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The biocompatibility of a new material for cardiovascular applications constituted by a poly(ether)urethane (PEtU) and a silicone [polydimethylsiloxane (PDMS)] was evaluated. The achieved material shows properties similar to both polyurethanes and silicones. The material was transformed into porous membranes by a spray-deposition technique. Since any material preparation and manufacturing procedure may introduce some toxicity, in vitro cytotoxicity screening tests were carried out. Human umbilical vein endothelial cells (HUVECs) and a mouse fibroblasts cell line (L929) were cultivated with extracts obtained from materials containing 10, 40 and 100% (w/w) of PDMS. The commercially available Estane 5714-F1® and Cardiothane 51® were used as controls. Extracts were incubated up to 72 hours with HUVECs and L929 cells. The cytotoxic effect was evaluated by light microscopy, cell viability (MTT reduction and neutral red uptake) and proliferation (5-bromo-2′-deoxyuridine incorporation) tests. In vivo studies were carried out using materials containing the same PDMS percentages as for in vitro experiments. The same commercial controls were used. Results obtained with cell culture studies agreed with those obtained in the in vivo experiments and showed that the material preparation and manufacturing procedure do not introduce any toxicity in the products at each PDMS concentration investigated. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the effect of the nutritional supplements Pycnogenol® and Centella asiatica (CA) on atherosclerosis progression in low-risk, asymptomatic subjects with carotid or femoral stenosing plaques., Methods: The study included subjects aged 45-60 with stenosing atherosclerotic plaques (50-60%) in at least one carotid or common femoral bifurcation. Subjects were allocated into 3 groups. In Group 1 (controls), management was based on education, exercise, diet and lifestyle changes. This same management plan was used in the other two groups: Group 2 used Pycnogenol® (100 mg/day), while Group 3 used Pycnogenol® 100 mg/day plus CA (100 mg/day). The follow-up lasted 4 years. Plaque progression was assessed using the ultrasonic arterial score based on arterial wall morphology, considering plaque characteristics and the number of subjects that had cardiovascular events. Oxidative stress was also measured., Results: Of the 413 individuals that were admitted, 391 individuals completed 4 years. Group distribution was comparable. The rate of progression of ultrasound arterial score was significantly lower in the two supplement groups (P<0.05) in comparison with controls suggesting a beneficial effect of Pycnogenol® with a significant difference in favor of the combination (P<0.05). There was a reduction in plaques progression in the supplement groups with the best effects obtained by the combination, considering maximum plaque thickness and length and echogenicity (grey scale median) (P<0.05). Plaques became generally dense (more echogenic) achieving a mixed echogenicity. The occurrence of anginal events was less than 3% in the two supplement groups (in comparison with 6.25% in controls) (P<0.05) with the best results obtained by the combination (P<0.05). The occurrence in myocardial infarctions was significantly lower for the combination (P<0.05). Minor transient ischemic attacks were also less frequent with the supplements with the best results observed with the combination (P<0.05). Events in controls - requiring hospital admission - were globally seen in 16.4% of subjects (minor events) in comparison with 8.9% of subjects using Pycnogenol® and only 3.3% of patients using the combination. At 4 years, oxidative stress in the supplement groups was lower than in controls (P<0.05, with no significant difference between groups 2 and 3)., Conclusions: Pycnogenol® and the combination of Pycnogenol® plus CA reduce the progression of arterial plaques and the progression to clinical stages. The reduction in plaques and clinical progression was associated with a reduction in oxidative stress. The results justify a larger study to define the efficacy of the combination of Pycnogenol® plus CA as a prophylaxis in preclinical atherosclerosis.

Aim: The aim of the study was to evaluate the effect of the nutritional supplements Pycnogenol® and total triterpenic fraction of Centella asiatica (TTFCA) on atherosclerosis progression in low-risk asymptomatic subjects with carotid or femoral stenosing plaques., Methods: This was an observational pilot, substudy of the San Valentino epidemiological cardiovascular study. The study included 824 subjects aged 45-60 without any conventional risk factors who had a stenosing atherosclerotic plaque (>50-60%) in at least one carotid or common femoral bifurcation, allocated into 6 groups: Group 1 (Controls): management was based on education, exercise, diet and lifestyle changes. This same management plan was used in all other groups; group 2: Pycnogenol® 50 mg/day; group 3: Pycnogenol® 100 mg/day; group 4: Aspirin® 100 mg/day or ticlopidine 250 mg/day if intolerant to aspirin; group 5: Aspirin® 100 mg/day and Pycnogenol® 100 mg/day; group 6: Pycnogenol® 100 mg/day plus TTFCA 100 mg/day. The follow-up lasted 42 months. Plaque progression was assessed using the ultrasonic arterial score based on the arterial wall morphology and the number of plaques that progressed and on the number of subjects that had cardiovascular events. A secondary endpoint was to evaluate the changes in oxidative stress at baseline and at 42 months., Results: The ultrasonic score increased significantly in groups 1, 2, and 4 (>1%) but not in groups 3, 5 and 6 (<1%) suggesting a beneficial effect of Pycnogenol® 100 mg. Considering the percent of patients that progressed from class V (asymptomatic) to VI (symptomatic) there was a progression of plaques in 48.09% of controls. In the Pycnogenol® 100 (group 3, 10.4%) and in the Aspirin®+ Pycnogenol® (group 5, 10.68%) progression was half of what observed with antiplatelet agent (group 4, 20.93%); in the TTFCA+ Pycnogenol®group (group 6) progression was 7.4 times lower than in controls; 3.22 times lower than in the antiplatelet agents group (4). Events (hospital admission, specialized care) were observed in 16.03% of controls; there were 8.83% of subjects with events with Pycnogenol® 50 mg and 8% in group 3 (Pycnogenol® 100 mg). In group 4 (antiplatelets), 8.52% of subjects had events; in group 5, 6.87% of subjects had events and in group 6 (TTFCA+ Pycnogenol®) only 4.41% had events (this was the lowest event rate; P<0.05). All treatment groups had a significantly lower event rate (P<0.05) in comparison with controls. Considering treatments groups 2, 3, 5, 6 had a lower number (P<0.05) of subjects in need of cardiovascular management in comparison with controls. The need for risk factor management was higher in controls and lower in group 6 (P<0.05). In groups 2 to 6 the need for risk factor management was lower than in controls (P<0.05). Including all events (hospital admission, need for treatment or for risk management) 51.9% of controls were involved. In the other groups there was a reduction (from a -9.28% reduction in group 2 to a -26% in group 6) (P<0.002). The most important reduction (higher that in all groups; P<0.05) was in group 6. At 42 months, oxidative stress in all the Pycnogenol® groups was less than in the control group. In the combined group of Pycnogenol® and TTFCA the oxidative stress was less than with Pycnogenol® alone (P<0.001)., Conclusion: Pycnogenol® and the combination of Pycnogenol® +TTFCA appear to reduce the progression of subclinical arterial plaques and the progression to clinical stages. The reduction in plaque and clinical progression was associated with a reduction in oxidative stress. The results justify a large, randomized, controlled study to demonstrate the efficacy of the combined Pycnogenol® and TTFCA prophylactic therapy in preclinical atherosclerosis.

Introduction: The aim of this registry evaluation study was to compare, in symptomatic BPH patients, two management plans based on a currently validated standard treatment [defined as the best standard management (BSM)] including or not curcumin (administered as Meriva®) as a further complementary adjuvant element. Signs and symptoms were evaluated using the International Prostate Symptom Score (IPSS). SUBJECTS, METHODS: The study was carried out on a total of 61 subjects. 33 subjects (mean age 58.6;5.3) completed the survey with at least 24 weeks of treatment with Meriva® in association with the BSM. The BSM-alone control group consisted of 28 volunteers of similar age (58.4 years;3.4) and severity of the condition. The range of inclusion age was 55-65. No other clinical or metabolic problems were present. Meriva® was administered at the dosage of 2 tablets/day (2 x 500 mg of Meriva®/day, corresponding to 2 x 100 mg curcumin/day) with a compliance values > 95% as evaluated by the number of tablets used according to medical recommendation. No other drugs or food supplement were used during the study., Results: All IPSS scores, with the exception of the stream weakness score in the BSM group, were improved (p<0.05 vs. inclusion) in both groups. The overall results in the Meriva® group were significantly better than in the BSM-only group (p<0.05). No side effects were recorded. The quality of life improved in both groups, but was significantly better in the Meriva® group (p<0.01). There was also a significantly more important decrease in clinical and subclinical episodes of urinary infections and urinary block in the Meriva® group (p<0.01)., Comments: In patients with BPH, the addition of Meriva® to the standard treatment contributed to the reduction of signs and symptoms of the disease without causing any significant additional side effect. This pilot experience suggests a potential novel clinical application of curcumin, and further studies aimed at selecting the most appropriate dosages and length of treatment as well as the possibility to including longer treatments will, undoubtedly, validate and optimize the role of Meriva® in the management of BPH.

Aim: Intermittent claudication (IC) in peripheral vascular disease is characterized by lower limb pain appearing on effort. Treatment with PGE1 has been successfully used to manage IC patients. This registry has evaluated safety and costs of PGE1 in the management of IC., Methods: In this study a long-term treatment protocol (LTP), a short-term protocol (STP) and an outpatient (OP), "on-demand" treatment have been compared. A treadmill effort test has been used to evaluate walking distance. The follow up for these three protocols was 40 weeks. PGE1 treatment was associated to a risk reduction plan and to an exercise program., Results: The final analysis has included 252 LTP patients, 223 STP patients and 284 OP patients (total 659 valid cases). A group of 171 comparable patients not treated with PGE1 was used for a parallel comparison. Cardiovascular mortality and morbidity has been evaluated in 731 PGE1 patients completing 24 months of follow up. All protocols have been well tolerated. No side effects were observed. The lower cost has been observed for OP patients. In the long term, mortality and morbidity were lower in patients treated with PGE1 in comparison with patients not treated with PGE1., Conclusion: Considering costs and results (increase in walking distance) and improvement in Karnofsky scale the STP plan appears to be better than LTP for IC patients. The OP, "on-demand" treatment offers further improvements. This last treatment plan is simpler; the plan allows better timing for exercise. The treatment can be used even in non-specialized centers.

Aim: This long-term (10-year) study evaluated the safety and efficacy of expanded polytetrafluoroethylene (ePTFE) external valve support (EVS) implants used for external valvuloplasty in the treatment of incompetence of the proximal long saphenous veins., Methods: During a 10-year follow-up, patients with superficial venous disease and venous hypertension due to pure superficial vein incompetence underwent an external valvuloplasty using an EVS with a PTFE suture. Forty-nine patients were included in the EVS group and 47 in the control group. Patients with superficial venous disease and venous hypertension due to pure superficial venous incompetence were randomised into two treatment groups. The first group was treated with what was considered "conventional treatment" (ligation or stripping) and the second with external valvuloplasty with EVS. This report deals with controls treated with ligation as only 6 cases (not mentioned in this report) were treated with stripping. There were no significant differences in the two groups concerning age, sex, or type of venous insufficiency. The procedures focused on only one single limb per patient., Results: 46.9% of limbs treated with EVS developed varices in comparison with 73% in the control group. New surgical procedures (localized ligation) were needed in 32.6% of the EVS patients vs. 55.3% in controls. Sclerotherapy was used in 42% of the EVS patients vs. 72.34% in controls. At 10 years the SFJ was incompetent (reflux) in 2 EVS patients (4%); one after 5 years and one after 7 years. There was no incompetence at the level of the ligated junction in controls. There were 62 incompetent venous sites (1.26 per limb) in the EVS group vs. 96 new incompetent venous sites (2.04 per limb) in controls. In controls 10.63% of the limbs developed minor discolorations and signs due to mild CVI; none was observed in the EVS group. In all ESV implants there was full restoration of competence at 1 year., Conclusion: EVS implants used to correct superficial venous incompetence at 10 years were well tolerated and produced good results on incompetence and on the evolution of varicose veins.

Plant-derived elements used for pharmacological applications constitute an increasing research field. Centella asiatica is widely used mainly as an extract (TECA). Triterpenic fractions, the primary constituents of Centella asiatica, produce a wide range of preventive and therapeutic effects. The modulation of collagen production and deposition in wound healing is of primary importance. TECA is also used to treat several microcirculatory problems, inflammatory skin conditions (leprosy, lupus, varicose ulcers, eczema, atopic dermatitis, psoriasis) and also intestinal problems, fever, amenorrhea and genitourinary conditions. Cognitive functions, anxiety and mental impairment may be also affected by TECA administration. New applications in neurology include nerve growth factor enhancement and applications in neurological degenerative conditions. Interaction with other products is also indicated in this document. The multiplicity of actions of TECA is associated to six important mechanisms, all inter-connected and modulating each other: 1) edema - and capillary filtration - control; 2) a strong antioxidant power, effective on several forms of oxidative stress associated to inflammation or infections and synergic with other antioxidant products; 3) an anti-inflammatory action; 4) a modulation of the collagen production avoiding slower scarring or faster, hyperthrophic scarring and cheloids; 5) a modulating action of local growth factors; 6) a modulation of angiogenesis. This "status" paper - resulting from an expert meeting held in Cobham, Surrey, indicates most of the therapeutic potential of TECA, still to be explored in further studies. The status paper constitutes the basis for a consensus document on TECA to be developed in the next future. This "status" paper opens a new window on an ancient but still partially unexplored product that may become an important value in prevention and treatment of several pre-clinical and risk conditions and in clinically significant disease both as a single products and in association with other 'natural' products.

The degree of integration of biomaterials used in the repair of abdominal wall defects seems to depend upon the structure of the prosthesis. The present investigation evaluates the behaviour in terms of adhesion formation and integration of a new composite prosthesis that could be employed in this clinical application. Full-thickness abdominal wall defects (7 x 5 cm) were created in 16 anaesthetized New Zealand white rabbits and the prosthesis were placed in direct contact with the visceral peritoneum during the experiment. The defects were repaired with a composite prosthesis or pure polypropylene mesh to establish two study groups (n = 8 each). The composite device was constituted by a polypropylene mesh physically attached to a poly(ether)urethane-polydimethylsiloxane laminar sheet. Animals were sacrificed 7, 14, 21 and 30 days after implant and prosthesis/surrounding tissue specimens subjected to light and electron microscopy. Firm adhesions were detected in the polypropylene implants, while they were not present in the composite implants. The excellent behaviour of the composite prosthesis shown in this study warrants further investigation on its use for the repair of abdominal wall defects when a prosthetic device needs to be placed in contact with the intestinal loops.

The aim of this study was to evaluate the prevention of recurrent deep vein thrombosis (R-DVT) with an oral antithrombotic agent (sulodexide) in moderate to high-risk subjects. A group of 405 patients was included into the multicenter registry. Both compression and an exercise program were used as well as a risk-factors control plan. After diagnosis of DVT, patients were treated with oral anticoagulants for 6 months. At the end of this period a coagulation study was made and patients started treatment with oral sulodexide capsules for a period of 24 months. The femoral, popliteal, tibial, and superficial veins were scanned with high-resolution ultrasound at inclusion;scans were repeated at 6, 12, 18, and 24 months. Of the 405 subjects included into the registry 178 in the control group (mean age 52.2; SD 11; M:F=90:88) and 189 in the treatment group (mean age 53.2; SD 10.3; M:F=93:96) completed the analysis period of 24 months. At 6 and 12 months the incidence of R-DVT was lower (p<0.05) in the treatment group. At 24 months the global incidence of R-DVT was 17.9% in the control group and 7.4% in the sulodexide group (p<0.05), 2.42 times lower than in controls. The 2 groups were comparable for age and sex distribution and for the localization of the thrombi at inclusion. Also the 2 groups of dropouts were comparable. In the control group there were 32 recurrent DVTs and 24 subjects lost to follow-up (total of 56) of 202 included subjects (27.7%) in comparison with 28 failures (14 recurrent DVTs and 14 lost subjects) of 203 subjects (13.8%) in the treatment group. This difference was statistically significant. In this analysis the incidence of DVT in controls was 2.07 times higher than in the treatment group subjects. In conclusion sulodexide was effective in reducing recurrent thrombotic events in high-risk subjects.

Purpose: To describe an alternative method of gaining vascular access while preserving blood flow to the profunda femoral artery during combined iliac and superficial femoral artery (SFA) recanalization., Technique: A sheath is introduced through the occluded SFA to reduce the total ischemic time when both the external iliac artery and SFA are obstructed. After iliac stenting and remote endarterectomy of the SFA with stent-graft deployment, blood flow to the profunda is interrupted only briefly when the proximal anastomosis of the femoral endobypass is completed., Conclusions: Sheath insertion into the proximal portion of an occluded SFA can be an effective option in reducing ischemic time when dealing with combined iliac and femoral endovascular procedures.

Purpose: To describe how the combined use of duplex and intravascular ultrasound (IVUS) can assist in the evaluation and treatment of isolated abdominal aortic dissection without need for contrast angiography., Case Report: A 78-year-old man presented with intermittent bilateral buttock and thigh claudication. Duplex ultrasound and contrast-enhanced computed tomography (CT) confirmed a chronic dissection along 3 to 4 cm of the infrarenal abdominal aorta. During Extra Large Palmaz stent implantation, the procedure was based on IVUS images and fluoroscopy without angiography. Both duplex and IVUS images were critical in assessing the type and extent of the lesion to be treated, in guiding the procedure, and in assessing its satisfactory outcome., Conclusions: In selected cases, ultrasound-based imaging modalities can provide most of the information required to accomplish complex aortic procedures.

Basic fibroblast growth factor (bFGF) and platelet-derived growth factor-BB (PDGF-BB) modulate vascular wall cell function in vitro and angiogenesis in vivo. The aim of the current study was to determine how bovine aorta endothelial cells (BAECs) respond to the simultaneous exposure to PDGF-BB and bFGF. It was found that bFGF-dependent BAEC migration, proliferation, and differentiation into tubelike structures on reconstituted extracellular matrix (Matrigel) were inhibited by PDGF-BB. The role played by PDGF receptor alpha (PDGF-Ralpha) was investigated by selective stimulation with PDGF-AA, by blocking PDGF-BB-binding to PDGF-Ralpha with neomycin, or by transfecting cells with dominant-negative forms of the receptors to selectively impair either PDGF-Ralpha or PDGF-Rbeta function. In all cases, PDGF-Ralpha impairment abolished the inhibitory effect of PDGF-BB on bFGF-directed BAEC migration. In addition, PDGF-Ralpha phosphorylation was increased in the presence of bFGF and PDGF, as compared to PDGF alone, whereas mitogen-activated protein kinase phosphorylation was decreased in the presence of PDGF-BB and bFGF compared with bFGF alone. In vivo experiments showed that PDGF-BB and PDGF-AA inhibited bFGF-induced angiogenesis in vivo in the chick embryo chorioallantoic membrane assay and that PDGF-BB inhibited bFGF-induced angiogenesis in Matrigel plugs injected subcutaneously in CD1 mice. Taken together these results show that PDGF inhibits the angiogenic properties of bFGF in vitro and in vivo, likely through PDGF-Ralpha stimulation.

In response to endovascular injury, platelet-derived growth factor-BB (PDGF-BB) and basic fibroblast growth factor (bFGF) are released locally and modulate vascular smooth muscle cells (SMC) proliferation and migration within the vascular wall. The aim of the present in vitro study was to determine how rat aorta SMC respond to the simultaneous exposure to PDGF-BB and bFGF. In a modified Boyden chamber assay bFGF exhibited a dose-dependent effect to inhibit the chemotactic action of PDGF-BB. A comparable result was observed in proliferation assays. In contrast, MIP-1 beta, epidermal growth factor (EGF), fibronectin and acidic FGF (aFGF) did not inhibit the chemotactic effect of PDGF-BB. Denatured bFGF did not exert an inhibitory effect and neutralizing antibodies either to bFGF or to bFGF-receptor abolished the inhibition observed in the presence of bFGF. The role played by PDGF receptor alpha (PDGF-Ralpha) was investigated in PDGF-Ralpha-dominant negative-transfected SMC, by selectively blocking PDGF-BB-binding to PDGF-Ralpha with neomycin, by neutralizing PDGF-Ralpha with a monoclonal antibody and by selectively stimulating PDGF-Ralpha with PDGF-AA; in all cases the effect of bFGF to inhibit PDGF-BB-directed SMC migration was abolished. These in vitro studies show that bFGF significantly inhibits PDGF-BB-induced SMC migration and proliferation and that this effect is mediated by both PDGF-Ralpha and bFGF receptor.

Transfer of the cDNA coding for angiogenic factors represents a novel and promising approach to induce therapeutic angiogenesis and enhance blood flow to ischemic tissues which cannot be revascularized otherwise. This review will focus on therapeutic angiogenesis based on gene transfer techniques for the treatment of myocardial and limb ischemia. The experimental studies demonstrating the angiogenic effect of recombinant growth factors in animal models and in humans, as well as the most promising methods for gene transfer, will be described. Further, gene transfer studies to induce therapeutic angiogenesis will be reviewed to identify critical questions that still need to be answered before gene therapy with angiogenic factors may be considered for routine clinical application.

Endovascular graft repair for aortic aneurysms has led to concerns regarding the healing characteristics of the graft within a thrombus-lined aneurysm and the effect that collateral flow may have on the endoluminal prosthesis and the aneurysm. An anterior aortic patch aneurysm model that preserved collateral arteries was examined and modified to address these issues. In canines (n = 30) a Dacron knitted patch (n = 27) or a rectus fascia patch (n = 3) was sutured into a 3.5-cm anterior aorotomy. Dacron patch aneurysm diameter was an average of 21.8 +/- 2.2 mm (mean canine normal aortic diameter 9.06 +/- 0.79 mm). Canines underwent angiogram, computed tomography, and/or intravascular ultrasound from 1 to 11 weeks later, at which time an endoluminal prosthesis was deployed and followed 30 to 60 days until harvest. Aneurysms accumulated minimal thrombus through the initial 11 weeks. Significant stenosis (mean 21.2% +/- 19%) occurred at aneurysm necks in association with a patch imbrication suture technique (n = 11). Following modification (n = 16), this decreased to a mean of 3.6 +/- 9.7%. Collateral lumbar artery patency was 95% at the time of imaging prior to graft placement. Following successful graft implantation, 16 of 18 aneurysms were filled with thrombus and in most cases the collateral circulation occluded. One of three fascial patch aneurysms ruptured 21 days after creation. This model more accurately depicts abdominal aortic aneurysms with the inherent thrombus and collateral flow that is important when studying aspects of endovascular aortic graft repair.

Using CT scans and intravascular ultrasound (IVUS), aortic, aneurysm neck, and endoluminal graft cross-sectional dimensions were compared in a canine model before and after placement of endoluminal grafts in normal aortas (n = 10) and in artificially constructed abdominal aortic aneurysms (n = 15). Measurement of diameters (n = 83) revealed an average difference or bias between imaging modalities of 0.17 +/- 0.92 mm. Measurements obtained using IVUS were slightly larger than CT values (8.84 +/- 1.0 vs. 8.65 +/- 1.1, p < 0.03) but correlated very well by linear regression analysis (r = 0.948, p < 0.02). Analysis of cross-sectional area (n = 44) revealed an average difference or bias of 7.21 +/- 7.76 mm2 between the two modalities. Again IVUS measurements were larger than CT measurements (65.0 +/- 16.5 vs. 57.9 +/- 11.9, p < 0.001) and linear regression analysis showed less correlation (r = 0.897, p < 0.001). Qualitative assessment of the graft and stent characteristics was more precise using IVUS. Graft folding, stent-aorta interfaces, and thrombus formation were easily identified by IVUS, whereas these more subtle characteristics were missed by CT scanning and arteriography. These studies demonstrate that IVUS measurements were slightly larger than CT values; however, both modalities demonstrate small bias and good correlation. Qualitative analysis of the aneurysmal aorta and endoluminal graft using IVUS is comparable to and in some respects more detailed than measurements from CT scanning and arteriography.

Purpose: This study compares the utility of cineangiography and real-time intravascular ultrasonography (IVUS) in achieving successful deployment of endovascular prostheses., Methods: Five types of 5 cm long, 8 mm internal diameter polyester vascular grafts were secured in the infrarenal aorta of mongrel dogs by 18 mm long Palmaz balloon expandable vascular stents sutured to each end of the prostheses. The endovascular prostheses were delivered by crimping the stents at the ends of the grafts onto a 10 mm outside diameter, 8 cm long polyethylene balloon-dilation catheter. Real-time IVUS of the procedure was provided by a 0.035-inch, 20 MHz imaging element passed through the guide wire lumen in the balloon catheter. Two prostheses of each type were implanted, with one removed at 30 days and the other at 60 days for analysis., Results: At implantation, both angiography and IVUS provided information regarding the choice of site for placement of the device and sizing of the aortic lumen. Real-time IVUS enhanced the information obtained by cineangiography by displaying tomographic views of the vessel anatomy, enabling determination of cross-sectional areas, assessing full stent expansion, and providing information regarding surface topography along the length of the prostheses. Several critical observations were apparent only on IVUS, including incomplete initial stent expansion during two procedures evidenced by pulsation of the aortic wall independent of the stent and movement of unstented segments of thin-walled grafts. Some of these observations led to further interventions at the time of deployment. At death, a comparison of cineangiography, IVUS, and ultrafast computed tomography outlined lumenal continuity and areas of irregularity, thrombus, or narrowing, with IVUS being more sensitive than cineangiography or computed tomography for determining most parameters., Conclusions: We conclude that IVUS is a promising alternative method for precise placement of intravascular grafts.

Inadequate guidance of angioplasty devices limits the endoluminal treatment of high grade atherosclerotic stenoses and total occlusions. Conventional intraluminal ultrasound systems (IVUS) enable lateral cross-sectional imaging of tomographic sections of the vessel wall, but do not offer imaging in front of the catheter. This study describes our initial experience with a forward-looking intravascular ultrasound (FL-IVUS) system (Echoeye, EchoCath, Inc., Princeton, NJ). The acoustic beam from a 25.5 MHz piezoelectric transducer on a 7.5 Fr catheter is mechanically rotated in a forward-looking spiral fashion at 300 cycles/second. Sixty-four axially aligned, cross-sectional, real time images are obtained from a truncated, 60 degree conical volume located 5 to 10 mm from the catheter tip. Luminal dimensions (n = 51) of human cadaveric femoral arteries (cast in agar and submerged in saline) measured by the FL-IVUS were compared to histologic cross-sections of the vessel with a correlation of r = 0.92. FL-IVUS accurately imaged the narrowing lumen in front of total occlusions and the geometry at vessel branches, and identified the location of lesions and the shape and morphology of vessel wall thickness. The 7.5 Fr FL-IVUS over-estimated luminal dimensions in vessels larger than 5 mm. We conclude that FL-IVUS imaging shows promise as a new, accurate method for identifying and characterizing high grade atherosclerotic stenoses and total occlusions, and expands the current capabilities of conventional IVUS systems.

Intravascular ultrasound (IVUS) imaging during peripheral endovascular interventions adds important information regarding the distribution of disease by providing controlled measurements of the cross-sectional area of the vessel lumen and wall prior to and following procedures. IVUS is useful in determining the mechanism and efficacy of balloon angioplasty, in guiding atherectomy devices, and in assuring appropriate placement of intravascular stents. The incorporation of an IVUS element into catheter-based interventional devices may improve the immediate and long-term results of endovascular interventions by decreasing complications from dissection and perforation of the arterial wall. Combined IVUS-stent prototype catheters are being developed to enable imaging and deployment simultaneously. Similar devices are being explored to enhance expedient, precise delivery of endoluminal grafts. Future studies of endovascular techniques should include IVUS, when possible, to accurately quantitative the initial efficacy of devices and to determine the nature and distribution of recurrent lesions.

This report compares the information obtained from arteriography, CT scans, and intravascular ultrasound evaluation of an abdominal aortic aneurysm. The two- and three-dimensional imaging techniques described in this report add information that is redefining the pre- and intraoperative analysis of arterial lesions. The new data may have an influence on the evolution of diagnostic methods and future interventional therapy for vascular disease. This case highlights the developing potential of the methods.

New and exciting vascular imaging technologies are assuming increasingly important roles in the management of vascular disease. Non-invasive modalities such as computerized tomography, magnetic resonance imaging and duplex ultrasound supplement the information obtained by invasive techniques including angiography, angioscopy and intraluminal ultrasound. This paper outlines the modem and developing vascular imaging techniques that are rapidly becoming integral components of advanced diagnostic systems as well as therapeutic devices.

Lung resection for suppurative inflammatory disease is hazardous in children whose small airway diameter precludes the use of standard methods of bronchial separation. A prospective evaluation of the prone position for thoracotomy in 17 children referred for operation with severe inflammatory disease was done. Bronchography showed whole lung bronchiectasis eight, destroyed lung in three, and lobar bronchiectasis five. Pulmonary resections performed with the child prone included left pneumonectomy (nine), right pneumonectomy (four), lingulectomy with lower lobectomy (two), and other lobectomy (two). No endobronchial or intrapleural spillage occurred. One child required reexploration for bleeding and one child developed a postoperative empyema that ultimately caused death. The remaining 16 children were discharged within 8 days of operation, and follow-up of 1 to 18 months records favorable progress.