Biomedical subjects

Hermann Reichenspurner

Publications and source records attributed to Hermann Reichenspurner.

16 recordsLinked to original sources

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

New technique for chest opening in mice: U-sternotomy.

In cardiac xenotransplantation, transfections with recombinant adeno-associated viruses could be a promising way of modulating the cardiomyocyte genome. Proteins like TRAIL, hDAF, Il-10, Il-4, and beta-galactosidase may be expressed on cardiomyocyte surfaces in order to prevent cellular rejection processes. However, after intracoronary perfusion with transfecting viruses, it takes up to 4 weeks before expression of the transgene can be detected. Mouse models have been established to create reliable transfection protocols. Currently, the major problem involves performing the intraaortic injection in mice without causing a lethal pneumothorax. Here we describe a new technique for chest opening to safely reach the mouse ascending aorta without opening the pleural space. This U-sternotomy reduces the risk of animal death and therefore the amount of quite expensive virus solutions needed.

Animals↗

PubMed2003

Cyclosporine A versus tacrolimus in combination with mycophenolate mofetil and steroids as primary immunosuppression after lung transplantation: one-year results of a 2-center prospective randomized trial.

OBJECTIVES: Cyclosporine (INN: ciclosporin) A or tacrolimus have been used mostly in combination with azathioprine as primary immunosuppression after lung transplantation. Benefit or risk deriving from the combination with mycophenolate mofetil are yet unknown. METHODS: In a prospective, 2-center, open randomized trial, the combination of cyclosporine A, mycophenolate mofetil, and steroids was compared with tacrolimus, mycophenolate mofetil, and steroids as primary therapy after primary lung transplantation. All patients underwent induction therapy with rabbit antithymocyte globulin for 3 days. The 2 groups were compared with regard to patient survival, freedom from acute rejection, bronchiolitis obliterans, infectious episodes, and side effects. RESULTS: Between September 1997 and April 1999, 74 lung transplant recipients were randomized to receive either cyclosporine A (n = 37) or tacrolimus (n = 37). Groups were comparable with regard to age, sex, transplant procedure, and cytomegalovirus match. Mean follow-up was 507 +/- 258 and 508 +/- 248 days, respectively. Six- and 12-month survival was similar in both groups (89% vs 84% and 82% vs 71%, respectively; P =.748 at 12 months). Two patients from the cyclosporine A group were retransplanted. Freedom from acute rejection at 6 and 12 months was comparable between groups (46% vs 51% and 35% vs 46%, respectively; P =.774 at 12 months). The mean number of treated acute rejection episodes per 100 patient-days was higher in the cyclosporine A than in the tacrolimus group, but the difference was not statistically significant (0.32 +/- 0.42 vs 0.22 +/- 0.30, respectively; P =.097). Four patients from the cyclosporine A group had to be switched to tacrolimus to control ongoing rejection, whereas no patient from the tacrolimus group had to be switched to cyclosporine A. There was a trend toward more infections (0.7 +/- 0.36 vs 0.55 +/- 0.31, P =.059) in the cyclosporine A group. New-onset diabetes mellitus was observed in the tacrolimus group only (11% vs 0%, P =.151), whereas there was a higher incidence of hypertension (60% vs 11%, P =.03) in the cyclosporine A group. CONCLUSION: This 2-center, prospective randomized study showed high immunosuppressive potency of both cyclosporine A and tacrolimus in combination with mycophenolate mofetil. No significant difference in incidence of acute rejection was observed between the 2 groups. Moreover, survival and incidence of infection were similar. Incidence of drug-related adverse events were similar, yet their spectrum was different.

Acute Disease↗

PubMed2003

Early and midterm results after coronary artery bypass grafting with and without cardiopulmonary bypass: which patient population benefits the most?

BACKGROUND: We present our early and midterm results with off-pump coronary artery bypass grafting (OPCAB) on the beating heart and with conventional coronary artery bypass grafting (CABG) and compare patient outcomes for both procedures. METHODS: Between November 1997 and April 2001, OPCAB was performed in 330 patients. The results were compared with those of a matched population of 330 patients who had undergone CABG during the same period. Specific postoperative outcomes were evaluated for patient subgroups with multimorbidity, with impaired ventricular function, of an older age, and of a young age without comorbidities. Midterm results and quality-of-life (QOL) scores for patients were obtained by follow-up. RESULTS: In the overall series, OPCAB resulted in signifi- cantly shorter surgery times (P =.008), ventilation times (P <.001), intensive care unit (ICU) stays (P <.001), and hospital stays (P =.006). OPCAB also resulted in less postoperative inotropic medication (P =.041), lower transfusion rates (P <.001), fewer postoperative myocardial infarctions (P =.038), and lower hospital mortality rates (P =.024). Among the patient subgroups, patients with multimorbidities were the only subgroup to show a significant reduction in hospital mortality after OPCAB surgery (P =.048). Times of postoperative ventilation, ICU stay, and hospitalization were significantly reduced for all patient subgroups (P <.05). After mean followup times of 43.8 months (OPCAB) and 44.8 months (CABG), QOL scores, midterm complication rates, and mortality rates were not significantly different among the groups. CONCLUSION: OPCAB surgery improved postoperative recovery for the entire patient population without compromising midterm outcome. Compared with conventional CABG, high-risk patients with multimorbidity particularly profit from avoiding cardiopulmonary bypass and show significantly lower hospital mortality.

Aged↗

PubMed2003

Robotically assisted coronary artery bypass surgery with the ZEUS telemanipulator system.

Our goal of minimally invasive coronary bypass surgery is a completely endoscopic operation and anastomosis. Minimally invasive procedures reduce the invasiveness of the operation and therefore the morbidity and length of hospitalization of the patients. A possible solution to the technical problems that accompany manually performed endoscopic anastomoses is telemanipulation, which provides surgeons with the necessary equipment to accomplish totally endoscopic coronary anastomoses. Robotic telemetric systems together with 3-D visualization provide the necessary platform. This article summarizes the current worldwide experience with the ZEUS(TM) system in cardiac surgery and describes the steps from preclinical to endoscopic operation, focusing on the potential limitations of the procedure and the system.

Anastomosis, Surgical↗

PubMed2003

Ventricular reshaping with devices.

Device-based left ventricular reshaping to facilitate reverse remodeling in cases of congestive heart failure represents an innovative surgical strategy. Originating from experiences gained with partial left ventriculectomy and dynamic cardiomyoplasty, the Myocor Myosplint device and the Acorn CorCap Cardiac Support Device are intended to improve left ventricle function through left ventricular shape change by means of wall stress reduction and passive diastolic support, respectively. Encouraging experimental and early clinical results with both devices support these novel concepts. Careful patient selection and a combined approach integrating adjunct surgical and medical treatments are crucial factors for the success of ventricular reshaping.

Animals↗

PubMed2002

Stent-based approach for ventricle-to-coronary artery bypass.

BACKGROUND: Ventricle-to-coronary artery bypass (VCAB) is an experimental revascularization procedure that provides predominantly systolic instead of diastolic blood flow to a coronary artery. METHODS AND RESULTS: In a pig model, a stent-based procedure (VSTENT) was developed to create a VCAB. After thoracotomy, a covered VSTENT was implanted between the left ventricle and the left anterior descending coronary artery (LAD). Distal LAD flow, regional myocardial function, and intracoronary pressures were determined at different degrees of LAD stenosis and during complete LAD occlusion. During 3 hours of LAD occlusion, VSTENT preserved net forward flow at 70+/-6% and regional myocardial function at 71+/-8% of baseline. Preservation of net flow was influenced by the positioning of the VSTENT, with higher preservation also under conditions of increased oxygen demand if a "valve-like mechanism" was present during diastole. At a hemodynamically relevant level of LAD stenosis (>70%), systolic inflow was predominant after VSTENT implantation. Changes in mean diastolic intracoronary pressure that resulted from different degrees of LAD stenosis were linearly correlated to net flow after VSTENT implantation (r=0.88; P<0.001). CONCLUSIONS: VSTENT for ventricle-to-coronary artery bypass was feasible and preserved 70+/-6% of baseline flow during complete LAD occlusion. The degree of preservation was dependent on the position of the VSTENT creating a valve-like mechanism during diastole. Residual diastolic blood flow through a high-grade LAD stenosis influenced net flow favorably, because diastolic backflow decreased with increasing mean diastolic intracoronary pressure.

Animals↗

PubMed2002

Functional and biochemical analysis of endothelial (dys)function and NO/cGMP signaling in human blood vessels with and without nitroglycerin pretreatment.

BACKGROUND: In experimental animal models, long-term in vivo treatment with nitroglycerin (NTG) induces both endothelial dysfunction and tolerance to nitrates. However, it is still controversial whether nitrate tolerance in humans is associated with both endothelial dysfunction and impaired vascular response to nitrovasodilator-derived NO. METHODS AND RESULTS: Patients undergoing elective bypass surgery were randomized to receive 48 hours of continuous NTG infusion (NTG group) or no nitrate therapy (control group). Segments of surgically removed arteria mammaria, vena saphena, and arteria radialis not required for the bypass procedure were used to examine (1) the vascular responsiveness to NTG and the endothelium-dependent vasodilator acetylcholine; (2) the expression of the NO target, the soluble guanylyl cyclase; (3) the expression of the soluble guanylyl cyclase/cGMP effector target, the cGMP-dependent protein kinase (cGK); and (4) the cGK activity as assessed by the phosphorylation state of its vascular substrate, the vasodilator-stimulated phosphoprotein at serine(239) (P-VASP). NTG treatment caused a marked degree of nitrate tolerance in all 3 vessel types studied and a significant cross-tolerance to the endothelium-dependent vasodilator acetylcholine in A. mammaria and A. radialis. Although soluble guanylyl cyclase, cGK-I, and VASP expression levels were not modified by NTG treatment, a marked decrease of P-VASP, a surrogate parameter for in-vivo cGK-I activity, was observed. CONCLUSIONS: We conclude that long-term NTG treatment induces endothelial dysfunction and impaired vascular NO/cGMP signaling in humans, which can be monitored by measuring P-VASP levels.

Aged↗

PubMed2002

Comparison of two stabilizer concepts for off-pump coronary artery bypass grafting.

BACKGROUND: This study was designed to evaluate the efficacy of two different stabilizer concepts for off-pump coronary artery bypass grafting. METHODS: Between 2000 and 2001, 100 consecutive patients who underwent off-pump coronary artery bypass grafting were randomly assigned to two stabilization systems: the Medtronic Octopus 3 (n = 50) and the Genzyme Immobilizer (n = 50). During operation, two-dimensional cardiac surface motion was assessed by intravital microscopy using orthogonal polarization spectral imaging in 20 vessels at the anterior wall. Postoperative angiography of 47 vessels revealed anastomotic quality. RESULTS: Patient demographics were similar in both groups regarding age, sex, ejection fraction, and New York Heart Association functional class. In 7 patients the randomized Immobilizer was rejected by the surgeon for lateral or posterior wall revascularization and subsequently switched to the Octopus device. Patients received 1.8 +/- 0.7 grafts in the Octopus and 1.6 +/- 0.5 in the Immobilizer group (p = not significant). Two-dimensional cardiac surface motion was significantly less using the Immobilizer (109.7 +/- 32.4 microm versus 423.5 +/- 129.6 microm; p < 0.001). Time required for anastomosis was significantly shorter in the Immobilizer group (11.3 +/- 3.5 versus 14.9 +/- 2.4 minutes; p < 0.001). Postoperative angiography showed no vessel occlusions but two anastomotic stenoses in each group. CONCLUSIONS: Both stabilizers have been shown useful for off-pump coronary artery bypass grafting. The Immobilizer system showed better epicardial immobilization of the anterior wall resulting in shorter anastomosis times. However, because the Octopus 3 handling is more flexible and allows easier access to all vessels, it is the device of choice for posterior wall revascularization in our institution.

Aged↗

PubMed2002

Multidetector computed tomography (MDCT) in coronary surgery: first experiences with a new tool for diagnosis of coronary artery disease.

BACKGROUND: Selective coronary angiography (SCA) is the standard invasive procedure for diagnosis in patients eligible for coronary artery bypass grafting (CABG). A recently developed, highly sensitive multidetector computed tomography (MDCT) scan holds promise to be of almost comparable quality and predictiveness. We examined a blinded series of preoperative patients who were admitted to hospital for conventional and minimally invasive CABG procedures. Patients underwent CT scans in addition to SCA; findings were compared regarding location and degree of coronary artery stenosis. METHODS: Twenty patients underwent electrocardiogram-gated helical CT scanning. Images with 250 ms effective exposure time were reconstructed with retrospective electrocardiogram gating. Location and degree of coronary stenoses were described and compared with findings of SCA. The study was limited to patients with a heart rate of less than 70 beats per minute and who had the ability to hold their breath for 20 to 30 seconds. RESULTS: Coronary arteries were clearly displayed by MDCT. Compared with SCA, sensitivity was 92%, specificity 84%, and negative predicted value 89% for significant stenosis (more than 50%). Early forms of atherosclerotic changes were even clearer on MDCT. In addition, the CT examination allowed differentiation of calcified and fatty or fibrous stenoses. CONCLUSIONS: Multidetector CT scanning is an effective noninvasive technique for the diagnosis of coronary artery disease. In selected patients, MDCT scanning might be able to replace SCA as a preoperative test for CABG procedures. The intrathoracic situs can be clearly exposed as it is important for the planning of minimally invasive CABG procedures.

Coronary Angiography↗

PubMed2002

Myosplint implant and shape-change procedure: intra- and peri-operative safety and feasibility.

BACKGROUND: In patients with dilated cardiomyopathy (DCM), the heart enlarges, leading to a corresponding increase in ventricular wall stress. To reduce the stress, transventricular tension members (Myosplint, Myocor, Inc.) were implanted to change the left ventricle (LV) effective radius and to reduce the LV wall stress by 20%. We conducted this study to evaluate the intra- and peri-operative safety and feasibility of LV-shape change therapy. METHODS: In 7 patients, all diagnosed with DCM, Myosplints were implanted. New York Heart Association class ranged from III-IV, and LV end-diastolic diameter ranged from 70 to 102 mm. Mitral valve regurgitation was classified as mild in 3 and moderate in 4 cases. Four patients underwent mitral valve annuloplasty. RESULTS: We observed no significant device-related complications, such as thromboembolism, bleeding, device instability, or vascular damage, at 90 days. Early indications in a small patient population demonstrate some improvements in clinical parameters. CONCLUSIONS: From this initial experience, one may conclude that placement of the Myosplint devices can be safely performed without early, significant adverse events. In patients with significant mitral valve incompetence, concomitant mitral valve repair is indicated to realize the full benefit of the procedure. This study also suggests that Myosplints can be safely implanted in combination with mitral valve repair. The long-term effect of each procedure on cardiac function and survival will require further evaluation.

Adult↗

PubMed2002

Heart transplantation: an approach to treating primary cardiac sarcoma?

Treating rare, primary cardiac soft-tissue sarcomas (C-STS) with heart transplantation (HTx) is controversial. Conventional tumor resection only partially alleviates the disease, and patients die of local recurrence of the tumor or of distant metastases. Heart transplantation offers the opportunity to eradicate the primary malignancy completely. In our experience of 4 patients with C-STS indicates, HTx followed by post-operative chemotherapy does not affect the long-term outcome. However, pre-operative chemotherapy can regress tumors in chemosensitive C-STS and potentially eradicate early micrometastases. Consecutive HTx for responders may then offer a chance of long-term survival.

Adult↗

PubMed2002

Evaluation of acute traumatic changes of the coronary artery wall after robotically assisted endoscopic coronary artery bypass grafting.

BACKGROUND: There is concern that the technical limitations of robotic systems used in endoscopic coronary artery bypass grafting (CABG) may lead to increased trauma of the anastomotic site. To examine this issue, we compared the acute traumatic changes of the coronary artery wall caused by conventional manual suturing and robotically assisted suturing for anastomoses using the ZEUS telemanipulator (Computer Motion Inc., Goleta, CA) in a laboratory setting. METHODS: Coronary artery bypass grafting was performed on isolated porcine hearts. Fifteen anastomoses (with harvested porcine right coronary artery (RCA) segments) were carried out using the ZEUS microsurgical telemanipulator (group Z), while 15 further anastomoses were performed with a conventional manual technique (group M) using Gore-Tex CV-8 suture material. Specimens were taken from each anastomotic site and from native parts of the left anterior descending artery (LAD) (control group). Morphological changes of the cellular and fibrous components of the lamina intima and lamina media, and the shape and maximum diameter of the puncture mark, were examined by light microscopy (LM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Vascular endothelial damage and denudation were graded on a score from 1 to 5. RESULTS: In each group, 14 specimens were evaluated. SEM findings showed a significantly higher degree of endothelial denudation in group Z and group M compared to the control group, while group Z was significantly more affected than group M. Likewise, the maximum diameter of the puncture mark was significantly larger in group Z than in group M. TEM and LM studies supported these results. In addition, LM revealed that in five specimens of group Z the shape of the stitch through the artery wall was not cylindrical, as in the other cases, but was asymmetrical and displayed a superficial furrow on the side of the vascular lumen. CONCLUSION: The results indicate that there is an increased incidence of damage to the coronary artery wall caused by the microsurgical telemanipulator. Further studies are necessary to determine whether the differences between conventional and robotic-assisted suturing techniques will have an effect on the long-term outcome of coronary artery bypass grafting.

Anastomosis, Surgical↗

PubMed2002

Minimally invasive direct coronary artery bypass grafting (MIDCAB) and off-pump coronary artery bypass grafting (OPCAB): two techniques for beating heart surgery.

OBJECTIVE: Coronary bypass surgery can be performed less invasively by avoiding cardiopulmonary bypass (CPB). We present our experiences with beating heart bypass surgery performed through a minithoracotomy or sternotomy. METHODS: From May 1997 to September 1999, 340 patients were included in a prospective study. Of these patients, 111 (group 1) underwent minimally invasive direct coronary artery bypass grafting (MIDCAB) through an antero-lateral minithoracotomy, and 229 (group 2) had off-pump coronary artery bypass grafting (OPCAB) through a full sternotomy. A pressure stabilizer was used for MIDCAB and a suction stabilizer for OPCAB surgery. Early postoperative angiography was performed on 48% of patients in group 1 and 45% of those in group 2. Statistical analysis was applied to compare the variables from both groups and a probability value of less than 0.05 was considered significant. RESULTS: In all MIDCAB grafts, revascularization was performed by a single left internal mammary artery (LIMA) graft to the left anterior descending coronary artery (LAD). This procedure was completed in 96.4% of patients without CPB. Conversion to sternotomy was necessary for one patient (0.9%). In the OPCAB group, an average of 1.7 grafts per patient were revascularized, of which 98 were single, 99 double, and 32 triple. Of the OPCAB group, 12% of patients were redo operations and 17% had severe comorbidities. Conversion to CPB was necessary for 10 patients (4.4%) because of hemodynamic instability. No cerebrovascular accident (CVA) was seen in any group. There were no hospital deaths in the MIDCAB group, but there were three deaths (1.3%) in the OPCAB group. Age, previous bypass surgery, and severe comorbidities did not influence early mortality. Early postoperative reoperation due to graft failure was necessary for three patients (2.7%) after MIDCAB and for three patients (1.3%) after OPCAB. Confirmed by angiography, the early postoperative total graft patency rate was 96.2% in the MIDCAB group and 96.6% in the OPCAB group; the perfect patency rate (no stenosis greater than 50%) was 92.4% and 93.1%, respectively. CONCLUSIONS: Coronary bypass surgery without the use of CPB is feasible and safe, and offers good early results. Nevertheless, MIDCAB grafting is a challenging technique and should only be performed in selected patients with favorable coronary anatomy. On the other hand, with the sternotomy approach, exposure of all vessels was well tolerated and made complete revascularization feasible. OPCAB can be performed safely even on high-risk patients.

Cardiopulmonary Bypass↗

PubMed2002

Robotically-assisted coronary artery surgery with and without cardiopulmonary bypass - from first clinical use to endoscopic operation.

BACKGROUND: Recently, the ZEUS(tm) Robotic Surgical System has been introduced to increase the precision of endoscopic cardiac surgery. This study investigated its clinical use for endoscopic coronary artery bypass grafting. MATERIAL/METHODS: Between 1998 and 2001, 41 patients with single and multivessel disease were operated on using the ZEUS(tm) system. The robotic system was introduced step by step into clinical practice. Initially, the system was used only for endoscopic internal mammary artery (IMA) harvest (n=12), later for coronary anastomoses on the arrested (n=13) or beating heart after median sternotomy (n=6), and finally for endoscopic coronary bypass grafting on either the arrested (n=2) or beating heart (n=8). RESULTS: Endoscopic IMA harvest ranged from 48 to 110 min and was completed in all cases. In the sternotomy group, the robotic anastomosis time averaged 21 min on the arrested and 25 min on the beating heart, respectively (n.s.). In the endoscopic cases, the average time for endoscopic anastomosis was 41 min on the arrested and 36.5 min on the beating heart (n.s.), with an overall duration of surgery between 4.0 and 8.0 hours. One endoscopic case was intraoperatively converted to a MIDCAB procedure with manual anastomosis. The total patency rate of all graft anastomoses, confirmed by early postoperative angiographic control, was 97%. One patient underwent reoperation with an uneventful postoperative course. CONCLUSIONS: The present study demonstrates the feasibility of endoscopic coronary revascularization using a computer-assisted surgical robotic system on the arrested and beating heart in selected patients.

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↗