rotated in two axes (sagittal and axial), ensuring slight movements of the leaflets. The rotation alternated with resting periods, allowing cell attachment to the surface. Different resting periods were tested (groups 1, 2, and 3 were 30, 45, and 60 min, respectively; n = 5 each). Total incubation time was 24 hours followed by further culturing for 6 days. In two further groups (groups 4 and 5; n = 5 each), a modified inlay was used to allow the cell suspension to flow around the entire graft. In group 4 the grafts were again incubated with human endothelial cells; however, in group 5 pre-seeding with autologous fibroblasts was done in addition. Immunohistochemical staining with antibodies against factor VIII, CD31, laminin, collagen IV, and CD90 were done, and scanning electron microscopy was done after initial seeding and after 6 days in culture. EVALUATION: Seeding resulted in homogenous cell layers on the luminal surface of the free walls in all groups. With resting periods of 45 minutes, these results were also obtained on the leaflets, whereas the other resting times resulted in defects of the endothelial cell layer on the cusps. After 6 days under culture conditions, the endothelial cell layers were confluent and viable, with the exception of the leaflets in group 1. With the modified inlay (groups 4 and 5), confluent cell layers were also achieved on the outer surface. In group 5 pre-seeding with autologous fibroblasts resulted in enhanced synthesis of extracellular matrix proteins, as was demonstrated with immunohistochemical staining for collagen IV and laminin. CONCLUSIONS: With this newly developed seeding device, confluent cell layers on valve containing aortic roots were reproducibly achieved. The technique enables further experimental research and even clinical application.

Aortic Valve↗
PubMed2005

An image of mitral valve repair.

Mitral regurgitation is a severe problem of the mitral valve mechanism caused by many factors, including ischemic and nonischemic cardiomyopathy, inflammation, degeneration and others. Regardless of the cause of valve dysfunction, many changes in surgical approach have been undertaken. The pioneering work of Carpentier led to the era of mitral valve reconstruction a few decades ago. Understanding the different techniques applied in several pathoanatomic settings is of major interest. This review summarizes the indications and results of this specific surgical procedure in the setting of ventricular dysfunction by different causes.

Cardiac Surgical Procedures↗
PubMed2004

Development of an artificial vessel lined with human vascular cells.

OBJECTIVES: Thrombogenity of small-diameter vascular prostheses might be reduced by complete coverage of the luminal surface with vascular cells. We investigated cell seeding on polyurethane vascular prostheses. METHODS: Thirty polyurethane vascular prostheses were divided into 3 groups of 10 each: group A, diameter of 20 mm and gamma-sterilized; group B, diameter of 4 mm and gamma-sterilized; and group C, diameter of 4 mm and ethylene oxide sterilized. Human smooth muscle cells, fibroblasts, and endothelial cells were isolated from saphenous vein segments and expanded in culture. Five polyurethane vascular prostheses of each group were seeded with endothelial cells alone (mean, 4.8 +/- 1.2 x 10(6) cells), and the remaining 5 polyurethane vascular prostheses were preseeded with a mixed culture of fibroblasts and smooth muscle cells (mean, 7.7 +/- 2.3 x 10(6) cells), followed by endothelial cell seeding (mean, 4.4 +/- 0.9 x 10(6) cells). Seven days after cell seeding, the polyurethane vascular prostheses were perfused under a pulsatile flow (80 pulses/min, 140/80 mm Hg, and 120 mL/min) for 2 hours. Specimens were taken after each seeding procedure both before and after perfusion and then examined both with a scanning electron microscope and immunohistochemically. RESULTS: Isolated endothelial cell seeding revealed better initial adhesion in groups A and B than in group C (63% vs 33%). After 7 days, the cells had covered approximately 80% of the luminal surface in groups A and B, whereas group C cells rounded up and lost adhesion. After perfusion testing of group A and B prostheses, only 10% of the surface was still covered with endothelial cells. Preseeding with the mixed culture again revealed a better initial adhesion in groups A and B compared with that in group C (76% vs 41%). In groups A and B endothelial cell seeding (adhesion, 72%) resulted in a confluent endothelial cell layer. The results of immunohistochemical staining were positive for collagen IV, laminin, CD31, and Factor VIII. In group C only isolated cells were found after each seeding procedure, which rounded up and vanished during the next days. Perfusion testing of group A and B prostheses revealed that the confluent cell layer remained stable, with only small defects (<10% of the surface). The cells stained positivively for endothelial nitric oxide synthase. CONCLUSION: Seeding of a mixed culture out of fibroblasts and smooth muscle cells resulted in improved endothelial cell adhesion and resistance to shear stress. This outcome was caused by an increased synthesis of extracellular matrix proteins. Cell attachment was better on gamma-sterilized polyurethane vascular prostheses compared with on those undergoing ethylene oxide sterilization.

Bioartificial Organs↗
PubMed2004

Minimally invasive heart valve surgery: already established in clinical routine?

Cardiac valve replacement with the need for open heart surgery still has the highest morbidity and mortality rates among routine cardiac surgery, with the exception of aortic aneurysm repair and surgery for congenital heart defects. Reducing invasiveness is a desirable goal, and different strategies and approaches have been used to achieve this with valve repair or replacement less invasive. Despite the good results reported with minimally invasive techniques, time on extracorporal circulation is always longer compared with the conventional procedures. Since these techniques do not reduce real invasiveness but rather improve the cosmetic results, minimal-access surgery would be a better nomenclature. With the exception of patients at a high risk for sternal infections or redo heart operations, a reduction in postoperative morbidity by the avoidance of a median sternotomy is not yet definitely proven. Meanwhile, most surgeons comply with the demand for minimally invasive surgery posed by patients by reducing the length of the incision in aortic valve replacement and by using a right anterolateral approach with a limited incision for mitral valve operations. However, the use of endoscopic or robotic devices is limited to a few centers, and has not yet found its way into clinical routine. Nonetheless, minimally invasive or minimal-access surgery is now established in many centers, and patients should always be informed of these techniques. When this information is provided objectively and patient selection is carried out accurately, these alternative approaches can help to improve postoperative convalescence.

Adult↗
PubMed2004

Ten years' experience in aortic valve replacement with homografts in 389 cases.

BACKGROUND AND AIM OF THE STUDY: Aortic valve replacement using homografts is an accepted alternative to the use of other replacement devices, and has been established at the authors' institution for more than 10 years. METHODS: Since 1992, a total of 389 homografts was implanted, and 332 patients (mean age 54 years, 72% males) were followed up. The initial patients (n = 75) had subcoronary implantation, all subsequent patients had root replacement. Both aortic grafts (AG) and pulmonary grafts (PG) were used. Follow up was conducted with regard to the factors 'graft origin', 'implantation technique' and 'gender', and included clinical examination, ECG and transthoracic echocardiography on an annual basis. RESULTS: Overall 30-day mortality was 5.4% (AG patients 3.9%, PG patients 13.5%; p = 0.09). Among late deaths (n = 22), six were valve-related (all prosthetic infection). Four minor thrombembolic events were recorded due to amaurosis fugax and transient ischemic attacks (TIA). Freedom from reoperation was 86.5%. Indication for graft replacement was greater after subcoronary implantation than after root implantation (p = 0.04). Reoperation was necessary in 24 patients due to restenosis (n = 4), regurgitation grade >II (n = 5), paravalvular leak (n = 2) and prosthetic infection (n = 13). At the latest echocardiographic follow up, mean peak pressure gradient was 15.60 +/- 11.76 mmHg, homograft regurgitation grade was 0.82 +/- 0.66, left ventricular end-diastolic diameter (EDD) was 49.1 +/- 7.54 mm, and mean aortic root diameter was 30.54 +/- 5.48 mm. When comparing parameters at a mean of five years postoperatively, the pressure gradient increased from 10.26 to 15.02 mmHg, regurgitation grade increased from 0.53 to 0.81, and EDD decreased from 52.3 to 50.4 mm. Other variables showed no significant differences. CONCLUSION: The present results confirmed good midterm-results for aortic valve replacement with homografts. These prostheses are vulnerable to infection, and root replacement was superior to the subcoronary implantation technique.

Adolescent↗
PubMed2003

Improved results after heart-lung transplantation: a 17-year experience.

OBJECTIVE: In selected patients with severe end-stage combined cardiopulmonary diseases, heart-lung transplantation (HLTx) remains the only therapeutical option for improving survival and quality of life. PATIENTS AND METHODS: Since 1983, 51 HLTx were done at our institution. Mean patient age was 27+/-12 years with a mean donor age of 25+/-11 years. Indications for HLTx were primary pulmonary hypertension (PPH) in 49% of patients, congenital heart disease in 39%, cystic fibrosis in 6%, and repeat-HLTx in 6%. Eleven patients were younger than 14 years. Among these pediatric patients, the indications were PPH in 55% of patients, pulmonary atresia with severe pulmonary artery hypoplasia in 27%, and cystic fibrosis and cardiomyopathy with fixed pulmonary hypertension in 9% of patients each. Two patients had additional liver transplantation because of chronic aggressive virus hepatitis. For organ preservation, Euro-Collins solution (lung perfusion) and cardioplegic solution according to Bretschneider (heart perfusion) were used until 1994. The University of Wisconsin solution replaced Bretschneider's solution in 1994. Since 1996, Perfadex, a low-potassium dextran-based preservation solution, replaced Euro-Collins. All transplantations were done through a median sternotomy until 1994. Thereafter, a transverse thoracotomy was used in patients with suspected adhesions. Until 1995, cyclosporine A, azathioprine, and prednisolone were used for immunosuppression. Since then, tacrolimus replaced cyclosporine A. RESULTS: From 1983 until 1993, perioperative mortality was 35% (6/19). From 1994 on perioperative mortality decreased to 12.5% (4/32). Early mortality was caused by graft failure (n=5), severe bleeding (n=2), multi-organ failure (n=2), and acute rejection (n=1). Cumulative survival rates were 81% after 30 days, 63% after 1 year, and 54% after 5 years, respectively. Since 1994, cumulative survival rates were markedly improved to 87% after 30 days, 81% after 6 months, and 78% after 1 year. There was no death during the first postoperative year among the 11 pediatric patients. Late death was mainly caused by obliterative bronchiolitis (OB; 76%); two patients died because of multi-organ failure or septic complications, respectively, and one patient died within the first postoperative year because of aspergillosis. CONCLUSION: Changes in organ preservation management, surgical techniques, and immunosuppressive therapy significantly improved the short- and mid-term results after HLTx. Long-term results can only be improved in cases of successful prevention and treatment of OB.

Adolescent↗
PubMed2003

Preseeding with autologous fibroblasts improves endothelialization of glutaraldehyde-fixed porcine aortic valves.

OBJECTIVE: This study represents the development of a treatment and seeding procedure to improve endothelial cellular adhesion on glutaraldehyde-fixed valves. METHODS: Porcine aortic valves were fixed with 0.2% glutaraldehyde. Wall pieces of these valves had either no additional treatment (n = 4), incubation in M199 Earle (1x), with sodium carbonate at 2.2 g/L without l-glutamine for 24 hours (n = 4), or additional pretreatment with 5%, 10%, or 15% citric acid (three groups, n = 4 each). Thereafter the pieces were washed and buffered to a physiologic pH. This was followed by seeding of human endothelial cells (5 x 10(6) cells). On the basis of the results of these pilot tests, complete glutaraldehyde-fixed aortic roots treated with 10% citric acid were subjected to cell seeding. The valves were seeded with endothelial cells (4.3 x 10(6) cells) either alone (n = 4) or in combination with preseeding of autologous fibroblasts (2.4 x 10(7) cells, n = 4). After each seeding procedure specimens of the free wall of the grafts were taken. In addition, one leaflet was taken for histologic examination after endothelial cell seeding, after 7 days, and after 21 days. Finally, two commercially available stentless aortic valve prostheses (Freestyle; Medtronic, Inc, Minneapolis, Minn) were treated with 10% citric acid and seeded with human fibroblasts and endothelial cells. Specimen were taken according to the glutaraldehyde-fixed aortic roots. Specimen of all experiments were examined with scanning electron microscopy. Frozen sections were stained immunohistochemically for collagen IV, factor VIII, and CD31. RESULTS: On untreated glutaraldehyde-fixed aortic wall pieces, only poor adhesion (24%) was seen. No viable cells were found after 1 week. Cellular adhesion was best on aortic wall pieces pretreated with 10% citric acid. After 7 days, the cells formed a confluent layer. Endothelial cell seeding on citric acid-treated complete aortic valves showed 45% adhesion, but no confluent layer was found after 1 week. Preseeding of these valves with autologous fibroblasts resulted in an endothelial cellular adhesion of 76% and a confluent endothelial cell layer after 7 days. The layer remained stable for at least 21 days. Results of staining for collagen IV, factor VIII, and CD31 were positive on the luminal side of these valves, indicating the synthesis of matrix proteins and viability of the cells. Pretreatment of commercially available porcine valves with 10% citric acid and preseeding with autologous fibroblasts followed by endothelial cell seeding resulted in an adhesion of 78%. The cells formed a confluent cell layer after 7 days. CONCLUSIONS: Pretreatment of glutaraldehyde-fixed porcine aortic valves with citric acid established a surface more suitable for cellular attachment. Preseeding these valves with autologous fibroblasts resulted in a confluent endothelial cell layer on the luminal surface. Flow tests and animal experiments are necessary for further assessment of durability and shear stress resistance.

Aldehydes↗
PubMed2003

Homografts: a review.

Since their introduction into clinical practice in 1965 homografts have become established in clinical routine. The storing and sterilization procedures have been improved over time. Long-term results showed that homografts had a superior durability compared to xenogenic biological prostheses. Approximately 40% were still in place 20 years after implantation in aortic position. Their low rate of thromboembolic events made a life-time anticoagulative therapy unnecessary and their hemodynamics were superior to all other heart valve prostheses. There exist two implantation techniques, subcoronary or mini-root, both technically more demanding compared with implantation of stented valve prostheses. When using the subcoronary technique, the valve is suspended into the aortic root leaving the coronary arteries untouched. The success of this technique, however, depends on the relation of the recipients aortic root and the implanted valve. The mini-root technique requires reimplantation of the coronary arteries but left the morphology of the valve and its root unchanged. Especially in patients with endocarditis, the mini-root technique offered the advantage of allowing for excision of all affected tissue with subsequent replacement by the homograft. The Ross-procedure uses the patient's own pulmonary valve as aortic valve substitute with implantation of a homograft in pulmonary position. This proved to be advantageous in children, since in these patients the degeneration of an aortic homograft was faster compared to an older population. This was explained by the recipient's immunologic response to the graft which was more pronounced in younger patients. The advantages of homografts with regards to hemodynamics and thromboembolic risk make them a good alternative to mechanical prostheses in younger, active patients. In very young patients, a Ross-procedure was shown to be superior to aortic homografts due to slower degeneration of the autograft. The decision to use a homograft must be made individually according to the patients demands.

Heart Diseases↗
PubMed2002

Is there an advantage in using homografts in patients with acute infective endocarditis of the aortic valve?

BACKGROUND AND AIM OF THE STUDY: Acute infective endocarditis is a surgical challenge, particularly when paravalvular abscesses and annular destruction are present. The choice of a homograft or mechanical valve prosthesis is an important issue in these patients. The study aim was to compare the outcome with homografts and mechanical valves in patients with acute infective endocarditis. METHODS: A total of 77 patients (mean age 49+/-9 years) operated on for acute endocarditis of the aortic valve was included in the study and analyzed retrospectively. The causative bacterium was isolated from blood cultures in 71 cases. Preoperatively, 21 patients required artificial ventilation and 24 had inotropic support due to hemodynamic instability. Aortic homografts were implanted in 43 patients, and mechanical valve prostheses in 34. The two patient groups were similar in terms of gender, age and preoperative inotropic support. In total, 31 patients (44%) had paravalvular abscesses, and a homograft was used significantly more often (77%, p <0.05) in these cases. Follow up examinations (clinical examination, ECG and transthoracic echocardiography) were performed six months postoperatively and continued on an annual basis. Endocarditis relapse was defined as persisting infection, whereas re-endocarditis indicated a new infection after an interval of at least six months. RESULTS: Perioperative mortality was 11.5% (5/43) in homograft patients. In the 38 survivors, follow up was complete and averaged 5.0+/-1.2 years. One patient had an endocarditis relapse three months after surgery. Re-endocarditis occurred in three patients after two or three years. One other patient had pseudoaneurysm formation without a need for intervention, and one had repeat aortic valve replacement due to dysfunction of the graft after four years. The other 33 patients had an uneventful follow up. Echocardiography revealed aortic insufficiency grade 1 in 12 cases (36%), with no progression during follow up. Perioperative mortality in mechanicat valve patients was 20.5% (n = 7) (p <0.05 versus homograft), and in those with paravalvular abscess, perioperative mortality was even higher than in homograft patients (4/7, 57.1% versus 3/24, 12.5%; p <0.05). When considering only patients without paravalvular abscess, there was no significant difference between groups (10.5% versus 12.5%). Three relapses occurred in mechanical valve patients (10.3%), but no endocarditis recurred during follow up. One late death (3.7%) occurred due to bleeding complicating long-term anticoagulation. CONCLUSION: The study results do not permit a general recommendation to be made for homograft use in patients with acute endocarditis. In cases with paravalvular abscesses, however, there was a trend towards improved outcome in the homograft group.

Adult↗
PubMed2002

Myoblasts survive intracardiac transfer and divide further after transplantation.

OBJECTIVE: Skeletal myoblasts have been proven to survive transplantation into myocardial scar tissue. The objective of this study was to evaluate whether these cells can also be transferred into vital myocardium and maintain their ability for cell division after transplantation. In addition, an intravital fluorescence dye for marking these cells was evaluated. MATERIAL AND METHODS: Skeletal myoblasts were harvested from male Lewis rats (n = 6) and then expanded in culture. Before implantation, these cells were trypsinized and labeled using an intravital fluorescence dye (PKH-26). Syngenic myoblast transfer to recipient female Lewis rats (n = 36) was used to simulate autologous transplantation. Under general anesthesia, the rats received injections of 106 myoblasts via a subxyphoidal approach into the apex of the heart. The animals were then divided into 3 groups (n = 10 each). The animals were sacrificed at several time points, and the hearts were harvested for histologic examination: group A, 7 days postoperatively; group B, 14 days postoperatively; and group C, 28 days postoperatively. An additional group, group D (n = 6), served as a control group; these animals were injected with only cell medium. Corresponding to the study groups, 2 animals of this control group were sacrificed at each time point, and the hearts were explanted. At histological examination, 8- m sections were investigated to identify surviving stained cells. For further evaluation, the sections were stained using monoclonal antibodies against n-cam, desmin, and a- actin. RESULTS: No fluorescing cells were found in any hearts of rats in the control group. Surviving fluorescing myoblasts were found in 9 of 10 hearts of groups A and C and 8 of 10 hearts of group B. Labeled myoblasts were located in the intercellular spaces between the myocardial fibers. Fibrotic or inflammatory reactions could not be identified around the injection site in any hearts of the study groups. Immunohistochemical staining results showed that the labeled cells expressed n-cam, desmin, and a-actin. The myoblasts had regained their physiologic structures and had started to form myofibers. In groups B and C, more n-cam-positive cells than labeled cells were found, indicating further cell division. CONCLUSIONS: Intravital fluorescence staining with PKH- 26 dye proved to be an easy and reliable method for identifying cells after cellular transplantation. Myoblasts survived an intracardiac transfer, regaining their physiologic structures and maintaining their ability for further cell division.

Animals↗
PubMed2002

Cell transplantation--a potential therapy for cardiac repair in the future?

PURPOSE: Adult human myocardium cannot regenerate because cardiac muscle cells do not reenter the cell cycle. Myoblasts, cardiomyocytes, and stem cell-derived cardiomyocytes have been transplanted in experimental settings to replace lost myocardial tissue. The purpose of this paper is to review the experimental data about cell transfer onto myocardium and to highlight the advantages of the particular cell types used. BACKGROUND AND METHODS: Myoblasts or satellite cells are precursor cells attached to skeletal muscle fibers. The transfer of these cells onto damaged myocardium was demonstrated successfully in several animal models. Because myoblasts can be expanded in culture, a large number of cells can be obtained from only a small skeletal muscle specimen. These cells could be delivered locally by injection within a damaged myocardial area or by coronary infusion. However, only one group has been able to show an improvement in myocardial function after myoblast transfer. The second type of cells used experimentally for cell transfer were fetal cardiomyocytes. Fetal cardiomyocytes retain the ability to divide and therefore can be expanded in culture. The cells were integrated into the myocardial tissue, differentiated into normal cardiac muscle cells, and formed intercellular connections with host myocardial cells. The transplantation of these cells onto cryo-injured myocardium resulted in improved cardiac function in several animal models. Stem cell-derived cardiomyocytes can be selected from embryonic stem cells. These cells still divide and differentiate into different cardiac muscle cells (atrial, ventricular, and pacemaker). After transplantation into damaged myocardium in mice, they formed stable grafts and survived for at least 7 weeks. The selection of these cells has to be performed with care to prevent teratoma formation originating from single undifferentiated cells attached to the transferred cells. Recent experimental studies revealed the ability of bone marrow stem cells to differentiate into cardiomyocytes. These cells were transplanted into damaged myocardium via coronary perfusion. They survived for at least 4 weeks and showed differentiation toward cardiac muscle cells. The functional benefit of bone marrow stem cells, however, has not been clearly demonstrated, and there is a possibility of tumor formations originating from these cells. DISCUSSION: Myoblasts and bone marrow stem cell-derived cardiomyocytes would permit autologous cell transfer onto the myocardium. These cells can be easily obtained and expanded in culture. Gene transfer is also possible, and there are no ethical proscriptions against an autologous cell transfer. However, the integration and final differentiation of these cells in the heart tissue is not clear yet. Fetal cardiomyocytes, on the other hand, are integrated in the myocardial tissue, improve cardiac function, and can be expanded in culture. Their transfer would be allogenic, making immunosuppression necessary. Stem cell-derived cardiomyocytes could be used to replace all 3 types of cardiac muscle cells, and they can be expanded in culture. The possibility of teratoma formation makes a 100%- selection mandatory. At present, ethical concerns against working with human embryonic stem cells are a factor to be considered. CONCLUSIONS: Cell transfer therapy has been shown to improve myocardial function in animal experiments. This finding indicates that a reduced myocardial function can be improved by cell transfer therapy. Stem cell-derived cardiomyocytes in particular, either of embryonic or bone marrow cell origin, would allow for selective replacement of pacemaker cells or atrial or ventricular cardiomyocytes.

Heart Diseases↗
PubMedDate not supplied

Mechanical circulatory support in pediatric patients with the MEDOS assist device.

Mechanical circulatory support is successfully applied to patients with low cardiac output. The MEDOS-System provides pulsatile ventricular assistance for patients of all age groups, including neonates. We report our experience with seven consecutive pediatric patients with the MEDOS-VAD. The indication was bridge to transplantation in all patients. Mean age was 7.3 +/- 6.5 years (range 0.75-16.9 years) and mean weight was 26.3 +/- 21.7 kg (range 5.9-60 kg). Perioperative survival was 100%; complications occurred in six patients (86%; two cerebral embolism/bleeding, two rethoracotomy, two exchange of pump chamber due to thrombus formation after 4 and 9 days). Mean duration of support was 20.4 +/- 10.8 days (range 6-38 days). Bilirubin decreased from 3.5 +/- 2.6 mg/d to 2.1 +/- 1.2 mg/d. Hospital mortality was three of seven patients who did not receive an organ offer in time. All patients who underwent subsequent heart transplantation (four of seven patients; 57%) were discharged from the hospital. Mechanical circulatory support with the MEDOS-System can be performed successfully in pediatric patients of any age. Secondary organ functions improve under this pulsatile circulatory assistance. Hemorrhage and thromboembolic events are the most frequent complications.

Adolescent↗