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The results of a combined analysis and separate analyses of four multicenter, randomized, parallel group studies that evaluated the effects of once-daily topical administration of becaplermin gel for the treatment of chronic, full thickness, lower extremity diabetic ulcers are presented. The four studies included a total of 922 patients with nonhealing lower extremity diabetic ulcers of at least 8 weeks' duration. Following initial complete sharp debridement of the ulcer, patients were randomized to receive a standardized regimen of good ulcer care alone, good ulcer care plus placebo gel, or good ulcer care plus becaplermin gel-30 microgram/g, or good ulcer care plus becaplermin gel-100 microgram/g, with various combinations of regimens used in the four studies. Safety was assessed by monitoring adverse events and by clinical laboratory evaluations. Meta-analytic statistical techniques were used in the combined analysis to establish homogeneity of treatment comparisons across studies. Based on an analysis of patients with baseline ulcer area common to all trials (

Necrotizing enterocolitis (NEC) is the leading cause of death from gastrointestinal disease in premature infants and is steadily rising in frequency. Patients who develop NEC have a very high mortality, illustrating the importance of developing novel prevention or treatment approaches. We and others have shown that NEC arises in part from exaggerated signaling via the bacterial receptor, Toll-like receptor 4 (TLR4) on the intestinal epithelium, leading to widespread intestinal inflammation and intestinal ischemia. Strategies that limit the extent of TLR4 signaling, including the administration of amniotic fluid, can reduce NEC development in mouse and piglet models. We now seek to test the hypothesis that a secretome derived from amnion-derived cells can prevent or treat NEC in preclinical models of this disease via a process involving TLR4 inhibition. In support of this hypothesis, we show that the administration of this secretome, named ST266, to mice or piglets can prevent and treat experimental NEC. The protective effects of ST266 occurred in the presence of marked TLR4 inhibition in the intestinal epithelium of cultured epithelial cells, intestinal organoids, and human intestinal samples ex vivo, independent of epidermal growth factor. Strikingly, RNA-seq analysis of the intestinal epithelium in mice reveals that the ST266 upregulates critical genes associated with gut remodeling, intestinal immunity, gut differentiation. and energy metabolism. These findings show that the amnion-derived secretome ST266 can prevent and treat NEC, suggesting the possibility of novel therapeutic approaches for patients with this devastating disease. NEW & NOTEWORTHY This work provides hope for children who develop NEC, a devastating disease of premature infants that is often fatal, by revealing that the secreted product of amniotic progenitor cells (called ST266) can prevent or treat NEC in mice, piglet, and "NEC-in-a-dish" models of this disease. Mechanistically, ST266 prevented bacterial signaling, and a detailed transcriptomic analysis revealed effects on gut differentiation, immunity, and metabolism. Thus, an amniotic secretome may offer novel approaches for NEC.

Objective: An exploratory phase II, multicenter, open-label, clinical trial (NCT03687632) was conducted to evaluate the safety and effectiveness in treating persistent corneal epithelial defects (PEDs) with ST266, a proprietary novel multi-cytokine platform biologic solution secreted by cultured Amnion-derived Multipotent Progenitor (AMP) cells., Methods: Subjects with a PED were treated with ST266 eye drops 4 times daily for 28 days, then followed for 1 week. Safety was assessed by monitoring of adverse events (AEs) and serious adverse events (SAEs). Efficacy was assessed by measuring the area of the PED by slit lamp biomicroscopy. Tolerability of ST266, percentage of eyes with complete healing, reduction in area of the epithelial defect, and maintenance of a reduction in the area of the epithelial defect 7 days after treatment were recorded., Results: Thirteen patients were enrolled into the trial at one of eight sites. The first patient withdrew after 5 days. The remaining 12 patients with PEDs with median duration of 39 days (range = 12 to 393 days) completed treatment. Ten of the 12 eyes had been refractory to treatment with various conventional therapies prior to enrollment. After 28 days of treatment, there was a significant decrease in mean PED area compared with baseline (66.4% ± 35.3%, P = 0.001). At follow-up, 1 week after completion of treatment, on day 35, the PED area was further reduced by 78.8% ± 37.5% (P = 0.01) compared with baseline. During 28 days of treatment, 5 eyes (41.7%) had complete wound closure. There were no AEs of concern thought to be related to the drug, and no SAEs were noted., Conclusions: In this trial, we found ST266 eye drops might promote corneal epithelization, thereby reducing the PED area, including in refractory cases in a wide range of etiologies. ST266 was well-tolerated by most patients.

Objective: To establish a safety profile for amnion-derived cellular cytokine solution following topical application in patients undergoing whole breast radiotherapy for breast cancer., Materials and Methods: Twenty female patients with early-stage breast cancer were enrolled in 2 separate cohorts of an institutional review board-approved phase I protocol. Cohort 1 consisted of 10 patients who received topical amnion-derived cellular cytokine solution to the breast immediately following the first 10 fractions of whole breast radiotherapy. Cohort 2 consisted of 10 additional patients who fit the same criteria as the initial cohort but received topical amnion-derived cellular cytokine solution following the development of at least grade I breast erythema. Blood samples were tested for the presence of proteins in amnion-derived cellular cytokine solution as well as routine hematologic functions., Results: Amnion-derived cellular cytokine solution did not induce overproduction of any cytokines sampled, and there was no evidence of "cytokine storm." It also showed no significant absorption systemically following topical delivery. No patients developed an adverse event. There were no patterns of changes in vital signs or clinical laboratory tests that were related to the treatment regimen., Conclusion: In this safety trial, the topical application of amnion-derived cellular cytokine solution in both intact and denuded, irradiated skin was found to be safe, and showed no evidence of systemic absorption. No cosmetic changes were identified long term. Patient blood chemistry was not adversely affected, indicating the absence of an anaphylactic response and no evidence "cytokine storm" was identified. Amnion-derived cellular cytokine solution is safe to use topically in clinical protocols.

Objective: Growth factors demonstrate mixed results improving wound healing. Amnion-derived multipotent cells release physiologic levels of growth factors and tissue inhibitors of metalloproteinases. This solution was tested in models of acute and chronic wound healing., Methods: Acute model: Sprague-Dawley rats underwent laparotomy incisions. The midline fascia was primed with phosphate-buffered saline, unconditioned media, or amnion-derived cellular cytokine suspension prior to incision. Breaking strength of laparotomy wounds was tested with an Instron tensiometer. Incisional hernia formation was measured after 28 days. Chronic model: Chronic, infected granulating wounds were produced in rats by excising full thickness burn eschars inoculated with Escherica coli. Granulating wounds were treated with unconditioned media or amnion-derived cellular cytokine suspension. Treatments were applied either on day 0 and day 7 or day 0 and then every other day. Wounds were traced every 72 hours and biopsied for quantitative bacteriology., Results: Acute model: Priming with amnion-derived cellular cytokine suspension increased the breaking strength of laparotomy incisions in comparison with phosphate-buffered saline or unconditioned media (P < .05). Acute wound failure and incisional hernia formation was 100% in the phosphate-buffered saline and unconditioned media groups and 18% in the amnion-derived cellular cytokine suspension-treated group (P <.05). Chronic model: The rate of wound closure was accelerated in amnion-derived cellular cytokine suspension-treated chronic wounds (P < .05). Multidosing improved the effect., Conclusions: A physiologic solution of cytokines and tissue inhibitors of metalloproteinases improves healing in models of acute and chronic wounds. Such a cocktail can be produced from amnion-derived multipotent progenitor cells.

Objective: Wound repair is a complex integration of dynamic processes mediated by humeral messages controlling the levels of cytokines, growth factors, and matrix metalloproteinases in the wound space. Isolated growth factors and growth factor combinations have been used to accelerate wound healing with limited success. A cellular cytokine solution can be collected by harvesting the proteins released from amnion-derived multipotent progenitor cells. The purpose of this study was to compare levels of cytokines/growth factors in amnion-derived cellular cytokine solution with physiological levels reported in the medical literature., Methods: Amnion-derived multipotent progenitor cells were grown to confluency, and the proteins secreted were characterized by qualitative and quantitative analysis. These results were compared with physiologic levels reported in the medical literature., Results: The results demonstrated that amnion-derived cellular cytokine solution contained physiologic levels of cytokines relevant to wound healing, including platelet-derived growth factor, vascular endothelial growth factor, angiogenin, transforming growth factor beta 2, tissue inhibitor of metalloproteinase-1, and tissue inhibitor of metalloproteinase-2. The ranges (mean +/- standard deviation) were as follows: platelet-derived growth factor, 86 +/- 33 pg/mL; vascular endothelial growth factor, 5.7 +/- 1.5 ng/mL; angiogenin, 1.0 +/- 0.33 ng/mL; transforming growth factor beta 2, 500 +/- 330pg/mL; tissue inhibitor of metalloproteinase-1, 530 +/- 140 ng/mL; and tissue inhibitor of metalloproteinase-2230 +/- 40 ng/mL. These levels are comparable with the physiologic levels reported in the literature., Conclusions: The physiologic levels of cytokines important to healing found in amnion-derived cellular cytokine solution suggest that amnion-derived cellular cytokine solution may be of benefit in healing certain acute and chronic wounds.

Background: Diabetic foot ulcer is a major health care problem that leads to amputation., Methods: Patients with full-thickness diabetic neurotrophic foot ulcers present for longer than 8 weeks without healing were entered into one of five randomized, prospective, blinded clinical trials comparing treatment with platelet-derived growth factor (PDGF) or placebo gel for up to 20 weeks. The purpose of these trials was to assess the safety and efficacy of PDGF used with good wound care. Each patient had an adequate arterial blood supply, was free of infection, was off-loaded, and was extensively débrided. The ulcers had been present for at least 8 weeks., Results: A total of 922 patients were entered into the study. Analysis of ulcers with a baseline area of less than 10 cm (95 percent of patients) showed that patients treated with PDGF at 100 mug/g had a significant increase in complete healing compared with patients given placebo (50 percent versus 36 percent, p < 0.007). PDGF also decreased the time to complete healing by 30 percent (14 weeks versus 20 weeks, p = 0.01). Adverse events were similar in both treatment groups, as were recurrent ulcer rates., Conclusion: PDGF applied once daily was effective in healing chronic diabetic neurotrophic foot ulcers when used in conjunction with good wound care.

Outcome measures of venous ulcer healing are not uniformly accepted. Stringent criteria of 100% closure fail to provide information of healing over the entire span of repair. Wound-healing trajectories (plot of percentage of wound closure versus time of wound treatment) were constructed for 232 patients treated in eight clinical trials at two independent wound care/research centres. Trajectories were constructed for ulcers that totally healed (100% closure) and those that did not (<100% closure) over a 20-week period. Kaplan-Meier survival plots determined the percentage of patients achieving total healing versus time of treatment. The wound-healing trajectories were almost identical for patients achieving complete ulcer healing, as were the trajectories for patients with less than 100% closure. The trajectories for the ulcers healing completely were significantly different from those with <100% closure. Only 60% of all patients achieved 100% closure by 20 weeks. Using linear regression, it was predicted that it would take 31 weeks for all patients to achieve total healing. Total healing is an inadequate outcome measure for healing of venous stasis ulcers. Clinical trials using this measure would require excessive time periods. As wound-healing trajectories for patients treated at two centres mimic one another, shifting the wound-healing trajectory from one of impaired healing to one of a more ideal healing course may be considered a better outcome measure for determining healing of venous stasis ulcers.

Debridement is defined as the removal of nonviable material, foreign bodies, and poorly healing tissue from a wound. Although surgeons recognize the importance of debridement, few data have been generated in randomized trials to support its use. Debridement provides for removal of tissue with the highest bacterial count, reliable cultures, and identification of osteomyelitis. The most direct form of debridement is surgical excision. For patients who are poor candidates for surgical debridement or have limited access to a surgeon, other forms of debridement (including mechanical, autolytic, enzymatic, and biologic) can be used. Although operative debridement is best performed by those with surgical training, the other forms of debridement can be accomplished by other allied health care professionals. Debridement remains an important adjunct to good wound care, but questions of what type, how much, and how often it should be performed remain unresolved.

Healing of a wound is a dynamic process involving soluble mediators, a variety of cells, and extracellular matrix. These components are involved in a number of different processes or steps in healing, including coagulation, inflammation, fibroplasia, collagen deposition, epithelialization, and scar contraction with remodeling. The processes can be organized into three phases: inflammation, fibroplasia, and remodeling. The events in healing occur in an orderly and timely fashion, and there is significant overlap between each of the processes.

About 600,000 people in the United States are estimated to be affected by venous ulcers. The cornerstone of care of chronic venous ulcers involves the application of compression bandages. Other therapies include treatment of associated infection, treatment for edema and inflammation, and debridement when necessary. Repifermin, a recombinant human KGF-2 (fibroblast growth factor-10), exerts a proliferative effect on epithelial cells, in vitro and in vivo, and has been shown to accelerate wound healing in several experimental animal models. A randomized, double-blind, parallel-group, placebo-controlled, multicenter study was conducted to evaluate the safety and efficacy of topical repifermin treatment, for 12 weeks, in the healing of chronic venous ulcers in 94 patients. Repifermin was shown to accelerate wound healing, with significantly more patients achieving 75% wound closure with repifermin than with placebo. The treatment effect appeared more marked for a subgroup of patients with initial wound areas < or = 15 cm2 and wound ages of < or = 18 months. A longer duration of treatment (e.g., 26 weeks) may allow better differentiation of the benefit of repifermin compared with placebo, particularly with respect to complete wound closure. The safety assessment showed that repifermin was well tolerated.

Introduction: Postoperative care after infrarenal abdominal aortic aneurysm (AAA) repair has traditionally involved admission to the intensive care unit (ICU). With the advent of endovascular AAA repair, the management of open procedures has received increased scrutiny. We recently modified our AAA clinical pathway to include selective use of the ICU., Methods: Consecutive elective infrarenal AAA repairs performed by members of the vascular surgery division at a university medical center from 1994 to 1999 were analyzed retrospectively with a computerized database, the Medical Archival Retrieval System. Group I consisted of 245 patients who were treated in the ICU for 1 or more days, and Group II included 69 patients admitted directly to the floor. Ruptured, symptomatic, suprarenal, endovascular, and reoperative repairs were excluded. Outcome variables were compared over the 6-year period., Results: Floor admissions increased over the study period with 0%, 0%, 3.3%, 16.3%, 48.6%, and 43.6% of patients admitted directly to the surgery ward from 1994 to 1999. The average ICU length of stay declined from 4.6 to 1.2 days, whereas the hospital length of stay decreased from 12.5 to 6.8 days from 1994 to 1999. The change in ICU use had no effect on death (2.4% in Group I vs 0% in Group II). Major and minor morbidity was comparable. Hospital charges were significantly lower for patients in Group II., Conclusion: A policy of selective utilization of the ICU after elective infrarenal AAA repair is safe. It can reduce resource use without a negative impact on the quality of care.

Background: One goal of wound healing research is to discover agents to accelerate healing. Regulatory agencies have suggested stringent criteria to determine efficacy, that of 100% wound closure. Data analysis at a single point such as 100% closure does not provide detailed information about agent effectiveness over the entire span of healing., Hypothesis: Wound healing trajectories can provide such information and can be used to demonstrate utility as alternative end points for wound healing trials., Design: Data from 160 patients in 11 clinical trials of diabetic foot ulcers conducted at 2 centers were evaluated. Wound healing trajectories were constructed for patients whose wounds healed (100% closure) and those whose did not (<100% closure) over a 20-week period. The percentage of patients achieving total healing vs time of treatment was plotted and divided into patients receiving a test agent or placebo., Results: The healing trajectories were almost identical for patients achieving complete healing at the 2 centers, as were the trajectories for patients with less than 100% closure. However, the trajectories of patients achieving total healing were significantly different from those not achieving 100% closure. Fifty-two percent of all patients achieved 100% healing by 20 weeks; 61% of patients receiving an experimental agent had total healing compared with 39% of placebo-treated patients. Linear regression suggested that all patients would achieve total healing by 37 weeks., Conclusions: Since wound healing trajectories for diabetic foot ulcers treated at 2 centers so closely mimic one another, trajectories might be useful efficacy end points, and used to compare significant points along a continuum rather than a single static end point. Shifting of the wound healing trajectory from an impaired to a more ideal course may be considered when determining efficacy of new wound treatments.

Objective: The compression of femoral artery pseudoaneurysms is a time consuming, painful, and sometimes unsuccessful procedure. Thrombin injection has been advocated as a superior alternative. In this study, we compare our experiences with both techniques., Methods: All the records of femoral artery false aneurysms that were treated in the vascular laboratory from January 1996 to April 1999 were retrospectively reviewed. Treatment with ultrasound scan-guided compression was compared with treatment with dilute thrombin injection (100 U/mL)., Results: Both groups had similar demographics and aneurysm sizes (P >.2). Of the pseudoaneursyms, 88% were caused by cardiac catheterization and the others were the results of femoral artery access for cardiac surgery (6%), arteriography (5%), and renal dialysis (1%). Compression was successful in 25 of 40 patients (63%). Nine persistent aneurysms necessitated operation, and six were treated successfully with thrombin injection. Primary thrombin injection successfully obliterated 21 pseudoaneurysms in 23 patients. Overall, 27 of 29 pseudoaneurysms were treated successfully with thrombin injection (93%). Thrombosis occurred within seconds of the thrombin injection and required, on average, 300 units of thrombin (100 to 600 units). The patients who underwent successful compression required an average of 37 minutes of compression (range, 5 to 70 minutes) and required analgesia on several occasions. No patients in the thrombin group required analgesia or sedation. Neither group had complications. A cost analysis shows that thrombin treatment results in considerable savings in vascular laboratory resource use but not in overall hospital expenditures., Conclusion: Ultrasound scan-guided thrombin injection is a safe, fast, and painless procedure that completely obliterates femoral artery pseudoaneurysms. The shift from compressive therapy to thrombin injection reduces vascular laboratory use and is less expensive, although it does not significantly impact hospital costs.

Background: Severe oxygen-dependent chronic obstructive pulmonary disease (COPD) is considered by many to be a contraindication to open abdominal aortic aneurysm (AAA) repair. We reviewed our own experience with this patient population., Methods: From July 1995 to March 1999, 14 consecutive patients limited by home oxygen-dependent COPD underwent elective open infrarenal AAA repair. Their medical records were reviewed., Results: The mean aortic aneurysm size was 6.3 cm. The mean PaO2 = 70 mm Hg, PaCO2 = 45 mm Hg, forced expiratory volume in 1 second (FEV1) = 34% of predicted, and forced vital capacity (FVC) = 67% of predicted. All 14 patients were extubated within 24 hours, mean length of hospital stay was 5.9 days, and there were no perioperative deaths., Conclusions: Severe home oxygen-dependent COPD is not a contraindication to safe elective open AAA repair.

Purpose: The purpose of this study was to delineate the natural history of the progression of asymptomatic carotid stenosis., Methods: In a 10-year period, 1701 carotid arteries in 1004 patients who were asymptomatic were studied with serial duplex scans (mean follow-up period, 28 months; mean number of scans, 2.9/patient). At each visit, stenoses of the internal carotid artery (ICA) and the external carotid artery (ECA) were categorized as none (0 to 14%), mild (15% to 49%), moderate (50% to 79%), severe (80% to 99%), preocclusive, or occluded. Progression was defined as an increase in ICA stenosis to >/=50% for carotid arteries with a baseline of <50% or as an increase to a higher category of stenosis if the baseline stenosis was >/=50%. The Cox proportional hazards model was used for data analysis., Results: The risk of progression of ICA stenosis increased steadily with time (annualized risk of progression, 9.3%). With multivariate modeling, the four most important variables that affected the progression (P <.02) were baseline ipsilateral ICA stenosis >/=50% (relative risk [RR], 3.34), baseline ipsilateral ECA stenosis >/=50% (RR, 1.51), baseline contralateral ICA stenosis >/=50% (RR, 1.41), and systolic pressure more than 160 mm Hg (RR, 1. 37). Ipsilateral neurologic ischemic events (stroke/transient ischemic attack) occurred in association with 14.0% of the carotid arteries that were studied. The progression of ICA stenosis correlated with these events (P <.001), but baseline ICA stenosis was not a significant predictor., Conclusion: In contrast to recently published studies, we found that the risk of progression of carotid stenosis is substantial and increases steadily with time. Baseline ICA stenosis was the most important predictor of the progression, but baseline ECA stenosis also was identified as an important independent predictor. Contralateral ICA stenosis and systolic hypertension were additional significant predictors. We found further that the progression of ICA stenosis correlated with ischemic neurologic events but not baseline stenosis. The data provide justification for the use of serial duplex scans to follow carotid stenosis and suggest that different follow-up intervals may be appropriate for different patient subgroups.

Diabetic foot ulcers are a significant healthcare problem affecting more than 1 million patients at some point in their lifetime. Good ulcer care begins with thorough assessment of the ulcer, which includes determining whether the ulcer is infected and whether neuropathy or peripheral vascular disease is present. The principles of good wound care include use of proper footwear, non-weight-bearing limb support, use of appropriate antibiotics, debridement, aggressive revascularization, control of serum glucose levels, and careful monitoring of the ulcer. For refractory ulcers, new therapies, such as the use of exogenous recombinant growth factors, are being developed that may have a significant benefit in treating these ulcers and lowering the amputation rate.

Growth factors exert a powerful influence over wound healing. They control the growth, differentiation, and metabolism of cells. Although their influence on wound repair has been studied, there are only a few reports in which growth factors applied topically exerted a positive influence on wound repair. However, there is no doubt that they do control the wound environment. It is likely that their actions will be defined further, and the wound environment will be able to be controlled to achieve complete and durable wound healing in patients.

Most evidence indicates that nitric oxide plays a role in normal wound repair; however, involvement of inducible nitric oxide synthase (iNOS) has not been established. Experiments were carried out to determine the requirement for iNOS in closing excisional wounds. Wound closure was delayed by 31% in iNOS knockout mice compared with wild-type animals. An identical delay in wound closure was observed in wild-type mice given a continuous infusion of the partially selective iNOS inhibitor N6-(iminoethyl)-L-lysine. Delayed wound healing in iNOS-deficient mice was completely reversed by a single application of an adenoviral vector containing human iNOS cDNA (AdiNOS) at the time of wounding. Reverse transcription PCR identified iNOS mRNA expression in wild-type mice peaking 4-6 d after wounding, and confirmed expression of human iNOS in the adenoviral vector containing human iNOS cDNA-treated animals. These results establish the key role of iNOS in wound closure, and suggest a gene therapy strategy to improve wound healing in iNOS-deficient states such as diabetes, and during steroid treatment.

Growth factors applied topically to wounds can accelerate healing by stimulating granulation tissue formation and enhancing epithelialization. This has been suggested by several different studies of topically applied growth factors. It is clear, however, that topical growth factor therapy should not be considered as a substitute for good wound care, including surgical debridement or revascularization.

Purpose: A pathologic feature commonly associated with abdominal aortic aneurysms is the presence of variably sized and shaped intraluminal thrombus, which may be fundamental to the disease process. However, the precise role of the intraluminal thrombus in the formation, enlargement, and rupture of abdominal aortic aneurysms is unknown. The hypothesis tested in this study was whether there were structural features of aortic thrombi to suggest that it may be involved in the pathogenesis of abdominal aortic aneurysms. We have investigated this hypothesis using a variety of structural and biochemical techniques., Methods: Tests performed were light, transmission, and scanning electron microscopy; fluid permeability measurements; and Western blots., Results: Intraluminal thrombus found in abdominal aortic aneurysms is structurally complex and is traversed from the luminal to abluminal surface by a continuous network of interconnected canaliculi. Quantitative microscopic analysis of the thrombus shows cellular penetration for at least 1 cm from the luminal surface of the thrombus. Macro-molecular penetration may be unrestricted throughout the entire thickness of the thrombus. Fibrin deposition occurred throughout the thrombus, whereas fibrin degradation occurred principally at the abluminal surface., Conclusions: These principally structural studies support the hypothesis that the thrombus is a self-sustaining entity that may have significance in the pathophysiologic mechanism of abdominal aortic aneurysms.

Purpose: This study aims to describe the spectrum of clinical thrombotic events and to compare the methods of laboratory evaluation for the newly described prothrombotic factor V Leiden mutation., Methods: Specimens from 1376 patients with thrombotic events or their relatives were tested for the factor V Leiden mutation by polymerase chain reaction plus restriction digest from Jan. 1, 1995, to Mar. 31, 1996. Activated protein C (APC) resistance test data was available for 554 of these patients. Clinical information was available for 166 patients with the mutation., Results: Of 1376 patients tested for factor V Leiden mutation, 270 (19.6%) were positive, with 12 homozygotes and 258 heterozygotes. Of 554 patients for whom APC resistance data was available, 221 (39.9%) had low APC resistance ratios (< or = 2.4); of these only 97 (43.9%) were factor V Leiden-positive. Among 333 samples with normal or elevated APC resistance ratios, 19 (5.7%) were later identified with the factor V Leiden mutation, despite the normal screening test. One hundred fourteen of 166 patients (68.7%) with the mutation had at least one thrombotic event, most commonly deep venous thrombosis and pulmonary embolus. Arterial cerebrovascular thrombotic events occurred in 11 patients (10%), and myocardial infarctions in eight (7%). The mean age of all patients with arterial thrombotic events was 45.4 years., Conclusions: The factor V mutation is a common cause of venous thromboses but may also be associated with the early presentation of arterial thrombotic events. The APC resistance test is a sensitive screening assay but has limitations of its specificity in clinical practice.

Purpose: We reviewed our experience with a clinical pathway instituted in December 1993 for all nonurgent abdominal aortic aneurysm (AAA) surgery., Methods: We analyzed a reference group of 49 consecutive pre-pathway AAA patients (group I) and the 44 patients enrolled in the first year of the pathway (group II). On the basis of the interim review of data collected during the first year, pathway modifications were made, and 34 patients enrolled after these modifications (group III) were also analyzed., Results: Comparison of groups I and II showed that institution of the pathway resulted in a marginally significant reduction in mean charges of 14.7% (p = 0.09), and a slight fall in mean length of stay (LOS) (13.8 vs 13.1 days, NS) and mortality rate (4.1% vs 2.3%, NS). For group II, a significant correlate (p < 0.05) of increased charges was fluid overload as diagnosed by chest radiograph. This recognition led to active efforts to reduce perioperative fluid administration. Comparison of groups II and III revealed that the practice modifications led to marked reduction in the incidence of fluid overload (73% vs 24%; p < 0.01), mean charges (30.4% reduction; p < 0.05), mean LOS (13.1 vs 10.2 days; p < 0.05), and median LOS (11 vs 8 days). Multiple regression analysis of all pathway patients showed that preoperative renal insufficiency is a significant predictor of both increased LOS (p < 0.01) and charges (p < 0.01), but that age, sex, and coronary disease were not predictive. Of the postoperative parameters analyzed, important correlates of increased charges were acute renal failure (p < 0.01) and fluid overload (p < 0.01)., Conclusions: Institution of a clinical pathway for AAA repair resulted in significant charge reduction and a slight reduction in stay. Practice modifications based on interim data analysis yielded further significant reductions in charges and LOS, with overall per-patient charge savings (group I vs III) of 40.6% (p < 0.05) and overall LOS reduction of 3.5 days (p < 0.05). The reduction in actual charges was seen despite an overall increase in the hospital rate structure. Comparing groups I, II, and III, we found no indication of increasing mortality rate. Ongoing analysis has identified correlates of increased charges, potentially permitting identification of high-cost subgroups and more focused cost-control efforts. Rather than restricting management, clinical pathways with periodic data analysis may improve quality of care.

Background: There has been a broad interest in the use of growth factors to treat patients with chronic nonischemic diabetic ulcers., Study Design: One hundred eighteen patients were studied in a randomized, prospective, double-blind, multicenter trial comparing treatment with topically applied recombinant human platelet-derived growth factor (rhPDGF) or placebo (vehicle) and were treated until completely healed or to 20 weeks. All patients had aggressive sharp debridement of their ulcers before randomization and repeat debridement of callus and necrotic tissue as needed. The influence of debridement was evaluated by reviewing the records of the office visits where debridement was performed., Results: Forty-eight percent of patients treated with rhPDGF healed compared with 25 percent of patients who received placebo (p = 0.01). The mean percentage of office visits where debridement was performed was comparable for the two treatment groups: 46.8 percent (rhPDGF) and 48.0 percent (placebo). In general, a lower rate of healing was observed in those centers that performed less frequent debridement. The improved response rate observed with more frequent debridement was independent of the treatment group. However, for any given center, the percentage of patients who healed was greater with rhPDGF than placebo., Conclusions: Wound debridement is a vital adjunct in the care of patients with chronic diabetic foot ulcers.

Objectives: The combination of abdominal aortic aneurysm repair with other intra-abdominal surgery is controversial. Most studies have shown that a variety of procedures can be performed at the same time as an aneurysm repair with little change in mortality or complication rates. We conducted a retrospective study to determine if aneurysm repair could be safely and effectively combined with radical nephrectomy., Methods: We studied 10 patients who underwent combined abdominal aortic aneurysm repair and radical nephrectomy during a 4-year period. Results from this group were compared to a separate control group of 10 patients who underwent radical nephrectomy alone and another of 12 patients underwent abdominal aortic aneurysm repair alone, during the same time period., Results: The overall mortality was 10% and significant complications occurred in an additional 10% of patients. Minor, self-limiting complications occurred in 30% of patients. There were no aortic graft infections that occurred in the entire series of patients at 18 months of mean follow-up. There were no remarkable differences in the entire series of patients and the combined values in a separate group of control patients who had undergone either procedure alone., Conclusions: Simultaneous radical nephrectomy for presumed renal cell carcinoma can be safely combined with repair of abdominal aortic aneurysm in selected patients.

Cyclic strain is known to influence many aspects of vascular cell biology, including macromolecular biosynthesis, cell proliferation, and cell morphology. The simulation of the cyclic strain associated with the vasculature in situ has been carried out mostly using devices that manipulated flat membranes on which the cells of choice are cultured. The purpose of this work was to create an apparatus wherein cyclic strains consistent with those found in native blood vessels could be applied to intact three-dimensional (tubular) specimens perfused ex vivo. The cyclic strain protocols using our apparatus may be any combination of axial stretch and twist. Concurrently, the perfusion flow and shear stress are controlled as desired. Vessel diameter, intraluminal pressure, volume flow, and regional strain are measured and stored on line. To illustrate the application of the device, we present hemodynamic and kinematic data collected from a human saphenous vein segment perfused under steady-flow conditions while subjected to cyclic stretch and twist.

Purpose: The purpose of this study was to define the clinical features of aortic aneurysms occurring in heart transplant recipients., Methods: Among the 734 patients who have undergone heart transplantation at our institution over the last 14 years, we have identified 12 patients (1.6% incidence) with aortic aneurysms (9 infrarenal, 3 thoracoabdominal), making this the largest reported series of aortic aneurysms (AA) in heart transplant recipients., Results: For nine of the 12 patients with AA (75%), the indication for transplantation was ischemic cardiomyopathy. This indication accounted for only 42% of the overall transplantation group; our data therefore show that the risk of infrarenal AA disease was higher for patients who underwent transplantation for ischemic cardiomyopathy than for other indications (p = 0.02). In two of the patients with thoracoabdominal AA, chronic dissection was identified as the specific AA cause, whereas all of the other patients in the study had nonspecific "atherosclerotic" AAs. All 12 patients were symptom free at the time of initial discovery of the AAs. Two of the patients with infrarenal AA were diagnosed with AAs before transplantation; for the seven remaining patients with infrarenal AAs, the mean time between transplantation and AA discovery was 5.0 years (range 1.2 to 11.8 years). Serial radiologic studies allowed us to determine the AA expansion rate in seven of the 12 patients. This rate varied from 0 to 2.53 cm/yr (mean 1.20 cm/yr; 1.0 cm/yr for infrarenal AA alone). Five patients with infrarenal AA underwent AA repair as the initial treatment. Three others underwent repair after their AAs significantly expanded under observation. Mean AA diameter at the time of repair was 6.9 cm. All three patients with thoracoabdominal AAs died of acute AA rupture before resection could be done, despite their initial asymptomatic state. AA diameters at time of rupture were 3.5, 6.0, and 11 cm. All of the eight patients with AA treated with surgery are alive and well (median follow-up 18 months). The only complication was acute heart transplant rejection, which occurred 11 days after AA repair in one patient., Conclusions: Our data suggest that AA occurrence is more likely in patients who undergo heart transplantation for ischemic heart disease than for other indications. Careful serial radiologic surveillance is warranted in any heart transplant patient with an AA, because of the apparent potential for more rapid AA expansion in this patient population than in patients who do not undergo transplantation. We conclude that early repair of infrarenal AA is indicated because excellent operative results and low morbidity rates can be achieved. An aggressive approach to thoracoabdominal AAs in this group may also be appropriate because of the apparent propensity to lethal rupture, sometimes at relatively small AA size.

Purpose: The purpose of this study was to determine whether the hemodynamic consequences of extracranial carotid disease correlate with the risk of subsequent cerebral infarction., Methods: In 95 patients with symptoms who had greater than or equal to 70% stenosis (31 patients) or who had occlusion (64 patients) of the ipsilateral carotid artery, cerebral blood flow was measured by the stable xenon/computed tomography technique both at baseline and after vasodilatory challenge with intravenous acetazolamide. Patients were stratified into group 1, 43 patients with no more than a 5% decrease in flow in any vascular territory, and group 2, 52 patients with greater than a 5% decrease in one or more vascular territories after an acetazolamide challenge., Results: In group 2, 15 (28.9%) of 52 patients had a new stroke, but only one (2.3%) of 43 patients in group 1 did (p = 0.0005). Of patients with total carotid occlusion 10 (26%) of 38 in group 2 and none (0%) of 26 in group 1 had a new stroke (p = 0.003). Of patients with greater than or equal to 70% stenosis, five (36%) of 14 in group 2 and only one (6%) of 17 in group 1 had a stroke (p = 0.067)., Conclusion: The loss of cerebral reactivity in patients with symptoms who had greater than or equal to 70% carotid stenosis or occlusion is an important predictor of impending cerebral infarction.

Purpose: The purpose of this study was to investigate the efficacy and safety of recombinant human platelet-derived growth factor (rhPDGF-BB) in a double-blind, placebo-controlled, multicenter study of patients with chronic diabetic ulcers., Methods: Patients with chronic, full-thickness, lower-extremity diabetic neurotrophic ulcers of at least 8 weeks' duration, free of necrotic and infected tissue after debridement, and with transcutaneous oxygen tensions of 30 mm Hg or greater were studied. A total of 118 patients were randomized to receive either topical rhPDGF-BB (2.2 micrograms/cm2 of ulcer area) or placebo until the ulcer was completely resurfaced or for a maximum of 20 weeks, whichever occurred first., Results: Twenty-nine (48%) of 61 patients randomized to the rhPDGF-BB group achieved complete wound healing during the study compared with only 14 (25%) of 57 patients randomized to the placebo group (p = 0.01). The median reduction in wound area in the group given rhPDGF-BB was 98.8% compared with 82.1% in the group given placebo (p = 0.09). There were no significant differences in the incidence or severity of adverse events between the rhPDGF-BB and placebo groups., Conclusions: Once-daily topical application of rhPDGF-BB is safe and effective in stimulating the healing of chronic, full-thickness, lower-extremity diabetic neurotrophic ulcers.

Objective: To determine the effectiveness and safety of arginine-glycine-aspartic acid (RGD) peptide matrix in the treatment of diabetic foot ulcers., Research Design and Methods: This randomized placebo-controlled investigator- and patient-blinded prospective multicenter investigation was conducted at three institutional and three private U.S. clinics providing ambulatory care. Sixty-five diabetic patients with chronic full-thickness neurotrophic foot ulcers were enrolled. Six discontinued the study because of adverse events. RGD peptide matrix (Argidene Gel; formerly Telio-Derm Gel) was applied topically twice weekly for up to 10 weeks in patients who otherwise received standard care. Control group patients received topical saline as a placebo plus standard care. The primary method of assessment was the incidence and rate of ulcer closure. All patients enrolled were included in the data analysis., Results: The percentage of patients whose ulcers healed completely in the RGD peptide matrix group (35%; 14 of 40 patients) was over fourfold greater (P = 0.02) than that in the placebo group (8%; 2 of 25 patients). By the study end point (either day of healing or week 10), 30 of 40 (75%) RGD peptide matrix patients had achieved > 50% ulcer closure compared with 12 of 25 (48%) placebo patients (P = 0.03). RGD peptide matrix also significantly (P = 0.03) increased the rate of ulcer closure over the 10 weeks of the study., Conclusions: RGD peptide matrix treatment promoted and accelerated the healing of chronic diabetic foot ulcers to a significant degree.

Proteolytic imbalance may play a role in the pathogenesis of abdominal aortic aneurysms (AAA). CLG4B, which encodes the 92-kDa form of type IV collagenase, is a candidate gene for AAA. We genotyped a polymorphic dinucleotide repeat in the 5' flanking region of CLG4B in 94 unrelated Caucasian controls and in 127 unrelated Caucasian AAA cases. Eight alleles were detected in 188 control chromosomes with an observed heterozygosity of 0.68. There was no significant difference in allele distribution between cases and controls. We genotyped the dinucleotide repeat in 10 CEPH reference pedigrees and performed pairwise linkage analysis with markers on each of the 22 human autosomes. Lod scores between 10.45 and 20.29 were observed with markers spanning chromosome region 20q11.2-q13.1. Further support for assignment of CLG4B to chromosome 20 was provided by analysis of human-rodent somatic cell hybrids. This work describes a highly polymorphic marker in the CLG4B gene and assigns this gene to chromosome 20.

Reversed vertebral blood flow distal to a subclavian obstruction is not uncommon and rarely leads to stroke. A small subgroup of these patients have obstruction in other portions of the extracranial or intracranial circulation, however, and cerebrovascular symptoms are induced by arm exercise, which may decrease regional cerebral blood flow--at times to critical levels--indicating a true "steal" syndrome. We evaluated six patients with symptomatic subclavian steal syndrome using stable xenon with computed tomography cerebral blood flow mapping. A decrease in flow from 13% to 90% in one or more regional vascular territories was found after arm exercise. Patients with a true "steal" syndrome may be at higher risk for stroke. Measuring regional cerebral blood flow may be a means of detecting patients who have a critical loss of flow reserves and who will be symptomatically improved by cerebral revascularization.

Two patients with neck masses were evaluated, one with computed tomography (CT) and the other with magnetic resonance (MR) imaging. Each mass was correctly identified within the carotid sheath. The correct diagnosis-thrombosed cervical carotid aneurysm--was not considered, necessitating unexpected repair of the aneurysm or artery. Although rare, aneurysm of the cervical carotid artery should be considered in the differential diagnosis of a carotid sheath mass between the jugular vein and carotid artery. Peripheral calcification or enhancement on CT scans and a peripheral signal void on MR images are especially suggestive of the diagnosis.