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Biomedical subjects

R C Robbins

Publications and source records attributed to R C Robbins.

At least 55 records · Page 3Linked to original sources
PubMed1999

Cervical aortic arch with pseudocoarctation: presentation with spontaneous rupture.

A 23-year-old man presented with hypotension secondary to a left hemothorax. Diagnostic studies revealed a left cervical arch associated with a redundant tortuous pseudocoarctation in the proximal descending thoracic aorta. Operative exploration revealed an aortic rupture just proximal to the pseudocoarctation. Resection of the diseased aorta and tube graft replacement was performed under circulatory arrest. The patient was discharged home on the 12th postoperative day.

Adult↗
PubMed1999

Heart-lung transplantation for primary pulmonary hypertension.

BACKGROUND: The operation of choice for primary pulmonary hypertension remains controversial, as heart-lung transplantation, single-lung transplantation, and double-lung transplantation have all been advocated. METHODS: We reviewed our institution's experience with heart-lung transplantation for primary pulmonary hypertension. RESULTS: Thirty-nine patients had heart-lung transplantation for primary pulmonary hypertension. Operative mortality rate was 18%, and actuarial survival was 72% at 1 year, 67% at 2 years, and 42% at 5 years. Freedom from obliterative bronchiolitis was 91% at 1 year, 83% at 2 years, and 70% at 5 years. Freedom from obliterative bronchiolitis-related death was 100% at 1 year, 90% at 2 years, and 87% at 5 years. Freedom from accelerated graft coronary disease was 92% at 5 years. The most frequent causes of death were infection, obliterative bronchiolitis, and accelerated graft coronary disease. CONCLUSIONS: Heart-lung transplantation results in survival comparable to that reported for single or double lung transplantation. Obliterative bronchiolitis is a significant cause of late death but seems to occur less frequently with heart-lung transplantation than with lung transplantation alone. Accelerated coronary graft disease is rare in the first 5 years after transplantation.

Adolescent↗
PubMed1999

Pressure delivery of AS-ICAM-1 ODN with LFA-1 mAb reduces reperfusion injury in cardiac allografts.

BACKGROUND: The goal of this study is to determine the effects of ex vivo hyperbaric pressure administration of AS-ICAM-1 ODN and systemic anti-LFA-1 mAb treatment on reperfusion injury in the rat cardiac allograft model. METHODS: A PVG to ACI functional heterotopic rat heart model was used. Donor hearts were treated with either saline or AS-ICAM-1 ODN and 5 atm of hyperbaric pressure for 45 minutes. Anti-LFA-1 mAb was administered systemically prior to reperfusion of the allograft. Allografts were procured 24 hours after transplantation for assessment of reperfusion injury or 72 hours to determine ICAM-1 protein expression. RESULTS: Ex vivo administration of AS-ICAM-1 ODN led to decreases in percentage wet weight (77.1+/-0.83% vs 78.7+/-1.0%, p < 0.05), myeloperoxidase activity (3.14+/-0.72 vs 4.07+/-0.59, p < 0.05), contraction band necrosis (6.4+/-6.47% vs 21.1+/-7.43%, p < 0.01), and ICAM-1 protein expression determined by immunohistochemistry compared to saline controls. Treatment with anti-LFA-1 mAb resulted in decreases in wet weight ratio (76.7+/-0.63%, p < 0.05 vs saline), myeloperoxidase activity (3.58+/-0.39, p < 0.05 vs saline) and contraction band necrosis (11.8+/-3.56%, p < 0.05 vs saline). Combination of pressure administration of AS-ICAM-1 ODN and anti-LFA-1 mAb decreased wet weight ratios (77.1+/-0.93%, p < 0.05 vs saline), myeloperoxidase activity (2.88+/-0.44, p < 0.01 vs saline), and contraction band necrosis (6.75+/-5.67%, p < 0.05 vs saline). CONCLUSIONS: Ex vivo pressure mediated delivery of AS-ICAM-1 ODN decreases ICAM-1 protein expression, reduces reperfusion injury in rodent cardiac allografts, and is more effective than anti-LFA-1 mAb treatment alone.

Animals↗
PubMed1999

Bridge to transplant with the Novacor left ventricular assist system.

The Novacor left ventricular assist system is an implantable, electrically powered, wearable system that has been successfully used as a bridge to transplant since 1984. The pump is placed anterior to the left posterior rectus sheath with the percutaneous drive line positioned in the right lower abdominal wall. The seamless polyurethane blood sac is compressed by two solenoid-driven pusher plates. The inflow and outflow valves are porcine prostheses. The use of wearable external power packs facilitate patient mobility and rehabilitation before transplantation and may provide long-term support to selected patients as an alternative to transplantation.

Equipment Design↗
PubMed1999

Thirty years of cardiac transplantation at Stanford university.

BACKGROUND: The experience with 30 years of cardiac transplantation at Stanford University Medical Center was reviewed. A total of 954 transplants were performed in 885 patients. Patients were divided into 3 groups based on immunosuppression received: group I, no cyclosporine (INN: ciclosporin) (n = 201) (January 1968-November 1980); group II, cyclosporine (n = 248) (December 1980-June 1987); and group III, cyclosporine + OKT3 (n = 436) (July 1987-March 1998). RESULTS: The 1-, 5-, and 10-year actuarial survivals were 68%, 41%, and 24% (group I); 80%, 57%, and 37% (group II); and 85%, 68%, and 46% (group III) (I vs II, P <.01; I vs III, P <.005; and II vs III, P <.005). The 1-, 5-, and 10-year actuarial death rates from rejection were 8%, 12%, and 14% (group I); 5%, 7%, and 7% (group II); and 2%, 5%, and 5% (group III) (I vs II, P = not significant; I vs III, P <.005; and II vs III, P <.005). The 1-, 5-, and 10-year actuarial death rates from infection were 25%, 43%, and 50% (group I); 8%, 17%, and 29% (group II); and 6%, 11%, and 16% (group III) (I vs II, P <.005; I vs III, P <.005; and II vs III, P <.05). The 1-, 5-, and 10-year actuarial death rates from graft coronary artery disease were 0%, 5%, and 13% (group I); 0%, 12%, and 19% (group II); and 1%, 6%, and 9% (group III) (I vs II, P <.01; I vs III, P <.005; and II vs III, P = not significant). There have been 69 retransplants in 67 patients with 1-, 5-, and 10-year actuarial survivals of 49%, 27%, and 15%, respectively. CONCLUSIONS: The evolution of 3 decades of experience with cardiac transplantation has resulted in improved overall survival. The incidence of rejection and of death from infection and graft coronary artery disease have decreased over time, primarily as a result of improvements in immunosuppression and in the prevention and treatment of infection. Continued advances in perioperative management and the development of more specific, less toxic immunosuppressive agents could further refine this initial experience and improve the survival and quality of life of patients after cardiac transplantation.

Academic Medical Centers↗
PubMed1999

Sulfasalazine inhibits reperfusion injury and prolongs allograft survival in rat cardiac transplants.

INTRODUCTION: Reperfusion injury is an inflammatory cell-mediated response that causes tissue damage immediately following transplantation, and has been implicated in the development of acute and chronic rejection. NF-kappaB is a transcription factor that upregulates adhesion molecules ICAM-1, VCAM-1, and ELAM-1 following reperfusion. We hypothesized that treatment with sulfasalazine, a potent inhibitor of NF-kappaB, would decrease adhesion molecule expression, decrease reperfusion injury, and prolong allograft survival in rat cardiac transplants. METHODS: Heterotopic rat heart transplants were performed. Donor allografts were treated with saline, sulfasalazine (SSA), or lipopolysaccharide (LPS), a potent inducer of NF-kappaB activity. Reperfusion injury was assessed with cardiac edema (percent wet weight), neutrophil infiltration (MPO activity), and histologic damage (contraction band necrosis). Immunohistochemistry was performed to analyze protein expression. Acute rejection was determined by daily palpation. RESULTS: Treatment with a single 100 mg/kg intraperitoneal injection of sulfasalazine decreased reperfusion injury compared to saline controls (MPO activity, saline: 2.1+/-0.3, SSA: 1.2+/-0.31, P < 0.005; % wet weight, saline 77.6+/-1.1%; SSA 75.8+/-1.0%, P < 0.005; contraction band necrosis, saline: 13.1+/-2.5%, SSA: 6.1+/-3.4%, P < 0.001). LPS administration increased all parameters of reperfusion injury. Treatment with sulfasalazine prior to LPS also decreased reperfusion injury compared to LPS and saline groups. Sulfasalazine treatment decreased ICAM-1 and VCAM-1 protein expression. Administration of 500 mg/kg sulfasalazine increased graft survival to 15.4+/-1.8 days compared to saline (6.8+/-1.4 days, P < 0.005). CONCLUSION: Treatment with sulfasalazine is an effective method to decrease reperfusion injury and prolong allograft survival in a rat cardiac transplantation model.

Animals↗
PubMed1998

In vivo detection and imaging of phosphatidylserine expression during programmed cell death.

One of the earliest events in programmed cell death is the externalization of phosphatidylserine, a membrane phospholipid normally restricted to the inner leaflet of the lipid bilayer. Annexin V, an endogenous human protein with a high affinity for membrane bound phosphatidylserine, can be used in vitro to detect apoptosis before other well described morphologic or nuclear changes associated with programmed cell death. We tested the ability of exogenously administered radiolabeled annexin V to concentrate at sites of apoptotic cell death in vivo. After derivatization with hydrazinonicotinamide, annexin V was radiolabeled with technetium 99m. In vivo localization of technetium 99m hydrazinonicotinamide-annexin V was tested in three models: fuminant hepatic apoptosis induced by anti-Fas antibody injection in BALB/c mice; acute rejection in ACI rats with transplanted heterotopic PVG cardiac allografts; and cyclophosphamide treatment of transplanted 38C13 murine B cell lymphomas. External radionuclide imaging showed a two- to sixfold increase in the uptake of radiolabeled annexin V at sites of apoptosis in all three models. Immunohistochemical staining of cardiac allografts for exogenously administered annexin V revealed intense staining of numerous myocytes at the periphery of mononuclear infiltrates of which only a few demonstrated positive apoptotic nuclei by the terminal deoxynucleotidyltransferase-mediated UTP end labeling method. These results suggest that radiolabeled annexin V can be used in vivo as a noninvasive means to detect and serially image tissues and organs undergoing programmed cell death.

Animals↗
PubMed1998

Paradoxical embolism of a shotgun pellet.

Paradoxical embolism of a projectile from the venous to arterial system is a rare occurrence, which can cause diagnostic confusion. We present a case of venous embolism of a shotgun pellet from the left upper extremity to the noncoronary sinus of the aortic valve across a secundum-type atrial septal defect. Prevention of distal embolism of the pellet was presumably a result of its containment by flow vortices created within the sinuses of Valsalva.

Adult↗
PubMed1998

Congenital diaphragmatic hernia associated with aortic coarctation.

Congenital diaphragmatic hernia (CDH) may be associated with other anomalies, most frequently cardiovascular in nature. Despite fetal echocardiography, diagnosis of an accompanying cardiac malformation often is not made until after birth and sometimes not until after extracorporeal membrane oxygenation (ECMO) has been instituted. Aortic coarctation associated with CDH may occur as an isolated, surgically correctable malformation or it may be a component of the usually fatal left heart "hypoplasia" or "smallness" syndrome. The authors present two cases of aortic coarctation associated with CDH requiring ECMO that illustrate the management challenges of these coincident diagnosis. In one case, the accompanying coarctation was suspected and required precannulation angiography for confirmation, whereas in the other case, the diagnosis of coarctation was not made until after ECMO cannulation. Depending on its anatomic location and severity, an aortic coarctation associated with life-threatening CDH may limit the physiological efficacy of venoarterial ECMO. Furthermore, arterial cannulation for extracorporeal support requires that flow through the remaining carotid artery be maintained during aortic reconstruction, which may prove difficult for lesions best treated by subclavian flap angioplasty. When the diagnosis of coincident aortic coarctation and CDH is suspected or proven before institution of extracorporeal support, serious consideration should be given to venovenous bypass, because this may provide better postductal oxygenation and facilitate aortic repair with the option of left carotid artery inflow occlusion.

Aortic Coarctation↗
PubMed1998

The use of technetium Tc 99m annexin V for in vivo imaging of apoptosis during cardiac allograft rejection.

OBJECTIVE: Apoptosis, or programmed cell death, has been suggested as a mechanism of immunologic injury during cardiac allograft rejection. We tested the hypothesis that technetium Tc 99m annexin V, a novel radiopharmaceutical used to detect apoptosis, can be used to detect cardiac allograft rejection by nuclear imaging. METHODS: Untreated ACI rats served as recipients of allogeneic PVG rat (n = 66) or syngeneic ACI rat (n = 30) cardiac grafts. Untreated recipient animals underwent 99mTc-annexin V imaging daily for 7 days. Region of interest analysis was used to quantify the uptake of 99mTc-annexin V. Immediately after imaging grafts were procured for histopathologic analysis and terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate-biotin nick-end labeling of apoptotic nuclei. One group was treated with 10 mg/kg/d cyclosporine (INN: ciclosporin) commencing on day 4 after transplantation (n = 6). RESULTS: Untreated allografts showed histologic signs of rejection 4 days after transplantation. Apoptotic nuclei could be demonstrated in myocytes, endothelial cells, and graft-infiltrating cells of all rejecting allografts. Nuclear imaging revealed a significantly greater uptake of 99mTc-annexin V in rejecting allogeneic grafts than in syngeneic grafts on day 4 (P = .05), day 5 (P < .001), day 6 (P < .001), and day 7 (P = .013) after transplantation. A correlation between the histologic grade of acute rejection and uptake of 99mTc-annexin V was observed (r2 = 0.87). After treatment of rejection with cyclosporine, no apoptotic nuclei could be identified in allografts and uptake of 99mTc-annexin V decreased to baseline. CONCLUSIONS: Apoptosis occurs during acute cardiac allograft rejection and disappears after treatment of rejection. 99mTc-annexin V can be used to detect and monitor cardiac allograft rejection.

Animals↗
PubMed1998

Ex vivo gene therapy prevents chronic graft vascular disease in cardiac allografts.

OBJECTIVE: We hypothesized that ex vivo hyperbaric transfection of antisense oligodeoxynucleotides for blockade of intercellular adhesion molecule-1, an important mediator of cell adhesion and T-cell co-stimulation, would reduce chronic graft vascular disease in cardiac allografts. METHODS: PVG hearts underwent ex vivo transfection with antisense, reverse antisense intercellular adhesion molecule-1 oligodeoxynucleotide (80 micromol/L), or saline solution at 3 atm pressure for 45 minutes at 4 degrees C and were transplanted heterotopically into ACI recipients with or without treatment with intercellular adhesion molecule-1 (1A29) or leukocyte function associated antigen-1 (WT.1) monoclonal antibodies. Transfection efficiency was confirmed with fluorescein isothiocyanate-labeled oligodeoxynucleotides and fluorescent microscopy. Efficacy of intracellular adhesion molecule-1 blockade was assessed with the use of immunohistochemistry. Graft reperfusion injury was evaluated at 6 to 24 hours by neutrophil infiltration (myeloperoxidase [MPO]), cardiac edema (%wt/wt), and histologic injury (percent contraction band necrosis). Grafts from recipients treated with cyclosporine A (5 mg/kg per day, days 0 to 9) were scored for chronic graft vascular disease on postoperative day 90 ranging from 0 (no involvement) to 4 (>50% vascular occlusion). RESULTS: Transfection was highly efficient (fluorescein isothiocyanate-labeled oligodeoxynucleotides in 48%+/-5% of total myocardial nuclei) and effective at blocking intracellular adhesion molecule-1 expression (positive area in allografts taken on postoperative day 3 was reduced from 100%+/-0% to 52%+/-14%, n=4). Blockade with antisense oligodeoxynucleotides versus monoclonal antibodies was less effective at preventing reperfusion injury while more effective at reducing chronic graft vascular disease (score 0.98+/-0.48, p < 0.05). Reverse antisense oligodeoxynucleotides and vector control (antisense oligodeoxynucleotide infusion without pressure) groups failed to demonstrate this beneficial effect. CONCLUSION: Hyperbaric transfection of antisense oligodeoxynucleotides proved highly efficient, effective at blockade of intracellular adhesion molecule-1, and demonstrated a sequence-specific reduction in chronic graft vascular disease. This highly targeted alteration of donor organ immunogenicity may have an important future role in clinical immunosuppressive strategies.

Animals↗
PubMed1998

Superior vena cava syndrome after heart transplantation: percutaneous treatment of a complication of bicaval anastomoses.

OBJECTIVES: Our objectives were (1) to investigate the incidence and cause of symptomatic superior vena caval anastomotic stenosis and central venous thrombosis in patients receiving heart or heart-lung transplantation and (2) to explore percutaneous methods of thrombolysis and endoluminal intervention to treat these complications. METHODS: Review of 1016 cases revealed three cases of superior vena cava syndrome. Anatomy, surgical technique, and medical risk factors were examined. Percutaneous treatments, including urokinase thrombolysis, mechanical thrombolysis, balloon angioplasty, and stent placement, were attempted. RESULTS: All three of these patients underwent transplantation by means of the bicaval anastomotic technique. In addition, the diameters of the donor and recipient cavae were grossly mismatched in all three. Stenoses in all three patients were successfully treated percutaneously with balloon angioplasty and stent placement. Treatment of the accompanying large-volume thrombosis was problematic in these patients, and two had hemorrhagic complications of urokinase thrombolysis. A mechanical thrombolysis device was used successfully in the third patient. CONCLUSIONS: Anastomotic stricture and central venous thrombosis is an uncommon complication of the bicaval anastomotic technique of heart and heart-lung transplantation. Discrepancy between donor and recipient caval diameters appears to be the major risk factor. Endoluminal thrombolysis and stenting provides rapid and enduring relief of symptoms and precludes repeat sternotomy, cardiopulmonary bypass, and general anesthesia.

Adult↗
PubMed1998

Arrhythmias and thromboembolic complications after the extracardiac Fontan operation.

BACKGROUND: Late morbidity and mortality after the Fontan operation are largely due to atrial arrhythmias, ventricular failure, and thrombus formation. The extracardiac Fontan procedure avoids extensive atrial manipulation and suture lines, theoretically minimizing the impetus for these events. We examined our experience with the extracardiac Fontan operation with particular attention to thromboembolism and arrhythmias. METHODS AND RESULTS: We retrospectively reviewed the medical and surgical records of all 16 patients who underwent an extracardiac Fontan operation between July 1993 and May 1996. Fifteen patients (94%) were in sinus rhythm before the operation. In the immediate postoperative period, seven (44%) had arrhythmias consisting of accelerated junctional rhythm and ectopic atrial rhythm. No associated hemodynamic compromise and no early deaths occurred. Patients were followed up for 3 to 34 months after the Fontan operation. Arrhythmias were detected in eight patients (50%) on surface electrocardiograms, and seven (44%) showed evidence of sinus node dysfunction on 24-hour Holter monitor studies. Thrombi were found in three patients (19%). All patients were asymptomatic, with no evidence of conduit obstruction by echocardiogram. CONCLUSIONS: The incidence of hemodynamically significant tachyarrhythmias appears to be reduced after the extracardiac Fontan operation. A significant percentage of patients have evidence of sinus node dysfunction, suggesting the presence of other surgical or nonsurgical factors responsible for this finding. Our incidence of thrombotic events is similar to previous reports with other Fontan modifications. It appears to be a reasonable option to maintain these patients on anticoagulation indefinitely.

Arrhythmias, Cardiac↗