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Background: Bonewax is routinely used to seal sternal edges after median sternotomy. Adverse effects on sternal healing, however, have been proclaimed although clear evidence does not exist. We performed a study on coronary bypass patients with or without bonewax application to verify negative effects and risk factors for early rethoracotomy, wound healing problems, and mediastinitis., Methods: In a prospectively randomized study on 400 patients undergoing isolated coronary bypass surgery, 200 patients with (bonewax) and 200 patients without bonewax (nonwax) application after median sternotomy were compared. Blood product consumption, early rethoracotomy, sternum stabilization, mediastinitis, and early mortality were compared. Risk factors such as age, sex, diabetes mellitus, and bonewax were analyzed by means of logistical regression analysis., Results: Blood product consumption was almost identical in both groups (red blood cells, 3.9 +/- 4.7 units in the bonewax group; 3.8 +/- 3.4 units in the nonwax patients; fresh frozen plasma, 0.5 +/- 1.6 units versus 0.5 +/- 1.3 units; platelet concentrates, 0.07 +/- 0.3 units versus 0.04 +/- 0.2 units). Early rethoracotomy (bonewax 6.5%; nonwax 5%), sternal stabilization (bonewax 3%; nonwax 3%), and mediastinitis (bonewax 1%; nonwax 0.5%) did not differ significantly. Early mortality was 2.5% in the bonewax group and 0.5% in the nonwax cohort. Bonewax did not appear as an independent risk factor for adverse outcome., Conclusions: Negative effects of bonewax on the percentage of postoperative complications and outcome were not shown. However, positive effects such as a reduction of blood product substitution were also not observed. Using bonewax on sternal edges is obviously safe but not particularly beneficial.

To effectively perform an anastomosis on a coronary artery under beating heart conditions, the anastomotic site must be cleared of blood to allow visualization for accurate suturing. We describe a simple, cost effective, on-site assembled blower-mister system.

The first case of a fracture of a semi-rigid annuloplasty device is reported. A 56-year-old man presented with recurrence of severe mitral and tricuspid regurgitation 10 months after proper implantation of a Colvin-Galloway Future band (Medtronic Inc, Minneapolis, MN). During redo surgery we made the unexpected finding that its metal skeleton was fractured near the posterior segment. A tear in the anterior mitral leaflet was also found. It is speculated that the device fracture may have put additional strain on the native annulus.

Restitution strategies of the insufficient aortic valve belong to the clinical armamentarium. To date, the accumulated body of evidence comprises 126 articles dealing with restitution strategies on the insufficient aortic valve with concomitant aortic surgery. In a cumulative analysis an almost identical number of reimplantation (506) and remodeling (489) procedures were found in the literature, whereas 357 patients underwent aortic valve resuspension. The cumulative results tend to favor the reimplantation technique in terms of longevity of the reconstruction, particularly in congenital degenerative disorders of the aortic wall, whereas remodeling appears to exhibit a more physiologic behavior of the reconstructed valve and re-suspension serves as a simplified approach particularly in acute type A dissection. Although restitution of the native aortic valve has its place in current treatment options, the accumulated worldwide numbers indicate that it is not yet routinely implemented in the vast majority of cardiac institutions.

Background: The optimal closure technique of median sternotomy remains controversial. The objective of this study was to analyze the structural response of the separated sternum using computer-based numerical discretization techniques, such as finite element methods., Methods: Thoracic computer tomographic scans (2.5-mm slices) were segmented, analyzed by image processing techniques, and transferred into a three-dimensional finite element model. In a first approach a linear elastic material model was used; neglecting nonlinear and damage effects of the bones. The influence of muscles and tendons was disregarded. Nonlinear contact conditions were applied between the two sternal parts and between fixation wires and sternum. The structural response of this model was investigated under normal breathing and asymmetric leaning on one side of the chest. Displacement and stress response of the segmented sternum were compared regarding two different closure techniques (single loop, figure-of-eight)., Results: The obtained results revealed that for the normal breathing load case the single loop technique is capable of clamping the sternum sufficiently, assuming that the wires are prestressed. For asymmetric loading conditions, such as leaning on one side of the chest, the figure-of-eight loop can substantially reduce the relative longitudinal displacement between the two parts compared with the single loop., Conclusions: The application of numerical simulation techniques using complex computer models enabled the determination of structural behavior of the chest regarding the influence of different closure techniques. They allowed easy and fast modifications and therefore, in contrast to a real physical model, in-depth parameter studies.

Background: Temporary intraluminal shunts (TILS) are routinely used in off-pump revascularization to facilitate the anastomosis while maintaining myocardial blood supply. Whereas tourniquet-occlusion can cause vessel wall trauma, potentially adverse chronic effects of TILS on the coronary intima have not been evaluated yet. This chronic large animal study investigated ultrastructural effects of TILS on the vessel wall., Methods: Four groups of acute and chronic pigs with either tourniquet-occlusion (TOUR) or TILS (40 kg; acute, n = 12; chronic, n = 20) were analyzed. Animals underwent median sternotomy, heparin (150 U/kg) administration, and left anterior descending coronary artery exposure. In groups with TOUR the left anterior descending coronary artery was temporarily occluded (10 minutes) with a tourniquet. In groups with TILS a silicone shunt (1.5 mm diameter, 12 mm length) was placed in the left anterior descending coronary artery more than 10 minutes and then removed, and the insertion was repaired. Thirty minutes after reperfusion all acute animals were sacrificed whereas chronic animals were extubated, maintained for 3 months, and then sacrificed. The left anterior descending coronary artery regions of occlusion or placement of the TILS silicone bulbs were examined histopathologically by scanning and transmission electron microscopy by a blinded pathologist., Results: In both acute and chronic investigations animals in the TILS group exhibited significantly less morphologic damage than animals in the TOUR group. In the acute phase significantly more loss of cell junction (p = 0.037), loss of endothelium (p = 0.032), and intimal edema (p = 0.037) in the TOUR group than in the TILS group was observed. Three months later, characteristic features with a changed pattern were detected: vacuolization of the cell (p = 0.03), loss of cell junction (p = 0.042), and removal of basal membrane (p = 0.046) as well as extensive loss of endothelium (p = 0.003) in the TOUR group compared with the TILS group., Conclusions: Intimal lesions occur with both maneuvers early and late. However, animals in the TOUR group exhibited injuries significantly more often and more severely. Therefore, acute and chronic intimal integrity of the coronary vessel may be better preserved using TILS and may thus have a positive impact on the extent of de novo stenosis and long-term prognosis of the revascularized region.

Background: Mechanical bileaflet valves with enhanced inner diameter may offer superior hemodynamic properties in patients with a small aortic annulus. The aim of this clinical study was to compare these valves with standard bileaflet prostheses in vivo., Methods: Mechanical aortic valve replacement for combined stenosis and regurgitation was performed in 47 patients with standard CarboMedics prostheses (CM: 21 mm, 23 mm, 25 mm) and two types of diameter enhanced St. Jude Medical prostheses (SJM-AHPJ: 21 mm, 23 mm, 25 mm; SJM-Regent: 21 mm, 23 mm). Transvalvular mean gradients (TVG) were assessed intraoperatively by means of transesophageal echocardiography (TVG(TEE)) and simultaneous direct pressure monitoring of the left ventricle and the ascending aorta (TVG(CATH)), as well as early (3 months) and late (9 months) postoperatively by means of transthoracic echocardiography (TVG(TTE)). Left ventricular muscle mass was assessed preoperatively, early, and late postoperatively to evaluate remodeling capacity., Results: In all valve types and sizes, both TVG assessments exhibited consistent findings. Small-sized conventional valves of 21 mm showed a marked initial TVG. In contrast, both valve types with enhanced inner diameter exhibited significantly lower TVG comparable with those achieved with larger valves (TVG(CATH) CM 21 mm, 15.6 +/- 3.9 mm Hg; SJM-AHPJ 21 mm, 11.9 +/- 1.6 mm Hg; SJM-Regent 21 mm, 9.9 +/- 1.1 mm Hg; CM 23 mm, 7.8 +/- 0.8 mm Hg; SJM-AHPJ 23 mm, 7.7 +/- 1.4 mm Hg; SJM-Regent 23 mm, 9.5 +/- 1.8 mm Hg). During the postoperative course TVG remained constant in all valve types and sizes. Left ventricular muscle mass, however, diminished markedly in all valves without exhibiting significant differences between size matched valve types., Conclusions: In patients with a small aortic annulus, who require a 21-mm valve, diameter-enhanced prostheses provide lower transvalvular gradients than conventional valves. However, in the intermediate clinical course, appropriate left ventricular remodeling occurred in all patients independent of the size and the type of the valve.

Reconstruction of the aortic valve and replacement of the ascending aorta instead of use of a composite graft is the preferred method in patients, who demonstrate an ascending aneurysm accompanied by aortic root enlargement and aortic valve insufficiency with morphologically intact cusps. Two techniques inaugurated by David and Yacoub have gained widespread acceptance. However, both approaches are technically demanding. We present a simplified alternative technique for aortic valve reconstruction by means of a reduction plasty of the aortic root without the necessity of transection maneuvers.

Background: Indication for immediate revascularization during acute myocardial infarction (MI) is debated. Drug-resistant crescendo angina, as well as hemodynamic compromise, however, often requires acute operation. In this study the differential risks of acute coronary artery bypass grafting with and without MI were stratified., Methods: Five hundred eighteen patients undergoing isolated coronary artery bypass grafting were investigated. Thirty-nine patients underwent acute revascularization because of enzyme-proven or electrocardiogram-proven MI accompanied by crescendo angina, hemodynamic compromise, or both. They were compared with 33 emergent, 63 urgent, and 383 elective patients without MI. Preoperative risk factors for early mortality and necessity of continuous venovenous hemofiltration were analyzed by means of logistical regression analysis. Perioperative data were compared., Results: Early mortality of the MI cohort was 15.4%, in contrast to 15.2% in emergent, none in urgent, and 2.1% in elective patients. Left internal thoracic artery was used in 87% of MI, 97% of emergent, 94% of urgent, and 97% of elective patients. Intraaortic balloon pump was necessary in 50% of MI patients, 27% of emergent, 6.3% of urgent, and 3.1% of elective cases. Continuous venovenous hemofiltration was performed in 29% of MI patients, 15% of emergent, 4.9% of urgent, and 3.4% of elective patients. Hemodynamic instability significantly increased the odds ratio for early mortality and continuous venovenous hemofiltration., Conclusions: Patients undergoing acute revascularization carried an elevated risk to die early notwithstanding the presence or absence of acute MI. Liberal use of left internal thoracic artery grafts was not detrimental in acute patients whereas liberal use of intraaortic balloon pump was beneficial. In almost 30% of MI patients, continuous venovenous hemofiltration was not necessary, implying a severely impaired perioperative hemodynamic condition. Immediate revascularization in the presence of acute MI is therefore indicated although it may be addressed as a separate high-risk group.

Background: Minimally invasive direct coronary artery bypass is an established clinical procedure for revascularization of the left anterior descending coronary artery. Mechanical stabilization and temporary occlusion is currently used to perform the anastomosis of the internal thoracic artery to the left anterior descending coronary artery. However, critical reduction of cardiac function can occur as a result of temporary ischemia. The purpose of this study was to evaluate whether ischemic sequelae can be avoided by using temporary intraluminal shunts and whether this alters early outcome., Methods: Thirty-five patients underwent minimally invasive direct coronary artery bypass revascularization using a mechanical stabilizer. In group A (n = 20), the anastomotic site was temporarily occluded by tourniquets. In group B (n = 15), temporary intraluminal shunts were inserted into the anastomotic site without any occlusion of the left anterior descending coronary artery. Anastomosis of the internal thoracic artery to the left anterior descending coronary artery was performed in an identical fashion. A Swan-Ganz catheter was inserted, and transesophageal echocardiographic measurements were obtained for analysis of left ventricular (LV) function. Regional wall motion, cardiac index, stroke volume index, systolic and diastolic LV diameters, and fractional area change were measured during four periods: at the start of the operation (baseline), placement of the stabilizer (stabilization), left anterior descending coronary artery occlusion (occlusion) or insertion of temporary intraluminal shunts (shunt), and 30 minutes after reperfusion (reperfusion). Angiograms were obtained 4 to 6 days postoperatively., Results: In group A, LV performance, cardiac index, stroke volume index, and fractional area change decreased during occlusion whereas systolic diameters increased. Almost two myocardial segments per patient developed severe hypokinesia in the perfusion area. These changes disappeared after 30 minutes of reperfusion, with increased LV function. In group B, LV function remained stable whereas hypokinetic wall motion was only detected in 2 patients. Early angiograms revealed 90% of the grafts were patent in group A versus 100% in group B. The need for percutaneous intervention during the first 6 months was 20% in group A versus 6.7% in group B., Conclusions: The use of temporary intraluminal shunts resulted in reduced acute ischemia and revealed wall motion abnormalities and maintained LV function. Furthermore, this technique suggests an improvement of early graft patency and a lower reintervention rate within the first 6 postoperative months. Thus, use of temporary intraluminal shunts appears to be superior to the occlusion technique early after minimally invasive direct coronary artery bypass procedures.

Objective: The therapeutic strategy in non-small-cell lung cancer (NSCLC) requires exact staging of tumour invasion (T) as well as differentiation between ipsi- and contralateral lymph node invasion (N1/2 vs N3). [18F]FDG-positron emission tomography (FDG-PET) has been shown to detect invaded N with high accuracy while correct determination of T appears to be unclear. The purpose of this prospective study was to evaluate benefit and necessity of 18FDG-PET as an additive to conventional staging modalities., Methods: Forty patients with suspected non-small-cell lung cancer (NSCLC) were staged by means of computed tomography (CT), bronchoscopy, mediastinoscopy and bone scintigraphy. Additionally, attenuation corrected FDG-PET of the thorax was performed pre-operatively for analysis of T and N topography. After surgical resection with radical lymphadenectomy T and N staging results of CT and PET were compared with the pathological diagnoses. Specificity, sensitivity, positive predictive value and accuracy of CT and PET were calculated., Results: Twenty three squamous cell carcinomas, 14 adenocarcinomas, and three non-malignant tumours were found. Accuracy of CT-T was 0.75 and of PET-T 0.78; accuracy of CT-N was 0.78 and of PET-N 0.80. By combination of CT-T and PET-T accuracy was 0.88. Combination of CT-N and PET-N yielded an accuracy of 0.90. In two out of three cases, PET correctly determined T0. In two cases non-malignant inflammatory lymph nodes were falsely staged as malignant by PET., Conclusions: Adequate pre-operative T- and N-staging is possible with both CT and FDG-PET. Accuracy can be improved by combination of CT and FDG-PET. FDG-PET is superior to CT in order to differentiate between malignant and benign tumours. However, acute inflammation can mimic malignant lymph node invasion. FDG-PET is justified as a supporting staging measure in cases presenting unclear differentiation between N2 and N3 after conventional staging and is helpful in cases with unclear cell type of the primary tumour., (Copyright Harcourt Publishers Limited.)

We report the case of a 65-year-old male who developed an oropharyngeal carcinoma, an oesophageal carcinoma and two primary bronchial carcinomas in combination with a renal cell carcinoma as an additional primary entity. By means of an aggressive diagnostic regimen including radiological and nuclear imaging techniques all carcinomas were detected early and could be treated with curative intention., (Copyright 2000 Harcourt Publishers Ltd.)

Exceptionally few cases worldwide have survived weaning from a biventricular assist device following heart transplantation in contrast to those who underwent early retransplantation. We present a successful outcome after biventricular assist device implantation following initial biventricular failure after heart transplantation. Weaning could be performed after 1 week, although pulmonary vascular resistance remained markedly elevated.

Background: We previously demonstrated that the supplement of both dibutyryl cyclic adenosine monophosphate (db-cAMP) and nitroglycerin to the conventional ET-Kyoto solution improved lung preservation significantly. However, the significance of each component in lung preservation remained unclear. We examined the efficacy of the two components on lung preservation in the current study., Methods: Rat lung grafts (eight per group) were studied in an isolated lung perfusion model. Group 1 grafts were flushed and preserved with ET-Kyoto solution containing 2 mmol/L of db-cAMP. Group 2 grafts were flushed and preserved with ET-Kyoto solution containing 100 mg/L of nitroglycerin. In group 3, the grafts were flushed and preserved with ET-Kyoto solution containing neither db-cAMP nor nitroglycerin as control group. After 4-hour cold storage, the lung grafts were reperfused for 50 minutes., Results: The lung grafts in groups 1 and 2 showed significantly better lung function after reperfusion than those in group 3 with regard to arterial oxygen tension, shunt fraction, peak inspiratory airway pressure, mean pulmonary arterial pressure, and pulmonary vascular resistance. The supplementation of db-cAMP improved especially the pulmonary arterial pressure and pulmonary vascular resistance, while the supplementation of nitroglycerin improved especially the oxygenation and airway pressure of the grafts., Conclusions: Both of db-cAMP and nitroglycerin had beneficial effects on lung preservation and are essential to the ET-Kyoto solution. There was a difference between the two components in the effects on preserved lungs.

The objective of this study was to investigate the role of contrast enhancement using a three-dimensional (3D) phase-contrast (PC) magnetic resonance (MR) sequence (3D PC-MRA) and to assess the value of a dynamic MR perfusion study of the kidneys to determine the hemodynamic relevance of unilateral renal artery stenosis (RAS). Seventeen patients with unilateral RAS were examined on a standard 1.0 T imaging system using a phase shift and magnitude sensitive 3D PC sequence (TR=160 ms, TE=9 ms, venc. 30 cm/s). Following the initial pre-contrast 3D PC-MRA a dynamic first pass perfusion study was performed using a Turbo-FLASH 2D sequence (TR=4.5 ms, TE=2.2 ms, TI=400 ms) after bolus injection of 0.15 mmol gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA)/kg body weight. The 3D PC-MRA was then repeated during infusion of 0.15 mmol Gd-DTPA/kg body weight. Evaluation by three independent readers was based on maximum intensity projection images. Source images were rendered on request. Signal intensity (SI) over time curves of the renal cortex were obtained from the dynamic perfusion study and analyzed for maximum signal enhancement as well as temporal relationship to the aortic SI curve. Results from 3D PC-MRA revealed a sensitivity (pre-/post-contrast) of 100%/89%, specificity of 76%/63%, positive predictive value of 80%/69 %, negative predictive value of 90%/78%, and accuracy of 85%/75% (p=0.07). Interobserver agreement was kappa=0.61/kappa=0.47 (pre/post Gd-DTPA), respectively. Increased signal-to-noise was present in all segments of the renal arteries post contrast (p=0.0003). This came along with image degradation due to aliasing and elevated SI of venous flow that partially obscured the renal arteries. Dynamic SI curves showed a significantly decreased maximum SI in RAS (p=0.01-0.001). A temporal delay of cortical signal intensity enhancement could not be confirmed in this setting. Gd-enhanced 3D PC-MRA did not yield a superior diagnostic value in the diagnosis of RAS compared to pre-contrast measurements. Dynamic perfusion imaging of the kidneys, in combination with 3D PC-MRA, can contribute additional information in suspected unilateral RAS.

Background: Low-potassium solutions have been shown to improve lung preservation. The optimal potassium concentration, however, has not been investigated systematically. The purpose of this study was to evaluate the effect of solutions with different potassium concentrations on functional and structural preservation after flush-perfusion and ischemia. We used our established extracorporeal working heart-lung model and a modification of this model with isolated pulmonary perfusion at defined flow rates., Methods: In two sets of experiments 42 rat heart-lung blocks (experiment I and II: n=7/group) were used. Lungs were flush-preserved with 20 ml Euro-Collins solution (EC115; K+ 115 mmol/L), potassium-reduced Euro-Collins solution (EC40; K+ 40 mmol/L), or low-potassium Euro-Collins solution (EC10; K+ 10 mmol/L) and stored for 2 hours at 10 degrees C. Reperfusion was performed for 40 minutes with Krebs-Henseleit solution containing washed bovine red blood cells (38%) while the lungs were ventilated with room air. In experiment I pulsatile perfusion of the lungs was achieved by the working right side of the heart. In experiment II lungs were perfused at defined flow rates by a roller pump. Postischemic function was assessed by means of oxygenation capacity and pulmonary vascular resistance. The degree of structural damage to the air-blood barrier was assessed by quantitative stereologic light and electron microscopic evaluation., Results: In both experiments after 40 minutes reperfusion oxygenation capacity was significantly higher in EC40 than in EC115 and EC10, whereas pulmonary vascular resistance was significantly higher in EC115 than in EC40 and EC10. Quantitative histologic examination showed surprisingly modest damage to the endothelial side of the air-blood barrier but a considerable degree of damage to the epithelium in both experiments. The alterations in the pump-perfused isolated lung experiments exceeded those of the pulsatile perfused heart-lung experiments. The comparative analysis of the study groups revealed a minor degree of epithelial swelling and fragmentation in EC40 than in EC115 and EC10, respectively., Conclusions: The results obtained with two modifications of an extracorporeal model indicate that flush perfusion of the lung with a potassium-reduced solution results in better functional and structural preservation than flush perfusion with either high- or low-potassium solutions. The optimum may lie in the vicinity of 40 mmol/L. Further studies are necessary to verify these initial findings.

Persistent mediastinitis despite primary revision, closed irrigation therapy, and additional secondary omental plasty is a life threatening situation in cardiac surgery. We managed this rare complication in one instance by sternectomy and hemirectus plasty as well as bilateral pectoralis plasty.

Background: The addition of dextran with a molecular weight of 40,000 Dalton in pulmonary preservation solutions has proved to be beneficial. However, dextrans of other size have not yet been investigated. Therefore, it is unclear whether dextran 40,000 represents the optimal additive for lung preservation solutions., Method: In a working rat heart-lung model, lung were preserved with regular Euro-Collins solution or with Euro-Collins solution containing 5% dextran of different sizes: 40,000 Dalton molecular weight; 70,000 Dalton molecular weight; 160,000 Dalton molecular weight. After 2 hours of ischemia functional (oxygenation; pulmonary vascular resistance) and structural (wet/dry-ratio, light microscopy) data were assessed and the amount of dextran in the lung tissue was measured., Results: Lungs preserved with Euro-Collins solution 70,000 Dalton molecular weight or Euro-Collins solution 160,000 Dalton molecular weight exhibited superior functional and structural results when compared with Euro-Collins solution and Euro-Collins solution 40,000 Dalton molecular weight. Additionally, the least amount of dextran in the lung tissue was found in organs preserved with Euro-Collins solution 160,000 Dalton molecular weight after ischemia and reperfusion., Conclusions: Dextrans are useful additives for lung preservation solutions. However, the size of the molecules is important because dextrans of 160,000 Dalton molecular weight were superior to dextrans of lower molecular weight in our study.

In the present report the prevalence, severity, and risk factors of tricuspid valve regurgitation (TR) in 251 heart transplant recipients have been analyzed retrospectively. Tricuspid valve function was studied by color-flow Doppler echocardiogram and annual heart catheterization. The presence or severity of TR was graded on a scale from 0 (no TR) to 4 (severe). Additional postoperative data included rate of rejection, number of endomyocardial biopsies, incidence of transplant vasculopathy, and preoperative and postoperative hemodynamics. The incidence of grade 3 TR increases from 5% at 1 year to 50% at 4 years after transplantation. Multivariate analysis showed rate of rejection and donor heart weight to be significant risk factors. The ischemic intervals as well as the preoperative and postoperative pulmonary hemodynamics did not affect the severity or prevalence of TR. These results indicate that various factors appear to have an impact on the development of TR and that the prevalence might be lowered by a reduction of the number of biopsies performed and when possible, oversizing of donor hearts.

Background: The underlying mechanism of accelerated coronary vasculopathy in cardiac allografts still remains unclear. Our hypothesis was that inhibition of smooth muscle cell proliferation with the somatostatine analogue Angiopeptin may reduce vasculopathy., Methods: Fifty-four patients received Angiopeptin injections (1500 micrograms x three times daily subcutaneously) for 21 days after the operation and three additional injections with every rejection treatment. Angiography was performed yearly, and data were compared with a matched historic control group., Results: Actuarial survival was 85% at 1 year and 80% at 2 years, comparable with our results in general (80%/77%). Forty-six long-term survivors could be followed by coronary angiography. At 1 year, vasculopathy was assessed in nine patients (17%). Of the 18 patients investigated at 2 years thus far, an additional three patients were found to have vasculopathy. In the control group vasculopathy was comparable, being 13% after 1 year and 20% after 2 years. A significantly lower incidence of rejections and lower creatinine values were found in the study group within the entire observation period (p < 0.05)., Conclusions: We conclude that Angiopeptin treatment appears to be safe without significant side effects; it may reduce the number of acute rejections, at least during the first year after heart transplantation. However, the results of the 2-year follow-up in the remaining patients would have to be included in assessing the effect of Angiopeptin. Long-term follow-up will be necessary to decide whether Angiopeptin will be helpful in reducing the incidence of transplant vasculopathy.

The toxicity of long-term immunosuppressive therapy has become a major concern in long-term follow-up of heart transplant recipients. In this respect the quality of renal function is undoubtedly linked to cyclosporin A (CsA) drug levels. In cardiac transplantation, specific CsA trough levels have historically been maintained between 250 and 350 micrograms/L in many centers without direct evidence for the necessity of such high levels while using triple-drug immunosuppression. This retrospective analysis compares the incidence of acute and chronic graft rejection as well as overall mortality between groups of patients with high (250 to 350 micrograms/L) and low (150 to 250 micrograms/L) specific CsA trough levels. A total of 332 patients who underwent heart transplantation between October 1985 and October 1992 with a minimum follow-up of 30 days were included in this study (46 women and 276 men; aged, 44 +/- 12 years; mean follow-up, 1,122 +/- 777 days). Standard triple-drug immunosuppression included first-year specific CsA target trough levels of 250 to 300 micrograms/L. Patients were grouped according to their average creatinine level in the first postoperative year (group I, < 130 mumol/L, n = 234; group II, > or = 130 mumol/L, n = 98). The overall 5-year survival excluding the early 30-day mortality was 92% (group I, 216/232) and 91% (group II, 89/98) with 75% of the mortality due to chronic rejection. The rate of rejection for the entire follow-up period was similar in both groups (first year: group I, 3.2 +/- 2.6 rejection/patient/year; group II, 3.6 +/- 2.7 rejection/patient/year; p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

Palliative intubation of the esophagus for a malignant tracheoesophageal fistula is often complicated by difficulty in obtaining a tight seal. We have overcome the problem in three instances by placing a bifurcated, foam-cuffed stent in the trachea.

Ischemic airway complications after lung transplantation remain a significant problem despite the use of bronchial omentopexy. Clinical observations suggest that enhancement of vascular ingrowth could possibly increase the efficacy of a bronchial omental flap. This study was therefore designed to investigate whether basic fibroblast growth factor can enhance blood supply of an ischemic airway by acceleration of vascular ingrowth in a rabbit autotransplant model. Segments of the trachea were harvested and transplanted into a subcutaneous pouch. The animals were randomly assigned to one of four groups: group I, no omentopexy; group II, omentopexy; group III, omentopexy and fibrin glue; or group IV, omentopexy and fibrin glue enriched with 2.5 micrograms basic fibroblast growth factor. After 14 days the animals were sacrificed. The extent of perfusion was investigated by means of radioactive microspheres. The morphology of the tracheal segments was investigated in a blinded fashion macroscopically, by means of light microscopy, and by means of scanning electron microscopy. The radioactivity measurements revealed a significantly increased perfusion of group IV (77% +/- 42%) as compared with groups I (17% +/- 13%) and III (20% +/- 16%). By macroscopic and light microscopic assessment, the epithelial integrity of group IV was significantly improved compared with groups I and II. At electron microscopy the integrity of group IV was significantly superior to all remaining groups. We conclude that a deposit of basic fibroblast growth factor and fibrin glue appears to increase revascularization of an ischemic airway from omentum and thus results in improved epithelial preservation of a tracheal autograft.

Refixation of dissected aortic layers with gelatin-resorcin-formaldehyde/glutaraldehyde (GRFG) adhesive represents a new option in the surgical treatment of aortic dissection. Because of its ability to reinforce the delicate structures of the acutely dissected aortic wall, GRFG has been used increasingly in recent years. However, the biomechanical properties of the adhesive are still unclear, and little is known regarding the optimal mode of its application. In an ex vivo study, aortic specimens from sheep were glued with warm (45 degrees C) adhesive under wet and dry conditions and submitted to defined degrees of compression (5 Newtons [N], 20 N). Bonded specimens were retracted to assess tensile strength and elasticity compared with two reference adhesives: cyanoacrylate gel and fibrin glue. Gelatin-resorcin-formaldehyde/glutaraldehyde and cyanoacrylate gel showed similar results at 5 N. Both provided better adhesion when applied under dry conditions (GRFG 5 N: dry, 3.5 +/- 1.6 N/cm2; wet, 1.4 +/- 1.0 N/cm2; cyanoacrylate gel 5 N: dry, 4.8 +/- 1.8 N/cm2; wet, 3.2 +/- 1.3 N/cm2). At 20 N, GRFG tensile strength was significantly increased for either condition compared with values at 5 N (GRFG 20 N: dry, 17.1 +/- 4.2 N/cm2; wet, 4.8 +/- 1.8 N/cm2). Fibrin glue demonstrated only weak adhesive properties even under dry conditions (fibrin glue 5 N: dry, 0.8 +/- 0.3 N/cm2). Gelatin-resorcin-formaldehyde/glutaraldehyde has good adhesive properties both in wet and dry tissue. Bonding capacity can be substantially increased when applied on dry surfaces and at increased pressures.