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Campbell Rogers

Publications and source records attributed to Campbell Rogers.

At least 19 recordsLinked to original sources
PubMed2006

In-stent restenosis and remote coronary lesion progression are coupled in cardiac transplant vasculopathy but not in native coronary artery disease.

OBJECTIVES: The purpose of this study was to describe the clinical, angiographic, and histological features of concomitant in-stent restenosis (ISR) and cardiac allograft vasculopathy (CAV) progression. BACKGROUND: Cardiac allograft vasculopathy is a major challenge to long-term success of heart transplantation. Coronary stenting for CAV is hampered by ISR. METHODS: Quantitative coronary angiography compared late lumen loss (LL) at stented and reference, non-stented segments during 1-year follow-up in post-heart transplant and control atherosclerosis patients. Stented and non-stented arteries with CAV were also obtained post-mortem for immunohistochemical analysis. RESULTS: In 37 stented lesions (25 patients), 1-year binary restenosis occurred in 37.8%. Patients with ISR had higher long-term cardiac death/myocardial infarction rates than patients without ISR (53.8% vs. 9.1%, p = 0.03). In the same 25 patients, 34 CAV lesions with non-significant obstructions were identified as reference controls. After 1 year, patients who developed ISR also had more control lesion LL (0.78 +/- 0.38 mm vs. 0.39 +/- 0.27 mm, p < 0.006) compared to patients without ISR. In the post-transplant patients, in-stent LL was closely coupled to control segment LL (R(2) = 0.63, p < 0.05). Conversely, in native atherosclerosis patients, ISR and remote disease progression were not correlated. Histological staining of stented and control arteries from CAV patients revealed similar pathologies common to ISR and non-intervened CAV segments. CONCLUSIONS: Progression of CAV at non-intervened segments and ISR correlate strongly and share common histopathology. Optimized treatment for patients with aggressive CAV needs to address the widespread nature of this disease, even when it presents as an initially focal lesion.

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PubMed2006

High-density lipoproteins enhance progenitor-mediated endothelium repair in mice.

OBJECTIVE: We quantified endothelial progenitor cell (EPC) engraftment into the endothelial layer as an index of progenitor-mediated endothelial repair. Studies were conducted in C57BL/6J and in apolipoprotein E-deficient (apoE(-/-)) mice. We also investigated the possibility that high-density lipoproteins (HDL) may promote progenitor-mediated endothelial repair. METHODS AND RESULTS: Thoracic aortic sections from C57BL/6J and apoE(-/-) mice were analyzed for evidence of progenitor-derived endothelium as determined by the number of stem cell antigen-1-positive (Sca-1+) cells in the endothelial layer. EPCs (Sca-1+ cells) were significantly increased after endothelial damage induced by lipopolysaccharide (LPS) administration in C57BL/6J mice. The number of EPCs was greater in the aortic endothelium of untreated apoE(-/-) than in untreated C57BL/6J mice and was similar to the number observed in LPS-treated C57BL/6J mice. The number of EPCs in the aortic endothelium of apoE(-/-) mice more than doubled after intravenous infusion of reconstituted HDL. CONCLUSIONS: EPCs are recruited into the aortic endothelial layer of mice in response to an inflammatory insult. EPCs are also increased in the aortic endothelium of untreated apoE(-/-) mice. The observation that number is further increased in apoE(-/-) mice after injection of HDL suggests a role for HDL in promoting progenitor-mediated endothelial repair.

Animals↗
PubMed2006

Platelet glycoprotein IIb/IIIa receptor inhibition as adjunctive treatment during saphenous vein graft stenting: differential effects after randomization to occlusion or filter-based embolic protection.

AIMS: Although embolic protection devices reduce complications during saphenous vein graft (SVG) stenting, adverse events still occur in approximately 10% of patients. IIb/IIIa antagonists have not been proven effective during SVG intervention. We hypothesized that adjunctive use of these agents might enhance the efficacy of embolic protection devices. METHODS AND RESULTS: In the prospective, multicentre FilterWire EX Randomized Evaluation trial, 651 patients undergoing SVG stenting were randomized to either filter-based FilterWire EX or balloon occlusion/aspiration GuardWire embolic protection devices. IIb/IIIa inhibitor use was at the discretion of the investigator, with randomization stratified by intended use. Patients pre-selected for IIb/IIIa inhibitor use (n = 345) had higher baseline risk, with increased 30-day major adverse cardiac events (MACE, 13.0 vs. 8.0%, P = 0.03). GuardWire assigned patients treated with IIb/IIIa inhibitors had higher 30-day MACE compared with those not treated with IIb/IIIa inhibitors (16.0 vs. 6.3%, P = 0.007). In contrast, MACE in high-risk FilterWire patients treated with IIb/IIIa inhibitors were similar to their lower risk, untreated counterparts (9.9 vs. 9.5%, P = 0.89). Multivariable analysis detected a borderline significant (P = 0.056) interaction for lower MACE between FilterWire and IIb/IIIa inhibitor use. Adjustment by the propensity to use IIb/IIIa inhibitors resulted in a significant (P = 0.023) interaction for lower MACE rates. IIb/IIIa inhibition in conjunction with FilterWire was associated with less abrupt closure, no reflow, or distal embolization. CONCLUSION: IIb/IIIa antagonists may improve procedural outcome during SVG stenting in high risk patients, utilizing filter-based embolic protection devices.

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PubMed2006

Six-month outcomes after percutaneous intervention for lesions in aortocoronary saphenous vein grafts using distal protection devices: results from the FIRE trial.

BACKGROUND: The filter-based FilterWire EX (Boston Scientific, Natick, MA) embolic protection system and the GuardWire (Medtronic, Santa Rosa, CA) balloon occlusion and aspiration device have been previously shown to reduce periprocedural complication rates of percutaneous coronary intervention for saphenous vein graft (SVG) disease and are considered the standard of care in this setting. The late clinical course after treatment with these devices has not been reported. METHODS: In the FIRE trial, 651 patients undergoing SVG intervention were randomized to either the FilterWire EX or GuardWire. Six-month rates of the primary end point (composite major adverse cardiac events [MACE]) and its components (death, myocardial infarction [MI], or target vessel revascularization) were studied. RESULTS: MACE at 30 days occurred in 9.9% of patients randomized to the FilterWire EX compared with 11.6% with the GuardWire, P = .53. By 6 months, MACE had increased to 19.3% and 21.9% in FilterWire EX and GuardWire groups, respectively, (relative risk 0.88, 95% CI 0.65-1.19; P = .44). All-cause 6-month mortality in the entire population was 3.5% (3.0% with FilterWire EX vs 4.1% with GuardWire, P = .53, with all deaths occurring after hospital discharge). MI occurred in 12.0% of patients at 6 months (12.1% vs 11.9% with the FilterWire EX and GuardWire, respectively, P = .99), and target vessel revascularization was required in 9.1% (8.2% vs 10.0%, respectively, P = .42). CONCLUSIONS: SVG intervention with the FilterWire EX and GuardWire distal protection devices resulted in similar outcomes at 6 months, although the clinical course after hospital discharge was not benign, with significant rates of death, MI, and repeat intervention.

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PubMed2005

Vascular neointimal formation and signaling pathway activation in response to stent injury in insulin-resistant and diabetic animals.

Diabetes and insulin resistance are associated with increased disease risk and poor outcomes from cardiovascular interventions. Even drug-eluting stents exhibit reduced efficacy in patients with diabetes. We now report the first study of vascular response to stent injury in insulin-resistant and diabetic animal models. Endovascular stents were expanded in the aortae of obese insulin-resistant and type 2 diabetic Zucker rats, in streptozotocin-induced type 1 diabetic Sprague-Dawley rats, and in matched controls. Insulin-resistant rats developed thicker neointima (0.46+/-0.08 versus 0.37+/-0.06 mm2, P=0.05), with decreased lumen area (2.95+/-0.26 versus 3.29+/-0.15 mm2, P=0.03) 14 days after stenting compared with controls, but without increased vascular inflammation (ED1+ tissue macrophages). Insulin-resistant and diabetic rat vessels did exhibit markedly altered signaling pathway activation 1 and 2 weeks after stenting, with up to a 98% increase in p-ERK (anti-phospho ERK) and a 54% reduction in p-Akt (anti-phospho Akt) stained cells. Western blotting confirmed a profound effect of insulin resistance and diabetes on Akt and ERK signaling in stented segments. p-ERK/p-Akt ratio in stented segments uniquely correlated with neointimal response (R2=0.888, P=0.04) in insulin-resistant and type 1 and 2 diabetic rats, but not in lean controls. Transfemoral aortic stenting in rats provides insight into vascular responses in insulin resistance and diabetes. Shifts in ERK and Akt signaling related to insulin resistance may reflect altered tissue repair in diabetes accompanied by a shift in metabolic:proliferative balance. These findings may help explain the increased vascular morbidity in diabetes and suggest specific therapies for patients with insulin resistance and diabetes.

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PubMed2005

Morphometric analysis of particulate debris extracted by four different embolic protection devices from coronary arteries, aortocoronary saphenous vein conduits, and carotid arteries.

Different embolic protection devices have been introduced for endovascular interventions: filters or balloon occlusion and aspiration systems. Despite widening use in a variety of vascular beds and clinical syndromes, little is known about the particulate burden liberated from different vascular beds and caught by different protection devices. We performed histologic and morphometric analyses of particulate debris captured during stenting of degenerated saphenous vein bypass grafts and native coronary arteries during acute myocardial infarction or during elective intervention and carotid arteries to assess the relative performance of different protection devices. We analyzed 232 interventions (90 saphenous vein bypass grafts, 77 native coronary arteries, and 65 carotid arteries) with 4 different devices (65 FilterWires, 99 Interceptors, 41 GuardWires, and 27 Proxis catheters) using the RapidVue particle analyzer. No difference in embolic volume retrieved was demonstrated between devices in saphenous vein bypass grafts and carotid interventions. A smaller volume of particulate debris was retrieved by the GuardWire compared with the FilterWire and the Proxis catheter in native coronary artery interventions. The Interceptor and the GuardWire captured more smaller particles than did the FilterWire or Proxis catheter. During saphenous vein bypass graft or carotid intervention, different embolic protection strategies were performed similarly. In native coronary artery stenting, however, proximal embolic protection retrieved larger amounts of debris than did distal filters or occlusion devices. These data may allow greater tailoring of embolic protection device development and application in specific anatomic locales.

Arterial Occlusive Diseases↗
PubMed2005

Strut position, blood flow, and drug deposition: implications for single and overlapping drug-eluting stents.

BACKGROUND: The intricacies of stent design, local pharmacology, tissue biology, and rheology preclude an intuitive understanding of drug distribution and deposition from drug-eluting stents (DES). METHODS AND RESULTS: A coupled computational fluid dynamics and mass transfer model was applied to predict drug deposition for single and overlapping DES. Drug deposition appeared not only beneath regions of arterial contact with the strut but surprisingly also beneath standing drug pools created by strut disruption of flow. These regions correlated with areas of drug-induced fibrin deposition surrounding DES struts in porcine coronary arteries. Fibrin deposition immediately distal to individual isolated drug-eluting struts was twice as great as in the proximal area and for the stent as a whole was greater in distal segments than proximal segments. Adjacent and overlapping stent struts increased computed arterial drug deposition by far less than the sum of their combined drug load. In addition, drug eluted from the abluminal stent strut surface accounted for only 11% of total deposition, whereas, remarkably, drug eluted from the adluminal surface accounted for 43% of total deposition. Thus, local blood flow alterations and location of drug elution on the strut were far more important in determining arterial wall drug deposition and distribution than were drug load or arterial wall contact with coated strut surfaces. CONCLUSIONS: Simulations that coupled strut configurations with flow dynamics correlated with in vivo effects and revealed that drug deposition occurs less via contact between drug coating and the arterial wall than via flow-mediated deposition of blood-solubilized drug.

Animals↗
PubMed2005

Influence of vessel diameter on the efficacy of distal protection devices during saphenous vein graft intervention.

We sought to determine the influence of vessel diameter on the efficacy of distal protection devices during saphenous vein graft intervention. From the Filterwire EX Randomized Evaluation trial, in which patients who underwent saphenous vein graft stenting were randomized to distal protection with the GuardWire or FilterWire EX, outcomes in 572 patients were examined in vessel size tertiles. The 30-day composite incidence of major adverse cardiac events (MACEs) increased with vessel size and was 6.9%, 9.7%, and 14.9% in the smallest, middle, and largest tertiles, respectively (p = 0.04). MACE rates were relatively vessel size independent for the GuardWire but increased steadily with vessel size with the FilterWire EX. In the smallest tertile, MACEs were reduced by 71% with the FilterWire EX compared with the GuardWire (p = 0.05), with the devices showing similar event rates in the other tertiles.

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PubMed2004

Comparison of the risk of vascular complications associated with femoral and radial access coronary catheterization procedures in obese versus nonobese patients.

In this retrospective review of 5,234 cardiac catheterizations and percutaneous coronary interventions, the rate of vascular complications was highest in extremely thin and morbidly obese patients and lowest in moderately obese patients, consistent with the previously reported "obesity paradox." The use of transradial access and arterial access closure devices was associated with reduced vascular complications in the population of obese patients.

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PubMed2004

Embolic protection with filtering or occlusion balloons during saphenous vein graft stenting retrieves identical volumes and sizes of particulate debris.

BACKGROUND: Distal embolization of plaque particulate liberated during stenting may cause periprocedural complications. The number, size, and volume of debris released during stenting, however, have not been quantified, rendering embolic protection approaches empiric. We used a novel method of microparticle size assessment to measure volume and characterize individual sizes of particles captured by the PercuSurge GuardWire balloon or a vascular filter during saphenous vein graft stenting. METHODS AND RESULTS: Braided nitinol filters (average distal pore size 100 microns) were used in 47 saphenous vein grafts in 44 patients. The PercuSurge GuardWire was used in 17 saphenous vein grafts in 16 patients. Particulate debris was subjected to microparticle size analysis (RapidVue, Beckman Coulter). All samples contained particulate debris. For both filter and GuardWire populations, most particles were <100 microm in longest dimension (87% and 90% of particles, respectively), and the distribution of particle sizes was identical. Total embolic load per lesion for both filters and GuardWire aspirates was also similar: median embolic load per filter was 16 mm3 (range 2 to 84 mm3). Median embolic load per GuardWire was also 16 mm3 (range 7 to 42 mm3). Histopathologic analysis demonstrated that most samples contained plaque elements and platelet-rich thrombus. CONCLUSIONS: During saphenous vein graft interventions, particulate retrieved with a vascular filtering device or an occlusion balloon was similar in amount and character. This supports the notion that unless soluble mediators play an important role in adverse acute clinical events after stenting, the clinical efficacy of filtering devices may be equal to that of occlusion devices.

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