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Objective The incidence of morbidity and mortality for iliac vascular injuries in the literature are likely overestimated owing to associated injuries. Data for isolated iliac vascular injuries are very limited. No large studies have reported the incidence of morbidity for repair versus ligation of isolated iliac vein injuries. Methods Patients in the National Trauma Data Bank (NTDB; 2007-2012) with at least one iliac vascular injury were analyzed. Isolated iliac vessels were defined as cases with Abbreviated Injury Scale severity score of greater than 3 for extraabdominal injuries and an Organ Injury Scale grade of greater than 3 for intraabdominal injuries. Results Overall, 6262 iliac vascular injuries (2809 penetrating, 3453 blunt) were identified in 271,076 patients with abdominal trauma (2.3%). There were 3379 patients (1841 penetrating, 1538 blunt) with isolated iliac vascular injuries (1.2%) and 557 patients (514 penetrating, 43 blunt) with combined iliac artery and vein injuries (0.2%). The 30-day mortality rate was 16.5% for isolated iliac vein injury, 19.3% for isolated iliac artery injury, and 48.7% for combined isolated iliac artery and vein injury. The 30-day mortality rate was 23.4% for isolated iliac vascular injuries compared with 39.0% for nonisolated iliac vascular injuries ( P P = .875), pulmonary embolism (repair, 1.8%; ligation, 0.5%; P = .38), fasciotomy (repair, 9.3%; ligation, 14.6%; P = .094), amputation (repair, 1.8%; ligation, 2.6%; P = .738), acute kidney injury (repair, 5.8%; ligation, 4.7%; P = .627). Multivariate logistic regression demonstrated that ligation of isolated iliac vein injuries had an odds ratio of 2.2 for mortality compared with repair (95% confidence interval, 1.08-4.66). Conclusions Isolated iliac vascular injuries are associated with a high incidence of mortality, especially for combined venous and arterial injury, but mortality is significantly lower than in patients with nonisolated iliac vascular injuries. In patients with isolated iliac vein injuries, mortality was higher in patients who underwent ligation compared with repair; however, the rates of deep venous thrombosis, pulmonary embolism, fasciotomy, amputation, and acute kidney injury were not different between the treatment groups. These data lend credence to the assessment that repair of iliac vein injuries is preferable to ligation whenever feasible.

Objective Traumatic popliteal vascular injuries are associated with the highest risk of limb loss of all peripheral vascular injuries. A method to evaluate the predictors of amputation is needed because previous scores could not be validated. In the present study, we aimed to provide a simplified scoring system (POPSAVEIT [popliteal scoring assessment for vascular extremity injuries in trauma]) that could be used preoperatively to risk stratify patients with traumatic popliteal vascular injuries for amputation. Methods A review of patients sustaining traumatic popliteal artery injuries was performed. Patients requiring amputation were compared with those with limb salvage at the last follow-up. Of these patients, 80% were randomly assigned to a training group for score generation and 20% to a testing group for validation. Significant predictors of amputation (P 0.65 was considered adequate for validation. Results A total of 355 patients were included, with an overall amputation rate of 16%. On multivariate regression analysis, the risk factors independently associated with amputation in the final model were as follows: systolic blood pressure Conclusions The POPSAVEIT score provides a simple and practical method to effectively stratify patients preoperatively into low- and high-risk major amputation categories.

ObjectivePopliteal artery injury has historically led to high amputation rates in both the military and civilian setting. Military and civilian popliteal injury patterns differ in mechanism and severity of injury, prompting us to compare modern management and report differences in outcomes between these two patient groups. We hypothesized that whereas amputation rates may be higher in the military, this would correlate with worse overall injury severity.MethodsMilitary casualties from 2003-2007 with a popliteal artery injury identified from the Joint Theater Trauma Registry were compared retrospectively with civilian patients presenting to a single level I institution from 2002-2009 with popliteal arterial injury. Demographics, mechanism of injury, coinjuries, Injury Severity Score (ISS), Mangled Extremity Severity Scores (MESS), interventions, and secondary amputation rates were reviewed. Descriptive statistics and unpaired t-tests were used to compare data. Statistical significance was P < .05.ResultsThe study group of 110 patients consisted of 46 (41.8%) military and 64 (58.2%) civilians with 48 and 64 popliteal artery injuries, respectively. The military population was younger (28 vs 35 years; P < .004), entirely male (46 [100%] vs 51 [80%]; P < .0001), and had more penetrating injuries (44 [96%] vs 19 [30%]; P < .0001). ISS (18.7 vs 13.9; P < .005) and MESS (7.3 vs 5.1; P < .0001) were higher in the military group. Limb revascularizations in both military and civilian populations were mostly by autogenous bypass (65% vs 77%) followed by primary repair (26% vs 16%), covered stent (0% vs 6%), or other procedure (ligation and/or thrombectomy) (9% vs 1%). Fasciotomy (20 [42%] vs 37 [58%]; P = .14), compartment syndrome (10 [21%] vs 15 [23%]; P = .84), and concomitant venous repair rates (14 [29%] vs 15 [23%]; P = .42) were not different between cohorts. There was no difference in the fracture rate (26 [54%] vs 41 [64%]; P = .43), but the civilian group had a higher rate of dislocation (1 [2%] vs 19 [30%]; P < .0001). Secondary amputation rates were significantly higher in the military (14 [29%] vs 8 [13%]; P < .03).ConclusionsAlthough both civilian and military cohorts have high amputation rates for popliteal arterial injury, the rate of amputation appears to be higher in the military and is associated with a penetrating mechanism of injury primarily from improvised explosive devices resulting in a higher MESS and ISS.

The objective of this report is to describe our experience of pediatric vascular injuries in a U.S. military combat support hospital in Baghdad, Iraq. A retrospective study was designed using Joint Theater Trauma Registry (JTTR) records in order to evaluate the pediatric (age18 years) population presenting with vascular trauma to a combat hospital in Baghdad, Iraq between April 2006 and August 2008. Demographic data comprised casualty, age, gender, and mechanism of injury. Physiologic data included presenting vital signs (rectal temperature, blood pressure, and heart rate), arterial pH, base deficit, hemoglobin (g/dL), and international normalized ratio.Twenty-five children, median age 14 years (range, 5-17 years), median weight 48 kg (range, 15-80 kg) sustained 18 (72%) blast and 7 (28%) gunshot wounds. The mean Injury Severity Score was 25 ± 16.2. The median operative time for the vascular repairs was 189 minutes (range, 41-505 minutes). Patients were tachycardic (mean ± standard deviation, 136 ± 29 bpm), hypotensive (109/63 ± 29/19 mm Hg), and acidemic (pH 7.26 ± 0.07; BD -5.57 ± 5.1 mEq/L) on arrival to the emergency department and were physiologically improved upon admission to the intensive care unit 3 hours later. Repair techniques were ligation (14; 39%), saphenous graft (11; 31%), lateral suture (7; 19%), end anastomosis (2; 5%), patch (1; 3%), and thrombectomy (1; 3%). Twenty-four hour mean transfusion requirements included crystalloid 102 mL/kg (range, 19-253), transfused blood 47 mL/kg (range, 0-119), fresh frozen plasma 14 mL/kg (range, 0-68), and apheresis platelets (1.2 ± 3.68 units). Over a follow-up of 22 ± 5.5 days, the amputation-free survival was 80%.This is the largest reported wartime series to demonstrate in children that damage control resuscitation despite high injury severity permits simultaneous limb salvage.

Objective Important recent data on retrievable inferior vena cava filter (R-IVCF) used in civilian trauma centers suffer from poor follow-up in these transient patients. Because US military casualties can be more easily followed globally, our objective was to further characterize R-IVCF outcomes in a trauma population with improved follow-up. Methods From July 2003 to June 2007, trauma registry records were retrospectively reviewed for US soldiers injured in Iraq and Afghanistan who had R-IVCF placement. Indications, type of filter, complications, outcomes, and retrieval data were analyzed. Results Seventy-two R-IVCFs were placed during the study period. Mean follow-up was 28.0 ± 12.0 months, in 61 (85%) patients. Mean injury severity score (ISS) was 36.3 ± 10.4 and mean patient age was 27.4 ± 6.4 years. Fifty-nine R-IVCFs (82%) were not retrieved due to: death (1, 1.3%), technical failure (2, 2.8%), lost to follow-up (11, 15.2%), or contraindications to retrieval (45, 62.5%). Thirteen R-IVCFs were successfully removed, an overall retrieval rate of 18%. Median dwell time of those removed was 47 days (range, 10-94). IVCF indications were prophylactic in 23 (32%) and therapeutic in 49 (68%) cases. Both retrieval failures were due to incorporation into the caval wall, attempted at 90 and 156 days. Deep vein thromboses at the insertion site or pulmonary embolism following R-IVCF placement or removal were not observed. To date, there have been no reports of IVC stenosis or occlusion. Conclusion R-IVCFs were safely and effectively used in severely injured military trauma patients with high ISS. Despite improved follow-up, overall retrieval remained low, reflecting the civilian experience. Indication, rather than follow-up losses, accounted for the low retrieval rate. Practice patterns for R-IVCF in trauma may need to be re-examined to optimize outcomes.

Background The management of venous trauma remains controversial. Critics of venous repair have cited an increased incidence of associated venous thromboembolic events with this management. We analyzed the current treatment of wartime venous injuries in United States military personnel in an effort to answer this question. Methods From December 1, 2001, to October 31, 2005, all United States casualties with named venous injuries were evaluated. A retrospective review of a clinical database was performed on demographics, mechanism of injury, associated injuries, treatment, outcomes, and venous thromboembolic events. Data were analyzed using the Fisher exact test, analysis of variance, and logarithmic transformation. Results During this 5-year period, 82 patients sustained 103 named venous injuries due to combat operations. All patients were male, with an average age of 27.9 years (range, 20.3-58.3 years). Blast injuries accounted for 54 venous injuries (65.9%), gunshot wounds for 25 (30.5%), and motor vehicle accidents for 3 (3.6%). The venous injury was isolated in 28 patients (34.1%), and 16 (19.5%) had multiple venous injuries. The venous injury in two patients was associated with acute phlegmasia, with fractures in 33 (40.2%), and 22 (28.1%) sustained neurologic deficits. Venous injuries were treated by ligation in 65 patients (63.1%) and by open surgical repair in 38 (36.9%). Postoperative extremity edema occurred in all patients irrespective of method of management. Thrombosis after venous repair occurred in six of the 38 cases (15.8%). Pulmonary emboli developed in three patients, one after open repair and two after ligation (P > .99). Conclusion In the largest review of military venous trauma in more than three decades, we found no difference in the incidence of venous thromboembolic complications between venous injuries managed by open repair vs ligation. Blast injuries of the extremities have caused most of the venous injuries. Ligation is the most common modality of treatment in combat zones. Long-term morbidity associated with venous injuries and their management will be assessed in future follow-up studies.

Purpose: The management of infected femoral artery pseudoaneurysms (IFAPs) is difficult and controversial. Use of synthetic or autologous conduit during arterial revascularization in these cases is complicated by the presence of sepsis and unavailability of autologous venous conduit. We present the results of common femoral artery (CFA) ligation and local drainage with debridement for the treatment of IFAP. Methods: A retrospective chart review of six consecutive patients from 1995 to 1999 who presented with IFAP from intravenous drug abuse was performed. Inpatient records, anesthesia records, and outpatient clinic charts were reviewed. All patients were men with right-sided lesions. All six patients abused heroin, and five (83%) abused heroin and cocaine. All six patients had a duplex ultrasound scan, and five (83%) patients had a digital subtraction angiogram to confirm the clinical diagnosis. Proximal vascular control was achieved retroperitoneally through an oblique suprainguinal incision. After vascular isolation and test clamping of the distal external iliac artery (EIA), the pedal pulses were examined with continuous wave Doppler scan. If a Doppler signal was present, this was followed with CFA ligation and local drainage and debridement of the IFAP. Results: Pain at injection site and fever with chills were present in five (83%) and three (50%) patients, respectively. A pulsatile groin mass and thigh or leg edema were present in five (83%) patients. Three patients (50%) had a palpable pedal pulse, and all six had a Doppler signal over a pedal artery at presentation. The mean white cell count was 15.6 thousand per cubic millimeter (range, 9.2-19.3). All patients had a Doppler signal over a pedal artery after distal EIA/CFA test occlusion and ligation. None of the patients required an amputation, and all six patients regained their preoperative ambulatory status. The mean follow-up period was 25 months. Two patients had mild claudication (5-6 blocks) at 18 months and 2 years after surgery. All six patients received drug rehabilitation, but they admitted to drug abuse after surgery and rehabilitation. Conclusion: CFA ligation and local debridement are safe treatment modalities for IFAP, if there is an intraoperative Doppler signal over a pedal artery during test occlusion of the distal EIA/CFA. CFA ligation avoids the use and therefore the risk of synthetic conduit infection, because there is a high incidence of postoperative drug injection despite aggressive drug rehabilitation. (J Vasc Surg 2001;33:990-3)

Extremity vascular injury during the current war has been defined by anecdotal description and case series. These reports focused on estimation of short-term limb viability and technical description of commonly used adjuncts. Temporary vascular shunting (TVS) has been advocated in current care structures, yet mostly due to war environments, broader statistical scrutiny is lacking. This study's purpose is to provide perspective on TVS's impact on limb salvage, and estimate longer-term freedom from amputation.Data from the Joint Theater Trauma Registry (JTTR), Balad Vascular Registry (BVR), Walter Reed Vascular Registry (WRVR), electronic medical records, and patient interviews were collected on American Troops sustaining extremity vascular injury from June 2003 through December 2007. Those in whom arterial TVS utilization was identified comprise the TVS group. These were compared with controls with similar injury date and anatomic location managed without TVS. Descriptive statistics were employed establishing overall univariate predictors of amputation and comparison between groups. Proportional-hazards modeling, with propensity score adjustment for systemic injury severity and Level 2 care, characterized risk factors of limb loss and effect of TVS. Freedom from amputation was estimated using Kaplan Meier log-rank methods.Cases and controls consisted of 64 and 61 extremity arterial injuries, respectively. Mean follow-up was 22 months (range: 1-54 months). The TVS group was more severely injured (mean injury severity score [ISS]: 18 [SD = 10] TVS vs. 15 [SD = 10] control, P = .05) and more likely to receive Level 2 care (TVS: 26%; control: 10%, P = .02). Overall, a total of 26 amputations occurred (21%). Penetrating blasts, compared with gunshot wounds, were associated with amputation (30% vs. 6%, P = .002). After propensity score adjustment, use of TVS suggested a reduced risk of amputation (relative risk [RR] = 0.47; 95% confidence interval [CI] [0.18-1.19]; P = .11). Venous repair was associated with limb salvage (RR = 0.2; 95% CI [0.04-0.99], P = .05). Associated fracture (RR = 5.0; 95% CI [1.45-17.28], P = .01), and elevated mangled extremity severity score (MESS) ([MESS 5-7] RR = 3.5, 95% CI [0.97-12.36], P = .06; [MESS 8-12] RR = 16.4; 95% CI (3.79-70.79), P.001) predicted amputation. Amputation-free survival was 78% in the TVS group and 77% in the control group at three years (P = .5).Temporary vascular shunting used as a damage control adjunct in management of wartime extremity vascular injury does not lead to worse outcomes. Benefit from TVS is suggested, but not statistically significant. Injury specific variables of venous ligation, associated fracture, and penetrating blast mechanism are associated with amputation. Amputation-free survival after vascular injury in Operation Iraqi Freedom is 79% at three years. Further studies to statistically define any possible benefits of TVS are needed.

Background Trauma to the head and neck with military munitions often presents with complex multisystem injury patterns. Vascular evaluation typically focuses on the carotid and vertebral arteries; however, trauma to branches of the external carotid artery may also result in devastating complications. Pseudoaneurysms are the most frequent finding on delayed evaluation and can result in life-threatening episodes of rebleeding. Methods Patients evacuated from the Afghanistan and Iraq conflicts with penetrating injury to the face and neck were evaluated by the vascular surgery service to determine the potential for unsuspected vascular injury. Patients with significant penetrating injury underwent computed tomography angiography (CTA) as the initial evaluation and subsequent arteriography in cases where injuries were suspected or metallic fragments produced artifacts obscuring the vasculature. Data on all vascular evaluations were entered prospectively into a database and retrospectively reviewed. Results Between February 2003 and March 2007, 124 patients were evaluated for significant penetrating trauma to the head and neck. Thirteen pseudoaneurysms of the head and neck were found in 11 patients: two in the internal carotid artery, one of the vertebral artery, and 10 involving branches of the external carotid. Seven pseudoaneurysms were symptomatic, of which two presented with episodes of massive bleeding and airway compromise. Seven pseudoaneurysms were treated with coil embolization, 1 with Gelfoam (Upjohn, Kalamazoo, Mich) embolization, 2 with stent grafts, 2 with open repair, and 1 with observation alone. None of the patients undergoing embolization had complications; however, a stent graft of the internal carotid artery occluded early, without stroke. All of the pseudoaneurysms had resolved on follow-up CTA or angiogram. Conclusions Pseudoaneurysms are a common finding in patients with high-velocity gunshot wounds or blast injuries to the head and neck. Most involve branches of the external carotid artery and can be treated by embolization. CTA should be performed on all patients with high-velocity gunshot wounds or in cases of blast trauma with fragmentation injuries of the head and neck.

Diabetes mellitus is a significant risk factor for atherosclerotic peripheral vascular disease. Hyperglycemia and hyperinsulinemia, as encountered in patients with type II diabetes, have been shown to stimulate vascular smooth muscle cell (VSMC) proliferation, a paramount feature in atherosclerosis. Female sex hormones, such as estrogen, have been suggested to inhibit VSMC proliferation. However, the role of progesterone, particularly in patients with diabetes mellitus, has not been examined. Therefore, we studied the effect of progesterone on VSMCs exposed to various concentrations of glucose and insulin.Human infragenicular VSMCs isolated from the tibial arteries of five male patients with diabetes undergoing lower extremity amputation were used. Immunocytochemical studies with confocal microscopy were performed for progesterone receptor identification in these VSMCs. Cells were grown to subconfluence, followed by exposure to deprived media with various glucose (100 and 200 mg/dL) and insulin (no insulin and 100 ng/mL) concentrations. Cells were then additionally exposed to physiologic progesterone (10 ng/mL, progesterone group) and compared with a no-progesterone group. Cell count and methyl-(3)H-thymidine incorporation were used to determine cellular proliferation. Cell count with hemocytometry was performed on day 6. DNA synthesis as reflected through methyl-(3)H-thymidine incorporation was measured at 24 hours.Immunocytochemical studies with confocal microscopy showed cytosolic progesterone receptors. The no-progesterone group showed a significant rise in cell count (P.05) at all concentrations of glucose or insulin compared with the control group containing 100 mg/dL glucose concentration. The no-progesterone group also showed a significant rise in thymidine incorporation (P.05) in the 100 mg/dL glucose-100 ng/mL insulin group and the 200 mg/dL glucose-100 ng/mL insulin group compared with the 100 mg/dL glucose group. In the cell count studies, progesterone significantly inhibited cellular proliferation in several settings. All cell groups cultured with insulin or an elevated glucose concentration showed a significant (P.05) antiproliferative effect when exposed to progesterone. With thymidine incorporation, progesterone showed a similar antiproliferative effect in cells stimulated with glucose or insulin.Significant reductions in cell proliferation as determined with both cell count and thymidine incorporation suggest that progesterone is an inhibitor of VSMC proliferation induced by our in vitro models of hyperglycemia and hyperinsulinemia. Therefore, progesterone may have a protective role against the atherosclerotic changes associated with type II diabetes.

Objective The approach to penetrating trauma of the head and neck has undergone significant evolution and offers unique challenges during wartime. Military munitions produce complex injury patterns that challenge conventional diagnosis and management. Mass casualties may not allow for routine exploration of all stable cervical blast injuries. The objective of this study was to review the delayed evaluation of combat-related penetrating neck trauma in patients after evacuation to the United States. Method From February 2003 through April 2005, a series of patients with military-associated penetrating cervical trauma were evacuated to a single institution, prospectively entered into a database, and retrospectively reviewed. Results Suspected vascular injury from penetrating neck trauma occurred in 63 patients. Injuries were to zone II in 33%, zone III in 33%, and zone I in 11%. The remaining injuries involved multiple zones, including the lower face or posterior neck. Explosive devices wounded 50 patients (79%), 13 (21%) had high-velocity gunshot wounds, and 19 (30%) had associated intracranial or cervical spine injury. Of the 39 patients (62%) who underwent emergent neck exploration in Iraq or Afghanistan, 21 had 24 injuries requiring ligation (18), vein interposition or primary repair (4), polytetrafluoroethylene (PTFE) graft interposition (1), or patch angioplasty (1). Injuries occurred to the carotid, vertebral, or innominate arteries, or the jugular vein. After evacuation to the United States, all patients underwent radiologic evaluation of the head and neck vasculature. Computed tomography angiography was performed in 45 patients (71%), including six zone II injuries without prior exploration. Forty (63%) underwent diagnostic arteriography that detected pseudoaneurysms (5) or occlusions (8) of the carotid and vertebral arteries. No occult venous injuries were noted. Delayed evaluation resulted in the detection of 12 additional occult injuries and one graft thrombosis in 11 patients. Management included observation (5), vein or PTFE graft repair (3), coil embolization (2), or ligation (1). Conclusions Penetrating multiple fragment injury to the head and neck is common during wartime. Computed tomography angiography is useful in the delayed evaluation of stable patients, but retained fragments produce suboptimal imaging in the zone of injury. Arteriography remains the imaging study of choice to evaluate for cervical vascular trauma, and its use should be liberalized for combat injuries. Stable injuries may not require immediate neck exploration; however, the high prevalence of occult injuries discovered in this review underscores the need for a complete re-evaluation upon return to the United States.

A 15-year-old male complained of easy fatigability, leg weakness, and pain on exertion with episodes of syncope while playing baseball. His past medical history was significant for aortic coarctation associated with a congenital bovine hypoplastic aortic arch. A recent arteriogram revealed innominate and left common carotid artery stenosis as well as recurrent coarctation. He had previously undergone three Dacron patch aortoplasties. At the age of 7, he underwent a fourth operation for recurrent coarctation and because of extensive scar tissue in the region of his prior procedures, a left subclavian artery-to-descending aortic bypass was performed. An endovascular repair to deal with the recent recurrence was performed because of prior surgical difficulties. Percutaneous balloon-expandable stents were placed in the aortic coarctation, innominate, and the left common carotid arteries. Postprocedure, ankle brachial indices were >1 and the patient remains asymptomatic after 1 year.

Introduction: Diabetes mellitus is a significant risk factor for atherosclerotic peripheral vascular disease. Hyperglycemia and hyperinsulinemia, as encountered in patients with type II diabetes, have been shown to stimulate vascular smooth muscle cell (VSMC) proliferation, a paramount feature in atherosclerosis. Female sex hormones, such as estrogen, have been suggested to inhibit VSMC proliferation. However, the role of progesterone, particularly in patients with diabetes mellitus, has not been examined. Therefore, we studied the effect of progesterone on VSMCs exposed to various concentrations of glucose and insulin. Methods: Human infragenicular VSMCs isolated from the tibial arteries of five male patients with diabetes undergoing lower extremity amputation were used. Immunocytochemical studies with confocal microscopy were performed for progesterone receptor identification in these VSMCs. Cells were grown to subconfluence, followed by exposure to deprived media with various glucose (100 and 200 mg/dL) and insulin (no insulin and 100 ng/mL) concentrations. Cells were then additionally exposed to physiologic progesterone (10 ng/mL, progesterone group) and compared with a no-progesterone group. Cell count and methyl-3H-thymidine incorporation were used to determine cellular proliferation. Cell count with hemocytometry was performed on day 6. DNA synthesis as reflected through methyl-3H-thymidine incorporation was measured at 24 hours. Results: Immunocytochemical studies with confocal microscopy showed cytosolic progesterone receptors. The no-progesterone group showed a significant rise in cell count (P < .05) at all concentrations of glucose or insulin compared with the control group containing 100 mg/dL glucose concentration. The no-progesterone group also showed a significant rise in thymidine incorporation (P < .05) in the 100 mg/dL glucose-100 ng/mL insulin group and the 200 mg/dL glucose-100 ng/mL insulin group compared with the 100 mg/dL glucose group. In the cell count studies, progesterone significantly inhibited cellular proliferation in several settings. All cell groups cultured with insulin or an elevated glucose concentration showed a significant (P < .05) antiproliferative effect when exposed to progesterone. With thymidine incorporation, progesterone showed a similar antiproliferative effect in cells stimulated with glucose or insulin. Conclusion: Significant reductions in cell proliferation as determined with both cell count and thymidine incorporation suggest that progesterone is an inhibitor of VSMC proliferation induced by our in vitro models of hyperglycemia and hyperinsulinemia. Therefore, progesterone may have a protective role against the atherosclerotic changes associated with type II diabetes. (J Vasc Surg 2002;36:833-8.)