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ABSTRACT: Stimulated endothelial cells (EC) assume an activated phenotype with pro-inflammatory and prothrombotic features, requiring new gene and protein expression. New protein synthesis in activated EC is largely regulated by transcriptional events controlled by a variety of transcription factors. However, post-transcriptional control of gene expression also influences phenotype and allows the cell to alter protein expression in a faster and more direct way than is typically possible with transcriptional mechanisms. We sought to demonstrate that post-transcriptional control of gene expression occurs during EC activation. Using thrombin-activated EC and a high-throughput, microarray-based approach, we identified a number of gene products that may be regulated through post-transcriptional mechanisms, including the AP-1 transcription factor JunB. Using polysome profiling, cytoplasts and other standard cell biologic techniques, JunB is shown to be regulated at a post-transcriptional level during EC activation. In activated EC, the AP-1 transcription factor JunB, is regulated on a post-transcriptional level. Signal-dependent control of translation may regulate transcription factor expression and therefore subsequent transcriptional events in stimulated EC. J. Cell. Biochem. © 2013 Wiley Periodicals, Inc.
Journal of Cellular Biochemistry 01/2013; · 2.87 Impact Factor
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Matthew T Rondina,
Uyen T Lam,
Robert C Pendleton, Larry W Kraiss,
Nathan Wanner,
Guy A Zimmerman,
John M Hoffman,
Christopher Hanrahan,
Kenneth Boucher,
Paul E Christian,
Regan I Butterfield,
Kathryn A Morton
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ABSTRACT: F-FDG PET has been used for vascular disease, but its role in deep vein thrombosis (DVT) remains prospectively unexplored.
Whole-body F-FDG PET/CT scans were performed in patients 1 to 10 weeks after onset of symptomatic DVT (n = 12) and in control subjects without DVT (n = 24). The metabolic activity (SUVmax) of thrombosed and contralateral nonthrombosed vein segments was determined. The sensitivity and specificity of F-FDG PET/CT for the diagnosis of DVT were determined by receiver operating characteristic curve analyses. In 2 patients with DVT, changes in the metabolic activity of thrombosed vein segments in serial F-FDG PET scans.
The metabolic activity in thrombosed veins [SUVmax, 2.41 (0.75)] was visually appreciable and significantly higher than in nonthrombosed veins in either the contralateral extremity of patients with DVT [SUVmax, 1.09 (0.25), P = 0.007] or control subjects [1.21 (0.22), P < 0.001]. The area under the receiver operating characteristic curve for SUVmax was 0.9773 (P < 0.001), indicating excellent accuracy. An SUVmax threshold of greater than 1.645 was 87.5% sensitive and 100% specific for DVT. Metabolic activity in thrombosed veins correlated significantly with time from DVT symptom onset (decrease in SUVmax of 0.02/d, P < 0.05). Best-fit-line analyses suggested that approximately 84 to 91 days after acute DVT, the maximum metabolic activity of thrombosed veins would return to normal levels.
F-FDG PET/CT is accurate for detecting acute symptomatic, proximal DVT. Metabolic activity in thrombosed veins decreases with time, suggesting that F-FDG PET may be helpful in assessing the age of the clot.
Clinical nuclear medicine 12/2012; 37(12):1139-45. · 3.92 Impact Factor
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ABSTRACT: The resuscitation of patients with ruptured abdominal aortic aneurysms (RAAAs) has not been well studied, and the potential benefit of autotransfusion (AT) is unknown. The increased use of fresh-frozen plasma (FFP) has been associated with decreased mortality rates in trauma patients and may also improve RAAA survival. We explored the influence of intraoperative AT and FFP resuscitation on mortality rates in massively transfused RAAA patients.
A single-center review of RAAA patient records from April 1989 to October 2009 was undertaken. Clinical data and outcomes were studied. Operative and anesthesia records were queried for intraoperative transfusion totals. Massive transfusion was defined as ≥10 units of red blood cells (RBCs) inclusive of AT units.
We identified 151 RAAA patients, of which 89 (60%) received a massive transfusion and comprised the study population. These 89 patients had an in-hospital mortality rate of 44%. Univariate predictors of mortality included increased age, preoperative hypotension, operative blood loss, and crystalloid, RBCs, and FFP volume. AT was used in 85 patients, with an increased ratio of AT:RBC units associated with survival. Mortality was 34% with AT:packed RBCs (PRBC) ≥1 (high AT) and 55% with AT:PRBC of <1 (low AT; P = .04). On multivariate analysis, age > 74 years (P = .03), lowest preoperative systolic blood pressure (SBP) <90 mm Hg (P = .06), blood loss >6 liters (P = .06), and low AT (P = .02) independently predicted mortality. The mean RBC:FFP ratio was similar in those that died (2.7) and in those that lived (2.9; P = .66). RBC:FFP ≤2 (high FFP) was present in 38 (43%) patients, with mortality of 49%. RBC:FFP >2 (low FFP) had 40% mortality (P = .39). RBC:FFP ratios decreased over time from 3.6 (years 1989 to 1999) to 2.2 (years 2000 to 2009; P < .001), but more liberal use of FFP was not associated with decreased mortality (47% vs 41%; P = .56). AT:PRBC ratios were stable over time (range, 1.4-1.2; P = .18).
Greater use of AT but not of FFP was associated with survival in massively transfused RAAA patients. No mortality benefit was seen with increased FFP, but few patients had high FFP transfusion ratios. Further study to identify RAAA patients at risk for massive transfusion should be undertaken and a potentially greater role for AT in RAAA resuscitation investigated.
Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 03/2012; 55(3):688-92. · 3.52 Impact Factor
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ABSTRACT: Translation initiation of eukaryotic mRNAs typically occurs by cap-dependent ribosome scanning mechanism. However, certain mRNAs are translated by ribosome assembly at internal ribosome entry sites (IRESs). Whether IRES-mediated translation occurs in stressed primary human endothelial cells (ECs) is unknown.
We performed microarray analysis of polyribosomal mRNA from ECs to identify IRES-containing mRNAs. Cap-dependent translation was disabled by poliovirus (PV) infection and confirmed by loss of polysome peaks, detection of eukaryotic initiation factor (eIF) 4G cleavage, and decreased protein synthesis. We found that 87.4% of mRNAs were dissociated from polysomes in virus-infected ECs. Twelve percent of mRNAs remained associated with polysomes, and 0.6% were enriched ≥2-fold in polysome fractions from infected ECs. Quantitative reverse transcription-polymerase chain reaction confirmed the microarray findings for 31 selected mRNAs. We found that enriched polysome associations of programmed cell death 8 (PDCD8) and JunB mRNA resulted in increased protein expression in PV-infected ECs. The presence of IRESs in the 5' untranslated region of PDCD8 mRNA, but not of JunB mRNA, was confirmed by dicistronic analysis.
We show that microarray profiling of polyribosomal mRNA transcripts from PV-infected ECs successfully identifies mRNAs whose translation is preserved in the face of stress-induced, near complete cessation of cap-dependent initiation. Nevertheless, internal ribosome entry is not the only mechanism responsible for this privileged translation.
Arteriosclerosis Thrombosis and Vascular Biology 02/2012; 32(4):997-1004. · 6.37 Impact Factor
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Perspectives in Vascular Surgery 08/2011; 23(1):64-5.
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ABSTRACT: Approximately 7-10% of patients with unprovoked VTE will be diagnosed with cancer within 12 months. Although cancer screening has been proposed in these patients, the optimal strategy remains unclear. In a pilot study, we prospectively investigated the use of FDG-PET/CT to screen for occult malignancy in 40 patients with unprovoked VTE.
Patients were initially screened for occult malignancy with a focused history, physical, and laboratory evaluation. Patients underwent whole body FDG-PET/CT and were followed for up to two years for a new diagnosis of cancer. The total costs of using FDG-PET/CT as a comprehensive screening strategy were determined using 2010 Medicare reimbursement rates.
Completion of FDG-PET/CT imaging was feasible and identified abnormal findings requiring additional evaluations in 62.5% of patients. Occult malignancy was evident in only one patient (cancer incidence 2.5%) and FDG-PET/CT imaging excluded malignancy in the remainder of patients. No patients with a negative FDG-PET/CT were diagnosed with malignancy during an average (±SD) follow-up of 449 (±311) days. The use of FDG-PET/CT to screen for occult malignancy added $59,151 in total costs ($1,479 per patient). The majority of these costs were due to the cost of the FDG-PET/CT ($1,162 per patient or 78.5% of total per-patient costs).
FDG-PET/CT may have utility for excluding occult malignancy in patients with unprovoked VTE. The costs of this comprehensive screening strategy were comparable to other screening approaches. Larger studies are needed to further evaluate the utility and cost-effectiveness of FDG-PET/CT as a cancer screening strategy in patients with unprovoked VTE.
Thrombosis Research 07/2011; 129(1):22-7. · 2.44 Impact Factor
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ABSTRACT: Lower extremity injury is common in trauma patients; however, the influence of arterial injury on devastating patient and limb outcomes can be confounded by the presence and physiological derangement of concomitant head or thoracoabdominal injuries. We analyzed isolated lower extremity injuries with an arterial component. Our aim was to elucidate factors associated with mortality and limb loss in this selected population.
We reviewed trauma incidents from the National Trauma Data Bank (2002-2006) containing isolated lower extremity injury codes and a specified infrainguinal arterial injury. Demographics, injury patterns, clinical characteristics, and adverse outcomes (death, amputation) during initial hospitalization were collected. Multivariate logistic regression was used to identify risk factors for limb loss.
There were 651 isolated infrainguinal arterial injuries. Death (18) and early limb loss (42) were studied by mechanism (penetrating, n = 431; blunt, n = 220). Half of the deaths involved injury to the common femoral artery (CFA), and over 80% had injury to the CFA or superficial femoral artery (SFA). Death was three times as frequent in the CFA/SFA than in the popliteal/tibial injuries (P = .02). Penetrating injuries were present in almost 80% of deaths, and most of these were gunshot wounds. Patients who died had mean initial systolic blood pressure of 59.7 mm Hg, and almost 40% had no blood pressure on arrival. Mean initial Glasgow Coma Score was 4.5, and almost 80% arrived with a Glasgow Coma Score of 3 despite the absence of head injury. Twenty-seven above- and 15 below-the-knee amputations were performed. The popliteal artery was injured in half of the amputations, with injury isolated to the popliteal or tibial arteries in about three-quarters. Amputation was twice as frequent in popliteal/tibial than CFA/SFA injury (P = .03) and twice as frequent in blunt than penetrating injury (P = .05). Multiple arterial injuries (odds ratio, 5.2; 95% confidence interval, 1.7-15.6; P = .003), and fracture (odds ratio, 2.2; 95% confidence interval, 1.1-4.2; P = .02) independently predicted amputation, while the presence of nerve injury and soft tissue disruption did not.
Isolated lower extremity trauma with vascular injury has a nearly 10% rate of mortality or limb loss. Mortality is associated with penetrating mechanism and early shock, likely resulting from prehospital proximal arterial hemorrhage. In contrast, early limb loss is more common with blunt distal vascular injury, especially to the popliteal and tibial arteries. Neither nerve nor soft tissue injury predicted limb loss but may result in delayed amputations not captured in this acute outcomes dataset.
Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 06/2011; 53(6):1598-603. · 3.52 Impact Factor
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ABSTRACT: In July 2007, our group began to use a modified conical inferior vena cava filter with additional stabilizing struts designed to reduce tilting of retrievable filters. We analyzed our experience with this modified filter (Cook Medical, Bloomington, Ind) from July 1, 2007 to December 31, 2008 and compared it to our experience with the standard filter (Günther Tulip, Cook Medical, Bloomington, Ind) from January 1, 2006 through December 31, 2008 to determine if adoption of the modified filter reduced tilting and delivered a discernible clinical benefit.
The primary outcome measure was tilt angle after deployment. Secondary outcomes were change in tilt angle between deployment and retrieval (self-centering) and retrieval failure due to inability to engage the filter hook. Measurements were retrospectively determined using the anteroposterior venogram at the time of placement and removal. Tilt angle was defined by the center line of the filter relative to the center line of the inferior vena cava (IVC). Statistical significance was assumed for P ≤ .05.
During the study period, a total of 302 IVC filters were placed. Retrieval was attempted for 85 of 194 (44%) standard filters and 52 of 108 (48%) modified filters. The overall difference in tilt angle (degrees) between the standard (median [interquartile range] = 5 [3, 8]) and modified (5 [3, 8]) filters at the time of placement was not statistically significant (P = .44). Modified filters deployed through a femoral route (8 [4, 11]) had significantly greater tilt angles than modified filters deployed using jugular access (4 [2, 6]; P < .0001). At the time of retrieval, evidence of self-centering was observed more often with modified (32 of 52 [62%]) than standard (36 of 85 [42%]) filters (P = .03). Overall, there were only four failures to retrieve the filter due to excess tilting (standard, 3 of 85 [4%], modified, 1 of 52 [2%]; P = .59).
Overall, tilt angle at insertion did not differ between the modified and standard filters, although more modified filters displayed self-centering. There was no difference between the groups in retrieval failure due to excess tilting. Despite its greater tendency to self-center, we did not recognize a measurable clinical advantage of the modified filter.
Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 10/2010; 52(4):920-4. · 3.52 Impact Factor
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Hansjörg Schwertz,
Sarah Köster,
Walter H A Kahr,
Noemi Michetti,
Bjoern F Kraemer,
David A Weitz,
Robert C Blaylock, Larry W Kraiss,
Andreas Greinacher,
Guy A Zimmerman,
Andrew S Weyrich
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ABSTRACT: Platelets are classified as terminally differentiated cells that are incapable of cellular division. However, we observe that anucleate human platelets, either maintained in suspension culture or captured in microdrops, give rise to new cell bodies packed with respiring mitochondria and alpha-granules. Platelet progeny formation also occurs in whole blood cultures. Newly formed platelets are structurally indistinguishable from normal platelets, are able to adhere and spread on extracellular matrix, and display normal signal-dependent expression of surface P-selectin and annexin V. Platelet progeny formation is accompanied by increases in biomass, cellular protein levels, and protein synthesis in expanding populations. Platelet numbers also increase during ex vivo storage. These observations indicate that platelets have a previously unrecognized capacity for producing functional progeny, which involves a form of cell division that does not require a nucleus. Because this new function of platelets occurs outside of the bone marrow milieu, it raises the possibility that thrombopoiesis continues in the bloodstream.
Blood 05/2010; 115(18):3801-9. · 9.90 Impact Factor
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Journal of Vascular Surgery 05/2008; 47(4):882-5. · 3.21 Impact Factor
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ABSTRACT: The application of endovascular technology for the emergency treatment of traumatic vascular injuries is a new frontier. This study examines recent nationwide use of endovascular therapy in acute arterial traumatic injuries.
This retrospective study used the National Trauma Data Bank (NTDB). Cases with a diagnosis of arterial vascular injury were identified according to the International Classification of Diseases, Ninth Revision, Clinical Modification, and procedure codes for endovascular therapy were selected. A descriptive analysis and multiple regressions were performed to identify variables predictive of outcomes.
From 1994 to 2003, 12,732 arterial injuries were identified. Between 1997 (when the first endovascular repair was recorded in the NTDB) and 2003, 7286 open arterial repairs and 281 endovascular repairs were recorded for an overall utilization rate for endovascular procedures of 3.7%. The yearly number of endovascular procedures registered in the NTDB increased 27-fold, from four in 1997 to 107 in 2003. Use of stents substantially increased from 12 in 2000 to 30 in 2003; endograft use increased from one in 2000 to 37 in 2003. Nearly equal numbers of blunt (n = 134) and penetrating (n = 111) injuries were treated. The injury severity score (median, interquartile range [IRQ]) was significantly lower in patients who underwent an endovascular procedure at 13 (IRQ, 9 to 26) for trauma vs patients requiring an open procedure at 20 (IRQ, 10 to 34; P < .001), a finding corroborated by the lower number of associated injuries in patients undergoing endovascular repair (8.7 +/- 7.2 vs 13.0 +/- 16.1, P < .001). Using multivariable regression to control for differences in injury severity score and associated injuries, mortality was significantly lower for patients undergoing endovascular procedures (odds ratio, 0.18; P = .029) including those with an arterial injury of the torso or head and neck (odds ratio, 0.51, P = .007). Total length of hospital stay also tended to be lower for patients undergoing endovascular procedures by 18% (P = .064).
The use of endovascular therapy in the setting of acute trauma is increasing in a dramatic fashion and is being used to treat a wide variety of vessels injured by blunt and penetrating mechanisms. Endovascular therapy appears to be particularly suitable for patients who present with less severe injuries and greater hemodynamic stability. These preliminary data suggest that the use of endovascular therapy for acute traumatic arterial injuries yields shorter lengths of stay and improved survival.
Journal of Vascular Surgery 01/2008; 46(6):1222-1226. · 3.21 Impact Factor
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ABSTRACT: Cellular phenotype and function is ultimately determined by the synthesis of proteins derived from a genetic blueprint. Control of gene expression occurs at multiple checkpoints, including the transcription of DNA into RNA and the translation of RNA into protein. Translational control mechanisms are important regulators of cellular phenotype, controlling up to 10% of overall cellular gene expression, yet they remain relatively understudied when compared with transcriptional control mechanisms. Specific regulation of protein synthesis from messenger RNA transcripts allows cells to temporally unlink translation from transcription and provides a mechanism for a more rapid response to environmental signals than if transcription were required. We discuss some of the fundamental concepts of translational control, tools for studying it and its relevance to vascular cells, in particular the endothelium.
Journal of Vascular Surgery 07/2007; 45 Suppl A:A8-14. · 3.21 Impact Factor
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ABSTRACT: New activities of human platelets continue to emerge. One unexpected response is new synthesis of proteins from previously transcribed RNAs in response to activating signals. We previously reported that activated human platelets synthesize B-cell lymphoma-3 (Bcl-3) under translational control by mammalian target of rapamycin (mTOR). Characterization of the ontogeny and distribution of the mTOR signaling pathway in CD34+ stem cell-derived megakaryocytes now demonstrates that they transfer this regulatory system to developing proplatelets. We also found that Bcl-3 is required for condensation of fibrin by activated platelets, demonstrating functional significance for mTOR-regulated synthesis of the protein. Inhibition of mTOR by rapamycin blocks clot retraction by human platelets. Platelets from wild-type mice synthesize Bcl-3 in response to activation, as do human platelets, and platelets from mice with targeted deletion of Bcl-3 have defective retraction of fibrin in platelet-fibrin clots mimicking treatment of human platelets with rapamycin. In contrast, overexpression of Bcl-3 in a surrogate cell line enhanced clot retraction. These studies identify new features of post-transcriptional gene regulation and signal-dependant protein synthesis in activated platelets that may contribute to thrombus and wound remodeling and suggest that posttranscriptional pathways are targets for molecular intervention in thrombotic disorders.
Blood 04/2007; 109(5):1975-83. · 9.90 Impact Factor
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ABSTRACT: Aneurysms of the pancreaticoduodenal arteries (PDA) are rare, accounting for <2% of all visceral aneurysms. An association with celiac artery stenosis has been reported. Many present with rupture, and a high mortality can be expected. Treatment is therefore challenging. Arterial ligation, anuerysmectomy, or bypass has been the mainstay of treatment. We recently treated a patient (who had no celiac axis) with a ruptured PDA aneurysm with combined open and endovascular techniques. A 46-year-old man was transferred to our hospital with a 1-day history of abdominal pain and syncope. On admission, an abdominal and pelvis computerized tomographic (CT) scan identified a large mesenteric hematoma, a 1.9 cm PDA aneurysm, and an occluded celiac axis. Mesenteric angiography revealed no active aneurysm leak and a stenotic superior mesenteric artery (SMA) origin. All hepatic blood flow originated from the stenotic SMA via markedly enlarged PDA collaterals. The patient was brought to the operating room, where absence of the celiac axis was confirmed. An aorto-to-proper hepatic and SMA bypass was performed using a bifurcated polyester graft. The next day, the patient was brought to the angiography suite, where the PDA aneurysm was coiled. Postprocedure CT scans confirmed thrombosis of the aneurysm. Ruptured mesenteric artery aneurysms are a challenging problem for the vascular surgeon. PDA aneurysms are rare and often occur in an unfavorable location. There appears to be an association with anatomic anomalies of the mesenteric circulation. Prompt invasive and noninvasive diagnostic studies aid in the definitive management of this often fatal problem. Combined endovascular and open techniques can be used for successful treatment.
Annals of Vascular Surgery 11/2006; 20(6):792-5. · 1.03 Impact Factor
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Hansjörg Schwertz,
Neal D Tolley,
Jason M Foulks,
Melvin M Denis,
Ben W Risenmay,
Michael Buerke,
Rachel E Tilley,
Matthew T Rondina,
Estelle M Harris, Larry W Kraiss,
Nigel Mackman,
Guy A Zimmerman,
Andrew S Weyrich
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ABSTRACT: Tissue factor (TF) is an essential cofactor for the activation of blood coagulation in vivo. We now report that quiescent human platelets express TF pre-mRNA and, in response to activation, splice this intronic-rich message into mature mRNA. Splicing of TF pre-mRNA is associated with increased TF protein expression, procoagulant activity, and accelerated formation of clots. Pre-mRNA splicing is controlled by Cdc2-like kinase (Clk)1, and interruption of Clk1 signaling prevents TF from accumulating in activated platelets. Elevated intravascular TF has been reported in a variety of prothrombotic diseases, but there is debate as to whether anucleate platelets-the key cellular effector of thrombosis-express TF. Our studies demonstrate that human platelets use Clk1-dependent splicing pathways to generate TF protein in response to cellular activation. We propose that platelet-derived TF contributes to the propagation and stabilization of a thrombus.
Journal of Experimental Medicine 11/2006; 203(11):2433-40. · 13.85 Impact Factor
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ABSTRACT: In an effort to reduce cardiovascular mortality, patients with atherosclerotic arterial disease should undergo risk factor modification according to the American Heart Association/American College of Cardiology (AHA/ACC) Secondary Prevention Guidelines (hereafter, Guideline). We assessed compliance with the Guideline in a group of patients seen in a vascular surgery practice.
We evaluated 200 consecutive patients with lower-extremity occlusive disease, cerebrovascular disease, or abdominal aortic aneurysm seen by a university-based vascular surgery practice. The subjects were patients who had been seen previously in our clinic (ESTABLISHED) and new referrals (NEW). Data pertinent to each of the nine AHA/ACC Guideline goals were collected from patient interviews, medication histories, and laboratory records. Compliance with each of the Guideline goals was evaluated. Differences in compliance between ESTABLISHED and NEW patient groups were also compared. We also recorded whether a patient had a previous endovascular or open surgical vascular intervention (EVENT or NO EVENT). Differences in compliance between the EVENT and NO EVENT groups were compared.
Most patients did not achieve the secondary prevention goals recommended in the Guideline. Patients who had a prior vascular intervention (EVENT) were significantly more likely to achieve goals for low-density lipoprotein level (43% vs 23%), and for statin (71% vs 39%), beta-blocker (46% vs 27%), angiotensin-converting enzyme inhibitor (53% vs. 35%), and antiplatelet agent (85% vs. 68%) use (P < .05). ESTABLISHED patients were significantly more likely than NEW patients to have a prior EVENT (87% vs 47%, P < .0005). ESTABLISHED patients were significantly more likely than NEW patients to achieve goals for low-density lipoprotein level, beta-blocker, and statin use; however, these differences were likely due to the higher proportion of EVENT patients in the ESTABLISHED group.
Compliance with the Guideline is suboptimal in patients with atherosclerotic arterial disease. Secondary prevention goals were more often achieved in the EVENT patient group, suggesting that a vascular intervention may lead to increased patient and physician awareness and compliance with the Guideline. A targeted effort towards risk factor modification in patients with atherosclerotic arterial disease could improve compliance with the Guideline and reduce cardiovascular mortality.
Journal of Vascular Surgery 05/2006; 43(4):781-7. · 3.21 Impact Factor
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ABSTRACT: Interactions between platelets and leukocytes link critical thrombotic and inflammatory events that control an array of cardiovascular syndromes. In atherosclerosis alone, inducible gene expression in platelets and leukocytes modulates the initiation and development of vulnerable plaques that increase a patient's risk for acute coronary events. Interruption of gene expression pathways that are triggered when platelets adhere to leukocytes may be a new target for therapeutic intervention. Recent evidence indicates that dipyridamole, an old drug with a diverse history, differentially inhibits gene expression in platelet-leukocyte aggregates by exerting its effect at distinct molecular checkpoints.
Trends in Cardiovascular Medicine 05/2006; 16(3):75-80. · 2.49 Impact Factor
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ABSTRACT: Aortic reconstruction in infants and small children has been reported with Dacron or polytef prosthetic material, hypogastric artery autograft, and saphenous vein autograft. In children, synthetic grafts are limited by a concern for late infection and a lack of potential growth. Available autogenous vessels have a limited length and diameter. Conventional allografts have not been durable. When the entire infrarenal aorta and aortoiliac bifurcation must be replaced, none of the historic options are optimal.
We report 2 cases of infrarenal aorta and aortoiliac bifurcation reconstruction using a new generation of cryopreserved allograft now decellularized for decreased immunogenicity. The branched pulmonary artery allograft is particularly attractive for reconstruction of the aortic bifurcation.
The postoperative course in both cases was uncomplicated. Follow-up with serial abdominal duplex ultrasound has shown no evidence of graft stenosis or calcification at 29 and 32 months, respectively.
The use of commercially available, decellularized, and antigen-reduced allograft offers a nonsynthetic option for replacement of the pediatric abdominal aorta. We chose this novel approach in hopes of reducing the lifetime risk for graft infection and maintaining the potential for graft ingrowth by the child.
Journal of Pediatric Surgery 02/2006; 41(1):226-9. · 1.45 Impact Factor
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ABSTRACT: Primary infections of the aorta are rare. We recently treated a patient who was given a diagnosis of noninfectious aortitis after an extensive work-up, but after clinical deterioration, was found to have a pneumococcal mycotic aneurysm at the time of surgery. The difficulty in distinguishing microbial aortitis from noninfectious chronic periaortitis is discussed as well as the need for frequent surveillance imaging of the aorta if immunosuppression is used to treat the latter entity. The infected aortoiliac segment was ultimately repaired with autologous femoral veins.
Journal of Vascular Surgery 02/2006; 43(1):177-9. · 3.21 Impact Factor
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Larry W Kraiss
Perspectives in Vascular Surgery and Endovascular Therapy 10/2005; 17(3):268-9.
