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Sample records for adjunctive balloon angioplasty

  1. Human percutaneous and intraoperative laser thermal angioplasty: initial clinical results as an adjunct to balloon angioplasty.

    PubMed

    Sanborn, T A; Greenfield, A J; Guben, J K; Menzoian, J O; LoGerfo, F W

    1987-01-01

    In this study, the safety and efficacy of percutaneous laser thermal angioplasty as an adjunct to balloon angioplasty were investigated in 13 patients with severe peripheral vascular disease. By means of a novel fiberoptic laser delivery system (Laserprobe) in which argon laser energy is converted to heat in a metallic tip at the end of the fiberoptic fiber, improvement in the angiographic luminal diameter was noted in 14 of 15 femoropopliteal vessels (93%) by delivering 8 to 13 watts of continuous argon laser energy as the Laserprobe was advanced through the lesion. Initial clinical success (indicated by relief of symptoms and increase in Doppler index) for the combined laser and balloon angioplasty procedures was obtained in 12 of 15 vessels (80%), with inadequate balloon dilatation being the limiting factor in three patients. No significant complications of vessel perforation, dissection, pain, spasm, or embolization of debris occurred. Of the 12 patients who had procedures with initial angiographic and clinical success, 10 (83%) were asymptomatic in the initial follow-up period of 1 to 9 months (mean 6 months). Thus, laser thermal angioplasty with a Laserprobe is a safe and effective adjunct to peripheral balloon angioplasty. This technique has the potential to increase the initial success rate of angioplasty for lesions that are difficult or impossible to treat by conventional means. By removing most of the obstructing lesion, this technique may also reduce recurrent stenosis.

  2. Intravascular Ultrasound Imaging of Peripheral Arteries as an Adjunct to Balloon Angioplasty and Atherectomy

    SciTech Connect

    Korogi, Yukunori; Hirai, Toshinori; Takahashi, Mutsumasa

    1996-11-15

    This article reviews many of the applications of intravascular ultrasound (US) imaging for peripheral arterial diseases. In vitro studies demonstrate an excellent correlation between ultrasound measurements of lumen and plaque crossectional area compared with histologic sections. In vivo clinical studies reveal the enhanced diagnostic capabilities of this technology compared with angiography. Intravascular US imaging can provide valuable information on the degree, eccentricity, and histologic type of stenosis before intervention, and on the morphological changes in the arterial wall and the extent of excision after intervention. Intravascular US may also serve as a superior index for gauging the diameter of balloon, stent, laser probe, and/or atherectomy catheter appropriate for a proposed intervention. Significant new insights into the mechanisms of balloon angioplasty and atherectomy have been established by intravascular US findings. Intravascular US imaging has been shown to be a more accurate method than angiography for determining the cross-sectional area of the arterial lumen, and for assessing severity of stenosis. Quantitative assessment of the luminal cross-sectional area after the balloon dilatation should be more accurate than angiography as intimal tears or dissections produced by the dilatation may not be accurately evaluated with angiography. At the present time, intravascular US is still a controversial imaging technique. Outcome studies are currently being organized to assess the clinical value and cost effectiveness of intravascular ultrasound in the context of these interventional procedures.

  3. Balloon angioplasty - short segment

    MedlinePlus

    Angioplasty is a procedure to open narrowed or blocked arteries caused by deposits of plaque. If the blockage is not major, the problem may be corrected by inflating the balloon several times to compact the plaque against the arterial wall, widening the passage for the blood ...

  4. Balloon catheter coronary angioplasty

    SciTech Connect

    Angelini, P.

    1987-01-01

    The author has produced a reference and teaching book on balloon angioplasty. Because it borders in surgery and is performed on an awake patient without circulatory assistance, it is a complex and demanding procedure that requires thorough knowledge before it is attempted. The text is divided into seven sections. The first section describes coronary anatomy and pathophysiology, defines the objectives and mechanisms of the procedure and lists four possible physiologic results. The next section describes equipment in the catheterization laboratory, catheters, guidewires and required personnel. The following section is on the procedure itself and includes a discussion of examination, testing, technique and follow-up. The fourth section details possible complications that can occur during the procedure, such as coronary spasms, occlusion, thrombosis, perforations and ruptures, and also discusses cardiac surgery after failed angioplasty. The fifth section details complex or unusual cases that can occur. The sixth and seventh sections discuss radiation, alternative procedures and the future of angioplasty.

  5. Coronary artery balloon angioplasty - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100160.htm Coronary artery balloon angioplasty - series—Normal anatomy To use the ... slide 9 out of 9 Overview The coronary arteries supply blood to the heart muscle. The right ...

  6. Holmium:YAG laser coronary angioplasty in patients with lesions not ideal for balloon angioplasty

    NASA Astrophysics Data System (ADS)

    Miyazaki, Shunichi; Nonogi, Hiroshi; Goto, Yoichi; Itoh, Akira; Ozono, Keizaburo; Daikoku, Satoshi; Haze, Kazuo

    1993-06-01

    Conventional balloon coronary angioplasty has limitations for application on particular lesions, such as lesions near the left main trunk (LMT), ostial location, and highly eccentric lesions. Hence, efficacy of newly developed Holmium YAG laser coronary angioplasty (HLCA) was assessed for 24 patients with angina. Adjunctive balloon angioplasty was performed for 21 of 24 lesions. Delivered energy ranged from 1.5 to 2.5 watts/pulse and the total exposure time ranged from 6 to 32 seconds. Laser success, defined as 20% reduction of stenotic ratio, was obtained in 16 of 24 (67%) and overall procedural success rate was 92%. Follow up coronary angiography after 3 months showed restenosis in 9 of 19 patients (47%). HLCA is an acutely effective treatment for lesions identified as not ideal for balloon angioplasty. However, angiographical restenosis rate is similar to the conventional balloon angioplasty and a highly calcified complex lesion may not be a candidate for the treatment of HLCA, because of a potential risk of coronary perforation.

  7. Restenosis After Balloon Angioplasty for Cerebral Vasospasm

    SciTech Connect

    Sedat, J. Chau, Y.; Popolo, M.; Gindre, S.; Rami, L.; Orban, J. C.

    2009-03-15

    Transluminal balloon dilatation for symptomatic vasospasm after subarachnoid hemorrhage is effective, and clinical studies have shown that it achieves long-lasting dilatation of spastic cerebral arteries. Delayed arterial renarrowing has not been reported. Here we report the case of a 58-year-old woman who presented asymptomatic and permanent restenosis after angioplasty for cerebral vasospasm.

  8. The safety and feasibility of transradial cutting balloon angioplasty: immediate results, benefits, and limitations.

    PubMed

    Yang, Cheng-Hsu; Guo, G Bih-Fang; Chang, Hsueh-Wen; Yip, Hon-Kan; Hsieh, Kelvin; Fang, Chi-Yung; Chen, Chien-Jen; Hung, Wei-Ching; Hang, Chi-Ling; Wu, Chiung-Jen

    2003-01-01

    Cutting balloon angioplasty can reduce the restenosis rate more than conventional balloon angioplasty, but is traditionally performed through a femoral artery. However, it is not clear how useful a transradial approach would be for cutting balloon angioplasty. This study was conducted to examine the safety, feasibility, and limitations of transradial as opposed to transfemoral cutting balloon angioplasty. From November 1999 to August 2001, 177 patients underwent cutting balloon coronary angioplasty. We compared the success rate, angiographic results, and complication rates of two groups of patients, those undergoing transradial (168 lesions from 153 patients) and those undergoing transfemoral (24 lesions from 24 patients) cutting balloon angioplasty. In both groups of patients who had similar clinical and target lesion characteristics. the percentage of lesions that required balloon predilation (27.4% vs 29.2%). stenting (7.7% vs 4.2%), and adjunct balloon dilation (28.0% vs 33.3%) due to dissection (35.7% vs 33.3%) or suboptimal results were comparable. Both approaches achieved a 100% primary success rate with similar acute gain (2.02 +/- 0.68 mm vs 1.94 +/- 0.70 mm), residual (luminal) diameter stenosis (19.2 +/- 11.7% vs 17.0 +/- 12.7%). proportion of lesions that achieved TIMI 3 flow (98.8% vs 100%), and clinical success rate (98.8% vs 95.8%). However, patients undergoing transradial cutting balloon angioplasty had earlier ambulation and a significantly shorter hospital stay than those undergoing a transfemoral approach (2.80 +/- 2.67 days vs 4.75 +/- 5.44 days, P = 0.005). We conclude that the transradial approach is a feasible and safe alternative to the transfemoral approach for cutting balloon angioplasty. In addition, it offers patients early ambulation and a short hospital stay.

  9. Paget-Schroetter Syndrome Treated with Cutting-Balloon Angioplasty

    SciTech Connect

    Gosling, J.; Nayeemuddin, M.; Cowling, M.; Pherwani, A.; Asquith, J.

    2012-06-15

    Here, a case of Paget-Schroetter Syndrome in a 25-year-old guitar player is reported. After thrombolysis, conventional angioplasty failed to dilate the underlying subclavian stenosis both before and after first-rib excision with scalenus anterior and medius division. For the third attempt at angioplasty, a cutting balloon was used, which immediately produced a good result. Venography at 4-year follow-up showed no restenosis and no functional deficit. This case report demonstrates that cutting-balloon angioplasty may be considered when conventional balloon fails and may have greater durability than conventional balloon angioplasty in the treatment of Paget-Schroetter syndrome.

  10. Cutting-Balloon-Associated Vascular Rupture After Failed Standard Balloon Angioplasty

    SciTech Connect

    Chakraverty, S. Meier, M.A.J.; Aarts, J.C.N.M.; Ross, R.A.; Griffiths, G.D.

    2005-06-15

    The following case reports illustrate a possible complication of vascular rupture when cutting balloon dilatation is performed immediately after failed standard balloon angioplasty to the same diameter. Deferral of the cutting balloon dilatation should be considered in such circumstances.

  11. Does Coronary Stenting Following Balloon Angioplasty Improve Myocardial Fractional Flow Reserve?

    SciTech Connect

    Takeuchi, Masaaki; Himeno, Etsuro

    1998-11-15

    Purpose: Suboptimal distal coronary flow reserve after successful balloon angioplasty has been attributed to angiographically unrecognized inadequate lumen expansion, and adjunct coronary stenting has been shown to improve coronary flow reserve. The aim of this study was to investigate whether myocardial fractional flow reserve (FFRmyo) would increase further after coronary stenting compared with balloon angioplasty alone in the same patient group. Methods: FFRmyo and quantitative coronary angiography were obtained before and after pre-stent balloon dilation, and again after stent placement in 11 patients (7 left anterior descending artery, 3 right coronary artery and 1 left circumflex artery). FFRmyo was calculated as the ratio of Pd/Pa during intracoronary adenosine 5'-triphosphate (50 {mu}g and 20 {mu}g in the left and right coronary arteries, respectively)-induced maximum hyperemia, where Pd represents mean distal coronary pressure measured by a 2.1 Fr infusion catheter and Pa represents mean aortic pressure measured by the guiding catheter. Results: Percent diameter stenosis significantly decreased after balloon angioplasty (74% {+-} 15% vs 37% {+-} 17%, p < 0.001), and decreased further after stent placement (18% {+-} 10%, p < 0.001 vs baseline and balloon angioplasty). FFRmyo after coronary stenting (0.85 {+-} 0.09) was significantly higher than that at baseline (0.51 {+-} 0.16, p < 0.001) and after balloon angioplasty (0.77 {+-} 0.11, p < 0.05). There was a significant correlation between angiographic variables and FFRmyo. The increase in lumen dimensions after coronary stenting was followed by a further significant improvement of FFRmyo. Conclusion: These results suggest that coronary stenting may provide a more favorable functional status and lumen geometry of residual coronary stenosis compared with balloon angioplasty alone.

  12. Finite element analysis of balloon-expandable coronary stent deployment: influence of angioplasty balloon configuration.

    PubMed

    Martin, David; Boyle, Fergal

    2013-11-01

    Today, the majority of coronary stents are balloon-expandable and are deployed using a balloon-tipped catheter. To improve deliverability, the membrane of the angioplasty balloon is typically folded about the catheter in a pleated configuration. As such, the deployment of the angioplasty balloon is governed by the material properties of the balloon membrane, its folded configuration and its attachment to the catheter. Despite this observation, however, an optimum strategy for modelling the configuration of the angioplasty balloon in finite element studies of coronary stent deployment has not been identified, and idealised models of the angioplasty balloon are commonly employed in the literature. These idealised models often neglect complex geometrical features, such as the folded configuration of the balloon membrane and its attachment to the catheter, which may have a significant influence on the deployment of a stent. In this study, three increasingly sophisticated models of a typical semi-compliant angioplasty balloon were employed to determine the influence of angioplasty balloon configuration on the deployment of a stent. The results of this study indicate that angioplasty balloon configuration has a significant influence on both the transient behaviour of the stent and its impact on the mechanical environment of the coronary artery.

  13. Comparison of angioscopic findings between coronary balloon and laser angioplasty

    NASA Astrophysics Data System (ADS)

    Larrazet, Fabrice S.; Dupouy, Patrick J.; Dubois-Rande, Jean Luc; Hirosaka, Akira; Kvasnicka, Jan; Geschwind, Herbert J.

    1994-07-01

    Percutaneous intracoronary angioscopy was used to study the morphological changes occurring in coronary arteries after balloon or laser angioplasty. Angioscopy is thought to provide details on the coronary vessel lumen and the inner wall. Coronary lesion were studied in 44 patients with a 4.5 F Imagecath angioscope before and after each interventional procedure. Balloon and laser angioplasty were performed on 21 (group I) and 23 patients (group II), respectively. There was no difference in age, sex, or angiographic lesion appearance before the procedure between the two groups. Circumferential visualization of the target lesion was successfully completed in 17 group I patients and 19 group II patients. A larger lumen than that observed at control was seen in all 17 dilatation patients and in 13 of the 19 laser patients. Tissue remnants were observed in all balloon and laser patients. Laser irradiation resulted in characteristic sharp edged craters. Dissection was identified in 2 of 19 before versus 9 of 19 patients after balloon angioplasty (p<0.05) and in 0 of 23 before versus 4 of 23 patients after laser angioplasty. Subintimal hemorrhage was observed in 3 of 19 before versus 11 of 19 patients after balloon angioplasty (p<0.05) and in 2 of 23 before versus 4 of 23 patients after laser angioplasty. The frequency of hemorrhage was higher in the post balloon group than in the post laser group (11 of 19 versus 4 of 23, respectively, p<0.02). Angioscopy provides valuable information on lesion morphology after coronary interventions. Balloon dilation results in a high rate of dissection and subintimal hemorrhage. Laser angioplasty is able to ablate obstructing tissue and results in a lower rate of subintimal hemorrhage than balloon dilatation.

  14. Clinical coronary laser balloon angioplasty: effect on ergonovine responsiveness

    NASA Astrophysics Data System (ADS)

    Bowker, Timothy J.; Buller, Nigel P.; Pearson, Morag W.; Rickards, Anthony F.

    1990-07-01

    Laser balloon angioplasty involves delivery of continuous wave Nd-YAG laser energy radially from the surface of a specially designed a.ngioplast.y balloon directly to the luniirial surface of an arterial segment immediately after it.s succeasfu] dilatation by conventional balloon angioplasty, the purpose being to fuse loose flaps and disrupted atheroinatous plaque thermally hack against the arterial wall and to reduce elastic recoil and smooth muscle proliferation, in an attempt to prevent re stenosis . Ergonovirie stimulates arterial wall smooth muscle, normally causes arteries to constrict and is used in the diagnosis of coronary artery spasm. Three patients were treated with laser balloon angioplasty, each receiving 380 3 over 20 seconds (30 W for 5 a, 18 W for 5 s & 14 W for 10 5) . The minimum lumirial diameter of the treated arterial segment was measured angiographically before and after conventional balloon angioplasty, immediately after laser balloon angioplasty and again 1 month later both before and after ergonovine was given. The measurements were (respectively, in mm): 1.03, 1.71, 1.85, 2.37 and 2.37 in patient 1; 0.30, 1.54, 1.85, 2.07 and 2.11 in patient 2; and 0.98, 1.76, 2.27, 2.40 and 2.40 in patient 3. The before and after ergonovire measurements were almost identical, suggesting that laser balloon angioplasty abolishes ergonovine responsiveness for at least up to one month following the procedure, and thus might be of use in treating coronary artery spasm which is resistant to medical therapy.

  15. Cutting Balloon Angioplasty Versus Standard Balloon Angioplasty for Failing Infra-inguinal Vein Grafts: Comparative Study of Short- and Mid-Term Primary Patency Rates

    SciTech Connect

    Vikram, Raghunandan; Ross, Rose A.; Bhat, Rajesh; Griffiths, Gareth D.; Stonebridge, Peter A.; Houston, J. Graeme; Chakraverty, S.

    2007-07-15

    Purpose. To evaluate the results of a recent change in practice in our institution using cutting balloon angioplasty instead of standard balloon angioplasty as the primary treatment for failing infra-inguinal vein bypass grafts. Methods. In this nonrandomized cohort study with a historical control, failing infra-inguinal vein grafts were identified at duplex surveillance or clinical examination. Patients had confirmatory arteriography and balloon angioplasty at the same attendance. Interventions proximal or distal to the graft itself and prosthetic grafts were not included. Patients were entered into a duplex graft surveillance program. Initial assessment of technical success was duplex or improvement 4-6 weeks after the primary angioplasty. Results. Twenty-seven consecutive patients were treated with standard balloon angioplasty, then 11 consecutive patients were treated with cutting balloon angioplasty. Initial technical success was 74% for the standard balloon versus 82% for the cutting balloon. The primary patency rate at 6 months was 16/26 (62%) for standard balloon angioplasty and 8/10 (80%) for cutting balloon angioplasty (p = 0.44). The primary patency rate at 12 months was 9/25 (36%) for standard balloon angioplasty and 5/10 (50%) for cutting balloon angioplasty (p = 0.47). Conclusion. The use of cutting balloons for primary angioplasty of infra-inguinal vein grafts offers no definite advantage over standard balloon angioplasty in this institution or compared with patency rates after standard balloon angioplasty reported elsewhere. Larger multicenter studies would be required to demonstrate whether there was any real difference between the two techniques.

  16. Balloon Angioplasty Optimization: Should We Measure Balloon Volume As Well As Pressure?

    SciTech Connect

    Shehab, M.; Michalis, L. K.; Rees, M. R.

    2008-01-15

    Purpose. To investigate the influence that measurement of balloon volume as a controlled variable in addition to balloon pressure has on the outcome of balloon angioplasty in an experimental model. Methods. One hundred and three segments of explanted normal porcine carotid arteries were obtained. Five were used as controls, and the remaining 98 were subjected to balloon angioplasty with simultaneous measurement of balloon volume and pressure. These arteries were randomized into two groups. In one group the endpoint of the angioplasty was determined by balloon pressure (pressure-limited group, PLG) and in the other group by balloon volume (volume-limited group, VLG). Pressure/volume curves for each procedure were constructed by continuous measurement of both parameters by a purpose-designed computer-controlled inflation device. The diameter of each arterial segment was measured by intravascular ultrasound (IVUS) and the ratio of the inflated balloon to arterial diameter calculated. Arterial appearances after angioplasty were recorded using IVUS. Results. The balloon volumes measured at the endpoint of angioplasty were significantly smaller in the PLG compared with the VLG (p < 0.001). Three types of pressure/volume curves were identified: A, B, and C. In the type A curves, IVUS identified fissures in 28% (17/60) and the examination was normal in 72% (43/60). In the type B curves, IVUS identified fissures in 44% (4/9), dissections in 22% (2/9), and the examination was normal in 33% (3/9). In the type C curves, IVUS identified fissures in 44% (4/9) and dissection in 56% (5/9) with no normal examinations. In undamaged arterial segments a very high correlation was achieved between balloon volume and the balloon/artery ratio (Pearson correlation = -0.979, R{sup 2} = 0.957, p < 0.0001, n = 27). Conclusion. The measurement of pressure and volume during angioplasty enabled the construction of pressure/volume curves that showed deviations from the curves obtained in air. The

  17. Balloon angioplasty of the bilateral renal arteries by Takayasu arteritis with a paclitaxel-eluting balloon.

    PubMed

    Hecht, Tobias; Esmaeili, Anoosh; Behnke-Hall, Kachina

    2015-10-01

    We report about a 12-year-old girl who presented with a blood pressure difference between the extremities with the suspicion of an aortic coarctation. After imaging and laboratory tests, the diagnosis of Takayasu arteritis was made. Owing to persistent arterial hypertension despite medical treatment, we initiated a treatment with a balloon angioplasty of the renal arteries with an eluting balloon.

  18. Angioplasty for Non-arteriosclerotic Renal Artery Stenosis: The Efficacy of Cutting Balloon Angioplasty Versus Conventional Angioplasty

    SciTech Connect

    Tanaka, Ryoichi Higashi, Masahiro; Naito, Hiroaki

    2007-07-15

    Purpose. We examined the efficacy of conventional balloon angioplasty and cutting balloon angioplasty (CBA) for the treatment of non-arteriosclerotic renal artery stenosis (RAS). Materials and Methods. From 1993 to 2005, 20 patients underwent 27 percutaneous transluminal renalangioplasty (PTRA) for non-arteriosclerotic RAS (men: 8, women: 12, 25.5 +/- 2 years old; 16 fibromuscular dysplasia (FMD), 4 Takayasu disease). We evaluated the efficacy of CBA by comparing the rate of initial technical success and surgical conversion. Results. Before the clinical authorization of CBA, three of twelve patients (25 %) underwent surgical bypass due to the failure of PTRA due to the hardness of the lesion. After the approval of cutting balloon, we performed CBA in four cases (2 FMD,2 Takayasu disease) to dilate hard lesions, within which a properly sized balloon could not dilate due to their hardness, or to reduce the risk of local dissection. Initial successes were obtained in all patients (8/8, 100%) and none of the patients underwent surgical conversion. Despite of the good initial result, restenosis was observed in three cases within 6 month (3/4, 75 %). Additional interventions were performed in all patients, then, the severity of the restenotic lesion was found not to be exceeded comparing with the initial lesion. Conclusion. The cutting balloon angioplasty may be safe and useful procedure for hard lesions of RAS caused by non-arteriosclerotic disease? especially fibromuscular dysplasia. The cutting balloon may provide the initial success, but the effect on long-term patency is still controversial.

  19. [Remote results of angioplasty using drug-coated balloons in lesions of the femoropopliteal segment].

    PubMed

    Zatevakhin, I I; Shipovskiĭ, V N; Tursunov, S B; Bagdat'ev, V E; Dzhurakulov, Sh R

    2014-01-01

    The authors analysed the results of balloon angioplasty using paclitaxel-coated balloons (IN.PACT Admiral, Medtronic Inc., USA) in patients with occlusive and stenotic lesions of arteries of the femoropopliteal segment. The Study Group was composed of 30 patients subjected to angioplasty with drug-coated balloons and the Control Group consisted of 32 patients undergoing balloon angioplasty with uncoated balloons. Primary patency of the angioplasty zone within the terms up to 30 months after the intervention using drug-coated balloons amounted to 70% and in the Control Group to 37.5%, with the limb-salvage rate equalling 96.7% and 87.5%, respectively. It was shown that angioplasty using drug-coated balloons in treatment of occlusive and stenotic lesions of femoropopliteal arteries considerably improves the results of treatment at the expense of preventing restenosis of the angioplasty zone both in the short- and long-term periods of follow up.

  20. NOTE: MRI temperature mapping during thermal balloon angioplasty

    NASA Astrophysics Data System (ADS)

    Shmatukha, Andriy V.; Bakker, Chris J. G.

    2006-04-01

    Knowledge on the thermal dose delivered during thermal balloon angioplasty (TBA) is desirable to understand why TBA's outcome varies widely among patients and why it is subject to high restenosis rates. In its conventional implementation, TBA involves injection of a heated medium into a balloon positioned within a stenotic blood vessel. The medium injection causes flow, motion and susceptibility-redistribution artefacts that are devastating to the proton resonance frequency shift (PRFS) technique of MRI temperature mapping. Here, we propose to separate in time medium injection and heating by first inflating a balloon with a medium at an initial temperature, and then by heating the medium up using laser light. The separation is shown to eliminate all the mentioned artefacts and to enable real-time MRI temperature mapping using the PRFS technique. Accurate and reliable temperature maps were acquired in a TBA balloon itself and in the surrounding phantom tissue during heat application.

  1. [Management of aortic recoarctation by transluminal balloon angioplasty in childhood].

    PubMed

    Szatmári, A; Piskóthy, A; Fodor, P; Palik, I; Lozsádi, K

    1997-08-24

    Recoarctation balloon angioplasty is an interventional technique for the treatment of restenosis of the aortic isthmus after surgery. At present it is the treatment of choice prior to surgery. Authors report their experience with the first 30 patients in this country. Age less than 1 year at surgery is considered as a risk factor. The diagnosis of recoarctation was made by noninvasive techniques. Balloon angioplasty was performed in one session with the haemodynamic study. Twenty-nine successful procedures were performed, 1 patient only improved after the dilatation. Systemic hypertension decreased in all, but one patient, the diameter of the narrow segment increased in all patients. No mortality was observed. In one patient femoral artery injury developed without definite impairment of the circulation of the lower extremity. It is concluded, that balloon angioplasty is an effective and safe treatment, carries a lower risk for the patient, than surgery, and hospital stay is shorter. The procedure is cost-effective. Therefore, it is proposed for widespread use in the country.

  2. The development of a pseudo-chamber after balloon pulmonary angioplasty: long-term complications of balloon pulmonary angioplasty.

    PubMed

    Sugiyama, Hisashi; Kise, Hiroaki; Toda, Takako; Hoshiai, Minako

    2016-11-01

    We experienced a rare complication where extravasation developed a pseudo-chamber long after the balloon pulmonary angioplasty for supravalvular pulmonary stenosis. A 3-month-old girl was diagnosed with an anomalous origin of the left coronary artery from the pulmonary artery. She underwent the Takeuchi procedure at 10 months of age. During the follow-up, the supravalvular pulmonary stenosis deteriorated, and was treated by balloon pulmonary angioplasty with the double balloon technique catheter at 6 years of age. Angiography at the main pulmonary artery showed a small amount of extravasation contrast medium after the procedure. Follow-up echocardiography showed a diminished extravasation hemorrhage. Twelve years later, right ventricular enlargement due to pulmonary regurgitation had been observed on echocardiography. In addition, abnormal echo free space was detected at the left posterior of the left atrium. Enhanced computed tomography clearly demonstrated there was an orifice and extent of the pseudo-chamber. Surgical findings revealed a large tear just distal to the coronary tunnel. We speculated that extravasation blood was limited in the perivascular area early after the procedure but eventually reached the non-adhesive oblique pericardial sinus with age. Consequently, pulmonary to oblique pericardial sinus communication was established and looked like a pseudo-chamber long after the procedure. In conclusion, even if extravasation seems to be limited immediately after the balloon pulmonary angioplasty, it could expand for non-adhesive space and could develop a huge blood space like chamber. Long-term careful observation should be necessary for extravasation of pulmonary artery even with surgical adhesion.

  3. Radiofrequency balloon angioplasty. Rationale and proof of principle

    SciTech Connect

    Becker, G.J.; Lee, B.I.; Waller, B.F.; Barry, K.J.; Kaplan, J.; Connolly, R.; Dreesen, R.G.; Nardella, P.

    1988-11-01

    Post-angioplasty restenosis (PARS) in atherosclerotic lesions of medium and small arteries occurs in about one-third of cases in the first year following percutaneous transluminal angioplasty (PTA) (early PARS). PARS includes acute spasm, dissection with reclosure, elastic recoil, fibrocellular proliferative response, and progressive atheromatous disease. Fibrocellular proliferation (possibly initiated by platelet derived growth factor) is felt to be culpable in many cases of early PARS (months). Pharmacologic regimens, stents, and thermal welding of the intimal-medial cracks of PTA are among the interventions being developed to deal with PARS. Radiofrequency (RF) current as a source of thermal energy may be useful in combination with balloon angioplasty to reduce PARS. Ideally, this combination would (1) weld intimal-medial cracks of PTA; (2) mold plaque and normal vessel to increase lumen diameters without creating intimal-medial cracks; and (3) destroy medial smooth muscle cells and multipotential cells (cellular substrate of PARS). Canine in vivo studies have established the feasibility of RF-mediated vascular tissue welding. Human aortic specimens (N = 28) were manually dissected into intima-media and media-adventitia layers. Bipolar RF energy (650 KHz, total 300 J) and mechanical pressure (1 atm) (experimental group, N = 24) or mechanical pressure alone (control group, N = 4) were applied to the reapposed specimen layers in a special chamber. The chamber was modified with a bipolar electrode designed to reproduce that planned for an RF balloon angioplasty catheter. Welding was demonstrated in normal and atherosclerotic treated specimens (23/24 or 96%) but not controls (0/4).

  4. Modeling plaque fissuring and dissection during balloon angioplasty intervention.

    PubMed

    Gasser, T Christian; Holzapfel, Gerhard A

    2007-05-01

    Balloon angioplasty intervention is traumatic to arterial tissue. Fracture mechanisms such as plaque fissuring and/or dissection occur and constitute major contributions to the lumen enlargement. However, these types of mechanically-based traumatization of arterial tissue are also contributing factors to both acute procedural complications and chronic restenosis of the treatment site. We propose physical and finite element models, which are generally useable to trace fissuring and/or dissection in atherosclerotic plaques during balloon angioplasty interventions. The arterial wall is described as an anisotropic, heterogeneous, highly deformable, nearly incompressible body, whereas tissue failure is captured by a strong discontinuity kinematics and a novel cohesive zone model. The numerical implementation is based on the partition of unity finite element method and the interface element method. The later is used to link together meshes of the different tissue components. The balloon angioplasty-based failure mechanisms are numerically studied in 3D by means of an atherosclerotic-prone human external iliac artery, with a type V lesion. Image-based 3D geometry is generated and tissue-specific material properties are considered. Numerical results show that in a primary phase the plaque fissures at both shoulders of the fibrous cap and stops at the lamina elastica interna. In a secondary phase, local dissections between the intima and the media develop at the fibrous cap location with the smallest thickness. The predicted results indicate that plaque fissuring and dissection cause localized mechanical trauma, but prevent the main portion of the stenosis from high stress, and hence from continuous tissue damage.

  5. Balloon angioplasty induces heat shock protein 70 in human blood vessels.

    PubMed

    Kirby, L B; Mondy, J S; Brophy, C M

    1999-09-01

    Balloon angioplasty produces a mechanically induced injury to the blood vessel wall. Heat shock protein 70 (HSP70) is a molecular chaperone whose expression can be induced by chemical or thermal stress. Thus, we hypothesized that the mechanical injury associated with balloon angioplasty would lead to increases in the expression of HSP70 in vascular smooth muscle. Segments of popliteal and trifurcation vessels from above-the-knee amputations were subject to transluminal balloon angioplasty, excised, and placed in organ cultures. Neighboring vessel that was not subjected to balloon angioplasty served as controls. Some vessels were treated with sodium arsenite (positive control, known to induce HSP70 expression). The vessels were homogenized and the proteins were separated by gel electrophoresis and transferred to Immobilon. Western blots with an antibody specific for the inducible form of HSP70 were analyzed by densitometry. Our results showed that HSP70 expression can be induced by the mechanical injury associated with balloon angioplasty in human atherosclerotic vessels.

  6. A helical microwave antenna for welding plaque during balloon angioplasty

    SciTech Connect

    Liu, P.; Rappaport, C.M.

    1996-10-01

    A catheter-based microwave helix antenna has been developed in an attempt to improve the long-term success of balloon angioplasty treatment of arteriosclerosis. When the balloon is inflated to widen vessels obstructed with plaque, microwave power is deposited in the plaque, heating it, and thereby fixing it in place. By optimizing the helix pitch angle and excitation frequency, the antenna radiation pattern can be adjusted to deposit microwave power preferentially in the plaque while avoiding overheating the healthy artery. The optimal power deposition patterns of helical antennas are analytically computed for four-layered concentric and four-layered nonconcentric cylindrical geometries, which model symmetric and asymmetric occluded arteries. Experiments were performed on occluded artery phantom models with a prototype antenna for both symmetric and asymmetric models, which matched the theoretical predictions well, indicating almost complete power absorption in the low-water-content simulated plaque.

  7. Safety and efficacy of low-profile balloons in native coarctation and recoarctation balloon angioplasty for infants.

    PubMed

    Dilawar, Muhammad; El Said, Howaida Galal; El-Sisi, Amal; Ahmad, Zaheer

    2009-05-01

    Background Traditionally, high-profile/high-pressure balloons have been used for angioplasties, whereas low-profile/low-pressure balloons have been used for valvuloplasties. High-profile balloons require larger introducing sheaths, which can be a limiting factor for percutaneous catheter interventions in infants. This report aims to report the author's experience with the efficacy of low-profile balloons using smaller introducing sheaths for coarctation balloon angioplasty in infants. Methods From April 2004 to April 2008, 15 infants, representing both native coarctation and recoarctation indications, underwent coarctation balloon angioplasty and were retrospectively reviewed. The arterial access was achieved using 4-Fr (Cook) introducing sheaths and Tyshak (NuMED, Hallenweg-Netherlands) balloons 5 to 8 mm in diameter for coarctation angioplasty in the study group. Results In this study, 15 infants (7 with native coarctation and 8 with postoperative recoarctation) underwent balloon angioplasty. These infants ranged in age from 2 to 9 months (median, 4 months) and in weight from 3.5 to 10.8 kg (median, 5.7 kg). The peak-to-peak coarctation gradient was reduced from 46.2 +/- 28 mmHg before angioplasty to 10 +/- 8 mmHg afterward (p = 0.001). The angiographic diameter of the coarctation segment was increased from 2.4 +/- 1.0 mm before angioplasty to 5 +/- 0.8 mm afterward (p = 0.001). There were no immediate major or minor complications. During a follow-up period up to 48 months, only one patient from the native coarctation group experienced recoarctation and underwent successful reballooning, and none of the patients experienced aneurysms. Conclusion This study shows that the use of low-profile/low-pressure balloons is an effective treatment for infants. Furthermore, low-profile balloons required smaller introducing sheaths, which provides a clear advantage of minimizing vascular complications with coarctation ballooning in younger infants.

  8. Balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension.

    PubMed

    Lang, Irene; Meyer, Bernhard C; Ogo, Takeshi; Matsubara, Hiromi; Kurzyna, Marcin; Ghofrani, Hossein-Ardeschir; Mayer, Eckhard; Brenot, Philippe

    2017-03-31

    Chronic thromboembolic pulmonary hypertension (CTEPH) is thought to result from incomplete resolution of pulmonary thromboemboli that undergo organisation into fibrous tissue within pulmonary arterial branches, filling pulmonary arterial lumina with collagenous obstructions. The treatment of choice is pulmonary endarterectomy (PEA) in CTEPH centres, which has low post-operative mortality and good long-term survival. For patients ineligible for PEA or who have recurrent or persistent pulmonary hypertension after surgery, medical treatment with riociguat is beneficial. In addition, percutaneous balloon pulmonary angioplasty (BPA) is an emerging option, and promises haemodynamic and functional benefits for inoperable patients. In contrast to conventional angioplasty, BPA with undersized balloons over guide wires exclusively breaks intraluminal webs and bands, without dissecting medial vessel layers, and repeat sessions are generally required. Observational studies report that BPA improves haemodynamics, symptoms and functional capacity in patients with CTEPH, but controlled trials with long-term follow-up are needed. Complications include haemoptysis, wire injury, vessel dissection, vessel rupture, reperfusion pulmonary oedema, pulmonary parenchymal bleeding and haemorrhagic pleural effusions. This review summarises the available evidence for BPA, patient selection, recent technical refinements and periprocedural imaging, and discusses the potential future role of BPA in the management of CTEPH.

  9. Immediate stent recoil in an anastomotic vein graft lesion treated by cutting balloon angioplasty.

    PubMed

    Akkus, Nuri Ilker; Budeepalli, Jagan; Cilingiroglu, Mehmet

    2013-11-01

    Saphenous vein graft (SVG) anastomotic lesions can have significant fibromuscular hyperplasia and may be resistant to balloon angioplasty alone. Stents have been used successfully to treat these lesions. There are no reports of immediate stent recoil following such treatment in the literature. We describe immediate and persistent stent recoil in an anastomotic SVG lesion even after initial and post-deployment complete balloon dilatation of the stent and its successful treatment by cutting balloon angioplasty.

  10. Telescoping of sheaths-an easy technique to facilitate the removal of a stuck ruptured transluminal angioplasty balloon.

    PubMed

    Sequeira, Adrian; Artikov, Shukhrat

    2014-01-01

    Balloon rupture during angioplasty is an uncommon event. The ruptured balloon usually is removed through its introducer sheath without any problems. However, there may be occasions when a ruptured balloon cannot be withdrawn from an access. We describe a simple technique that can be used to extricate a stuck ruptured angioplasty balloon.

  11. Balloon Angioplasty Combined with Primary Stenting Versus Balloon Angioplasty Alone in Femoropopliteal Obstructions: A Comparative Randomized Study

    SciTech Connect

    Vroegindeweij, Dammis; Vos, Louwerens D.; Tielbeek, Alexander V.; Buth, Jacob; Bosch, Harrie C.M. van den

    1997-11-15

    Purpose: To evaluate whether balloon angioplasty combined with stenting (ST) of symptomatic femoropopliteal disease would provide better results compared with balloon angioplasty alone (BA). Methods: Fifty-one patients were randomized between ST (24 patients) and BA (27 patients). Follow-up comprised clinical and hemodynamic assessment and color-flow duplex ultrasound examinations. Results: Residual stenosis ({>=} 30% diameter reduction) occurred in three BA patients, but not in the ST patients. By life-table analysis the cumulative rate of clinical and hemodynamic success after 1 year with ST was 74% (SE 9%) and for those with BA 85% (SE 7%) (p0.25). The primary patency at 1 year assessed by color-flow duplex ultrasound was 62% (SE 9%) for ST-treated patients and 74% (SE 8%) for BA patients (p0.22). Occlusion occurred in five ST patients (21%) compared with two BA patients (7%). Conclusion: ST does not improve clinical and hemodynamic outcome compared with BA. Moreover, the occlusion rate in ST-treated patients is higher.

  12. Angioplasty with drug coated balloons for the treatment of infrainguinal peripheral artery disease.

    PubMed

    Werner, Martin

    2016-09-01

    Restenosis or re-occlusion after femoropopliteal angioplasty or stent implantation is the main limitation of endovascular treatment strategies for peripheral artery disease. Within the last years, balloon catheters with anti-proliferative drug coating on the balloon surface have shown to be associated with higher patency rates compared to plain balloon angioplasty. Thus, drug-coated balloons were gradually adopted in many interventional centres for the treatment of femoropopliteal obstructions. The current review summarises the existing evidence for drug-coated balloons in the infrainguinal vessels and their indication in special lesion cohorts.

  13. Arteriovenous fistula at the site of balloon dilatation complicating femoropopliteal angioplasty

    SciTech Connect

    Malcolm, Paul N.; King, David H.; Crabbe, Ray W.; Taylor, Peter R.; Reidy, John F.

    1997-01-15

    We describe an arteriovenous fistula (AVF) at the site of balloon dilatation immediately after percutaneous transluminal angioplasty (PTA) of the femoropopliteal artery. This occurred during an otherwise uncomplicated angioplasty with a good clinical result. The AVF closed spontaneously within 2 months as monitored by color duplex ultrasound. This uncommon complication of PTA is not widely recognized.

  14. Vessel wall temperature estimation for novel short term thermal balloon angioplasty: study of thermal environment.

    PubMed

    Kaneko, Kenji; Nakatani, Eriko; Futami, Hikaru; Ogawa, Yoshifumi; Arai, Tsunenori; Fukui, Masaru; Shimamura, Satoshi; Kawabata, Takashi

    2005-01-01

    We have been proposing novel thermal balloon angioplasty, photo-thermo dynamic balloon angioplasty (PT-DBA). PTDBA realized <10s short term heating that can prevent surrounding tissue thermal injury and low pressure dilatation that can prevent restenosis in chronic phase. We aim to determine the most efficient heating condition suit to individual symptom with pre-operation thermal simulation. We analyzed the flow dynamics and heat convection inside the balloon, and investigated heat conduction of balloon film to establish the temperature estimation method among vessel wall. Compared with ex vivo temperature measurement experiment, we concluded that the factors need to be considered for the establishment would be the heat conduction of the flow inside PTDB, heat conduction at the balloon film, and contact thermal resistance between the balloon film and vessel wall.

  15. Contralateral Loop Snare Removal of a Ruptured and Entrapped Angioplasty Balloon

    SciTech Connect

    Braun, Michael A.

    1996-11-15

    We describe a technique that extracted a ruptured angioplasty balloon which had become entrapped by a calcified left common iliac artery stenosis. The balloon catheter had been advanced crossover from the right and could not be retracted directly into a sheath across the aortic bifurcation. Therefore, a guidewire was inserted through the balloon catheter and captured by a loop snare advanced from the left femoral artery. The loop snare was also used to free the balloon wings from the stenosis. The balloon was then pulled into a 10 Fr sheath and removed as a unit with the sheath.

  16. Healing after arterial dilatation with radiofrequency thermal and nonthermal balloon angioplasty systems.

    PubMed

    Kaplan, J; Barry, K J; Connolly, R J; Nardella, P C; Hayes, L L; Lee, B I; Waller, B F; Becker, G J; Callow, A D

    1993-01-01

    Thermal balloon angioplasty has been proposed as a means of reducing acute and delayed reclosure of arteries after percutaneous transluminal balloon angioplasty. A radiofrequency (rf) balloon catheter was used to perform thermal balloon angioplasty on canine arteries in vivo. The histologic appearance of rf-treated sites was compared with that of control sites treated by conventional percutaneous transluminal angioplasty. Acutely, rf-treated sites showed a reduced medial cellularity with preservation of internal elastic lamina except at the transitional zone between thermal injury and normal artery, where localized internal elastic lamina disruption was found. Nonthermal sites showed generalized disruption of internal elastic lamina and normal medial cellularity. Both thermal and nonthermal sites displayed a return of intimal cover commencing at 1 to 2 weeks and completed by 4 weeks. Diffuse myointimal hyperplasia appeared by 2 weeks after injury at breaks in the internal elastic lamina along the nonthermal vessels but was localized to the transitional zone in thermal injury sites. In rf-treated vessels, repopulation of the acellular thermally modified media had commenced by 4 weeks, and by 8 weeks the media was diffusely repopulated by spindle-shaped cells resembling smooth muscle cells lying between and aligned with preserved connective tissue laminae. Overall, the distribution and extent of the proliferative response after rf thermal balloon angioplasty were less than those seen after nonthermal balloon angioplasty. Thermal sites, which underwent reintimalization before medial cells returned, were considerably less prone to the development of myointimal hyperplasia. These results suggest that this modality may have beneficial effects on arterial healing after angioplasty.

  17. Uncomplicated moderate coronary artery dissections after balloon angioplasty: good outcome without stenting

    PubMed Central

    Albertal, M; Van Langenhove, G; Regar, E; Kay, I; Foley, D; Sianos, G; Kozuma, K; Beijsterveldt, T; Carlier, S; Belardi, J; Boersma, E; Sousa, J; de Bruyne, B; Serruys, P

    2001-01-01

    OBJECTIVE—To study the relation between moderate coronary dissections, coronary flow velocity reserve (CFVR), and long term outcome.
METHODS—523 patients undergoing balloon angioplasty and sequential intracoronary Doppler measurements were examined as part of the DEBATE II trial (Doppler endpoints balloon angioplasty trial Europe). After successful balloon angioplasty, patients were randomised to stenting or no further treatment. Dissections were graded at the core laboratory by two observers and divided into four categories: none, mild (type A-B), moderate (type C), severe (types D to F). Patients with severe dissections (n = 128) or without available reference vessel CFVR (n = 139) were excluded. The remaining 256 patients were divided into two groups according to the presence (group A, n = 45) or absence (group B, n = 211) of moderate dissection.
RESULTS—Following balloon angioplasty, there was no difference in CFVR between the two groups. At 12 months follow up, a higher rate of major adverse cardiac events was observed overall in group A than in group B (10 (22%) v 23 (11%), p = 0.041). However, the risk of major adverse events was similar in the subgroups receiving balloon angioplasty (group A, 6 (19%) v group B, 16 (16%), NS). Among group A patients, the adverse events risk was greater in those randomised to stenting (odds ratios 6.603 v 1.197, p = 0.046), whereas there was no difference in risk if the group was analysed according to whether the CFVR was < 2.5 or ⩾ 2.5 after balloon angioplasty.
CONCLUSIONS—Moderate dissections left untreated result in no increased risk of major adverse cardiac events. Additional stenting does not improve the long term outcome.


Keywords: coronary dissection; intracoronary Doppler; angioplasty PMID:11454840

  18. Sequential vs. kissing balloon angioplasty for stenting of bifurcation coronary lesions.

    PubMed

    Brueck, Martin; Scheinert, Dierk; Flachskampf, Frank A; Daniel, Werner G; Ludwig, Josef

    2002-04-01

    Coronary angioplasty of bifurcation lesions remains a technical challenge and is believed to result in low procedural success associated with the risk of side-branch occlusion. Furthermore, long-term results are associated with a high rate of reintervention. The aim of the study was to evaluate the immediate and long-term clinical and angiographic results of sequential vs. simultaneous balloon angioplasty (kissing balloon technique) for stenting of bifurcation coronary lesions. Between December 1999 and January 2001, 59 patients underwent coronary angioplasty because of symptomatic bifurcation lesions type III (i.e., side branch originates from within the target lesion of the main vessel, and both main and side branch are angiographically narrowed more than 50%). Twenty-six patients were treated with simultaneous and 33 patients with sequential balloon angioplasty. Main-vessel stent placement was mandatory; side-branch stenting and platelet IIb/IIIa antagonists were allowed at the discretion of the operator. Kissing balloon technique offered no advantage in terms of procedural success or need for repeat target vessel revascularization due to restenosis at 6-month follow-up. Using sequential balloon angioplasty, permanent or transient side-branch compromise rate (TIMI flow < 3) was significantly higher than after kissing balloon technique (33% vs. 0%, respectively; P = 0.003). Major clinical events in-hospital or at 6-month follow-up, however, showed no significant differences. Kissing balloon angioplasty reduces the rate of transient side-branch occlusion compared to sequential PTCA but does not improve immediate or long-term outcome compared to sequential PTCA for stenting of bifurcation lesions.

  19. Treatment of vasospasm by balloon angioplasty: experimental studies and clinical experiences.

    PubMed

    Konishi, Y; Maemura, E; Shiota, M; Hara, M; Takeuchi, K; Saito, I

    1992-06-01

    The vasodilation mode and degree of the invasion caused by balloon angioplasty were experimentally examined. Assessment by light microscopy and scanning electron microscopy demonstrated that the invasion to the implanted arterial wall, taken from a patient who died from vasospasm, was minimized by the use of the balloon under the condition at 1 atm, 10 times for 10 seconds. Furthermore, we applied angioplasty to eight patients who developed severe vasospasm after subarachnoid haemorrhage, and five showed improvement in neurophysiological (transcranial Doppler sonography), neuroradiological, and clinical examinations. In addition, blood vessels obtained from one patient who died 10 days after angioplasty, demonstrated similar findings to those of the experimental studies. It can be said that angioplasty will be one of the effective therapeutic methods to manage vasospasm when it is applied under the conditions mentioned above.

  20. Parametric study for laser hot balloon angioplasty to suppress chronic restenosis: animal experiment

    NASA Astrophysics Data System (ADS)

    Arai, Tsunenori; Miyake, Takayuki; Sakurada, Masami; Miyamoto, Akira; Mizuno, Kyoichi; Kikuchi, Makoto; Nakamura, Haruo; Utsumi, Atsushi; Takeuchi, Kiyoshi

    1996-05-01

    To suppress restenosis after the percutaneous transluminal coronary angioplasty (PTCA), we experimentally investigated the optimum parameter setting on the combination of the balloon temperature and heating duration of our laser hot balloon catheter in rabbit model. The rabbit femoral arteries were treated by our laser hot balloon of 2.5 mm in diameter with various balloon temperatures and durations at the range from 60 to 90 deg., and from 15 to 30 seconds, respectively. The histological examination showed that high temperature (greater than 70 deg.) was necessary to suppress hyperplasia of the vessel in chronic phase. The angiography of pre- and post-treatment and of 2 months after the treatment showed that high temperature with short heating duration (15-30 s) was the best setting for chronic patency of the treated vessels. The laser hot balloon angioplasty with the above mentioned parameter setting might realize significant improvement on chronic patency after PTCA.

  1. Dilatation Mechanism of Balloon Angioplasty in Children: Assessment by Angiography and Intravascular Ultrasound

    SciTech Connect

    Ino, Toshihiro; Kishiro, Masahiko; Okubo, Mataichi; Akimoto, Katsumi; Nishimoto, Kei; Yabuta, Keijiro; Kawasaki, Shiori; Hosoda, Yasuyuki

    1998-03-15

    Purpose: Little information is available about the dilatation mechanism in children. This prospective study aimed to (1) evaluate the dilatation mechanism of balloon angioplasty in children with arterial stenosis, and (2) compare the morphological changes seen by intravascular ultrasound (IVUS) and angiography. Methods: Twenty consecutive patients, who had undergone a total of 23 procedures, were examined before and immediately after balloon angioplasty with a 4.3 Fr, 30 MHz rotational tip IVUS system. The lesions for IVUS study had resulted from coarctation of the aorta in six patients, pulmonary arterial stenosis in five, Blalock-Taussig shunt stenosis in three, subclavian artery stenosis in two, renal artery stenosis in two, coronary artery stenosis in one and ductus arteriosus in one. Results: Four distinctive morphological types were identified: type I with arterial stretching, type IIa with superficial tearing, type IIb with deep intimal-medial tearing, type III with flap formation, and type IV with dissection. The diameter of the narrowest site before and after balloon angioplasty increased significantly from 2.1 {+-} 1.4 mm to 4.6 {+-} 3.4 mm (p < 0.001). Eighteen of the 23 angioplasty procedures (78%) were considered to be successful, with a dilatation ratio of more than 50%. In most patients with successful dilatation, non-stretch mechanisms such as tearing, flap formation, or dissection were found. The positive percent (70%) of non-stretch mechanisms seen by IVUS was significantly higher than the positive findings (39%) by angiography ({chi}{sup 2}= 6.47, p < 0.02). Conclusions: Non-stretch morphology of the arterial wall may be a common mechanism of dilatation after balloon angioplasty in children with arterial stenosis. IVUS is a useful modality for evaluating the effectiveness of balloon angioplasty and the mechanism of dilatation in individual cases.

  2. Effect of low-grade conductive heating on vascular compliance during in vitro balloon angioplasty.

    PubMed

    Mitchel, J F; Fram, D B; Aretz, T A; Gillam, L D; Woronick, C; Waters, D D; McKay, R G

    1994-07-01

    Radiofrequency-powered, thermal balloon angioplasty is a new technique that enhances luminal dilatation with less dissection than conventional angioplasty. The purpose of this study was to assess the effect of radiofrequency heating of balloon fluid on the pressure-volume mechanics of in vitro balloon angioplasty and to determine the histologic basis for thermal-induced compliance changes. In vitro, radiofrequency-powered, thermal balloon angioplasty was performed on 46 paired iliac segments freshly harvested from 23 nonatherosclerotic pigs. Balloon inflations at 60 degrees C were compared to room temperature inflations in paired arterial segments. Intraballoon pressure and volume were recorded during each inflation as volume infusion increased pressure over a 0 to 10 atm range. Pressure-volume compliance curves were plotted for all dilatations. Six segments were stained to assess the histologic abnormalities associated with thermal compliance changes. Radiofrequency heating acutely shifted the pressure-volume curves rightward in 20 of 23 iliac segments compared to nonheated controls. This increase in compliance persisted after heating and exceeded the maximum compliance shift caused by multiple nonheated inflations in a subset of arterial segments. Histologically, heated segments showed increased thinning and compression of the arterial wall, increased medial cell necrosis and altered elastic tissue fibers compared to nonheated specimens. In conclusion, radiofrequency heating of intraballoon fluid to 60 degrees C acutely increases vascular compliance during in vitro balloon angioplasty of nonatherosclerotic iliac arteries. The increased compliance persists after heating and can be greater than the compliance shifts induced by multiple conventional dilatations. Arterial wall thinning and irreversible alteration of elastic tissue fibers probably account for thermal compliance changes.

  3. Reappraisal of primary balloon angioplasty without stenting for patients with symptomatic middle cerebral artery stenosis.

    PubMed

    Okada, Hideo; Terada, Tomoaki; Tanaka, Yuko; Tomura, Nagatsuki; Kono, Kenichi; Yoshimura, Ryo; Shintani, Aki

    2015-01-01

    There is a controversy regarding the safety and efficacy of intracranial stenting. We describe our experience with primary balloon angioplasty without stenting for symptomatic middle cerebral artery (MCA) stenosis. All patients who underwent balloon angioplasty without stenting for MCA stenosis between 1996 and 2010 were retrospectively reviewed. We evaluated technical success rates, degrees of stenosis, and stroke or death within 30 days. Among patients who were followed-up for > 1 year we evaluated latest functional outcomes, stroke recurrence at 1 year, and restenosis. In total 45/47 patients (95.7%) were successfully treated. Average pre- and postprocedure stenosis rates were 79.9% and 39.5%, respectively. Three neurological complications occurred within 30 days: one thromboembolism during the procedure; one lacunar infarction; and one fatal intraparenchymal hemorrhage after the procedure. Stroke or death rate within 30 days was 6.4%. Thirty-three patients were available for follow-up analysis with a mean period of 51.5 months. The combined rate of stroke or death within 30 days and ipsilateral ischemic stroke of the followed-up patients within 1 year beyond 30 days was 9.4%. Restenosis was observed in 26.9% of patients and all remained asymptomatic. In our retrospective series, balloon angioplasty without stenting was a safe, effective modality for symptomatic MCA stenosis. For patients refractory to medical therapy, primary balloon angioplasty may offer a better supplemental treatment option.

  4. Reappraisal of Primary Balloon Angioplasty without Stenting for Patients with Symptomatic Middle Cerebral Artery Stenosis

    PubMed Central

    OKADA, Hideo; TERADA, Tomoaki; TANAKA, Yuko; TOMURA, Nagatsuki; KONO, Kenichi; YOSHIMURA, Ryo; SHINTANI, Aki

    2015-01-01

    There is a controversy regarding the safety and efficacy of intracranial stenting. We describe our experience with primary balloon angioplasty without stenting for symptomatic middle cerebral artery (MCA) stenosis. All patients who underwent balloon angioplasty without stenting for MCA stenosis between 1996 and 2010 were retrospectively reviewed. We evaluated technical success rates, degrees of stenosis, and stroke or death within 30 days. Among patients who were followed-up for > 1 year we evaluated latest functional outcomes, stroke recurrence at 1 year, and restenosis. In total 45/47 patients (95.7%) were successfully treated. Average pre- and postprocedure stenosis rates were 79.9% and 39.5%, respectively. Three neurological complications occurred within 30 days: one thromboembolism during the procedure; one lacunar infarction; and one fatal intraparenchymal hemorrhage after the procedure. Stroke or death rate within 30 days was 6.4%. Thirty-three patients were available for follow-up analysis with a mean period of 51.5 months. The combined rate of stroke or death within 30 days and ipsilateral ischemic stroke of the followed-up patients within 1 year beyond 30 days was 9.4%. Restenosis was observed in 26.9% of patients and all remained asymptomatic. In our retrospective series, balloon angioplasty without stenting was a safe, effective modality for symptomatic MCA stenosis. For patients refractory to medical therapy, primary balloon angioplasty may offer a better supplemental treatment option. PMID:25746307

  5. Balloon angioplasty in acute and chronic coronary artery disease

    SciTech Connect

    Holmes, D.R. Jr.; Vlietstra, R.E. )

    1989-04-14

    Percutaneous transluminal coronary angioplasty has grown exponentially since its introduction. Currently, selection criteria include single-vessel and multivessel disease, stable and unstable angina, and acute infarction. The outcome depends on specific patient and antiographic characteristics. In ideal lesions, success rates should be greater than 90%, with low morbidity and mortality. With more severe and diffuse multivessel disease, success rates are lower and complication rates are higher. In these cases, percutaneous transluminal coronary angioplasty still offers a reasonable option, provided complete revascularization can be achieved or the angina-producing lesion dilated. Numerous issues remain unresolved, including (1) the role of percutaneous transluminal coronary angioplasty vs coronary surgery (currently being tested), (2) restenosis, which occurs in approximately 30% of treated lesions, and (3) organizational adjustments such as training and certification to maintain high standards of care.

  6. Impact of low-power red laser light on restenosis following balloon angioplasty

    NASA Astrophysics Data System (ADS)

    Kipshidze, Nicholas; Horn, Joseph B.; Sahota, Harry; Zulich, Ahmet; Keane, Sean; Baker, John E.; Komorowski, Richard; Nikolaychik, Victor; Keelan, Michael H., Jr.

    1996-12-01

    Despite the widespread application of balloon angioplasty for the treatment of coronary artery disease, restenosis limits the clinical benefits of the procedure. Restenosis is a complex process and may be partly attributed to the inability of the vascular endothelium to regenerate and cover the denuded area at the site of arterial injury. We previously demonstrated that low power red laser light (LPRLL) stimulates endothelial cell proliferation in vitro and contributes to rapid endothelial regeneration following balloon injury in nonatherosclerotic rabbits. We evaluated the long term impact of intravascular LPRLL on restenosis in an atherosclerotic rabbit mode. Rabbit abdominal aortas were subjected to balloon dilatation and balloon dilatation plus laser illumination. Intravascular laser therapy was performed using a 3.0 mm laser-balloon catheter. All rabbits received a single dose of 10 mW for 3 minutes generated from a He-Ne laser. Angiography was performed before and after treatment, and repeated at 60 days prior to harvesting the aortas. Quantitative angiography, morphometric, and histologic analysis revealed that LPRLL treatment prevented balloon-induced adverse changes including intimal proliferation. We conclude that intravascular LPRLL reduces restenosis following balloon angioplasty.

  7. Balloon angioplasty in tibioperoneal interventions for patients with critical limb ischemia.

    PubMed

    Mustapha, J A; Diaz-Sandoval, Larry J

    2014-09-01

    Tibial arterial disease represents the final frontier in the battle against critical limb ischemia (CLI). Isolated infrapopliteal (IP) disease is mainly seen in the elderly (>80 years old), diabetic, and dialysis-dependent patients with CLI. With the development and evolution of catheter-based technology, endovascular therapy (mainly balloon angioplasty) has become the method of choice for revascularization in these patients. The most common challenges are the severely calcified lesion recalcitrant to dilation (as calcium is heterogeneously distributed in the arterial wall) and the long tibial chronic total occlusions. Percutaneous transluminal angioplasty achieves a technically successful result (<30% residual stenosis) in most cases, but it is limited by high restenosis rates. Although several devices have been used in the IP arena (including orbital and directional atherectomy, laser atherectomy, "contact" atherectomy [CROSSER, Bard], and re-entry devices), percutaneous transluminal angioplasty with plain old balloons has been the subject of most studies with several modified iterations, that is, cryoplasty, cutting balloons, focal force balloons, nitinol-"cage"-constrained balloons, tapered balloons, and most recently drug-coated balloons. In this article, we share our current approach to endovascular IP endovascular interventions. We cover the spectrum from pathophysiology, clinical indications, equipment choices, and procedural steps used in our laboratory when treating patients with CLI (which is synonymous with complex anatomy). Regarding what represents the "gold standard" for the treatment of IP disease, a definite answer is currently not available, as multiple studies looking at new generation drug-coated balloons used alone or in combination with different forms of atherectomy are currently under way. We anxiously wait for these results and in the meantime continue to design newer approaches.

  8. Rupture of the Renal Artery After Cutting Balloon Angioplasty in a Young Woman With Fibromuscular Dysplasia

    SciTech Connect

    Oguzkurt, Levent Tercan, Fahri; Gulcan, Oner; Turkoz, Riza

    2005-04-15

    A 24-year-old woman with uncontrollable high blood pressure for 3 months had significant stenosis of the left renal artery caused by fibromuscular dysplasia (FMD). The lesion was resistant to percutaneous transluminal angioplasty at 18 atm with a semicompliant balloon. Angioplasy with a 6 x 10 mm cutting balloon (CB) caused rupture of the artery. Low-pressure balloon inflation decreased but did not stop the leak. An attempt to place a stent-graft (Jostent; Jomed, Rangendingen, Germany) failed, and a bare, 6-mm balloon-expandable stent (Express SD; Boston Scientific, MN) was deployed to seal the leak, which had decreased considerably after long-duration balloon inflation. The bleeding continued, and the patient underwent emergent surgical revascularization of the renal artery with successful placement of a 6-mm polytetrafluoroethylene bypass graft. CBs should be used very carefully in the treatment of renal artery stenosis, particularly in patients with FMD.

  9. Cutting-Balloon Angioplasty Versus Balloon Angioplasty as Treatment for Short Atherosclerotic Lesions in the Superficial Femoral Artery: Randomized Controlled Trial

    SciTech Connect

    Poncyljusz, Wojciech Falkowski, Aleksander; Safranow, Krzysztof Rac, Monika; Zawierucha, Dariusz

    2013-12-15

    Purpose: To evaluate the treatments of a short-segment atherosclerotic stenosis in the superficial femoral arteries with the cutting balloon angioplasty (CBA) versus conventional balloon angioplasty [percutaneous transluminal angioplasty (PTA)] in a randomized controlled trial. Material and Methods: The study group comprised 60 patients (33 men, 27 women; average age 64 years) with a short ({<=}5 cm) focal SFA de novo atherosclerotic stenosis associated with a history of intermittent claudication or rest pain. The primary end point of this study was the rate of binary restenosis in the treated segment 12 months after the intervention. All patients were evenly randomized to either the PTA or CBA treatment arms. Follow-up angiograms and ankle-brachial index (ABI) measurements were performed after 12 months. The evaluation of the restenosis rates and factors influencing its occurrence were calculated by logistic regression analysis. Results: In the intention-to-treat analysis, restenosis rates after 2-month follow-up were 9 of 30 (30 %) in the PTA group and 4 of 30 (13 %) in the CBA group (p = 0.117). In the actual treatment analysis, after exclusion of patients who required nitinol stent placement for a suboptimal result after angioplasty alone (5 patients in the PTA group and none in the CBA group), restenosis rates were 9 of 25 (36 %) and 4 of 30 (13 %), respectively (p = 0.049). In the intention-to-treat analysis there were also significant differences in ABI values between the PTA and CBA groups at 0.77 {+-} 0.11 versus 0.82 {+-} 0.12, respectively (p = 0.039), at 12 months. Conclusion: Based on the presented results of the trial, CBA seems to be a safer and more effective than PTA for treatment of short atherosclerotic lesions in the superior femoral artery.

  10. Laser in infra-popliteal and popliteal stenosis (LIPS): retrospective review of laser-assisted balloon angioplasty versus balloon angioplasty alone for below knee peripheral arterial disease.

    PubMed

    Singh, Tejwant; Kodenchery, Mihas; Artham, Surya; Piyaskulkaew, Chatchawan; Szpunar, Susanna; Parvataneni, Kesav; Ballout, Hussein; Chugtai, Haroon; Stewart, Douglas; Lalonde, Thomas; Yamasaki, Hiroshi

    2014-04-01

    Despite the use of laser technology over the last decade, there are limited data to show its procedural and clinical success in infra-popliteal disease. We hypothesized that laser-assisted balloon angioplasty (LABA) is at least similar or better in procedural and peri-procedural outcomes compared to balloon angioplasty (BA) alone, despite adverse lesion characteristics prior to intervention. Retrospective chart and angiogram review of consecutive critical limb ischemia (CLI) patients who underwent endovascular revascularization in the popliteal or infra-popliteal vessels between 2007 and 2012 with LABA or BA alone. Data from 731 patients revealed that baseline demographics were similar in the LABA (n = 398) and BA group (n = 333) with minor exceptions. More patients in the LABA group had TASC-D lesions (92.5 vs. 66.7 %; P < 0.0001) and chronic total occlusions (CTOs) in both vessel 1 (86.4 vs. 49.5 %; P < 0.0001) and vessel 2 (78.6 vs. 47.8 %; P < 0.0001). Multivariate analysis performed using logistic regression after adjusting for confounding factors showed use of LABA was associated with a 7 times greater likelihood of achieving <50 % residual disease compared to BA alone (OR 7.59, P < 0.0001), and a 5 times greater likelihood of improvement in the infra-popliteal lesion severity score than balloon angioplasty alone (OR 4.77, p < 0.0001). LABA is significantly better at achieving angiographic success and improving lesion severity score in spite of adverse lesion characteristics (more TASC-D lesions and CTOs) compared with BA alone. Our findings suggest that the use of LABA is an endovascular approach that is at least as effective and safe or better compared to BA for the treatment of CLI from complex popliteal and infra-popliteal vascular disease.

  11. Intra-arterial {sup 90}Y brachytherapy: Preliminary dosimetric study using a specially modified angioplasty balloon

    SciTech Connect

    Popowski, Y.; Nouet, P.; Rouzaud, M.

    1995-10-15

    Irradiation has been shown to be effective in preventing restenosis after dilatation in human peripheral arteries. We have developed a dedicated system for coronary intraarterial irradiation using a {sup 90}Y pure beta-emitting source inside a specially modified angioplasty balloon. This paper presents a preliminary dosimetric evaluation of this system. Thermoluminescent dosimetric measurements using the standard balloons filled with contrast medium were plotted semilogarithmically as a function of distance from the balloon surface. The logarithms of the measured doses fit a straight line as a function of depth. The doses at 1 mm and 3 mm are approximately 50 and 10% of the surface dose, respectively. Due to the poor centering of the source in the conventional balloons, the dispersion and standard deviations (SDs) of the measured surface doses increased proportionally to the balloon diameter (SDs are 1.89, 5.52, 5.79, and 6.46 Gy for 2.5, 3, 3.5, and 4 mm balloon diameters, respectively). For the 3.5 mm centering and conventional balloons the respective mean, minimum, and maximum surface doses were 8.41 Gy (min.7.26; max. 9.46) and 7.89 Gy (min. 2.18; max. 16.06) and their standard deviations were 0.66 and 5.79 Gy, respectively. Conventional angioplasty balloons cannot ensure a homogeneous dose delivery to an arterial wall with an intralumenal {sup 90}Y beta source. Preliminary dosimetric results using a modified centering balloon show that it permits improved surface dose distribution (axial and circumferential homogeneity), making it suitable for clinical applications. 9 refs., 5 figs.

  12. On Postoperative Day Balloon Angioplasty for Salvage of Newly-Placed, Flow-Limiting Native Arteriovenous Fistula

    PubMed Central

    Park, Jae Young; Yoo, Chang Hyun

    2015-01-01

    Purpose: To report result and usefulness of immediate postoperative balloon angioplasty of de novo arteriovenous fistula (AVF) with limited flow just after creation. Materials and Methods: From January 1, 2012 to March 31, 2014, 1,270 patients received native AVF creations in a single vascular clinic. In twenty-four patients (1.9% of total AVF creation), immediate postoperative balloon angioplasty was performed because of limited flow on palpation (only pulsation or no thrill) just after AVF creation. Medical records were reviewed retrospectively; technical success (restoration of AVF flow)/clinical success (growing as functional AVF) rate, maturation time, primary patency rate and fistula survival outcome were analyzed during a mean 10.8 months of follow-up. Results: Technical/clinical success rate was 95.8% (23/24 cases); AVF flow was restored after balloon angioplasty, and all the flow-restorated AVFs grew as functional AVFs with mean±standard deviation, 4.5±1.5 weeks of maturation time. In seven (30.4%) patients, a secondary balloon angioplasty was needed to enhance maturation. The overall primary patency after immediate postoperative balloon angioplasty was 69.6% at 1 and 6 months and 59.0% at 12 months. There was 1 complication (operation site hematoma). Conclusion: Immediate postoperative balloon angioplasty for salvage of newly-placed, flow-limiting native AVF is a useful, effective and safe procedure. PMID:26217640

  13. Optical coherence tomography layer thickness characterization of a mock artery during angioplasty balloon deployment

    NASA Astrophysics Data System (ADS)

    Azarnoush, Hamed; Vergnole, Sébastien; Boulet, Benoît; Lamouche, Guy

    2011-03-01

    Optical coherence tomography (OCT) is used to study the deformation of a mock artery in an angioplasty simulation setup. An OCT probe integrated in a balloon catheter provides intraluminal real-time images during balloon inflation. Swept-source OCT is used for imaging. A 4 mm semi-compliant polyurethane balloon is used for experiments. The balloon is inflated inside a custom-built multi-layer artery phantom. The phantom has three layers to mock artery layers, namely, intima, media and adventitia. Semi-automatic segmentation of phantom layers is performed to provide a detailed assessment of the phantom deformation at various inflation pressures. Characterization of luminal diameter and thickness of different layers of the mock artery is provided for various inflation pressures.

  14. Ureteric angioplasty balloon placement to increase localised dosage of BCG for renal pelvis TCC.

    PubMed

    Forde, J C; O'Connor, K M; Fanning, D M; Guiney, M J; Grainger, R

    2012-03-01

    Endoscopic percutaneous resection of a renal pelvis transitional cell carcinoma (TCC) is a viable treatment option in those who would be rendered dialysis dependent following a nephroureterectomy. We report endoscopic percutaneous resection of an upper tract TCC recurrence in a single functioning kidney followed by antegrade renal pelvis BCG instillation with novel placement of inflated angioplasty balloon in the ureter to help localise its effect.

  15. Cutting-Balloon Angioplasty in Transplant Renal Artery Stenosis as First-Line Treatment in the Early Postoperative Period

    SciTech Connect

    Ucar, Adem; Yahyayev, Aghakishi; Bakkaloglu, Huseyin; Agayev, Ayaz; Aydin, Ali Emin; Rozanes, Izzet

    2011-02-15

    Percutaneous transluminal angioplasty has been successfully used for the treatment of transplant renal artery stenosis (RAS). Cutting-balloon angioplasty (CBA) is being used as a second option in pressure-resistant stenosis. It is thought that CBA is less traumatic and therefore restenosis occurs less frequently than in conventional angioplasty. This case report describes the unusual use of a cutting balloon in transplant RAS as a first option in the early postoperative period. Long-term follow-up data are also presented.

  16. Characterization of Pebax angioplasty balloon surfaces with AFM, SEM, TEM, and SAXS.

    PubMed

    Warner, Jacob A; Forsyth, Bruce; Zhou, Fang; Myers, Jason; Frethem, Chris; Haugstad, Greg

    2016-04-01

    In the medical device industry, angioplasty balloons have been widely used in the less invasive treatment of heart disease by expanding and relieving clogged structures in various arterial segments. However, new applications using thin coatings on the balloon surface have been explored to enhance therapeutic value in the delivery of pharmaceuticals (drug-elution) or control thermal energy output (RF ablation). In this study, angioplasty balloon materials comprised of poly(ether-block-amide) (Pebax) were investigated via atomic force microscopy (AFM), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and small-angle X-ray scattering (SAXS) to characterize physical properties at the balloon surface that may affect coating adhesion. The soft segment of this Pebax 1074 material is polyethylene oxide (PEO) and the hard segment is nylon-12. The morphology of the hard segments of this block co-polymer are found via AFM stiffness measurements to be (40 ± 20) nm by (300 ± 150) nm and are oriented parallel to the surface of the balloon. SAXS measurements found the lamellar spacing to be (18.5 ± 0.5) nm, and demonstrate a preferential orientation in agreement with TEM and AFM measurements. Fixation of this balloon in resin, followed by cryo-sectioning is shown to provide a novel manner in which to investigate surface characteristics on the balloon such as material or coating thickness as well as uniformity in comparison to the bulk structure. These outputs were deemed critical to improve overall balloon processing such as molding and surface treatment options for robust designs toward better procedural outcomes targeting new therapeutic areas.

  17. Treatment of in-stent restenosis with excimer laser coronary angioplasty: benefits over scoring balloon angioplasty alone.

    PubMed

    Hirose, Shunsuke; Ashikaga, Takashi; Hatano, Yu; Yoshikawa, Shunji; Sasaoka, Taro; Maejima, Yasuhiro; Isobe, Mitsuaki

    2016-11-01

    Treatment of in-stent restenosis (ISR) is associated with a high incidence of recurrence. This study evaluated the clinical safety and 6-month efficacy of excimer laser coronary angioplasty (ELCA) before scoring balloon dilatation for the treatment of ISR. Twenty-three patients with ISR were included and treatment strategy of ISR was dependent on each operator. Twelve patients among those were treated with ELCA before scoring balloon dilatation (ELCA group) and 11 patients were treated with scoring balloon alone (non-ELCA group). Acute procedural results were evaluated by quantitative coronary angiography (QCA) and frequency domain optical coherence tomography (FD-OCT). Follow-up angiography was performed in all patients and the incidence of recurrent ISR and target lesion revascularization (TLR) was determined at 6 months after initial ISR treatment. Procedural success was achieved in all patients. Baseline clinical and angiographic characteristics were similar between groups. Maximum dilatation pressure of scoring balloon was significantly lower in the ELCA group than in the non-ELCA group (9.0 ± 3.1 vs. 14.9 ± 4.3 atm, p = 0.001). In follow-up angiography, the occurrence of TLR was similar between groups (16.7 vs. 45.5 %, p = 0.09), but the late luminal loss was significantly lower in the ELCA group (0.7 ± 0.6 vs. 1.3 ± 0.7 mm, p = 0.03). ELCA is a safe and feasible technique for the treatment of ISR and associated with a relatively low recurrent restenosis in comparison with scoring balloon dilatation alone.

  18. Percutaneous treatment of thrombosed hemodialysis arteriovenous fistulas: use of thromboaspiration and balloon angioplasty

    PubMed Central

    ÇILDAĞ, BURAK MEHMET; KÖSEOĞLU, KUTSI ÖMER FARUK

    2017-01-01

    Background Endovascular strategies have been used to manage patients with thrombosed vascular access for hemodialysis. We analyzed primary success rate and patency rates of balloon angioplasty following mechanical thrombectomy for the treatment of thrombosed native arteriovenous fistulas. Methods This was a retrospective study of 24 patients with thrombosed native arteriovenous fistulas who were referred for treatment in the intervention unit of the Radiology Department. All patients had been performed percutaneous thrombo-aspiration and balloon angioplasty. Technical and clinical success rates as well as the 6th and 12th months primary and secondary patency of fistulas were evaluated. Results Technical and clinical success was 83%. In the 6 of 20 patients, early re-thrombosis were detected. Patent AVF with primary and secondary patency rates at 6 and 12 months was 55%-40%. The secondary patency rates at 6 and 12 months were 75% and 70%. Conclusion Mechanical thrombectomy with balloon angioplasty is a minimally invasive and effective procedure for the treatment of thrombosed native arteriovenous fistula. Advantages of this technique are minor complication rates, cost effectiveness, high technical success rate. PMID:28246500

  19. Surgical thrombectomy and transluminal balloon angioplasty for failed above-knee femoropopliteal polytetrafluoroethylene bypass grafts.

    PubMed

    Costanza, Michael J; Neschis, David G; Queral, Luis A; Flinn, William R

    2004-03-01

    Endovascular therapy offers an alternative to redo bypass or surgical graft revision for failed above-knee femoropopliteal PTFE bypass grafts. We evaluated the outcome of surgical thrombectomy and balloon angioplasty for the treatment of thrombosed bypass grafts. Thirty selected patients with thrombosed above-knee femoropopliteal PTFE bypass grafts were treated. Under local anesthesia, a surgical thrombectomy followed by bypass graft angiography and balloon angioplasty of perianastomotic stenoses was performed. Stents were used selectively for suboptimal angioplasty results. Patients underwent duplex scanning of the bypass graft postoperatively and at 6-month intervals. Life-table analysis and log-rank (Mantel-Cox) comparisons were performed. Patients were categorized into two groups on the basis of time elapsed from initial bypass graft construction to graft failure. Group 1 included 21 patients with a mean time to graft failure of 10 months (range, 0-20). Surgical thrombectomy was successful in 20 grafts (95%) and 17 patients had a stent placed after angioplasty. Rethrombosis occurred within 30 days in seven grafts (33%) in group 1 and major amputations were performed in six patients (28%). Group 2 included nine patients with a mean time to initial bypass graft failure of 48 months (range, 29-96). All patients in group 2 had a successful surgical thrombectomy and all received a stent. None of the grafts treated in group 2 reoccluded within 30 days of intervention and one patient (11%) went on to require a major amputation. By life-table analysis, the 6- and 12-month patency for group 1 was 15.3% and 5.1%, compared to 58.3% and 38.9% for group 2 (p = 0.027). Surgical thrombectomy along with balloon angioplasty has an unacceptably high rate of failure and limb loss in patients treated for early (<2 years) femoropopliteal PTFE bypass graft thrombosis. Surgical graft revision or redo bypass is recommended to achieve successful revascularization in these patients

  20. Redistribution of von Willebrand factor in porcine carotid arteries after balloon angioplasty.

    PubMed

    Giddings, J C; Banning, A P; Ralis, H; Lewis, M J

    1997-10-01

    von Willebrand factor (VWF) is a well-characterized multimeric glycoprotein present in platelets and plasma and synthesized by vascular endothelial cells and megakaryocytes. Its role in platelet-vessel wall interactions has been studied extensively, but its involvement in intravascular events after balloon angioplasty has not been clarified. VWF antigen is not present in porcine arterial endothelium (except for the pulmonary artery) but is readily detected in porcine venous endothelial cells. We have examined the localization of VWF in porcine vessel walls during neointima formation after bilateral carotid balloon-angioplasty. Endothelium was denuded by balloon injury but regenerated by 7 days and was fully confluent by 42 days. VWF was detected at the site of injury in localized, adherent platelet aggregates at 10 minutes after angioplasty that were not present at later time points. A well-demarcated homogeneous layer of VWF was observed on the luminal surface from 30 minutes to day 7, but there was a progressive shift of positive staining from the lumen to the outer media from days 1 to 7. VWF was also strongly detected at sites proximal and distal to the balloon injury from 30 minutes to day 7, although endothelial disruption was minimal and the monolayer remained substantially intact at these sites. Regrowing endothelial cells appeared to contain granular VWF from days 12 to 21, but this was not readily evident at later time points. The results suggest that balloon injury is associated with deposition and medial absorption of plasma or platelet VWF in this porcine model over a time period that precedes and overlaps vascular smooth muscle proliferation and endothelial recoverage. The findings provide evidence to support the concept of a wider role for VWF in tissue injury responses.

  1. Cutting Balloon-Assisted Angioplasty of an Anastomotic Carotid-Brachial Bypass Graft Stenosis: A Case Report

    SciTech Connect

    Prabhudesai, Vikramaditya; Orme, Richard Fox, Anthony D.

    2004-08-15

    Neointimal hyperplasia leads to anastomotic stenosis in bypass grafts. These stenoses are often resistant to conventional balloon dilatation. We present a case of a carotid-brachial bypass graft stenosis, which was treated by a 5-mm cutting balloon angioplasty with a good angiographic and clinical result.

  2. Cutting Balloon Angioplasty (CBA) Versus Conventional Balloon Angioplasty (PTA) in the Pre-Dilatation of Carotid Artery Stenosis: Our Preliminary Experience

    SciTech Connect

    Cotroneo, Antonio Raffaele Iezzi, Roberto

    2007-11-15

    A retrospective study was carried out to evaluate the efficacy and safety of cutting-balloon angioplasty (CBA) for the predilatation of tight fibrocalcified carotid stenosis before carotid artery stenting (CAS). We also compared the intraprocedural results of CBA with those of conventional percutaneous transluminal angioplasty (PTA) in terms of postdilatation rate. The study population was composed of 32 patients who underwent CAS requiring predilatation before stent implantation. In detail, predilatation was performed by using a conventional balloon (PTA) in 14 patients (group A) and a cutting balloon (CBA) in 18 patients (group B). Intraprocedural and periprocedural mortality, major and minor procedural and neurologic complications, arterial damage, and embolic debris found in the distal filter were recorded. We statistically compared the rate of postdilatation obtained in the two groups. Technical success was obtained in 100% of the cases. No death, major neurologic or periprocedural complications, or arterial damage were recorded in either group. Minor neurologic reactions were recorded in 1 patient from group A (4%) and in 1 patient from group B (3%). Embolic debris was found in the distal filter in 2 patients from group A (8%) and in 3 patients from group B (10%). Postdilatation was necessary in 14 patients from group A (100%) and in 9 patients from group B (50%) (p < 0.05). Although limited to a small number of patients, compared with PTA, CBA seems to be a safe and effective procedure for the predilatation of tight fibrocalcified carotid stenoses before stent placement and may decrease the need for postdilatation in this patient population.

  3. Detection of platelet deposition at the site of peripheral balloon angioplasty using indium-111 platelet scintigraphy

    SciTech Connect

    Pope, C.F.; Ezekowitz, M.D.; Smith, E.O.; Rapoport, S.; Glickman, M.; Sostman, H.D.; Zaret, B.L.

    1985-02-01

    Restenosis after balloon angioplasty may be mediated through platelet deposition at the site of arterial dilatation. The purpose of this study was to determine whether platelet deposition at the site of dilatation could be detected using indium-111 platelet scintigraphy. Fifteen patients, aged 60 +/- 9 years, with iliac or femoral (n . 12), renal artery (n . 2) or distal aortic (n . 1) stenoses were studied. All patients received intravenous heparin at the time of dilatation. Labeled platelets containing 471 +/- 65 muCi indium-111 were injected 0.25 to 4 hours after dilatation and 1 to 24 hours after imaging. In 11 of 12 patients with iliac and femoral dilatations, focal uptake was demonstrated at the angioplasty site. In 4 patients (2 patients with renal, 1 patient with iliofemoral, and 1 with distal aortic stenoses), uptake at the dilatation sites was not detected. This preliminary study indicates that despite intravenous heparin, platelets accumulate at sites of balloon dilatation. Platelet scintigraphy may be useful in predicting sites of future narrowing after angioplasty and may be used to test the efficacy of antiplatelet therapy in retarding restenosis.

  4. Treatment of Chronic Thromboembolic Pulmonary Hypertension: The Role of Medical Therapy and Balloon Pulmonary Angioplasty

    PubMed Central

    Fernandes, Timothy M.; Poch, David S.; Auger, William R.

    2016-01-01

    Chronic thromboembolic pulmonary hypertension (CTEPH) is a potentially curable disease when treated with pulmonary thromboendarterectomy (PTE). However, even at experienced surgical centers, nearly one-third of patients with CTEPH will be deemed inoperable for reasons including distal disease, comorbidities, or out-of-proportion pulmonary hypertension. It is in these patients with inoperable CTEPH that pulmonary hypertension (PH)-targeted medical therapy and balloon pulmonary angioplasty have potential therapeutic value. Previous unblinded cohort trials have assessed PH-targeted medical therapy in various subpopulations of CTEPH patients using epoprostenol, treprostinil, sildenafil, bosentan, and iloprost, each demonstrating measurable pulmonary hemodynamic effects. However, riociguat, a soluble guanylate cyclase stimulator, is the first FDA-approved therapy for inoperable CTEPH to demonstrate both an improvement in functional capabilities (6-minute walk time) as well as significant gains in secondary pulmonary hemodynamic end points in a large placebo-controlled trial. Balloon pulmonary angioplasty is an interventional procedure using telescoping catheters placed in the pulmonary arteries, through which wires and balloons are used to mechanically disrupt chronic clot material and relieve pulmonary vascular obstruction. Contemporary case series from multiple centers worldwide have demonstrated pulmonary hemodynamic improvement with this approach. As a result of these advances, patients with inoperable CTEPH who had few options as recently as 5 years ago now have alternatives with emerging evidence of therapeutic efficacy. PMID:28289495

  5. Morphological differences in coronary arteries following rotational atherectomy versus balloon angioplasty: ultrasound and angioscopic observations

    NASA Astrophysics Data System (ADS)

    Bass, Theodore A.; Gilmore, Paul S.; White, Christopher J.; Chami, Youssef G.; Kircher, Barbara J.; Conetta, Donald A.

    1993-09-01

    Percutaneous transluminal coronary rotational atherectomy (PTCRA) is an exciting new device to recannulate obstructed coronary arteries. This device works as a high speed `drill,' selectively cutting hard atherosclerotic plaque while preferentially sparing the softer, less diseased vascular luminal surface. At speeds as high as 200,000 rpm the plaque is pulverized into small particles easily handled by the circulatory system with no untoward clinical sequela. Balloon angioplasty does not remove atherosclerotic plaque. It dilates the vessel by mechanically stretching, compressing and splitting the plaque and vessel lining. We compare morphological and surface luminal characteristics of vessels post PTCRA to vessels post PTCA.

  6. Successful outcome of emergency coronary artery bypass grafting and retrieval of entrapped stent, angioplasty balloon, and guidewire.

    PubMed

    Karthik, Shishir; Silverton, Paul; Blaxill, Jonathan A; O'Regan, David J

    2005-03-01

    A 42-year-old man presented with worsening of angina after a recent angioplasty and stenting. Repeat angiography revealed further untreated lesions in the left anterior descending coronary artery. The patient underwent re-angioplasty and stenting. After stent deployment, the guidewire and balloon got entrapped in the left anterior descending coronary artery, which was associated with hypotension and ischemic changes of the anterolateral wall on electrocardiogram. The patient was stabilized with the insertion of an intraaortic balloon pump, and he underwent emergency coronary artery bypass grafting and removal of the entrapped equipment. He had an uneventful postoperative recovery.

  7. The STAFF studies of the first 5 minutes of percutaneous coronary angioplasty balloon occlusion in man.

    PubMed

    Warren, Stafford G; Wagner, Galen S

    2014-01-01

    The Staff Studies comprise a database of 228 patients undergoing elective 5 minute coronary artery balloon occlusion angioplasty at a single center in the pre-stent era in whom standard and high-frequency electrocardiographic and nuclear information was obtained immediately before, during and after balloon occlusion. The data were then analyzed by multiple investigators at different international academic centers from different perspectives. Simulating in a clinical setting the first 5 minutes of a heart attack, this database, now in digital format, is the largest database to date documenting standard and high-frequency ECG changes from the onset and for 5 minutes during acute coronary artery occlusion, with resting and occlusion imaging in a subset of these patients. The history, methodology, and legacy of these studies are discussed in this paper.

  8. Dialysis access venous stenosis: treatment with balloon angioplasty 30-second vs. 1-minute inflation times.

    PubMed

    Elramah, Mohsen; Boujelbane, Lamya; Yevzlin, Alexander S; Wakeen, Maureen; Astor, Brad C; Chan, Micah R

    2015-01-01

    Percutaneous balloon angioplasty is the standard of care in the endovascular treatment of dialysis access venous stenosis. The significance of balloon inflation times in the treatment of these stenoses is not well defined. Our objective was to examine the outcomes of 30-second vs. 1-minute balloon inflation times on primary-assisted patency of arteriovenous fistulae and grafts. Using a prospectively collected vascular access database, we identified a total of 75 patients referred for access dysfunction during a 5-year period. These patients received 223 interventions (178 with 30-second inflations and 45 with 1-minute inflations). We compared primary-assisted patency during the subsequent 9 months across groups defined by inflation times. Demographics and baseline characteristics were similar across groups. Immediate technical success and patency in the first 3 months were similar across groups (hazard ratio [HR] = 0.86; 95% confidence interval [CI]: 0.34-2.20). After 3 months, however, a 1-minute inflation time was associated with greater incidence of access failure (adjusted HR [aHR] = 1.74; 95% CI: 1.09-2.79). Other predictors of access failure included age over 60 (aHR = 1.02; 95% CI: 1.01-1.04), central location of the lesion (aHR = 2.49; CI: 1.27-4.89), and three or more prior procedures (aHR 2.48; CI: 1.19-5.16). Our data suggest that shorter balloon inflation times may be associated with improved longer term access patency, although the benefit was not observed until after 3 months. Given the increasing demands of maintaining access patency in the era of the National Kidney Foundation Kidney Disease Outcomes Quality Initiative and Fistula First, the role of angioplasty times requires further study.

  9. Differential glomerular filtration rate in diagnosis of renovascular hypertension and follow-up of balloon angioplasty

    SciTech Connect

    Lamki, L.; Spence, J.D.; MacDonald, A.C.; Roulston, M.

    1986-03-01

    Two hundred nine hypertensive patients with high stimulated plasma renin levels were screened for renovascular hypertension using Tc-99m DTPA renal scintigraphy. Differential glomerular filtration rate (Diff-GFR) was obtained by integrating the area under the background-subtracted renogram of each kidney between 1 and 3 minutes. 50 patients who also had undergone selective renal angiography were divided into four groups according to Diff-GFR contribution by one of the kidneys. If one kidney contributed 45-50% of total GFR, this was regarded as normal. A Diff-GFR of less than 45% was very considered to be very suggestive of renovascular hypertension in the appropriate clinical setting, while a Diff-GFR of less than 20% indicated that the renal artery might not be amenable to successful balloon angioplasty. Diff-GFR following balloon angioplasty closely reflected the early clinical response of the patients--and in some cases progressive Diff-GFR improvement was observed several months later. Diff-GFR as a scintigraphic criterion for renovascular hypertension has a sensitivity of 93%, specificity of 74%, and accuracy of 85%.

  10. [Recanalization of the peripheral arteries by laser thermal balloon angioplasty. 2 years of clinical experience].

    PubMed

    Riambau Alonso, V; Masotti Centol, M; Latorre Vilallonga, J; Viver Manresa, E; Crexells Figueres, C; Oriol Palou, A

    1991-01-01

    Laser angioplasty represents an attractive alternative to overcome the limitations of balloon angioplasty. We describe our results with laser thermal balloon angioplasty (LTBA) in the treatment of atherosclerosis obliterans in the lower limbs after two years clinical follow up. We also analyse the influence of lesion characteristics on immediate results. Thirty seven patients (34 men), whose mean age was 58 +/- 9 years, were included in this study. Occlusive arterial disease (Fontaine stage II-IV), with 39 significant haemodynamic arterial lesions were present in all of them. Ankle/brachial Doppler index was O,51 +/- 0,17. Eighteen lesions were located in the iliac area (13 stenoses 2,3 +/- 1 cm of length and 5 occlusions 4,2 +/- 3 cm) and 21 lesions in femoro-popliteal area (5 stenoses 2,6 +/- 2 cm and 16 occlusions 5,7 +/- 3 cm). A percutaneous procedure was used in 38 cases and only in one case a femoral dissection was necessary. The laser source was argon in 26 cases and Nd-YAG in 13. The overall immediate angiographic and clinical success was 85% (89% in iliac lesions and 81% in femoropopliteal lesions; 100% in stenoses and 70% in occlusions). The presence of occlusion (p less than 0,01) and/or calcium (p less than O,05) influenced negatively the immediate results. No major complications were observed. Seven (17%) minor complications occurred, but no emergency surgery was necessary. The ankle/brachial Doppler index after treatment was 0,82 +/- 0,21. Cumulative clinical patency was 91% for successfully treated patients after two years follow up. We conclude that LTBA represents an effective and less aggressive way to treat atherosclerosis obliterans.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Application of conjugated heparin-albumin microparticles with laser-balloon angioplasty: a potential method for reducing adverse biologic reactivity after angioplasty

    NASA Astrophysics Data System (ADS)

    Kundu, Sourav K.; McMath, Linda P.; Zaidan, Jonathan T.; Spears, J. Richard

    1991-05-01

    Laser-balloon angioplasty (LBA) may potentially be used for local application of pharmacologically active agents which will reduce thrombogenic and proliferative responses after the angioplasty. In this study, the feasibility of applying covalently conjugated heparin- albumin microparticles onto arterial luminal surface was demonstrated. The covalent linkages were formed by reaction with 1-ethyl-3-dimethyl-aminopropyl-carbodiimide (EDC), and the resultant conjugates were used for preparation of microparticles by employing standard emulsification and heat-crosslinking techniques. The heparin release rate from the microparticles was found to be dependent upon the degree of crosslinking. When a thin coagulum of a suspension of microparticles was formed with heat on a glass surface, the treated surface demonstrated resistance to clot formation in contact with non-anticoagulated blood. A suspension of the microparticles applied during laser-balloon angioplasty onto the luminal surface of dog carotid and femoral arteries showed persistence for up to one week without thrombus formation or occlusion of the vessel. Since the rate of biodegradation is primarily dictated by the extent of crosslinking, an optimal degree of thermal denaturation will permit longer persistence of the carrier while allowing adequate release of the entrapped pharmacologic agent. A variety of antithrombotic and antiinflammatory agents are being considered as candidate bioprotective materials for local application after angioplasty.

  12. Critical appraisal of paclitaxel balloon angioplasty for femoral-popliteal arterial disease.

    PubMed

    Herten, Monika; Torsello, Giovanni B; Schönefeld, Eva; Stahlhoff, Stefan

    2016-01-01

    Peripheral arterial disease, particularly critical limb ischemia, is an area with urgent need for optimized therapies because, to date, vascular interventions often have limited life spans. In spite of initial encouraging technical success after femoropopliteal percutaneous transluminal angioplasty or stenting, postprocedural restenosis remains the major problem. The challenging idea behind the drug-coated balloon (DCB) concept is the biological modification of the injury response after balloon dilatation. Antiproliferative drugs administered via DCBs or drug-eluting stents are able to suppress neointimal hyperplasia, the main cause of restenosis. This article reviews the results of DCB treatments of femoropopliteal and infrapopliteal lesions in comparison to standard angioplasty with uncoated balloons. A systematic literature search was performed in 1) medical journals (ie, MEDLINE), 2) international registers for clinical studies (ie, www.clinicaltrials.gov), and 3) abstracts of scientific sessions. Several controlled randomized trials with follow-up periods of up to 5 years demonstrated the efficacy of paclitaxel -DCB technology. However, calcified lesions seem to affect the efficacy of DCB. Combinations of preconditioning methods with DCBs showed promising results. Although the mechanical abrasion of calcium via atherectomy or laser ablation showed favorable periprocedural results, the long-term impact on restenosis and clinical outcome has to be demonstrated. Major advantages of the DCBs are the rapid delivery of drug at uniform concentrations with a single dose, their efficacy in areas wherein stents have been contraindicated until now (ie, bifurcation, ostial lesions), and in leaving no stent scaffold behind. Reinterventions are easier to perform because DCBs leave no metal behind. Various combinations of DCBs with other treatment modalities may prove to be viable options in future. The follow-up results of clinical studies will evaluate the long-term impact

  13. Critical appraisal of paclitaxel balloon angioplasty for femoral–popliteal arterial disease

    PubMed Central

    Herten, Monika; Torsello, Giovanni B; Schönefeld, Eva; Stahlhoff, Stefan

    2016-01-01

    Peripheral arterial disease, particularly critical limb ischemia, is an area with urgent need for optimized therapies because, to date, vascular interventions often have limited life spans. In spite of initial encouraging technical success after femoropopliteal percutaneous transluminal angioplasty or stenting, postprocedural restenosis remains the major problem. The challenging idea behind the drug-coated balloon (DCB) concept is the biological modification of the injury response after balloon dilatation. Antiproliferative drugs administered via DCBs or drug-eluting stents are able to suppress neointimal hyperplasia, the main cause of restenosis. This article reviews the results of DCB treatments of femoropopliteal and infrapopliteal lesions in comparison to standard angioplasty with uncoated balloons. A systematic literature search was performed in 1) medical journals (ie, MEDLINE), 2) international registers for clinical studies (ie, www.clinicaltrials.gov), and 3) abstracts of scientific sessions. Several controlled randomized trials with follow-up periods of up to 5 years demonstrated the efficacy of paclitaxel –DCB technology. However, calcified lesions seem to affect the efficacy of DCB. Combinations of preconditioning methods with DCBs showed promising results. Although the mechanical abrasion of calcium via atherectomy or laser ablation showed favorable periprocedural results, the long-term impact on restenosis and clinical outcome has to be demonstrated. Major advantages of the DCBs are the rapid delivery of drug at uniform concentrations with a single dose, their efficacy in areas wherein stents have been contraindicated until now (ie, bifurcation, ostial lesions), and in leaving no stent scaffold behind. Reinterventions are easier to perform because DCBs leave no metal behind. Various combinations of DCBs with other treatment modalities may prove to be viable options in future. The follow-up results of clinical studies will evaluate the long

  14. The Falconª Eccentric Coronary Balloon Angioplasty Catheter: A Randomized Safety and Efficacy Study.

    PubMed

    Qureshi; Peels; den Heijer P; van Boven AJ; Tio; de Kam PJ; Crijns

    1997-10-01

    Percutaneous coronary angioplasty (PTCA) is usually performed using concentric shaped balloon catheters with the guidewire passing through the center of the shaft. The Falconª balloon catheter features a guide wire lumen on the outside of the balloon so that an eccentric balloon catheter profile is obtained concentrating the dilating force on the wire supported side, allowing lower inflation pressures and potentially causing less vessel injury. The aim of this study was to evaluate the safety and efficacy of this new balloon catheter in patients with stable and unstable angina. In 95 prospectively randomized patients, 57 lesions were dilated with a concentric balloon and 51 with the eccentric balloon. Technical success in the two groups was similar (73.3% vs. 74.5% control vs. Falcon respectively). Procedural success was 96.5% vs. 96.1% in the control and Falcon groups respectively. The mean increase in minimum luminal diameter (MLD) was 1.01 +/- 0.41 mm in the control vs 0.85 +/- 0.45 mm in Falcon (p = 0.053). There was an increase in type A dissections in the Falcon group 18 (36.75%) vs. 10 (19.23%) in the control group (p = 0.07) with no difference in stent implantation, myocardial infarction, CABG or death between the two groups. All patients with a technically successful PTCA were followed up. Seventeen (43.6%) in the control and 11 (32.4%) in the Falcon had repeat coronary angiography (p = 0.38), 12 (30.8%) vs. 7 (20.6%) had repeat PTCA (p = 0.37) and time to PTCA was 116 +/- 70 days vs. 154 +/- 103 days respectively (p = 0.36). The Falcon performed technically as well as the concentric balloons. Despite a smaller MLD and increase in Type A dissections there was no associated increase in complications or reintervention for restenosis. Further investigation is required to evaluate the role of this mechanism of dilatation in restenosis.

  15. Concurrent Angioplasty Balloon Placement for Stent Delivery through Jugular Venous Bulb for Treating Cerebral Venous Sinus Stenosis. Technical Report

    PubMed Central

    Qureshi, Adnan I.; Khan, Asif A.; Capistrant, Rachel; Qureshi, Mushtaq H.; Xie, Kevin; Suri, M. Fareed K.

    2016-01-01

    OBJECTIVE To report upon technique of concurrent placement of angioplasty balloon at the internal jugular vein and sigmoid venous sinus junction to facilitate stent delivery in two patients in whom stent delivery past the jugular bulb was not possible. CLINICAL PRESENTATION A 21-year-old woman and a 41-year-old woman with worsening headaches, visual obscuration or diplopia were treated for pseudotumor cerebri associated with transverse venous stenosis. Both patients had undergone primary angioplasty, which resulted in improvement in clinical symptoms followed by the recurrence of symptoms with restenosis at the site of angioplasty. INTERVENTION After multiple attempts at stent delivery through jugular venous bulb were unsuccessful, a second guide catheter was placed in the ipsilateral internal jugular vein through contralateral femoral venous approach. A 6 mm × 20 mm (left) or 5 × 15 mm (right) angioplasty balloon was placed across the internal jugular vein and sigmoid sinus junction and partially inflated until the inflation and relative straightening of the junction was observed. In both patients, the internal jugular vein and sigmoid sinus junction was successfully traversed by the stent delivery system in a parallel alignment to inflated balloon. Balloon mounted stent was deployed at the site of restenosis with near complete resolution of lumen narrowing delivery and improvement in clinical symptoms. CONCLUSION We report a technique for realignment and diameter change with concurrent placement and partial inflation of angioplasty balloon at the jugular venous bulb to facilitate stent delivery into the sigmoid and transverse venous sinuses in circumstances where multiple attempts at stent delivery are unsuccessful. PMID:27829971

  16. Angioplasty and stent placement - peripheral arteries - discharge

    MedlinePlus

    Percutaneous transluminal angioplasty - peripheral artery - discharge; PTA - peripheral artery - discharge; Angioplasty - peripheral artery - discharge; Balloon angioplasty - peripheral artery- discharge; PAD - PTA discharge; PVD - PTA discharge

  17. Comparison of Angiography and Intravascular Ultrasound Before and After Balloon Angioplasty of the Femoropopliteal Artery

    SciTech Connect

    Lankeren, Winnifred van; Gussenhoven, Elma J.; Pieterman, Herman; Sambeek, Marc R.H.M. van; Lugt, Aad van der

    1998-09-15

    Purpose: To compare angiographic and intravascular ultrasound (IVUS) data before and after balloon angioplasty (PTA) of the femoropopliteal artery. Methods: Qualitative and quantitative analyses were performed on corresponding angiographic and IVUS levels obtained from 135 patients. Results: IVUS detected more lesions, calcified lesions, and vascular damage than angiography. Sensitivity of angiography was good for the presence of a lesion (84%), moderate for eccentric lesions (53%) and for vascular damage (52%), and poor for calcified lesions (30%). The increase in angiographic diameter stenosis was associated with a decrease in lumen area and increase in percentage area stenosis on IVUS. Conclusions: Angiography is less sensitive than IVUS for detecting lesion eccentricity, calcified lesions, and vascular damage. Presence of a lesion and amount of plaque were underestimated angiographically. Only before PTA was good agreement found between angiographic diameter stenosis and lumen size on IVUS.

  18. A novel arterial constitutive model in a commercial finite element package: Application to balloon angioplasty.

    PubMed

    Zhao, Xuefeng; Liu, Yi; Zhang, Wei; Wang, Chong; Kassab, Ghassan S

    2011-10-07

    Recently, a novel linearized constitutive model with a new strain measure that absorbs the material nonlinearity was validated for arteries. In this study, the linearized arterial stress-strain relationship is implemented into a finite element method package, ANSYS, via the user subroutine USERMAT. The reference configuration is chosen to be the closed cylindrical tube (no-load state) rather than the open sector (zero-stress state). The residual strain is taken into account by analytic calculation and the incompressibility condition is enforced with Lagrange penalty method. Axisymmetric finite element analyses are conducted to demonstrate potential applications of this approach in a complex boundary value problem where angioplasty balloon interacts with the vessel wall. The model predictions of transmural circumferential and compressive radial stress distributions were also validated against an exponential-type Fung model, and the mean error was found to be within 6%.

  19. Site-targeted acoustic contrast agent detects molecular expression of tissue factor after balloon angioplasty

    NASA Astrophysics Data System (ADS)

    Hall, Christopher S.; Abendschein, Dana R.; Scherrer, David E.; Scott, Michael J.; Marsh, Jon N.; Wickline, Samuel A.; Lanza, Gregory M.

    2000-04-01

    Complex molecular signaling heralds the early stages of pathologies such as angiogenesis, inflammation, and cellular responses to mechanically damaged coronary arteries after balloon angioplasty. In previous studies, we have demonstrated acoustic enhancement of blood clot morphology with the use of a nongaseous, ligand-targeted acoustic nanoparticle emulsion delivered to areas of thrombosis both in vitro and in vivo. In this paper, we characterize the early expression of tissue factor which contributes to subsequent arterial restenosis. Tissue factor is a 42kd glycoprotein responsible for blood coagulation but also plays a well-described role in cancer metastasis, angiogenesis, and vascular restenosis. This study was designed to determine whether the targeted contrast agent could localize tissue factor expressed within the wall of balloon-injured arteries. Both carotid arteries of five pigs (20 kg) were injured using an 8 X 20 mm angioplasty balloon. The carotids were treated in situ with a perfluorocarbon nanoparticle emulsion covalently complexed to either specific anti-tissue factor polyclonal F(ab) fragments (treatment) or non-specific IgG F(ab) fragments (control). Intravascular ultrasound (30 MHz) images of the arteries were obtained before and after exposure to the emulsions. Tissue- factor targeted ultrasonic contrast agent acoustically enhanced the subintima and media at the site of balloon- induced injury compared with control contrast arteries (p less than 0.05). Immunohistochemical staining confirmed the presence of increased tissue factor at the sites of acoustic enhancement. Binding of the targeted agents was demonstrated in vitro by scanning electron microscope images of cultured smooth muscle cells that constitutively express tissue factor. This study demonstrates the concept of molecular imaging and localization of carotid arteries' tissue factor in vivo using a new, nanoparticulate emulsion. Enhancement of the visualization of the molecular

  20. Efficacy of Local Molsidomine Delivery from a Hydrogel-Coated Angioplasty Balloon Catheter in the Atherosclerotic Porcine Model

    SciTech Connect

    Rolland, Pierre H.; Mekkaoui, Choukri; Palassi, Maria; Friggi, Alain; Moulin, Guy; Piquet, Philippe; Bartoli, Jean-Michel

    2003-02-15

    Purpose: To evaluate the therapeutic effects of local molsidomine delivery via a hydrogel-coated angioplasty balloon catheter during overstretch angioplasty in atheroscleroticswine iliac vessels. Molsidomine is retained in the arterial wall after local delivery for more than 72 hr and is slowly metabolized intolinsidomine, releasing nitric oxide (NO). Methods: A hydrogel-coated angioplasty balloon catheter was used to both deliver drug locally (150 mg molsidomine or placebo in the contralateral vessel) and dilate iliac vessels in nine Pietrin pigs that had been on an atherogenic diet for 5 months. Animals were killed at 3 hr(n = 2), 24 hr (n = 3) and 3 months(n = 3) after treatment. Iliac arteries were examined for wall pulsatility, histomorphometry, cell proliferation and platelet aggregation. Results: No significant therapeutic effects were detected 3 hr after treatment. At 24 hr, wall pulsatility,thrombo resistance and vascular cell homeostasis were significantly restored in the molsidomine-treated versus placebo group. At 3 months,molsidomine inhibited restenotic lesion development, except in scarred areas of histologically detectable adventitial/medial dissection. Conclusion: Local delivery of concentrated molsidomine from a hydrogel-coated angioplasty balloon catheter resulted in early NO-dependent vasodilation/stress normalization and antithrombotic and antiproliferative effects. In the medium term, molsidomine inhibited restenosis in the absence of vessel dissection.

  1. Primary Cutting Balloon Angioplasty for Treatment of Venous Stenoses in Native Hemodialysis Fistulas: Long-Term Results from Three Centers

    SciTech Connect

    Bhat, Rajesh McBride, Kieran; Chakraverty, Sam; Vikram, Raghunandan; Severn, Alison

    2007-11-15

    Aim. To evaluate the technical success and patency rates following primary cutting balloon angioplasty for venous stenoses in native dialysis fistulas. Methods. Forty-one patients (26 men, 15 women; age range 26-82 years, average age 59 years) underwent 50 (repeat procedures in 9 patients) primary cutting balloon (PCB) angioplasty procedures in three institutions by three primary operators. The indication was primary stenosis in 21 patients, recurrent lesions in 15, and immature fistulas in 5. A PCB was used alone in 17 cases, but was followed by a larger standard balloon in 33 cases. Follow-up included ultrasound, flow analysis and urea reduction ratio, and ranged from 2 to 30 months (mean 14 months). Results. The technical success rate was 98%. All procedures were relatively painless. Two PCBs burst and 4 leaked, but without causing any morbidity. Nineteen fistulas were still working at last follow-up. Primary patency rates at 6, 12, and 24 months using Kaplan-Meier analysis were 88%, 73%, and 34%, respectively, and the primary assisted patencies were 90%, 75%, and 50%, respectively. Conclusion. PCB angioplasty has high technical success and low complication rates. The long-term patency rates are favorable for PCB angioplasty and compare favorably with other series.

  2. Cutting Balloon Angioplasty of Bilateral Renal Artery Stenosis Due to Takayasu Arteritis in a 5-Year-Old Child with Midterm Follow-Up

    SciTech Connect

    Gumus, Burcak Cevik, Halime; Vuran, Can; Omay, Oguz; Kocyigit, Ozgen Ilgaz; Turkoz, Riza

    2010-04-15

    The aim of this report is to demonstrate the successful endovascular treatment of bilateral renal artery stenosis due to Takayasu arteritis by cutting balloon angioplasty in a 5-year-old child with mid-term follow-up.

  3. Association Between Disruption of Fibrin Sheaths Using Percutaneous Transluminal Angioplasty Balloons and Late Onset of Central Venous Stenosis

    SciTech Connect

    Ni, Nina Mojibian, Hamid; Pollak, Jeffrey; Tal, Michael

    2011-02-15

    To compare the rates of central venous stenosis in patients undergoing hemodialysis who underwent disruption of fibrin sheath with percutaneous transluminal angioplasty balloons and those who underwent over-the-wire catheter exchange. This study is a retrospective review of 209 percutaneous transluminal angioplasty balloon disruption and 1304 over-the-wire catheter exchange procedures performed in 753 patients. Approval from the Human Investigations Committee was obtained for this study. Up to 10-year follow-up was performed. A {chi}{sup 2} test was used to compare the rates of central venous stenosis after balloon disruption versus catheter exchange. A t-test was used to compare time to central venous stenosis development. Of the 753 patients in the study, 127 patients underwent balloon disruption of fibrin sheath and 626 had catheter exchange. Within the balloon disruption group, 18 (14.2%) of 127 patients subsequently developed central venous stenosis, compared with 44 (7.0%) of 626 in the catheter exchange group (P < 0.01, {chi}{sup 2} test). Time to central venous stenosis development was approximately 3 years in both groups and not significantly different (1371 and 1010 days, P = 0.20). A total of 25.2% of patients in the balloon disruption group had four or more subsequent catheter exchanges, versus 12.6% in the catheter exchange group (P < 0.01, {chi}{sup 2} test). In conclusions, there is a possible association between percutaneous transluminal angioplasty balloon disruption of fibrin sheath and late-onset central venous stenosis. Because venography was not routinely performed in catheter exchange patients, future randomized studies are necessary to confirm these findings.

  4. Cryoplasty Versus Conventional Balloon Angioplasty of the Femoropopliteal Artery in Diabetic Patients: Long-Term Results from a Prospective Randomized Single-Center Controlled Trial

    SciTech Connect

    Spiliopoulos, Stavros Katsanos, Konstantinos; Karnabatidis, Dimitris; Diamantopoulos, Athanasios; Kagadis, George C.; Christeas, Nikolaos; Siablis, Dimitris

    2010-10-15

    The purpose of this study was to investigate the immediate and long-term results of cryoplasty versus conventional balloon angioplasty in the femoropopliteal artery of diabetic patients. Fifty diabetic patients (41 men, mean age 68 years) were randomized to cryoplasty (group CRYO; 24 patients with 31 lesions) or conventional balloon angioplasty (group COBA; 26 patients with 34 lesions) of the femoropopliteal artery. Technical success was defined as <30% residual stenosis without any adjunctive stenting. Primary end points included technical success, primary patency, binary in-lesion restenosis (>50%), and freedom from target lesion recanalization. Cox proportional hazards regression analysis was performed to adjust for confounding factors of heterogeneity. In total, 61.3% (19 of 31) in group CRYO and 52.9% (18 of 34) in group COBA were de novo lesions. More than 70% of the lesions were Transatlantic Inter-Society Consensus (TASC) B and C in both groups, and 41.4% of the patients in group CRYO and 38.7% in group COBA suffered from critical limb ischemia. Immediate technical success rate was 58.0% in group CRYO versus 64.0% in group COBA (p = 0.29). According to 3-year Kaplan-Meier estimates, there were no significant differences with regard to patient survival (86.8% in group CRYO vs. 87.0% in group COBA, p = 0.54) and limb salvage (95.8 vs. 92.1% in groups CRYO and COBA, respectively, p = 0.60). There was a nonsignificant trend of increased binary restenosis in group CRYO (hazard ratio [HR] 1.3; 95% CI 0.6-2.6, p = 0.45). Primary patency was significantly lower in group CRYO compared with group COBA (HR 2.2; 95% CI 1.1-4.3, p = 0.02). Significantly more repeat intervention events because of recurrent symptoms were required in group CRYO (HR 2.5; 95% CI 1.2-5.3, p = 0.01). Cryoplasty was associated with lower primary patency and more clinically driven repeat procedures after long-term follow-up compared with conventional balloon angioplasty.

  5. Low-dose psoralen and UVA (PUVA) therapy-enhanced arterial shrinkage after balloon angioplasty in rabbits

    NASA Astrophysics Data System (ADS)

    Perree, Jop; van Leeuwen, Ton G. J. M.; Velema, Evelyn; Borst, Cornelius

    1998-07-01

    Restenosis after balloon angioplasty is caused by both intimal hyperplasia and arterial shrinkage (constrictive remodeling). Previous studies have indicated the inhibitory effect of photodynamic therapy on intimal hyperplasia development after angioplasty. The potential of a photoactivation regime (Psoralen + UVA irradiation: PUVA), which does not cause unwanted systemic side effects, for the prevention of both intimal hyperplasia formation and constrictive remodeling following balloon dilation was explored in the present study. In the rabbit iliac artery, balloon dilation followed by PUVA- therapy at a radiant exposure of 1 J/cm2 was performed (n equals 10). Control balloon dilation was performed in the contralateral arteries (n equals 10). After 4 weeks of survival, angiographic lumen renarrowing was determined in terms of intimal hyperplasia and constrictive remodeling. Late loss, but not intimal hyperplasia, was significantly larger in the PUVA group as compared to the control group (p less than 0.05). This difference in angiographic lumen loss can only be attributed to the difference in constrictive remodeling (arterial shrinkage). Thus, PUVA-therapy did not prevent intimal hyperplasia following balloon dilation. PUVA-therapy even enhanced luminal narrowing by augmented constrictive arterial remodeling.

  6. Deep sea water prevents balloon angioplasty-induced hyperplasia through MMP-2: an in vitro and in vivo study.

    PubMed

    Li, Pei-Chuan; Pan, Chun-Hsu; Sheu, Ming-Jyh; Wu, Chin-Ching; Ma, Wei-Fen; Wu, Chieh-Hsi

    2014-01-01

    Major facts about the development of restenosis include vascular smooth muscle cells (VSMCs) proliferation and migration. A previous study showed that in vitro treatment with magnesium chloride has the potential to affect the proliferation and migration of VSMCs. Magnesium is the major element in deep sea water (DSW) and is a biologically active mineral. It is unclear whether DSW intake can prevent abnormal proliferation and migration of VSMCs as well as balloon angioplasty-induced neointimal hyperplasia. Thus, we attempted to evaluate the anti-restenotic effects of DSW and its possible molecular mechanisms. Several concentrations of DSW, based on the dietary recommendations (RDA) for magnesium, were applied to a model of balloon angioplasty in SD rats. The results showed that DSW intake markedly increased magnesium content within the vascular wall and reduced the development of neointimal hyperplasia. The immunohistochemical analysis also showed that the expression of proteins associated with cell proliferation and migration were decreased in the balloon angioplasty groups with DSW supplement. Furthermore, in vitro treatment with DSW has a dose-dependent inhibitory effect on serum-stimulated proliferation and migration of VSMCs, whose effects might be mediated by modulation of mitogen-activated protein kinase (MAPK) signaling and of the activity of matrix metalloproteinase-2 (MMP-2). Our study suggested that DSW intake can help prevent neointimal hyperplasia (or restenosis), whose effects may be partially regulated by magnesium and other minerals.

  7. Balloon Angioplasty – The Legacy of Andreas Grüntzig, M.D. (1939–1985)

    PubMed Central

    Barton, Matthias; Grüntzig, Johannes; Husmann, Marc; Rösch, Josef

    2014-01-01

    In 1974, at the Medical Policlinic of the University of Zürich, German-born physician-scientist Andreas Grüntzig (1939–1985) for the first time applied a balloon-tipped catheter to re-open a severely stenosed femoral artery, a procedure, which he initially called “percutaneous transluminal dilatation”. Balloon angioplasty as a therapy of atherosclerotic vascular disease, for which Grüntzig and Charles T. Dotter (1920–1985) received a nomination for the Nobel Prize in Physiology or Medicine in 1978, became one of the most successful examples of translational medicine in the twentieth century. Known today as percutaneous transluminal angioplasty (PTA) in peripheral arteries or percutaneous transluminal coronary angioplasty (PTCA) or percutaneous coronary intervention (PCI) in coronary arteries, balloon angioplasty has become the method of choice to treat patients with acute myocardial infarction or occluded leg arteries. On the occasion of the 40th anniversary of balloon angioplasty, we summarize Grüntzig’s life and career in Germany, Switzerland, and the United States and also review the developments in vascular medicine from the 1890s to the 1980s, including Dotter’s first accidental angioplasty in 1963. The work of pioneers of catheterization, including Pedro L. Fariñas in Cuba, André F. Cournand in France, Werner Forssmann, Werner Porstmann and Eberhard Zeitler in Germany, António Egas Moniz and Reynaldo dos Santos in Portugal, Sven-Ivar Seldinger in Sweden, and Barney Brooks, Thomas J. Fogarty, Melvin P. Judkins, Richard K. Myler, Dickinson W. Richards, and F. Mason Sones in the United States, is discussed. We also present quotes by Grüntzig and excerpts from his unfinished autobiography, statements of Grüntzig’s former colleagues and contemporary witnesses, and have included hitherto unpublished historic photographs and links to archive recordings and historic materials. This year, on June 25, 2014, Andreas Grüntzig would have celebrated

  8. Randomized Trial of the SMART Stent versus Balloon Angioplasty in Long Superficial Femoral Artery Lesions: The SUPER Study

    SciTech Connect

    Chalmers, Nicholas; Walker, Paul T.; Belli, Anna-Maria; Thorpe, Anthony P.; Sidhu, Paul S.; Robinson, Graham; Ransbeeck, Mariella van

    2013-04-15

    To determine whether primary stenting reduces the rate of restenosis compared with balloon angioplasty alone in the endovascular treatment of long superficial femoral artery lesions; and to assess the effect of treatment on quality of life. A total of 150 patients with superior femoral artery occlusion or severe stenosis of 5-22 cm length from 17 UK centers were randomized to either primary stenting with the SMART stent or balloon angioplasty (i.e., percutaneous transluminal angioplasty, PTA). Bailout stent placement was permitted in case of inadequate result from PTA. The primary end point was restenosis measured by duplex ultrasound at 1 year. Quality-of-life assessments were performed by the EuroQol (EQ)-5D questionnaire. Mean lesion length was 123.0 mm in the stent group and 116.8 mm in the PTA group. A total of 140 (93.3 %) of 150 had total occlusions. At 12 months' follow-up, restenosis measured by Duplex ultrasound was not significantly different between the stent and PTA groups by intention-to-treat or as-treated analyses: 47.2 versus 43.5 % (p = 0.84) and 40.8 versus 46.7 % (p = 0.68), respectively. There were fewer target lesion revascularizations in patients randomized to stenting, but this did not reach statistical significance (12.5 vs. 20.8 %, p = 0.26). There was no difference in the rate of amputation. Patients in both groups reported improved quality of life. Primary stenting of long lesions in predominantly occluded superficial femoral arteries does not reduce the rate of binary restenosis compared with balloon angioplasty and bailout stenting. Both treatment strategies conferred a meaningful and sustained improvement to the quality of life of patients with severe superficial femoral artery disease.

  9. Finite Element Modeling of Balloon Angioplasty by Considering Overstretch of Remnant Non-diseased Tissues in Lesions

    NASA Astrophysics Data System (ADS)

    Gasser, T. Christian; Holzapfel, Gerhard A.

    2007-06-01

    The paper deals with the modeling of balloon angioplasty by considering the balloon-induced overstretch of remnant non-diseased tissues in atherosclerotic arteries. A stenotic artery is modeled as a heterogenous structure composed of adventitia, media and a model plaque, and residual stresses are considered. The constitutive models are able to capture the anisotropic elastic tissue response in addition to the inelastic phenomena associated with tissue stretches beyond the physiological domain. The inelastic model describes the experimentally-observed changes of the wall during balloon inflation, i.e. non-recoverable deformation, and tissue weakening. The contact of the artery with a balloon catheter is simulated by a point-to-surface strategy. The states of deformations and stresses within the artery before, during and after balloon inflation are computed, compared and discussed. The 3D stress states at physiological loading conditions before and after balloon inflation differ significantly, and even compressive normal stresses may occur in the media after dilation.

  10. Cool excimer laser-assisted angioplasty (CELA) and tibial balloon angioplasty (TBA) in management of infragenicular arterial occlusion in critical lower limb ischemia (CLI).

    PubMed

    Sultan, Sherif; Tawfick, Wael; Hynes, Niamh

    2013-04-01

    We aim to compare cool excimer laser-assisted angioplasty (CELA) versus tibial balloon angioplasty (TBA) in patients with critical limb ischemia (CLI) with tibial artery occlusive disease. The primary end point is sustained clinical improvement (SCI) and amputation-free survival (AFS). The secondary end points are binary restenosis, target extremity revascularization (TER), and cost-effectiveness. From June 2005 to October 2010, 1506 patients were referred with peripheral vascular disease and 572 with CLI. A total of 80 patients underwent 89 endovascular revascularizations (EVRs) for tibial occlusions, 47 using TBA and 42 using CELA. All patients were Rutherford category 4 to 6. Three-year SCI was enhanced with CELA (81%) compared to TBA (63.8%; P = .013). Three-year AFS significantly improved with CELA (95.2%) versus TBA (89.4%; P = .0165). Three-year freedom from TER was significantly improved with CELA (92.9%) versus 78.7% TBA (P = .026). Three-year freedom from MACE was comparable in both the groups (P = .455). Patients with CELA had significantly improved quality time without symptoms of disease or toxicity of treatment (Q-TWiST) at 3 years (10.5 months; P = .048) with incremental cost of €2073.19 per quality-adjusted life year gained. Tibial EVR provides exceptional outcome in CLI. The CELA has superior SCI, AFS, and freedom from TER, with improved Q-TWiST and cost-effectiveness.

  11. Predilation technique with balloon angioplasty to facilitate percutaneous groin access of large size sheath through scar tissue.

    PubMed

    Pecoraro, Felice; Krishnaswamy, Mayur; Steuer, Johnny; Puippe, Gilbert; Mangialardi, Nicola; Pfammatter, Thomas; Rancic, Zoran; Veith, Frank J; Cayne, Neal S; Lachat, Mario

    2017-01-01

    Purpose Percutaneous remote access for endovascular aortic repair is an advantageous alternative to open access. Previous surgery in the femoral region and the presence of synthetic vascular grafts in the femoral/iliac arteries represent major limitations to percutaneous remote access. The aim of this study was to evaluate an original technique used for enabling percutaneous remote access for thoracic or abdominal endovascular aortic repair in patients with scar tissue and/or a vascular graft in the groin. Methods Twenty-five consecutive patients with a thoracic (11/25; 44%) or an aortic aneurysm (14/25; 66%) and with a synthetic vascular graft in the groin (16/25; 64%) or a redo groin access (9/25; 36%) were managed through the percutaneous remote access. In all patients, a percutaneous transluminal angioplasty balloon was used to predilate the scar tissue and the femoral artery or the synthetic vascular graft after preclosing (ProGlide®; Abbott Vascular, Santa Clara, CA, USA). In 10 patients, requiring a 20 Fr sheath, a 6 mm percutaneous transluminal angioplasty balloon was used; and in the remaining 15, requiring a 24 Fr sheath, an 8 mm percutaneous transluminal angioplasty balloon. Preclosing was exclusively performed using ProGlide®. Mean follow-up was 15 months. Results In all cases, stent-graft deployment was successful. There was one surgical conversion (4%; 1/25) due to bleeding from a femoral anastomosis. Two cases required additional percutaneous maneuvers (postclosing with another system in one patient and endoluminal shielding with stent-graft in the other patient). No pseudoaneurysm or access complication occurred during the follow-up. Conclusions Percutaneous access in redo groins with scar tissue and/or synthetic vascular graft using ultrasound-guided punction, preclosing with ProGlide® system and predilation with percutaneous transluminal angioplasty balloon to introduce large size sheath as used for endovascular aortic repair showed to be

  12. [Double-balloon angioplasty of pulmonary venous drainage obstruction after the Senning procedure in transposition of the great vessels].

    PubMed

    Benito Bartolomé, F; Sánchez Fernández-Bernal, C

    1999-10-01

    A six and half-year old boy with Senning operation for transposition of the great arteries, showed recurrent atrial flutter and obstruction of the pulmonary venous atrium from the early postoperative period. By Doppler examination a peak gradient of 13 mmHg at the isthmus level was recorded in the pulmonary venous atrium. A successful double-balloon dilatation of stenotic area was performed via a retrograde, transaortic, approach through angioplasty. Six months after the procedure the enlargement of the stenosis persists, and the patient is clinically asymptomatic and arrhythmia-free without medication.

  13. Prolonged high-pressure balloon angioplasty of femoropopliteal lesions: Impact on stent implantation rate and mid-term outcome

    PubMed Central

    Rigatelli, Gianluca; Palena, Mariano; Cardaioli, Paolo; dell'Avvocata, Fabio; Giordan, Massimo; Vassilev, Dobrin; Manzi, Marco

    2014-01-01

    Objectives To assess the impact on stent implantation rate and mid-term outcomes of prolonged high pressure angioplasty of femoropopliteal lesions. Methods We retrospectively enrolled 620 consecutive patients from January 2011 to December 2011 (75.6 ± 12.3 years, 355 males, 76.5% in Rutherford class 5–6), referred for critical limb ischemia and submitted to prolonged high-pressure angioplasty of femoropopliteal lesions. The definition of prolonged high-pressure angioplasty includes dilation to at least 18 atm for at least 120 s. Procedural data, and clinical and instrumental follow-up were analyzed to assess stent implantation rate and mid-term outcomes. Results The preferred approach was ipsilateral femoral antegrade in 433/620 patients (69.7%) and contralateral cross-over in 164/620 (26.4%) and popliteal retrograde + femoral antegrade in 23/620 (3.7%). Techniques included subintimal angioplasty in 427/620 patients (68.8%) and endoluminal angioplasty in 193/620 patients (31.2%). The prolonged high pressure balloon angioplasty procedure was successful in 86.2% (minor intra-procedural complications rate 15.7 %), stent implantation was performed in 74 patients (11.9%), with a significant improvement of ankle-brachial index (0.29 ± 0.6 vs. 0.88 ± 0.3, P < 00.1) and Rutherford class (5.3 ± 0.8 vs. 0.7 ± 1.9, P < 0.01), a primary patency rate of 86.7%, restenosis of 18.6 % on Doppler ultrasound and a target lesion revascularization of 14.8% at a mean follow-up of 18.1 ± 6.4 months (range 1–24 months). Secondary patency rate was 87.7%. Conclusions Prolonged high pressure angioplasty of femoropopliteal lesions appears to be safe and effective allowing for an acceptable patency and restenosis rates on mid-term. PMID:25009562

  14. Optical coherence tomography monitoring of angioplasty balloon inflation in a deployment tester

    NASA Astrophysics Data System (ADS)

    Azarnoush, Hamed; Vergnole, Sébastien; Bourezak, Rafik; Boulet, Benoit; Lamouche, Guy

    2010-08-01

    We present an innovative integration of an intravascular optical coherence tomography probe into a computerized balloon deployment system to monitor the balloon inflation process. The high-resolution intraluminal imaging of the balloon provides a detailed assessment of the balloon quality and, consequently, a technique to improve the balloon manufacturing process. A custom-built swept-source optical coherence tomography system is used for real-time imaging. A semicompliant balloon with a nominal diameter of 4 mm is fabricated for the experiments. Imaging results correspond to balloon deployment in air and inside an artery phantom. A characterization of the balloon diameter, wall thickness, compliance, and elastic modulus is provided, based on image segmentation. Using the images obtained from the probe pullback, a three-dimensional visualization of the inflated balloon is presented.

  15. Inadvertent intracoronary stent extraction 10 months after implantation complicating cutting balloon angioplasty for in-stent restenosis

    SciTech Connect

    Almeda, Francis Q.; Billhardt, Roger A

    2003-09-01

    We report the case of an unusual complication for Cutting Balloon Angioplasty (CBA) during treatment for instent restenosis (ISR), which resulted in inadvertent intracoronary stent extraction 10 months after implantation. In this case report, CBA was utilized to treat an ISR lesion in the distal right coronary artery (RCA). Due to difficulty in withdrawing the cutting balloon into the guide after treatment of the lesion, the entire system (guide, cutting balloon, and guidewire) was removed as a unit from the body. Upon examination of the system, the previously placed stent in the distal RCA was attached to the microtomes of the cutting balloon. Although the precise mechanisms for stent extraction in this case remain speculative, the initial stent used in the distal RCA may have been undersized, and this may have played a major role in this complication. Although there is limited data regarding the optimal strategy to treat the site of the inadvertent stent extraction, we opted to re-stent the area with a properly-sized coronary stent. Following the intervention, there was no residual stenosis with TIMI 3 flow through the vessel. The patient remained asymptomatic and a serum troponin drawn 18 hours after the procedure was normal, and he was discharged the next day. The interventionist must be vigilant about this rare but serious complication when applying CBA in the treatment of ISR, particularly when an undersized or underdeployed stent is suspected.

  16. Cutting balloon angioplasty for carotid artery in-stent stenosis supported by three-dimensional rotational angiography with automated vessel analysis software.

    PubMed

    Akiyama, Yasuhiko; Moritake, Kouzo; Miyazaki, Takeshi; Kowari, Kentaro; Sato, Hidetoshi; Shimada, Toshio

    2008-05-01

    In-stent stenosis is a possible long-term complication of carotid artery stenting. A simple and safe technique of cutting balloon angioplasty is described for carotid in-stent stenosis. The stented vessel is imaged by three-dimensional (3D) rotational angiography, the acquired projection images are transferred to a workstation, and the stenotic lesion and implanted stent are reconstructed. The diameter of the implanted stent in the stenotic region is measured by automated analysis software. Cutting balloon angioplasty carries the risk of vessel injury by the cutting balloon microblades, but the implanted stent acts as a barrier to protect the vessel. Therefore, cutting balloon inflation up to the stent diameter is safe and results in maximal vessel dilation. The key to success is precise measurement of the stent diameter and choice of a cutting balloon catheter of the appropriate size. 3D rotational angiography provides high-quality images of the vasculature of a stented vessel and a reference for intervention based on absolute measurements. Cutting balloon angioplasty supported by 3D rotational angiography with automated vessel analysis software should be considered as a treatment strategy for high-grade carotid artery in-stent stenosis.

  17. Sulodexide as Adjunctive Therapy in Diabetic Foot Patients With Critical Limb Ischemia Treated With Percutaneous Transluminal Angioplasty.

    PubMed

    Piaggesi, Alberto; Abbruzzese, Lorenza; Mattaliano, Chiara; Bargellini, Irene; Cicorelli, Antonello; Iacopi, Elisabetta; Lunardi, Alessandro; Coppelli, Alberto; Goretti, Chiara; Cioni, Roberto

    2014-06-01

    We evaluated the safety and efficacy of sulodexide, a biocompound of glycosamin-glicans, as adjunct medical therapy to percutaneous transluminal angioplasty (PTA) in diabetes mellitus (DM) patients with critical limb ischemia (CLI). We studied 27 consecutive DM patients with CLI successfully subjected to PTA who, on top of standard antiplatelet therapy, received sulodexide 25 mg bid, and were followed-up for 24 weeks, monitoring adverse events, transcutaneous oxygen tension (TcPO2), ankle-brachial pressure index, pain, and ulcer dimension. At the end of follow-up, ulcer healing, amputation rates, and cardiovascular risk profile of patients were evaluated. Patients were compared with a historical superimposable control group that was treated for the same indications in the same way as the study group, except for sulodexide inception. No differences in ulcer healing and amputation rates were found at the end of follow-up between the groups. In the study group, TcPO2 was significantly (P < .05) higher at the end of follow-up, and pain intensity was reduced more rapidly. Plasma fibrinogen and plasma creatinine concentration were significantly (P < .05) reduced in study group at the end of follow-up. No differences in adverse events were observed between the groups during follow-up. Our data suggest that sulodexide administration after PTA, on top of antiplatelet therapy, may improve the outcome of PTA in DM patients with CLI by improving microcirculatory function.

  18. Cutting balloon angioplasty for in-stent restenosis of the aortic coarctation in a young boy presenting with systemic hypertension of the upper extremities.

    PubMed

    Lee, Meng-Luen

    2013-12-01

    An 8.25-year-old boy was incidentally found to have systemic hypertension of the upper extremities. Blood pressures of the upper extremities were 142-150/86-98 mmHg, and those of the lower extremities 110-116/60-66 mmHg. Doppler echocardiography showed in-stent restenosis of the aortic coarctation. Traditional high-pressure balloon angioplasty failed to dilate this inveterate in-stent restenosis. Instead, a cutting balloon angioplasty was performed. The lumen was dilated from 4.80 mm to 7.89 mm. The pressure gradient dropped from 32 mmHg to 9 mmHg. Blood pressures of the upper extremities were 112-116/76-78 mmHg, and those of the lower extremities 100-104/70-72 mmHg. This paper highlights that a cutting balloon angioplasty can serve as a juste milieu to relieve in-stent restenosis of the aortic coarctation when traditional high-pressure balloon angioplasty is debatable.

  19. Absence of Bacteria on Coronary Angioplasty Balloons from Unselected Patients: Results with Use of a High Sensitivity Polymerase Chain Reaction Assay.

    PubMed

    Hansen, Gorm Mørk; Nilsson, Martin; Nielsen, Claus Henrik; Holmstrup, Palle; Helqvist, Steffen; Tolker-Nielsen, Tim; Givskov, Michael; Hansen, Peter Riis

    2015-01-01

    Periodontitis is a chronic, bacterially-induced inflammatory disease of the tooth-supporting tissues, which may result in transient bacteremia and a systemic inflammatory response. Periodontitis is associated with coronary artery disease independently of established cardiovascular risk factors, and translocation of bacteria from the oral cavity to the coronary arteries may play a role in the development of coronary artery disease. Very few studies have used angioplasty balloons for in vivo sampling from diseased coronary arteries, and with varying results. Therefore, the aim of this study was to assess if bacterial DNA from primarily oral bacteria could be detected on coronary angioplasty balloons by use of an optimized sampling process combined with an internally validated sensitive polymerase chain reaction (PCR) assay. Coronary angioplasty balloons and control samples from a total of 45 unselected patients with stable angina, unstable angina/non-ST elevation myocardial infarction, and ST-elevation myocardial infarction (n = 15 in each group) were collected and analyzed using a PCR assay with high sensitivity and specificity for 16S rRNA genes of the oral microbiome. Despite elimination of extraction and purification steps, and demonstration of sensitivity levels of 25-125 colony forming units (CFU), we did not detect bacterial DNA from any of the coronary angioplasty balloons. A subsequent questionnaire indicated that the prevalence of periodontitis in the study cohort was at least 39.5%. Although coronary angioplasty balloons are unlikely to be useful for detection of bacteria with current PCR techniques in unselected patients with coronary artery disease, more studies are warranted to determine the extent to which bacteria contribute to atherosclerosis and its clinical manifestations and whether the presence of bacteria in the arteries is a transient phenomenon.

  20. Thermal laser-assisted angioplasty of renal artery stenosis for renovascular hypertension.

    PubMed

    Tani, M; Mizuno, K; Midorikawa, H; Igari, T; Egawa, M; Niimura, S; Fukuchi, S; Hoshino, S

    1993-01-01

    Percutaneous transluminal laser-assisted angioplasty of a renal artery stenosis was performed in a 16-year-old woman with renovascular hypertension. The stenotic portion of the renal artery was predilated by delivering Nd-YAG laser energy to the terminal tip of a laser catheter. Although the luminal diameter did not increase sufficiently with laser angioplasty alone, it allowed passage of the balloon catheter and subsequent successful balloon angioplasty. Immediately after dilatation, the patient's blood pressure fell to normal, and plasma renin activity decreased. There were no serious complications. Thermal laser angioplasty seems to be an effective adjunct technique for the treatment of severe renal artery stenosis which does not allow initial passage of a balloon catheter.

  1. Endovascular Stenting for Restenosis of the Intracranial Vertebrobasilar Artery After Balloon Angioplasty: Two Case Reports and Review of the Literature

    SciTech Connect

    Kiyosue, Hiro Okahara, Mika; Yamashita, Masanori; Nagatomi, Hirofumi; Nakamura, Natsuki; Mori, Hiromu

    2004-09-15

    Percutaneous transluminal balloon angioplasty (PTA) has been used in the treatment of critical stenosis of the intracranial vertebrobasilar artery (VBA). PTA of the intracranial VBA carries the risk of fatal complications such as arterial dissection or acute occlusion as well as postoperative restenosis. The estimated risk of periprocedural complications and restenosis were approximately 20% and 27%. The use of recently developed stents could prevent these problems of PTA. We present two cases of restenosis of the intracranial VBA after PTA which stenoses were successfully retreated with endovascular stenting using flexible coronary stents without any complications. Neither restenosis nor other recurrent symptoms were observed during the 4- and 6-month follow-up period. Reviewing the literature of 33 cases and our 2 cases, the overall complication rates related to stenting and restenosis were 5.6% and 7.8%. Endovascular stenting for the treatment of intracranial VBA can reduce the risk of arterial dissection and restenosis.

  2. The role of "cutting" balloon angioplasty for the treatment of short femoral bifurcation steno-obstructive disease.

    PubMed

    Cotroneo, Antonio Raffaele; Iezzi, Roberto

    2010-10-01

    This study was designed to report our experience with "cutting" balloon angioplasty (CBA) for the treatment of short femoral bifurcation arterial stenosis. Between March 2005 and September 2007, 18 consecutive patients who were high-risk for surgery with critical limb ischemia or severe lifestyle-limiting claudication underwent "cutting" balloon angioplasty (4-6 mm diameter/15-20-mm length) for the treatment of 27 focal (<3 cm) severe fibro-calcified stenosis of the common femoral artery (n = 14) and/or the proximal part of the superficial femoral artery (n = 6) or profunda femoris (n = 7). Baseline patient demographic data, pre- and post-procedural patient clinical data, and procedural results were recorded. Follow-up consisted of clinical check-up and color duplex ultrasonography (CDU) examination 1, 3, 6, 12, and 18 months after the procedure. All endovascular treatments were successfully performed with clinical success obtained for all patients. No complications occurred during all treatments and no patient required surgical conversion or placement of a stent because of recoil, dissection, or arterial tears. No acute vessel closure was registered. During a mean follow-up of 9.4 (range, 6-18) months, endovascular treatment (CBA) was performed for restenosis/occlusion of seven lesions (25.9%) in four patients, whereas surgical treatment (endarterectomy with patch) for restenosis/occlusion of three lesions (11.1%) was performed in two patients with a consequent reintervention rate of 37%. Primary and secondary patency rates were 84.6 and 88.4% at 6 months and 57.9 and 79.6% at 12 months, respectively. No major limb amputation was performed, with a 12-month limb salvage rate of 88.9%. CBA seems to be a valuable tool for the endovascular treatment of focal femoral bifurcation stenotic lesions for patients who are poor candidates for surgery.

  3. Simulation of balloon angioplasty in residually stressed blood vessels-Application of a gradient-enhanced fibre damage model.

    PubMed

    Polindara, César; Waffenschmidt, Tobias; Menzel, Andreas

    2016-08-16

    In this contribution we study the balloon angioplasty in a residually stressed artery by means of a non-local gradient-enhanced fibre damage model. The balloon angioplasty is a common surgical intervention used to extend or reopen narrowed blood vessels in order to restore the continuous blood flow in, for instance, atherosclerotic arteries. Inelastic, i.e. predominantly damage-related and elastoplastic processes are induced in the artery during its inflation resulting in an irreversible deformation. As a beneficial consequence, provided that the inelastic deformations do not exceed a specific limit, higher deformations can be obtained within the same pressure level and a continuous blood flow can be guaranteed. In order to study the mechanical response of the artery in this scenario, we make use of the non-local gradient-enhanced model proposed in Waffenschmidt et al. (2014). In this contribution, we extend this model to make use of an incompressible format in connection with a Q1Q1P0 finite element implementation. The residual stresses in the artery are also taken into account following the framework presented in Waffenschmidt (2015). From the results it becomes apparent that, when the artery is subjected to radial stresses beyond the physiological range, damage evolution is triggered in the collagen fibres. The impact of the residual stresses on the structural response and on the circumferential stress distribution along the thickness of the arterial wall is also studied. It is observed that the residual stresses have a beneficial effect on the mechanical response of the arterial wall.

  4. Elastic Recoil after Balloon Angioplasty in Hemodialysis Accesses: Does It Actually Occur and Is It Clinically Relevant?

    PubMed

    Rajan, Dheeraj K; Sidhu, Arshdeep; Noel-Lamy, Maxime; Mahajan, Ashish; Simons, Martin E; Sniderman, Kenneth W; Jaskolka, Jeffrey; Tan, Kong Teng

    2016-06-01

    Purpose To qualify and quantify elastic recoil and determine its effect on access patency. Materials and Methods Research ethics board approval was obtained and all patients signed an informed consent form. This was a prospective, nonrandomized study of mature accesses that underwent balloon percutaneous transluminal angioplasty (PTA) between January 2009 and December 2012. After PTA, completion fistulography was performed at 0-, 5-, 10-, and 15-minute intervals. From Digital Imaging and Communications in Medicine images, percentage of lesion stenosis before and after PTA was measured at each time point. A total of 76 patients (44 men, 32 women; mean age, 59.6 years) were enrolled and underwent 154 PTAs in 56 grafts and 98 fistulas. Venous elastic recoil was defined as recurrent luminal narrowing greater than 50% within 15 minutes after full effacement of the stenosis by the angioplasty balloon. Data collected included sex, age, access type and location, lesion location, length, and time to next intervention. Access patency was estimated by using Kaplan-Meier survival method, association of variables with the risk of loss of patency was assessed by using a Cox proportional hazards model, and a multiple variable model was examined by considering all variables. Results Technical success of PTA with less than 30% residual stenosis was 78%. By 15 minutes, 15.6% (24 of 154) of treated lesions recurrently narrowed by more than 50%, with a majority observed at 5 minutes (15 of 24). Technical failure of PTA was predictive of elastic recoil (P < .001), as was cephalic arch stenosis in fistulas (P = .047) and autogenous fistulas (P = .04). Elastic recoil, when it did occur, did not influence patency. Six-month primary patency was 34.8% in grafts and 47.1% in fistulas. Conclusion Venous elastic recoil after PTA of stenoses in hemodialysis access circuits is common, but its occurrence does not influence access primary patency after PTA. (©) RSNA, 2015.

  5. The Role of 'Cutting' Balloon Angioplasty for the Treatment of Short Femoral Bifurcation Steno-Obstructive Disease

    SciTech Connect

    Cotroneo, Antonio Raffaele; Iezzi, Roberto

    2010-10-15

    This study was designed to report our experience with 'cutting' balloon angioplasty (CBA) for the treatment of short femoral bifurcation arterial stenosis. Between March 2005 and September 2007, 18 consecutive patients who were high-risk for surgery with critical limb ischemia or severe lifestyle-limiting claudication underwent 'cutting' balloon angioplasty (4-6 mm diameter/15-20-mm length) for the treatment of 27 focal (<3 cm) severe fibro-calcified stenosis of the common femoral artery (n = 14) and/or the proximal part of the superficial femoral artery (n = 6) or profunda femoris (n = 7). Baseline patient demographic data, pre- and post-procedural patient clinical data, and procedural results were recorded. Follow-up consisted of clinical check-up and color duplex ultrasonography (CDU) examination 1, 3, 6, 12, and 18 months after the procedure. All endovascular treatments were successfully performed with clinical success obtained for all patients. No complications occurred during all treatments and no patient required surgical conversion or placement of a stent because of recoil, dissection, or arterial tears. No acute vessel closure was registered. During a mean follow-up of 9.4 (range, 6-18) months, endovascular treatment (CBA) was performed for restenosis/occlusion of seven lesions (25.9%) in four patients, whereas surgical treatment (endarterectomy with patch) for restenosis/occlusion of three lesions (11.1%) was performed in two patients with a consequent reintervention rate of 37%. Primary and secondary patency rates were 84.6 and 88.4% at 6 months and 57.9 and 79.6% at 12 months, respectively. No major limb amputation was performed, with a 12-month limb salvage rate of 88.9%. CBA seems to be a valuable tool for the endovascular treatment of focal femoral bifurcation stenotic lesions for patients who are poor candidates for surgery.

  6. Long-Term Follow-Up of Percutaneous Balloon Angioplasty in Adult Aortic Coarctation

    SciTech Connect

    Paddon, Alex J.; Nicholson, Anthony A.; Ettles, Duncan F.; Travis, Simon J.; Dyet, John F.

    2000-09-15

    Purpose: To assess long-term outcomes following percutaneous transluminal angioplasty (PTA) of congenital aortic coarctation in adults.Methods: Seventeen patients underwent PTA for symptomatic adult coarctation of the aorta. Sixteen patients, with a mean age of 28 years (range 15-60 years), were reviewed at a mean interval after angioplasty of 7.3 years (range 1.5-11 years). Assessment included magnetic resonance imaging (MRI), Doppler echocardiography, and clinical examination. Current clinical measurements were compared with pre- and immediate post-angioplasty measurements.Results: At follow-up 16 patients were alive and well. The patient not included in follow-up had undergone surgical repair and excision of the coarctation segment following PTA. Mean brachial systolic blood pressure for the group decreased from 174 mmHg before angioplasty to 130 mmHg at follow-up (p 0.0001). The mean gradient had fallen significantly from 50.9 to 17.8 at follow-up (p = 0.001). The average number of antihypertensive drugs required per patient decreased from 0.56 to 0.31 (p = 0.234). No significant residual stenoses or restenoses were seen at MRI. Small but clinically insignificant residual pressure gradients were recorded in all patients using Doppler echocardiography. Complications included one transient ischemic attack at 5 days, one external iliac dissection requiring stent insertion, and a further patient who developed a false aneurysm close to the coarctation site at 12 months which subsequently required surgical excision.Conclusion: PTA of adult coarctation is safe and effective in the long term. Although primary stenting has recently been advocated in the treatment of this condition, our results suggest that PTA remains the treatment of choice.

  7. Insertion of Self-Expandable Nitinol Stents Without Previous Balloon Angioplasty Reduces Restenosis Compared with PTA Prior to Stenting

    SciTech Connect

    Harnek, Jan; Zoucas, Evita; Stenram, Unne; Cwikiel, Wojciech

    2002-10-15

    Purpose: To compare the development of intimal hyperplasia after deployment of a self-expanding nitinol stent with and without previous percutaneous transluminal balloon angioplasty (PTA), with the results after PTA alone. Methods: In nine healthy pigs, the iliac arteries were divided into three groups: group 1 (n = 6 arteries) was treated with PTA; group 2 n 6)with insertion of self-expanding stents after PTA; and group 3 (n = 6) with stent insertion without previous PTA. After 8 weeks the vessels were examined with intravascular ultrasonography,histologic examination and morphometric analysis. Results: Although the injury index in group 1 (0.17{+-} 0.57) was lower (p <0.05) than in group 2 (0.26 {+-} 0.06) and group 3 (0.26 {+-} 0.08), PTA-treated arteries showed significantly (p <0.05) reduced mean luminal gain (0.53 {+-} 2.84) compared with arteries treated with PTA prior to stenting (2.58 {+-} 1.38) and compared with stenting alone (4.65 {+-}5.34). Stenting after PTA resulted in a higher (p<0.05) restenosis index (2.63 {+-} 1.06) compared with stenting without PTA (1.35 {+-} 0.59). Group 2 also had a significantly thicker intimap <0.05) and 83% and 74% higher intima/mediaratio (p <0.05) compared with groups 1 and 3, respectively. Conclusion: Insertion of a self-expandable nitinol stent without previous PTA results in less intimalhyperplasia than if PTA is performed prior to stenting, suggesting that direct stenting can be used in angioplasty sessions with a favorable outcome.

  8. A three-dimensional quantitative analysis of restenosis parameters after balloon angioplasty: comparison between semi-automatic computer-assisted planimetry and stereology.

    PubMed

    Salu, Koen J; Knaapen, Michiel W M; Bosmans, Johan M; Vrints, Chris J; Bult, Hidde

    2002-01-01

    Semi-automatic computer-assisted planimetry is often used for the quantification of restenosis parameters after balloon angioplasty although it is a time-consuming method. Moreover, slicing the artery to enable analysis of two-dimensional (2-D) images leads to a loss of information since the vessel structure is three-dimensional (3-D). Cavalieri's principle uses systematic random sampling allowing 3-D quantification. This study compares the accuracy and efficiency of planimetry versus point-counting measurements on restenosis parameters after balloon angioplasty and investigates the use of Cavalieri's principle for 3-D volume quantification. Bland and Altman plots showed good agreement between planimetry and point counting for the 2-D and 3-D quantification of lumen, internal elastic lamina (IEL) and external elastic lamina (EEL), with a slightly smaller agreement for intima and media. Mean values and induced coefficients of variation were similar for both methods for all parameters. Point counting induced a 6% error in its 3-D quantification, which is negligible in view of the biological variation (>90%) among animals. However, point counting was 3 times faster compared to planimetry, improving its efficiency. This study shows that combining Cavalieri's principle with point counting is a precise and efficient method for the 3-D quantification of restenosis parameters after balloon angioplasty.

  9. Network meta-analysis of balloon angioplasty, nondrug metal stent, drug-eluting balloon, and drug-eluting stent for treatment of infrapopliteal artery occlusive disease

    PubMed Central

    Xiao, Yaowen; Chen, Zhong; Yang, Yaoguo; Kou, Lei

    2016-01-01

    PURPOSE We aimed to conduct a network meta-analysis of mixed treatments for the infrapopliteal artery occlusive disease. METHODS We searched randomized controlled trials (RCTs) regarding balloon angioplasty (BA), nondrug metal stent (NDMS), drug-eluting balloon (DEB), or drug-eluting stent (DES) in PubMed, Embase, CENTRAL, Ovid, Sinomed, and other relevant websites. We selected and assessed the trials that met the inclusion criteria and conducted a network meta-analysis using the ADDIS software. RESULTS We included 11 relevant trials. We analyzed data of 1322 patients with infrapopliteal artery occlusive disease, of which 351 were in the NDMS vs. DES trials, 231 in the NDMS vs. BA trials, 490 in the BA vs. DEB trials, 50 in the DEB vs. DES trials, and 200 in the BA vs. DES trials. The network meta-analysis indicated that with NDMS as the reference, DES had a better result with respect to restenosis (odds ratio [OR], 5.16; 95% credible interval [CI], 1.58–18.41; probability of the best treatment, 84%) and amputation (OR, 2.50; 95% CI, 0.81–7.11; probability of the best treatment, 61%) and DEB had a better result with respect to target lesion revascularization (TLR; OR, 3.74; 95% CI, 0.78–17.05; probability of the best treatment, 57%). Moreover, with BA as the reference, NDMS had a better result with respect to technical success (OR, 0.10; 95% CI, 0.00–1.15; probability of the best treatment, 86%). CONCLUSION Our meta-analysis revealed that DES is a better treatment with respect to short-term patency and limb salvage rate, NMDS may provide a better technical success, and DEB and DES are good choices for reducing revascularization. PMID:27559766

  10. Post-Dilatation Intravascular Brachytherapy Trials on Hypercholesterolemic Rabbits Using {sup 32}P-Phosphate Solutions in Angioplasty Balloons

    SciTech Connect

    Walichiewicz, Piotr Wilczek, Krzysztof; Petelenz, Barbara; Jachec, Wojciech; Jochem, Jerzy; Tomasik, Andrzej; Bilski, Pawel; Gaca, Pawel; Banaszczuk, Joanna; Ihnatowicz, Jerzy; Wodniecki, Jan

    2004-01-15

    Response of peripheral arteries to post-dilatation intravascular brachytherapy (IVBT) using {sup 32}P liquid sources was studied in a rabbit model. The applied sources were angioplasty balloons filled with aqueous solutions of Na{sub 2}H{sup 32}PO{sub 4}, NaCl and iodinated contrast. Dose distribution was calibrated by thermoluminescence dosimetry. The uncertainty of in vitro determinations of the activity-dose dependence was {+-} 15-30%. The animal experiments were performed on rabbits with induced hypercholesterolemia. The {sup 32}P sources were introduced into a randomly chosen (left or right) iliac artery, immediately after balloon injury. Due to the low specific activity of the applied sources, the estimated 7-49 Gy doses on the internal artery surface required 30-100 min irradiations. A symmetric, balloon-occluded but non-irradiated artery of the same animal served as control. Radiation effects were evaluated by comparing the thicknesses of various components of irradiated versus untreated artery walls of each animal. The treatment was well tolerated by the animals. The effects of various dose ranges could be distinguished although differences in individual biological reactions were large. Only the 49 Gy dose at 'zero' distance (16 Gy at 1.0 mm from the balloon surface) reduced hypertrophy in every active layer of the artery wall. The cross-sectional intimal thicknesses after 7, 12, 38 and 49 Gy doses were 0.277, 0.219, 0.357 and 0.196 mm{sup 2} respectively, versus 0.114, 0.155, 0.421 and 0.256 mm{sup 2} in controls (p < 0.05). The lowest radiation dose on the intima induced the opposite effect. Edge intimal hyperplasia was not avoided, which agrees with other reports. The edge restenosis and the variability of individual response to identical treatment conditions must be considered as limitations of the post-dilatation IVBT method. Only application of highest irradiation doses was effective. The irradiation dose should be planned and calculated for

  11. Differences in Endothelial Injury After Balloon Angioplasty, Insertion of Balloon-Expanded Stents or Release of Self-Expanding Stents: An Electron Microscopic Experimental Study

    SciTech Connect

    Harnek, Jan; Zoucas, Evita; Carlemalm, Erik; Cwikiel, Wojciech

    1999-01-15

    Purpose: To evaluate which of six different commonly available stents inserted into an artery without percutaneous transluminal angioplasty (PTA) causes the least endothelial damage. To compare the degree of endothelial injury after insertion of such a stent with injury caused by PTA. Methods: Twelve healthy pigs were used in the experiments. In the first part of the study six different types of stents were inserted into the common iliac arteries. In the second part of the study self-expanding stents with large spaces between the wires were used. PTA was performed in the contralateral iliac artery. The pigs were killed immediately after the procedure and resected specimens examined after fixation, using scanning electron microscopy. Results: All procedures but two were accomplished successfully. More endothelium was preserved after insertion of self-expanding stents with large spaces between the wires, compared with stents with small spaces and balloon-expanded stents. After insertion of self-expanding stents with large spaces, 50.1% {+-} 16.4% of the endothelium remained intact, compared with only 5.6% {+-} 7.7% after PTA. The difference was statistically significant (p < 0.001). Conclusion: Self-expanding stents with large spaces between the wires, inserted without PTA, cause less damage to the endothelium than other stents and significantly less damage than PTA.

  12. Acute effects of short-term intimal heating by laser-heated thermal balloon angioplasty in canine stenotic femoral arteries in vivo

    NASA Astrophysics Data System (ADS)

    Miyamoto, Akira; Sakurada, Masami; Arai, Tsunenori; Mizuno, Kyoichi; Sugiyabu, Yasunori; Kurita, Akira; Nakamura, Haruo; Kikuchi, Makoto; Watanabe, Tamishige; Utsumi, Atsushi; Akai, Yoshiro; Takeuchi, Kiyoshi

    1993-06-01

    Short-term intimal heating may be effective to improve luminal geometry without deep medial injury which can induce restenosis. We developed a new laser-heated thermal balloon catheter which can quickly raise and lower the balloon temperature. To investigate the acute effect of short-term thermal balloon angioplasty (STBA) for stenotic lesions, we performed STBA following balloon angioplasty (BA) in 8 canine stenotic femoral arteries. Cw Nd:YAG laser delivery (10 W, 15 s) induced the maximum temperature of 83 degree(s)C on average. Angiography and angioscopy were performed at pre-BA, post-BA and post-STBA. The angiographical mean stenotic diameter was 1.8 mm at pre-BA, 2.2 mm* at post-BA, 2.9 mm** at post-STBA (*:p < 0.05 pre-BA vs post-BA, **:p < 0.05 pre- and post-BA vs post-STBA). The angioscopic observation revealed intimal flaps and tears in 7 lesions after BA. The luminal geometry after STBA was symmetrically expanded. However, the intimal injury was still observed although the intimal flaps were partly sealed by STBA. These results suggested that the dilatation mechanism of STBA for stenotic lesions might be attributed to preventing elastic recoil rather than to sealing intimal fragments induced by BA.

  13. Laser Angioplasty

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The principal method of dealing with coronary artery blockage is bypass surgery. A non-surgical alternative available to some patients is balloon angioplasty. For several years, medical researchers have been exploring another alternative that would help a wider circle of patients than the balloon treatment and entail less risk than bypass surgery. A research group is on the verge of an exciting development: laser angioplasty with a 'cool' type of laser, called an excimer laser, that does not damage blood vessel walls and offers non-surgical cleansing of clogged arteries with extraordinary precision. The system is the Dymer 200+ Excimer Laser Angioplasty System, developed by Advanced Intraventional Systems. Used in human clinical tests since 1987, the system is the first fully integrated 'cool' laser capable of generating the requisite laser energy and delivering the energy to target arteries. Thirteen research hospitals in the U.S. have purchased Dymer 200+ systems and used them in clinical trials in 121 peripheral and 555 coronary artery cases. The success rate in opening blocked coronary arteries is 85 percent, with fewer complications than in balloon angioplasty. Food and Drug Administration approval for the system is hoped for in the latter part of 1990. * Advanced Intraventional Systems became Spectranetics in 1994 and discontinued the product.

  14. Iatrogenic aortopulmonary fistula occurring after pulmonary artery balloon angioplasty: a word of caution.

    PubMed

    Vida, Vladimiro L; Biffanti, Roberta; Stellin, Giovanni; Milanesi, Ornella

    2013-06-01

    We describe the natural history of an adolescent patient who developed an aortopulmonary fistula (APF) after transcatheter stent placement for left pulmonary artery stenosis after neonatal repair of d-transposition of the great arteries. Due to its rarity, the APF was not initially diagnosed and treated until 4 months later. The APF was occluded with a covered stent. Because this is not an isolated report in the literature, we believe it should be considered as a potential complication in all patients after balloon dilation of stenotic pulmonary artery branches after arterial switch surgery.

  15. Excimer laser coronary angioplasty: relative risk analysis of clinical results

    NASA Astrophysics Data System (ADS)

    Bittl, John A.

    1992-08-01

    Reports of successful use of excimer laser coronary angioplasty for complex coronary artery disease abound, yet firm indications for its use have not been defined. We attempted to treat 858 coronary stenoses in 764 consecutive patients (mean age 61 years; range 32 - 91 years; 75% men; 76% with Class III or IV angina) with excimer laser angioplasty at 308 nm. Successful treatment was achieved in 86% of patients, as indicated by angioplasty, we used relative risk analysis. This showed that certain angiographic features, such as lesions at a vessel bifurcation (odds ratio, OR equals 0.46; 95% confidence interval 0.23, 0.88; P equals 0.017;) or in a tortuous segment (OR equals 0.54; 95% CI equals 0.34, 0.88; P equals 0.041), have decreased likelihood of clinical success. On the other hand, ostial stenoses (OR equals 1.06; 95% CI equals 0.44, 2.56, P equals 0.903) and saphenous vein graft lesions (OR equals 2.17; 95% CI equals 0.98, 4.82; P equals 0.051) have acceptable success rates. Diffuse disease (> 20 mm), total occlusions and calcified lesions were treated as successfully as all other lesion types. Successful treatment with excimer laser coronary angioplasty was also achieved in almost all patients (15/16) who had a prior unsuccessful attempt at balloon angioplasty in the lesion was crossed with a guidewire yet resists either balloon catheter passage or full dilatation. Follow-up angiography was obtained in 70% of eligible patients. Angiographic restenosis, defined by > 50% stenosis, was seen in 60% of patients. Relative risk analysis showed an increased risk of restenosis when adjunctive balloon angioplasty was not used (OR equals 1.68; 95% CI equals 1.02, 2.28; P equals 0.039). Other variables known to affect the outcome of balloon angioplasty, such as lesion length or stenosis in degenerated saphenous vein bypass graft, did not influence the

  16. Study for prevention of proliferation of smooth muscle cells after balloon angioplasty using Ho:YAG laser-induced acoustic wave

    NASA Astrophysics Data System (ADS)

    Suga, Eriko; Yamashita, Erika; Futami, Hikaru; Arai, Tsunenori

    2004-07-01

    We designed the method for prevention of restenosis after balloon angioplasty using laser-induced bubble-collapse acoustic wave. This study was performed to evaluate the effect on smooth muscle cells (SMCs) by Ho:YAG laser (λ=2.10μm)-induced acoustic wave, in vitro and in vivo. The laser energy was delivered by a silica glass fiber into water. Sound pressure was measured with a hydrophone changing the laser energy. The laser-induced acoustic wave was loaded to SMCs in vitro. This acoustic effect on SMCs was measured by MTT assay. The acoustic wave loaded SMCs were controllably injured with the laser energy and laser shots. The balloon denudated rabbit aorta was used to evaluate in vivo effect. The laser-induced acoustic wave loaded aorta was extracted at 42 days after the laser irradiation, and was examined by Hematoxylin-Eosin staining. We found that the laser irradiation of 20 pulses with 60mJ/pulse prevented SMCs proliferation. We think the mechanism of this effect might be same as brachytherapy. We demonstrated the applicability of Ho:YAG laser-induced acoustic wave against vascular restenosis after balloon angioplasty.

  17. Utility of birefringence changes due to collagen thermal denaturation rate process analysis: vessel wall temperature estimation for new short term heating balloon angioplasty

    NASA Astrophysics Data System (ADS)

    Kaneko, Kenji; Shimazaki, Natsumi; Gotoh, Maya; Nakatani, Eriko; Arai, Tsunenori

    2007-02-01

    Our photo thermal reaction heating architecture balloon realizes less than 10 s short term heating that can soften vessel wall collagen without damaging surrounding tissue thermally. New thermal balloon angioplasty, photo-thermo dynamic balloon angioplasty (PTDBA) has experimentally shown sufficient opening with 2 atm low pressure dilation and prevention of chronic phase restenosis and acute phase thrombus in vivo. Even though PTDBA has high therapeutic potential, the most efficient heating condition is still under study, because relationship of treatment and thermal dose to vessel wall is not clarified yet. To study and set the most efficient heating condition, we have been working on establishment of temperature history estimation method from our previous experimental results. Heating target of PTDBA, collagen, thermally denatures following rate process. Denaturation is able to be quantified with measured collagen birefringence value. To express the denaturation with equation of rate process, the following ex vivo experiments were performed. Porcine extracted carotid artery was soaked in two different temperature saline baths to enforce constant temperature heating. Higher temperature bath was set to 40 to 80 degree Celsius and soaking duration was 5 to 40 s. Samples were observed by a polarizing microscope and a scanning electron microscope. The birefringence was measured by polarizing microscopic system using Brace-Koehler compensator 1/30 wavelength. The measured birefringence showed temperature dependency and quite fit with the rate process equation. We think vessel wall temperature is able to be estimated using the birefringence changes due to thermal denaturation.

  18. Mid-infrared coronary laser angioplasty with multifiber catheters

    NASA Astrophysics Data System (ADS)

    White, Christopher J.; Ramee, Stephen R.; Collins, Tyrone J.

    1993-06-01

    Mid-infrared laser wavelengths offer advantages as a source for coronary angioplasty based upon the excellent fiberoptic transmission and the enhanced tissue absorption of these photons. We report the results of a pilot clinical trial of a Holmium:YAG (2.1 micrometers ) coronary laser angioplasty using a prototype (1.6 mm and 2.0 mm) multifiber catheters. Coronary laser angioplasty with or without adjunctive balloon angioplasty or directional atherectomy was performed in 14 patients with 17 coronary stenoses. Laser success was obtained in 13/14 (93%) patients and 16/17 (94%) lesions. Uncomplicated procedural success was achieved in 9/14 (64%) patients and 12/17 (71%) lesions. Our initial laser success rate was very encouraging using this prototype multifiber catheter with a holmium:YAG laser. However, our overall procedural success rate was disappointing, and not superior to that expected with conventional angioplasty alone. The holmium laser remains an attractive energy source for laser angioplasty, but its utility is limited by catheters which create inadequate channels for stand-alone laser angioplasty.

  19. Common Iliac Artery Thrombosis following Pelvic Surgery Resulting in Kidney Allograft Failure Successfully Treated by Percutaneous Transluminal Angioplasty with Balloon-Expandable Covered Stent

    PubMed Central

    Golla, Maheswara S.; Acharjee, Subasit; Jaber, Bertrand L.; Garcia, Lawrence A.

    2015-01-01

    We report the case of a 66-year-old woman who developed acute kidney allograft failure due to thrombotic occlusion of the common iliac artery after hysterectomy requiring emergent allograft rescue. She underwent percutaneous transluminal angioplasty with endovascular balloon expandable covered stent graft placement in the right common iliac artery. Although there are a handful of case reports of acute limb ischemia secondary to acute common iliac artery thrombosis, this is the first case reported in the literature resulting in successful kidney allograft rescue following pelvic surgery. PMID:26355669

  20. Focused force angioplasty Theory and application

    SciTech Connect

    Solar, Ronald J.; Ischinger, Thomas A

    2003-03-01

    Focused force angioplasty is a technique in which the forces resulting from inflating an angioplasty balloon in a stenosis are concentrated and focused at one or more locations within the stenosis. While the technique has been shown to be useful in resolving resistant stenoses, its real value may be in minimizing the vascular trauma associated with balloon angioplasty and subsequently improving the outcome.

  1. Balloons in endovascular neurosurgery: history and current applications.

    PubMed

    Alaraj, Ali; Wallace, Adam; Dashti, Reza; Patel, Prasad; Aletich, Victor

    2014-02-01

    The use of balloons in the field of neurosurgery is currently an essential part of our clinical practice. The field has evolved over the last 40 years since Serbinenko used balloons to test the feasibility of occluding cervical vessels for intracranial pathologies. Since that time, indications have expanded to include sacrificing cervical and intracranial vessels with detachable balloons, supporting the coil mass in wide-necked aneurysms (balloon remodeling technique), and performing intracranial and cervical angioplasty for atherosclerotic disease, as well as an adjunct to treat arteriovenous malformations. With the rapid expansion of endovascular technologies, it appears that the indications and uses for balloons will continue to expand. In this article, we review the history of balloons, the initial applications, the types of balloons available, and the current applications available for endovascular neurosurgeons.

  2. Adventitial Nab-Rapamycin Injection Reduces Porcine Femoral Artery Luminal Stenosis Induced by Balloon Angioplasty via Inhibition of Medial Proliferation and Adventitial Inflammation

    PubMed Central

    Gasper, Warren J.; Jimenez, Cynthia A.; Walker, Joy; Conte, Michael S.; Seward, Kirk; Owens, Christopher D.

    2014-01-01

    Background Endovascular interventions on peripheral arteries are limited by high rates of restenosis. Our hypothesis was that adventitial injection of rapamycin nanoparticles would be safe and reduce luminal stenosis in a porcine femoral artery balloon angioplasty model. Methods and Results Eighteen juvenile male crossbred swine were included. Single-injury (40%–60% femoral artery balloon overstretch injury; n=2) and double-injury models (endothelial denudation injury 2 weeks before a 20%–30% overstretch injury; n=2) were compared. The double-injury model produced significantly more luminal stenosis at 28 days, P=0.002, and no difference in medial fibrosis or inflammation. Four pigs were randomized to the double-injury model and adventitial injection of saline (n=2) or 500 μg of nanoparticle albumin-bound rapamycin (nab-rapamycin; n=2) with an endovascular microinfusion catheter. There was 100% procedural success and no difference in endothelial regeneration. At 28 days, nab-rapamycin led to significant reductions in luminal stenosis, 17% (interquartile range, 12%–35%) versus 10% (interquartile range, 8.3%–14%), P=0.001, medial cell proliferation, P<0.001, and fibrosis, P<0.001. There were significantly fewer adventitial leukocytes at 3 days, P<0.001, but no difference at 28 days. Pharmacokinetic analysis (single-injury model) found rapamycin concentrations 1500× higher in perivascular tissues than in blood at 1 hour. Perivascular rapamycin persisted ≥8 days and was not detectable at 28 days. Conclusions Adventitial nab-rapamycin injection was safe and significantly reduced luminal stenosis in a porcine femoral artery balloon angioplasty model. Observed reductions in early adventitial leukocyte infiltration and late medial cell proliferation and fibrosis suggest an immunosuppressive and antiproliferative mechanism. An intraluminal microinfusion catheter for adventitial injection represents an alternative to stent- or balloon-based local drug delivery

  3. Local Administration of NF-{kappa} B Decoy Oligonucleotides to Prevent Restenosis after Balloon Angioplasty: An Experimental Study in New Zealand White Rabbits

    SciTech Connect

    Kalinowski, Marc Viehofer, Kerstin; Hamann, Christine; Barry, James J.; Kleb, Beate; Klose, Klaus Jochen; Wagner, Hans-Joachim; Alfke, Heiko

    2005-04-15

    Purpose. To evaluate the efficacy of NF-{kappa} B oligonucleotides (ODN) administered by local administration with the channeled balloon catheter to prevent restenosis after balloon angioplasty in restenotic iliac arteries of New Zealand white rabbits. Materials and Methods. In vitro, 8000 rabbit vascular smooth muscle cells (rVSMC) where transfected with a liposomal carrier (TfX50) with 100 ng of decoy and scrambled ODN. Inhibition of proliferation was measured using a MTT assay after 24 hours in comparison to control. In vivo, 22 male New Zealand White rabbits were fed a 1% cholesterol diet and received denudation of both common iliac arteries with a 3 mm balloon catheter to induce an arterial stenosis. Four weeks after stenosis induction, local application of NF-{kappa} B in two different concentrations (1 {mu}g: n = 14; 10 {mu}g: n = 8) was performed randomly on one common iliac artery. Scrambled oligonucleotides without specific binding capacities were injected into the contralateral side. The channeled balloon catheter allows simultaneous balloon dilation (8 atm) of the stenosis and local application of a drug solution (2 atm). Four weeks after local drug delivery the animals were killed and the vessels were excised and computerized morphometric measurements were performed. Results. NF-{kappa} B decoy ODN but not scrambled ODN inhibited proliferation of rVSMC in vitro. Following local ODN application in the animals, no acute vascular complications were seen. NF-{kappa} B ODN resulted in a statistically non significant reduction of neointimal area compared to the control group. The neointimal area was 0.97 mm{sup 2} using 1 {mu}g NF-{kappa} B ODN compared to 0.98 mm{sup 2} in the control group. The higher dose resulted in a neointimal area of 0.97 mm{sup 2} compared to 1.07mm{sup 2} at the control side. Conclusions. Local drug delivery of NF-{kappa} B ODN using the 'channeled balloon' catheter could not reduce neointimal hyperplasia in stenostic rabbit iliac

  4. Acute embolic occlusion of the right common iliac artery after revision total hip arthroplasty treated with catheter-directed thrombolysis and balloon angioplasty: A case report

    PubMed Central

    Yang, Hongqi; Chen, Song; Chen, Li; Li, Yuefeng; Chai, Yasheng; Wei, Ping; Xu, Shunchi; Liu, Tangyou; Liu, Feng; Zhang, Zhuo

    2015-01-01

    Methods: A 63-year-old woman with atrial fibrillation presented clinical symptoms and signs of acute ischemia in the right lower extremity on the 17th postoperative day after revision total hip arthroplasty of the left hip for aseptic loosening of femoral component. Aspirin was discontinued 7 days before surgery. Both computed tomography angiography and digital subtraction angiography demonstrated complete occlusion of the right common iliac artery. An emergency catheter-directed thrombolysis with urokinase combined with balloon angioplasty was performed to obtain complete patency of the right common iliac artery. Results: The patient received anticoagulation and antiplatelet therapy postoperatively and was fine at the 2-year follow-up. Conclusions: This case demonstrated that catheter-directed thrombolysis combined with balloon angioplasty could be an efficacious, minimally invasive approach for the treatment of acute embolic occlusion of the common iliac artery. Preoperative anticoagulation for patients undergoing total hip arthroplasty with long-term use of aspirin for atrial fibrillation needs further investigation. PMID:27489692

  5. Temporary Arterial Balloon Occlusion as an Adjunct to Yttrium-90 Radioembolization

    SciTech Connect

    Hagspiel, Klaus D.; Nambiar, Ashwin; Hagspiel, Lauren M.; Ahmad, Ehab Ali; Bozlar, Ugur

    2013-06-15

    Purpose. This study was designed to describe the technique of arterial occlusion using a temporary occlusion balloon system as an alternative to coil occlusion during Yttrium-90 radioembolization of hepatic tumors. Methods. Review of charts, angiography, and follow-up imaging studies of consecutive patients undergoing oncological embolization procedures in which a HyperForm system (ev3 Neurovascular, Irvine, CA) was used. Intraprocedural target vessel occlusion and patency of the target vessel on follow-up were recorded. Clinical data and Bremsstrahlung scans were reviewed for evidence of nontarget embolization. Results. Four radioembolization procedures were performed in three patients (all female, age 48-54 (mean 52) years). Five arteries were temporarily occluded (three gastroduodenal arteries, one right gastric artery, and one cystic artery). All radioembolization procedures were successfully completed. Follow-up imaging (either digital subtraction angiography (DSA) or computed tomography angiography (CTA)) was available for all patients between 28-454 (mean 183) days following the procedure, demonstrating all five vessels to be patent. No clinical or imaging evidence for nontarget embolization was found. Conclusions. Temporary balloon occlusion of small and medium-sized arteries during radioembolization allows safe therapy with preserved postprocedural vessel patency on early and midterm follow-up.

  6. Restoration of Failed Renal Graft Function After Successful Angioplasty of Pressure-Resistant Renal Artery Stenosis Using a Cutting Balloon: A Case Report

    SciTech Connect

    Peregrin, J. H.; Buergelova, M.

    2009-05-15

    This study is the report of a 37-year-old male with a transplanted kidney from a 3.5-year-old donor: the graft had two arteries transplanted with an aortic patch to an external iliac artery. Four months after transplantation, the graft function deteriorated, together with the development of hypertension. Stenosis of both graft arteries was detected and the patient was referred for angioplasty. The angiographic result was suboptimal, nevertheless, the graft function improved and was more or less stable (serum creatinine, 160-200 {mu}mol/l) for 4 years, along with persistently difficult-to-control hypertension. Five years after transplantation, the graft function deteriorated again and severe graft artery restenosis was detected. The restenosis did not respond to dilatation, graft function failed, hypertension decompensated, and left ventricular failure developed. The patient required dialysis. A cutting balloon angioplasty opened the artery, and kidney function was restored after a few days: the serum creatinine level dropped to 140-160 {mu}mol/l, and the glomerular filtration rate (creatinine clearance) to 0.65 ml/min/1.73 m{sup 2}. The graft function has now been stable for more than 2 years, however, the hypertension is still difficult to control.

  7. Usefulness of Percutaneous Transluminal Coronary Balloon Angioplasty for the Left Coronary Artery Stenosis 10 Years More Than After Arterial Switch Operation.

    PubMed

    Tsujii, Nobuyuki; Tsuda, Etsuko; Asaumi, Yasuhide; Yamada, Osamu

    2016-04-01

    Proximal stenosis adjacent to the orifice of one or both coronary arteries may occur after the arterial switch operation (ASO) for d-transposition of the great arteries (d-TGA). Coronary artery stenosis (CAS) often progresses within the first 6 months postoperatively and may result in myocardial ischemia and infarction. Although percutaneous transluminal coronary balloon angioplasty (PCBA) for CAS within 15 months after ASO for d-TGA has been reported, there is no report of PCBA for CAS in the late period after ASO. We present the results of PCBA for CAS of the left coronary artery performed more than 10 years after ASO in an 11-year-old boy and a 14-year-old boy without complication. The stenosis degree improved in both patients from 81 to 45 and 80 to 54 %, respectively. Restenosis did not occur, and the stenosis degree improved to about 25 % late after PCBA. Although the initial effect of PCBA may not be dramatic, it can improve late after PCBA. It was considered that the optimal balloon-reference vessel ratio was about 1.0, to obtain the minimal effective lumen diameter. PCBA for CAS even if performed many years after ASO is feasible without complication. PCBA can also provide delayed improvement late after the procedure.

  8. Unintended Thermal Injuries from Radiofrequency Ablation: Organ Protection with an Angioplasty Balloon Catheter in an Animal Model

    PubMed Central

    Knuttinen, Martha-Grace; Van Ha, Thuong G.; Reilly, Christopher; Montag, Anthony; Straus, Christopher

    2014-01-01

    Objectives: The aim of this study was to investigate a novel approach of using a balloon catheter as a protective device to separate liver from the diaphragm or nearby bowel during radiofrequency ablation (RFA) of hepatic dome tumors in an animal model. Materials and Methods: All experimental procedures were approved by animal Institutional Review Board. Using a 3 cm RF needle electrode, 70 hepatic ablation zones were created using ultrasound in 7 pigs. 50 lesions were created using balloon interposition between liver and diaphragm; 20 lesions were created using the balloon device interposed posteriorly between liver and bowel. Additional 21 control lesions were performed. Animals were sacrificed immediately; diaphragm and bowel were then visually inspected and sectioned. Diaphragmatic and bowel injury was then classified according to the depth of thickness. Results: Control lesions caused full thickness injury, either to diaphragm or bowel. During ablation of lesions with balloon interposition, there was significantly less diaphragmatic injury, P < 0.001 and less bowel injury, P < 0.01. Conclusion: Using balloon interposition as a protective device has advantages over previous saline infusion or CO2 insufflation, providing a safe way to expand percutaneous RFA of liver tumors located on the undersurface of the diaphragm. In addition, this method may be used in protection of other organs adjacent to areas being ablated. PMID:24678433

  9. Utilization of laser arterial angioplasty.

    PubMed

    Steg, P G; Ménasché, P

    1989-01-01

    Arterial angioplasty with continuous wave laser radiation is now available in clinical practice and, coupled with balloon catheter angioplasty, has been successful in the treatment of lower limb arterial disease. It appears premature to apply laser angioplasty to coronary artery lesions because of the high incidence of severe complications observed in clinical trials. Experimental studies suggest that some of these complications are related to thermal injury induced by continuous wave laser energy and that they could be minimized by the utilization of pulsed laser sources. Because of recent technologic advances, pulsed laser sources coupled with flexible fiberoptic devices will soon be available for peripheral arterial angioplasty in clinical practice.

  10. Comparison of intravascular optical frequency domain imaging versus intravascular ultrasound during balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension

    PubMed Central

    Kubota, Shuji; Okazaki, Toru; Hara, Hisao; Hiroi, Yukio

    2016-01-01

    Objectives The aims of this study are (1) to evaluate the safety and feasibility of using optical frequency domain imaging (OFDI) during balloon pulmonary angioplasty (BPA) procedures, (2) to assess the correlations between the vessel area (VA) and luminal area (LA) obtained by OFDI and intravascular ultrasound (IVUS), and (3) to compare inter‐ and intra‐observer variability among measurements taken from OFDI and IVUS images. Background The BPA in patients with chronic thromboembolic pulmonary hypertension (CTEPH) is an evolving procedure. Methods Twenty‐three consecutive attempts of pair of OFDI and IVUS during BPA were evaluated. All complications that occurred during‐BPA and up to 48 hr post‐BPA were recorded. Using side branches as landmarks, 48 pairs of regions were chosen to compare measurements of VA and LA. Results OFDI images can be obtained without any procedurally related complications. Although the VA and LA measurements obtained by OFDI were smaller than those obtained by IVUS, high correlations were found (VA: r = 0.78, P < 0.0001 and LA: r = 0.75, P < 0.0001). Less inter‐ and intra‐observer variability was found when using measurements taken from OFDI versus IVUS images. Conclusions OFDI during BPA was safe and feasible. The reproducibility of OFDI imaging was excellent and offered a favorable addition to the BPA procedures. © 2016 The Authors Catheterization and Cardiovascular Interventions Published by Wiley Periodicals, Inc. PMID:26991798

  11. Thermal compression and molding of atherosclerotic vascular tissue with use of radiofrequency energy: implications for radiofrequency balloon angioplasty

    SciTech Connect

    Lee, B.I.; Becker, G.J.; Waller, B.F.; Barry, K.J.; Connolly, R.J.; Kaplan, J.; Shapiro, A.R.; Nardella, P.C.

    1989-04-01

    The combined delivery of pressure and thermal energy may effectively remodel intraluminal atherosclerotic plaque and fuse intimal tears. To test these hypotheses with use of a non-laser thermal energy source, radiofrequency energy was delivered to postmortem human atherosclerotic vessels from a metal hot-tip catheter, block-mounted bipolar electrodes and from a prototype radiofrequency balloon catheter. Sixty-two radiofrequency doses delivered from a metal electrode tip produced dose-dependent ablation of atherosclerotic plaque, ranging from clean and shallow craters with histologic evidence of thermal compression at doses less than 40 J to tissue charring and vaporization at higher (greater than 80 J) doses. Lesion dimensions ranged between 3.14 and 3.79 mm in diameter and 0.20 and 0.47 mm in depth. Tissue perforation was not observed. To test the potential for radiofrequency fusion of intimal tears, 5 atm of pressure and 200 J radiofrequency energy were delivered from block-mounted bipolar electrodes to 48 segments of human atherosclerotic aorta, which had been manually separated into intima-media and media-adventitial layers. Significantly stronger tissue fusion resulted (28.5 +/- 3.3 g) with radiofrequency compared with that with pressure alone (4.8 +/- 0.26 g; p less than 0.0001). A prototype radiofrequency balloon catheter was used to deliver 3 atm of balloon pressure with or without 200 J radiofrequency energy to 20 postmortem human atherosclerotic arterial segments. In 10 of 10 radiofrequency-treated vessels, thermal molding of both normal and atherosclerotic vessel wall segments resulted with increased luminal diameter and histologic evidence of medial myocyte damage.

  12. Restenosis of the coronary stenotic lesions treated by holmium:YAG laser coronary angioplasty

    NASA Astrophysics Data System (ADS)

    Miyazaki, Shunichi; Nonogi, Hiroshi; Goto, Yoichi; Itoh, Akira; Ozono, Keizaburo; Daikoku, Satoshi; Haze, Kazuo

    1994-07-01

    Clinical efficacy of newly developed Holmium YAG laser coronary angioplasty (HLCA) was assessed for 30 patients with angina. There were 12 near left main trunk (LMT) lesions and 4 aorto- ostial lesions. Adjunctive balloon angioplasty was performed for 25 of 30 lesions. Delivered energy ranged from 1.5 to 2.5 watts/pulse and the total exposure time ranged from 6 to 55 seconds. External diameter of laser catheter was 1.5 mm for 13 lesions, 1.4 mm for 17 lesions, and 1.7 mm for 5 lesions. Laser success, defined as 20% reduction of stenotic ratio, was obtained in 21 of 30 (70%) and overall procedural success rate was 93%. There were 3 cases with acute coronary occlusions relieved by adjunctive balloon angioplasty and one coronary perforation without manifestation of cardiac tamponade. There were no large coronary dissection which involved more than 5 mm of the coronary artery. Follow up coronary angiography after 3 months showed restenosis in 14 of 27 patients (52%). Percent stenosis after lasering (56%) was similar to that at 3 months after (62%). HLCA is acutely effective treatment for lesions near LMT, because of low incidence of large coronary dissection. However, angiographical restenosis rate is high at 3 months after HLCA. This may be attributed to the relatively large residual stenosis after the procedure and vessel injury caused by shock wave.

  13. High prevalence of severe coronary artery disease in elderly patients with non-operable chronic thromboembolic pulmonary hypertension referred for balloon pulmonary angioplasty

    PubMed Central

    Wretowski, Dominik; Kostrubiec, Maciej; Dzikowska-Diduch, Olga; Łabyk, Andrzej; Irzyk, Katarzyna; Lichodziejewska, Barbara; Wyzgał, Anna; Jankowski, Krzysztof; Pruszczyk, Piotr

    2016-01-01

    Introduction Balloon pulmonary angioplasty (BPA) is a new emerging catheter-based alternative treatment option for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Aim To show that all elderly CTEPH patients referred for BPA are at higher risk of obstructive coronary artery disease and that, in daily practice, they should undergo invasive coronary angiography. Material and methods Eleven patients at the age of at least 65 years (6 males, 5 females, 77.2 ±5.9 years) with confirmed non-operable type II or type III CTEPH, considered for BPA, underwent elective coronary angiography. Severe obstructive coronary artery disease (CAD) was diagnosed when stenosis of left main coronary artery ≥ 50% or stenosis of ≥ 70% of epicardial arteries was angiographically confirmed. We also screened for CAD consecutive age- and sex-matched 114 PE survivors (52 males, 62 females, 74.8 ±7.2 years) with excluded CTEPH. Results Severe CAD was more frequent in elderly patients with non-operable type II or type III CTEPH candidates for BPA than in elderly acute PE survivors with excluded CTEPH (54.5% vs. 16.7%, p < 0.01), and therefore elderly CTEPH patients referred for BPA were at higher risk of CAD (OR = 5.9, 95% CI: 1.64–21.46, p = 0.007) when compared to elderly survivors after acute PE with excluded CTEPH. Conclusions All elderly CTEPH patients referred for BPA are at higher risk of severe CAD and should routinely undergo invasive coronary angiography before BPA. PMID:27980550

  14. Effect of radiofrequency-generated thermal energy on the mechanical and histologic characteristics of the arterial wall in vivo: implications for radiofrequency angioplasty

    SciTech Connect

    Barry, K.J.; Kaplan, J.; Connolly, R.J.; Nardella, P.; Lee, B.I.; Becker, G.J.; Waller, B.F.; Callow, A.D.

    1989-02-01

    Abrupt reclosure of atherosclerotic vessels after percutaneous transluminal balloon angioplasty has been blamed on traumatic dissections and elastic recoil of the vessel wall. Thermal energy with compression produces fusion of separated arterial wall layers, and heat appears to alter the elastic recoil of the vessel wall. Radiofrequency (RF) thermal energy has been used to perform vascular anastomoses and thermal angioplasty. A simple in vivo experiment was designed to describe and quantitate vascular tissue weld strength produced by a range of RF thermal energy levels. Canine carotid arteries were compressed between a pair of modified bipolar forceps that applied RF energy, causing occlusive tissue welds between the apposed intimal surfaces. The strength of the welds was evaluated by measuring the perfusion pressure required to reopen the vessel lumen. A dosimetry range of 0 to 205 joules showed a typical dose-response curve for the relationship between energy applied and bond strength, plateauing at approximately 300 mm Hg. Light microscopy showed fusion of the inner surfaces of the vessel with preservation of vessel wall architecture. Additionally inflation of a bipolar RF balloon catheter in the normal canine carotid lumen produced an alteration of vessel profile angiographically and histologically. Results of these preliminary experiments suggest that balloon angioplasty with adjunctive RF thermal energy may have benefits in reducing the factors causing acute failure of conventional percutaneous transluminal balloon angioplasty.

  15. Andreas Grüntzig's balloon catheter for angioplasty of peripheral arteries (PTA) is 25 years old.

    PubMed

    Bollinger, A; Schlumpf, M

    1999-02-01

    History of Andreas Grüntzig's time spent in Angiology and Radiology of the Zürich University Hospital (1969-1975). First, the pioneer of catheter therapy discovered that the Achilles tendon reflex is significantly prolonged during claudication pain. Furthermore, he participated actively in the clinical evaluation of Doppler ultrasound. After a stay in the Aggertalklinik (Engelskirchen near Köln, Germany), where he learnt Charles Dotter's original procedure with Eberhard Zeitler, he introduced catheter therapy of peripheral arteries in Zürich. In the same period he developed a new, rigid, sausage-shaped balloon catheter (polyvinylchloride), manufactured the device on his kitchen table together with his wife Michaela, Maria and Walter Schlumpf, and used it first on February 12, 1974 in a patient with intermittent claudication due to subtotal stenosis of the superficial femoral artery. The first successful dilatation of an iliac artery stenosis by his double-lumen catheter, which was modified later on into the famous coronary catheter, followed on January 23, 1975. Soon, the innovative catheter became commercially available (Cook and Schneider Companies). Andreas Grüntzig not only excelled in pioneering novel techniques, but also in patient care, in a prospective follow-up study of his own 242 patients lasting 15 years (results summarized in this article), in the teaching of Swiss scholars like Felix Mahler, Ernst Schneider and Bernhard Meier and many more in the world, and in organizing life demonstrations for large numbers of participants. His career in Cardiology, his work in Atlanta Georgia, USA, and his early tragic death in an airplane accident are briefly mentioned.

  16. Transradial artery coronary angioplasty.

    PubMed

    Kiemeneij, F; Laarman, G J; de Melker, E

    1995-01-01

    This study explored the feasibility and safety of percutaneous coronary balloon angioplasty (PTCA) with miniaturized PTCA equipment via the radial artery. Coronary angioplasty (PTCA) via the femoral or brachial arteries may be associated with rare vascular complications such as bleeding and damage to the artery and adjacent structures. It was postulated that PTCA via the radial artery with miniaturized angioplasty equipment is feasible and that no major puncture site-related complications occur because hemostasis is obtained easily and because no major structures are near the radial artery. With double blood supply to the hand, radial artery occlusion is well tolerated. In 100 patients with collateral blood supply to the right hand, PTCA was attempted with 6F guiding catheters and rapid-exchange balloon catheters for exertional angina (87 patients) or nonexertional angina (13 patients). Angioplasty was attempted in 122 lesions (type A n = 67 [55%], Type B n = 37 [30%], and type C n = 18 [15%]). Pre- and post-PTCA computerized quantitative coronary analysis was performed. Radial artery function and structure were assessed clinically and with Doppler and two-dimensional ultrasound on the day of discharge. Coronary catheterization via the radial artery was successful in 94 patients (94%). The 6 remaining patients had successful PTCA via the femoral artery (n = 5) or the brachial artery (n = 1). Procedural success (120 of 122 lesions) was achieved in 92 patients (98%) via the radial artery and in 98 patients of the total study population.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Laser angioplasty for cardiovascular disease

    NASA Astrophysics Data System (ADS)

    Okada, Masayoshi

    2005-07-01

    Recently, endovascular interventions such as balloon angioplasty, atherectomy and the stenting method, except for conventional surgery have been clinically employed for the patients with atheromatous plaques of the peripheral- and the coronary arteries, because the number of patients with arteriosclerosis is now increasing in the worldwide. Among these procedures, restenoses after endovascular interventions have been remarkably disclosed in 20-40 % of the patients who underwent percutaneous coronary interventions. Thus, there are still some problems in keeping long-term patency by means of endovascular techniques such as balloon angioplasty and atherectomy (1, 2). For reduction of these problems , laser angioplasty using Argon laser was applied experimentally and clinically. Based on excellent experimental studies, laser was employed for 115 patients with stenotic ,or obstructive lesions occluding more thasn 75 % of the peripheral and the coronary arteries angiographycally.

  18. [Coronary angioplasty today].

    PubMed

    Metzger, J P

    1991-10-01

    The rise of coronary angioplasty has been rapid in the last ten years. It is a method of myocardial revascularisation without thoracotomy or cardiopulmonary bypass and is curative in the absence of restenosis. Recent advances concern the development of the material and the pharmacological support which reduce the risk of coronary thrombosis during the procedure. The primary success rate now approaches 90%, that of emergency bypass surgery less than 5%. The use of autoperfusion catheters and the use of intra-aortic balloon pumping improve the safety of the procedure but surgical stand-by remains a necessity in cases of dilatation of proximal main coronary stenosis. Stable and unstable angina are the main indications of a technique particularly appropriate for elderly patients and the treatment of residual post-thrombolytic stenoses, post-radic stenosis or stenosis of a single functional coronary artery. Restenosis is observed in 30 to 40% of cases during the first six months after the dilatation. Its occurrence is not influenced by any of the drugs tested but it could be reduced by the insertion of an endocoronary stent. Abrasive endocoronary techniques and laser angioplasty are alternative methods of treating coronary stenoses inaccessible to conventional balloon angioplasty but they do not reduce the risk of restenosis.

  19. Laser angioplasty and laser-induced thrombolysis in revascularization of anomalous coronary arteries.

    PubMed

    Shah, Rakesh; Martin, Robert E; Topaz, On

    2002-04-01

    Acute coronary syndromes such as unstable angina and myocardial infarction are attributed to a pathophysiologic process that involves rupture of atherosclerotic plaque and subsequent thrombosis. Percutaneous intervention of anomalous coronary arteries in patients who present with acute coronary syndromes impose unique technical challenges related to the specific anatomic course and morphology of these vessels. Selection of appropriate guiding catheter configuration, choice of supportive guidewire, and proper delivery and activation of debulking devices and stents are important steps toward achieving adequate results. Excimer laser angioplasty is a debulking technology for removal of atherosclerotic plaque and associated thrombi. To date, application of laser angioplasty in anomalous coronary arteries is unreported. We herein present clinical data and discuss technical aspects related to performance of excimer laser angioplasty in three symptomatic patients with acute coronary syndrome, two having an anomalous right coronary artery and one with an anomalous circumflex artery. The delivery of laser energy in these cases resulted in rapid thrombolysis of an occlusive thrombus, successful debulking of the underlying atherosclerotic plaque, facilitation of adjunct balloon angioplasty and stenting, and ultimately, improved clinical condition.

  20. Renal Branch Artery Occlusion in a 13-Year-Old Hypertensive Girl: Initial Treatment and Treatment of Recurrent Stenosis by Balloon Angioplasty

    SciTech Connect

    Konez, Orhan; Burrows, Patricia E.; Harmon, William E.

    2001-09-15

    A 13-year-old girl who recently developed hypertension was diagnosed to have an occluded right renal branch artery and was treated successfully with percutaneous transluminal angioplasty (PTA). To our knowledge, PTA has not been reported as a treatment for totally occluded renal branch arteries, and there is no data available regarding the success rate and possible complications.

  1. Relation of left ventricular infarct transmurality and infarct size after primary percutaneous coronary angioplasty to time from symptom onset to balloon inflation.

    PubMed

    Hahn, Joo-Yong; Song, Young Bin; Gwon, Hyeon-Cheol; Choe, Yeon Hyeon; Kim, Jun Hyung; Sung, Jidong; Choi, Seung-Hyuk; Choi, Jin Ho; Kim, Duk Kyung; Hong, Kyung Pyo; Park, Jeong Euy; Lee, Sang Hoon

    2008-11-01

    This study was performed to evaluate the impact of time to reperfusion on infarct size and transmurality after primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). In 73 patients undergoing primary PCI for STEMI, contrast-enhanced magnetic resonance imaging was performed. Infarct size and transmurality on delayed-enhancement imaging were measured. Infarct size was not associated with symptom onset-to-balloon time (23 +/- 9% for <180 minutes, 22 +/- 9% for 180 to 360 minutes, and 24 +/- 11% for >360 minutes, p = 0.62) or door-to-balloon time (23 +/- 8% for <90 minutes, 23 +/- 10% for 90 to 120 minutes, and 22 +/- 11% for >120 minutes, p = 0.88). Infarct transmurality increased significantly with a delay of symptom onset-to-balloon time (73 +/- 22% for <180 minutes, 78 +/- 14% for 180 to 360 minutes, and 86 +/- 14% for >360 minutes, p = 0.04), but not for door-to-balloon time (79 +/- 15% for <90 minutes, 76 +/- 19% for 90 to 120 minutes, and 81 +/- 18% for >120 minutes, p = 0.62). In multivariate analysis, anterior infarction (odds ratio 4.15, 95% confidence interval 1.31 to 13.18, p = 0.02) and myocardial blush grade 0/1 (odds ratio [OR] 3.89, 95% confidence interval [CI] 1.13 to 13.51, p = 0.03) independently predicted a large infarct (infarct size > or =25%). Symptom onset-to-balloon time (OR per 30 minutes 1.26, 95% CI 1.04 to 1.53, p = 0.02) was an independent predictor of transmural infarct (average transmural extent > or =75%) and use of glycoprotein IIb/IIIa inhibitors showed a protective effect (OR 0.09, 95% CI 0.02 to 0.53, p = 0.007). In conclusion, symptom onset-to-balloon time was significantly associated with infarct transmurality but not infarct size in patients undergoing primary PCI for STEMI.

  2. Clinical Outcomes in Diabetic Patients Who Underwent Percutaneous Coronary Intervention during the Plain Old Balloon Angioplasty (POBA)-, Bare Metal Stents (BMS)- and Drug-eluting Stents (DES)-eras from 1984 to 2010

    PubMed Central

    Naito, Ryo; Miyauchi, Katsumi; Konishi, Hirokazu; Tsuboi, Shuta; Ogita, Manabu; Dohi, Tomotaka; Kasai, Takatoshi; Tamura, Hiroshi; Okazaki, Shinya; Isoda, Kikuo; Daida, Hiroyuki

    2017-01-01

    Objective Diabetes is a negative predictor in coronary artery disease patients. Since the introduction of percutaneous coronary intervention (PCI), PCI has evolved through technological advances in devices, improvements in operators' techniques and the establishment of effective therapeutic protocols. The aim of this study is to examine the changes in the clinical outcomes following PCI in patients with diabetes. Methods We compared the clinical outcomes in patients with diabetes following PCI from 1984 to 2010 at Juntendo University over three eras (plain old balloon angioplasty (POBA)-, bare metal stents (BMS)- and drug-eluting stents (DES)-eras). The primary endpoint was a composite of all-cause mortality, non-fatal myocardial infarction, non-fatal stroke and repeat revascularization within 3 years after the index PCI. Results A total of 1,584 patients were examined. The baseline characteristics became unfavorable over time with regard to age, prevalence of hypertension, presentation with acute coronary syndrome and a reduced left ventricular ejection fraction. The administration of aspirin, statins and β-blockers increased over time. The event-free survival rate for the 3-year cardiovascular events was lower in the DES-era. The adjusted relative risk reduction for 3-year cardiovascular events was 46 % in the DES-era compared with the POBA-era. Conclusion The incidence of 3-year cardiovascular events decreased from 1984 to 2010 in patients with diabetes following PCI, despite the higher risk profiles in the DES-era. PMID:28049984

  3. Clinical Outcomes in Diabetic Patients Who Underwent Percutaneous Coronary Intervention during the Plain Old Balloon Angioplasty (POBA)-, Bare Metal Stents (BMS)- and Drug-eluting Stents (DES)-eras from 1984 to 2010.

    PubMed

    Naito, Ryo; Miyauchi, Katsumi; Konishi, Hirokazu; Tsuboi, Shuta; Ogita, Manabu; Dohi, Tomotaka; Kasai, Takatoshi; Tamura, Hiroshi; Okazaki, Shinya; Isoda, Kikuo; Daida, Hiroyuki

    Objective Diabetes is a negative predictor in coronary artery disease patients. Since the introduction of percutaneous coronary intervention (PCI), PCI has evolved through technological advances in devices, improvements in operators' techniques and the establishment of effective therapeutic protocols. The aim of this study is to examine the changes in the clinical outcomes following PCI in patients with diabetes. Methods We compared the clinical outcomes in patients with diabetes following PCI from 1984 to 2010 at Juntendo University over three eras (plain old balloon angioplasty (POBA)-, bare metal stents (BMS)- and drug-eluting stents (DES)-eras). The primary endpoint was a composite of all-cause mortality, non-fatal myocardial infarction, non-fatal stroke and repeat revascularization within 3 years after the index PCI. Results A total of 1,584 patients were examined. The baseline characteristics became unfavorable over time with regard to age, prevalence of hypertension, presentation with acute coronary syndrome and a reduced left ventricular ejection fraction. The administration of aspirin, statins and -blockers increased over time. The event-free survival rate for the 3-year cardiovascular events was lower in the DES-era. The adjusted relative risk reduction for 3-year cardiovascular events was 46 % in the DES-era compared with the POBA-era. Conclusion The incidence of 3-year cardiovascular events decreased from 1984 to 2010 in patients with diabetes following PCI, despite the higher risk profiles in the DES-era.

  4. Balloon Catheter Prevents Contamination

    NASA Technical Reports Server (NTRS)

    Higginson, Gregory A.; Bouffard, Marc R.; Hoehicke, Beth S.; King, Bradley D.; Peterson, Sandra L.

    1994-01-01

    Balloon catheter similar to that used in such medical procedures as angioplasty and heart surgery protects small orifices against contamination and blockage by chips generated in machining operations. Includes small, inflatable balloon at end of thin, flexible tube. Contains additional features adapting it to anticontamination service: balloon larger to fit wider channel it must block; made of polyurethane (rather than latex), which does not fragment if bursts; material made thicker to resist abrasion better; and kink-resistant axial wire helps catheter negotiate tight bends.

  5. Assessment of explanted PTCA balloons.

    PubMed

    Behrend, D; Zinner, G; Sternberg, K; Schroeder, M; Schmitz, K P; Haubold, A

    2000-10-01

    The data presented here are part of a on-going study to define the surface characteristics and properties of explanted PTCA catheters in a further effort to address some of the ramifications of the re-use issue. PTCA balloon catheter were examined after angioplasty in one hundred and sixty-eight patients (n = 168). This series included six balloon types from three manufacturers. The fresh fixed and dehydrated balloons were examined at first with light microscopy and then in a scanning electron microscope. X-ray semiquantitative microanalysis and FT-IR-ATR analysis were also performed on the balloons. Because most blood proteins are water soluble, we examined unfixed balloons with a protein silver staining kit for detection of adhered proteins described by Heukeshoven. A further method for protein detection is the Lowry-analysis. With this method water insoluble proteins can be observed. Our study has shown convincingly that all deployed angioplasty catheters were coated with adherent protein layers. Plaque particles were found embedded in the surfaces of most of the balloons examined. Fissuring and micro tearing of balloon surfaces was noted. FT-IR-ATR analyses of the blood contacted balloon surfaces did not show any peaks indicative of proteins on the balloon surface. The silver staining method also did not show any evidence of protein adsorption on the balloons. On the other hand, the Lowry-analysis yielded clear evidence that water insoluble proteins were adherent to the balloon surfaces. The average measured protein concentration was 17 microg/ml.

  6. High-speed coronary rotational angioplasty with the rotablator

    NASA Astrophysics Data System (ADS)

    Zacca, Nadim M.; Kleiman, Neal S.; Asimacopoulos, P. J.

    1992-08-01

    Percutaneous mechanical rotational ablation with the rotablator can be used effectively as a stand alone treatment for coronary arterial lesions, including those with angiographic morphology considered unfavorable for balloon angioplasty (eccentric, at bends, bifurcating, calcified, ulcerated, completely occluded_, as well as for balloon angioplasty procedure failures. The use of single rather than multiple burrs without balloon assistance, the use of fewer passes and of the nitroglycerine infusion through the rotablator catheter have considerably shortened the time necessary to complete a rotational atherectomy. Further, the apparently infrequent occurrence of post procedure abrupt closure makes this technique attractive in the clinical management of patients with complex coronary artery lesions.

  7. Adjunctive arterial injury and photodynamic therapy with aluminium disulphonated phthalocyanine inhibits intimal hyperplasia

    NASA Astrophysics Data System (ADS)

    Nyamekye, Isaac; McEwan, Jean R.; MacRobert, Alexander J.; Bishop, Christopher C. R.; Bown, Stephen G.

    1994-12-01

    Photodynamic therapy (PDT) of proliferative vascular smooth muscle cells (SMC) reduces intimal hyperplasia (FCIH). We assess the effects of adjunctive balloon injury and immediate PDT on contractile SMC, using aluminum disulphonated phthalocyanine (AlS2Pc) sensitization, on intimal hyperplasia. Groups of 5 Wistar rats underwent tail vein injection with 2.5 mg/kg of aluminum disulphonated phthalocyanine (AlS2Pc). Standard carotid artery balloon injury was performed with a 2FG Fogarty embolectomy catheter and the artery irradiated with 50 J/cm2. Control groups were also studied. Rats were killed at 2 and 4 weeks after treatment and perfusion fixed H&E stained cross-sections assessed by computerized morphometric measurements. Three sections per rat were analyzed. PDT treated arteries were free of FCIH formation in all cases. Laser alone (and to a lesser extent sensitizer alone) produced some reduction in the levels of FCIH compared to untreated but balloon injured vessels. The ratio of the area of intimal hyperplasia in treated vessels to the area of intimal hyperplasia in untreated (balloon only) rats were sensitizer only 98%, laser only 68% and PDT 0% at 4 weeks. PDT given at the time of angioplasty may be affective in the management of restenosis.

  8. Holmium:YAG laser angioplasty: treatment of acute myocardial infarction

    NASA Astrophysics Data System (ADS)

    Topaz, On

    1993-06-01

    We report our clinical experience with a group of 14 patients who presented with acute myocardial infarction. A holmium:YAG laser was applied to the infarct-related artery. This laser emits 250 - 600 mJ per pulse, with a pulse length of 250 microseconds and repetition rate of 5 Hz. Potential benefits of acute thrombolysis by lasers include the absence of systemic lytic state; a shortened thrombus clearing time relative to using thrombolytics; safe removal of the intracoronary thrombus and facilitation of adjunct balloon angioplasty. Potential clinical difficulties include targeting the obstructive clot and plaque, creation of debris and distal emboli and laser-tissue damage. It is conceivable that holmium:YAG laser can be a successful thrombolytic device as its wave length (2.1 microns) coincides with strong water absorption peaks. Since it is common to find an atherosclerotic plaque located under or distal to the thrombotic occlusion, this laser can also be applied for plaque ablation, and the patient presenting with acute myocardial infarction can clearly benefit from the combined function of this laser system.

  9. High-risk coronary angioplasty assisted by active hemoperfusion. A feasibility study.

    PubMed Central

    Angelini, P; Hernandez, C; Ferguson, J J; Leachman, R D; Garcia-Gregory, J A; Benrey, J; Schnee, M J; Fighali, S F; Krajcer, Z

    1996-01-01

    We assessed the effectiveness of distal hemoperfusion support during gradual, prolonged balloon inflation during percutaneous transluminal coronary angioplasty in high-risk patients. The patients were identified as having a poor left ventricular ejection fraction ( < 35%), > 50% of viable myocardium at risk percutaneous coronary balloon angioplasty, or both. A total of 64 procedures were performed in 61 patients. Angiographic success was achieved in 83 of 86 (96.5%) lesions treated with hemoperfusion support. Hospital complications included 1 patient who had a non-Q-wave infarction, 1 who had to undergo redo percutaneous coronary balloon angioplasty, and 5 who required coronary artery bypass operations. The hospital mortality was 7.8% (5 patients). This preliminary study indicates that hemoperfusion support can enable expeditious, simple, economical, and effective percutaneous transluminal coronary balloon angioplasty in a subset of labile patients in whom procedural failure frequently leads to sudden death. PMID:8680269

  10. Histopathology of human laser thermal angioplasty recanalization.

    PubMed

    White, R A; White, G H; Vlasak, J; Fujitani, R; Kopchok, G E

    1988-01-01

    Laserprobe thermal-assisted balloon, angioplasty (LTBA) has demonstrated promising initial clinical results in recanalizing stenotic or occluded superficial femoral and popliteal arteries. Over the past year we have obtained six specimens of laserprobe thermal (LT) and LTBA treated total occlusions (avg. length 12 cm) for histopathologic examination from patients who were treated for limb salvage. Three tissue specimens were obtained acutely, and one was obtained at 6, 8, and 13 days, respectively, after laser angioplasty at the time of revision for complications or failed procedures. Serial histologic sections of the treated LT segments demonstrated recanalization of atherosclerotic lesions to approximately 60-70% of the probe diameter. The LT channels were lined by a thin layer of carbonized or coagulated tissue and several layers of cell necrosis. The histology of the thermal injury was similar regardless of whether it was produced by the heated metal cap or by free argon laser energy. Stellate balloon angioplasty fractures were frequently filled with thrombus. Analysis of these human LT and LTBA specimens revealed that the thermal device produces a confined injury through the path of least resistance. Balloon dilatation produces fragmented cracks in the vessel wall, which appear to be more thrombogenic than the carbonized LT surface. With improved guidance methods, LTBA shows potential for continuing development.

  11. Has multivessel angioplasty displaced surgical revascularization?

    PubMed

    King, S B; Ivanhoe, R J

    1990-01-01

    Over the years, PTCA has been proved a safe and effective therapy for single-vessel CAD. Given the record of favorable results for single-vessel angioplasty, the extension of angioplasty to multivessel CAD soon followed. The successful application of PTCA to multivessel disease has been facilitated by developments in balloon, guidewire, and guide catheter technology. Success rates have been satisfactory, and complications have remained acceptable. Furthermore, as an outgrowth of an understanding of the mechanism and effect of PTCA, guidelines have been developed to aid case selection. As emphasized earlier, these guidelines should weigh heavily in deciding whether to select PTCA as a treatment modality. Presently, in our opinion, PTCA has not yet completely displaced surgery for multivessel CAD. Surgical standby is required for safe PTCA, because emergency surgery can be lifesaving and limit myocardial infarction after failed angioplasty. It is doubtful that surgery will ever relinquish its position as the treatment of choice for left main coronary artery disease. Nor will elective surgery find wide application in single-vessel disease. Whether one mode of revascularization will emerge as the most efficacious for multivessel disease related to long-term survival, limitation of cardiac events, and cost will be addressed in the analysis of the ongoing randomized trials of surgery versus angioplasty. Andreas Gruentzig established that it was possible to work within the coronary artery in an alert and comfortable patient. Interventional cardiology has experienced rapid technologic growth. Many patients formerly treated with bypass surgery can be managed effectively with angioplasty. If effective bail-out methods for acute closure are proven effective and restenosis is limited to a small percentage of patients, angioplasty in some form will further displace CABG. Until those ultimate goals are achieved, the value of angioplasty compared with bypass surgery must rest

  12. Drug-eluting balloons in below the knee treatment.

    PubMed

    VAN DEN Berg, Jos C

    2016-12-01

    The endovascular treatment of atherosclerotic disease of the infra-inguinal arteries has changed significantly since the introduction of drug-eluting balloon technology. The role of angioplasty using drug-eluting balloons for lesions of the superficial femoral and popliteal artery is now well established. The positive results of the use of drug-eluting balloons in the above knee segment could not be achieved in the below-the-knee segment. This paper will give an overview of the current status of drug-eluting balloon angioplasty for below-the-knee lesions, and will present a review of 2 single center registry, 5 randomized trials and a meta-analysis.

  13. Three years of clinical experiences on excimer laser angioplasty

    NASA Astrophysics Data System (ADS)

    Viligiardi, Riccardo; Galiberti, Sandra; Pini, Roberto; Salimbeni, Renzo

    1992-08-01

    Our experience on excimer laser angioplasty in peripheral arteries is reported. During three years 34 patients were treated with improved techniques, following the evolution of the laser and of the delivery systems. Encouraging results in the laser stand alone technique allowed us to reduce the association with balloon dilatation to a limited number of cases.

  14. Predictive factors of restenosis following excimer laser coronary angioplasty

    NASA Astrophysics Data System (ADS)

    Geschwind, Herbert J.; Kvasnicka, Jan; Duport, George; Escojido, Henri; Lablanche, Jean M.

    1993-06-01

    Excimer laser coronary angioplasty has been shown to result in high acute success rate. However, long term follow up has shown significant restenosis. To evaluate the restenosis predictive factors, we analyzed data from patients treated by excimer laser angioplasty in four French clinical centers. A cohort of 166 patients, 140 men and 26 women with mean age of 58 +/- 11 years, was enrolled in the study. Total occlusions, tubular, ostial and calcified lesions, unsuccessful balloon dilatation and/or restenosis were considered as indications for laser angioplasty. Follow-up angiography six months after the procedure was achieved in 80 patients. In conclusion, excimer laser angioplasty is associated with a high initial success rate and an acceptable major complications rate. However the use of this method is limited by significant restenosis rate.

  15. Emergent Treatment of Acute Embolic Superior Mesenteric Ischemia with Combination of Thrombolysis and Angioplasty: Report of Two Cases

    SciTech Connect

    Wakabayashi, H. Shiode, Tsuyoki; Kurose, Michihiro; Moritani, Hiroki; Fujiki, Shigeatsu; Morimoto, Naoki; Kusachi, Shozo

    2004-08-15

    We successfully revascularized the acutely occluded superior mesenteric artery (SMA), caused by a thromboembolus, with a combination of thrombolysis and percutaneous transluminal angioplasty (PTA) in 2 patients. Considerable percent luminal reduction (>90%) was still observed after thrombolysis in both patients. Subsequent adjunctive balloon angioplasty produced sufficient luminal diameter of the SMA (<20% luminal reduction). No serious acute procedural complication occurred. The time from onset to partial reperfusion by thrombolysis was approximately 4.5 and 5.5 hours. Approximately 1 week after the combination therapy, colonoscopy and a small bowel radiocontrast series showed localized mucosal ischemia with mild erosions and ulcerations in the terminal ileum and ascending colon in 1 patient. Subsequent bowel resection was required but the resection was short (<20 cm). The other patient's bowel condition was good and did not require any surgical treatment. The present cases suggest that combination therapy is useful for achieving rapid and sufficient revascularization of acute proximal thromboembolic SMA occlusion, and prevents the considerably broad bowel necrosis that requires surgical bowel resection, resulting in short bowel syndrome.

  16. Spasms of the Hepatic Artery Following Percutaneous Transluminal Angioplasty and Tolazoline Administration in a Liver Transplant Patient

    SciTech Connect

    Propst, Albert; Waldenberger, Peter; Propst, Theresa; Vogel, Wolfgang; Koenigsrainer, Alfred

    1996-05-15

    Vascular complications after liver transplantation include occlusion or stenosis near the sites of anastomosis in the hepatic artery, portal vein, and vena cava. Balloon angioplasty of these stenoses carries little risk and is a useful procedure for the treatment of these problems. Here we describe the case of a liver transplant patient who underwent balloon angioplasty for stenosis of the hepatic artery and who developed spasms of the hepatic artery which were aggravated following intraarterial administration of Tolazoline.

  17. Adjunct Professorships

    ERIC Educational Resources Information Center

    Goldman, Jay P.

    2011-01-01

    Colleges of education have come to rely heavily on superintendents to teach graduate-level classes in educational administration. While no national organization tracks this phenomenon, anecdotal evidence points to widespread and perhaps growing involvement in the adjunct ranks. While the majority reported being assigned to teach semester-long…

  18. Percutaneous transluminal angioplasty: radiological-pathological correlation

    SciTech Connect

    Saffitz, J.E.; Totty, W.G.; McClennan, B.L.; Gilula, L.A.

    1981-12-01

    Radiological and pathological assessment of the degree and extent of arterial injury caused by balloon angioplasty was performed in 20 renal arteries obtained at autopsy. Intact arteries were studied angiographically before and after dilatation and then examined histologically. Both normal and diseased arteries were subjected to varying degrees of dilatation. Damage ranged from minimal inimal disruption to major tears of the muscular media. Equivalent dilatory force created greater damage in the distal (muscular) than in the proximal (elastic) portion of the renal artery. There was no evidence of plaque remodling or compression.

  19. Cutting Balloon: Review on Principles and Background of Use in Peripheral Arteries

    SciTech Connect

    Cejna, Manfred

    2005-05-15

    This review describes peripheral use of cutting balloon (CB) angioplasty (CBA), its characteristics, and its distinction from conventional BA and describes the experimental and clinical background of its current use in peripheral arteries.

  20. [Cardiogenic shock in acute myocardial infarct. Its coronary angioplasty treatment].

    PubMed

    Fernández Valadez, E; García y Otero, J M; Escobar, G P; Frutos Rangel, E; Zúñiga Sedano, J; García García, R; Verduzco Bazavilvazo, S; López Aranda, J; López Ruiz, J

    1993-01-01

    Ventricular dysfunction is the most common cause of in-hospital death in patients with acute myocardial infarction. When cardiogenic shock is manifested the mortality is very high. Seven patients with cardiogenic shock complicating acute myocardial infarction were treated with emergency coronary angioplasty. Four patients required cardiopulmonary resuscitation (CPR), 2 intraaortic balloon pump support and one femoro-femoral bypass pump support during the coronary angioplasty. The angiography success rate was 86%. Two patients died, one in the catheterization laboratory and the other one 24 hours later. The hospital mortality was 29%. Of the patients who survived 4 are in functional class I and one in functional class II (NYHA). Coronary angioplasty therapy in patients with cardiogenic shock complicating acute myocardial infarction plays a decisive role in the reduction of mortality.

  1. Near-IR Fourier transform Raman spectroscopy in surgery and medicine: guidance system for laser angioplasty

    NASA Astrophysics Data System (ADS)

    Nie, Shuming; Ren, Qiushi; Redd, Douglas C. B.; Yu, Nai-Teng

    1992-08-01

    We have recently demonstrated the efficacy of a near-infrared-Raman fiberoptic sensor for use in laser angioplasty and cardiovascular surgery. A major advantage of the Raman-based system over existing guidance techniques is its fingerprinting capability with improved specificity for detecting atherosclerotic tissues both in-vitro and in-vivo. The use of such a fiberoptic sensor will improve the safety of laser angioplasty by eliminating the current risk of vessel wall perforation. Once developed, the device also will be well suited for in-vivo monitoring and characterization of restenosis after balloon angioplasty and in-vivo study of atheroma progression and regression in animal models.

  2. Interventional cardiovascular therapy by laser and thermal angioplasty

    SciTech Connect

    Litvack, F.; Grundfest, W.S.; Segalowitz, J.; Papaioanniou, T.; Goldenberg, T.; Laudenslager, J.; Hestrin, L.; Forrester, J.S.; Eigler, N.A.; Cook, S. )

    1990-03-01

    The advent of balloon angioplasty as a clinical device crystallized the concept of nonsurgical revascularization. The problems of restenosis, diffuse disease, and total occlusions persist despite the demonstrated efficacy of balloon angioplasty. During the past 5 years, a variety of laser devices and catheter designs have demonstrated usefulness in the treatment of peripheral vascular disease. Initial success rates of 70-90% have been reported in occluded femoropopliteal arteries. Further clinical trials are warranted to compare the relative efficacy of these devices with each other and conventional therapies. Thermal ablative devices have not yet shown great promise for treatment of coronary disease. Modified versions of these devices as well as nonthermally acting excimer lasers are promising as clinical tools for enhancing our ability to nonsurgically revascularize patients, and trials with these devices are now underway. 31 references.

  3. Evaluation of a Dedicated Balloon Catheter for Infrapopliteal Difficult Calcified Lesions in Diabetic Patients With Critical Limb Ischemia

    SciTech Connect

    Lupattelli, Tommaso

    2011-02-15

    The purpose of this study was to assess the technical performance and immediate procedural outcome of a new balloon catheter in the treatment of calcified lesions in infrapopliteal arterial disease. Sixty-one patients (81 vessels) with infrapopliteal arterial disease were evaluated. Seventy-four of the 81 treated vessels had total occlusions. The ReeKross 18 peripheral transluminal angioplasty catheter (ClearStream, Wexford, Ireland) is an 0.018-inch guidewire system with 4F sheath compatibility and a rigid shaft intended for enhanced pushability. Only technical procedural outcomes were recorded. In 37 of 61 patients (50 infrapopliteal severely stenosed or occluded vessels), an attempt with a standard balloon was made before the ReeKross 18 was used. In 24 patients, the ReeKross 18 was used as the primary catheter in 23 cases involving crural arteries and in 8 cases involving the foot. The ReeKross 18 crossed the lesion in 55 of 59 (93.2%) patients and 72 of 77 (94.5%) vessels, respectively. Postdilatation results for the 51 patients (64 target lesions) in whom ReeKross 18 balloon dilation was achieved showed <30% residual stenosis in all but 4 patients (5 lesions). Of the patients treated with the ReeKross 18 as the primary catheter, the technical success rate (no adjunctive treatment/stent) was obtained in 20 of 24 (83.3%) patients (27 of 31 [87.1%] target lesions). In the treatment of difficult calcified lesions, the choice of a high-pushability angioplasty catheter, such as the ReeKross 18, warrants consideration.

  4. Drug-coated balloons for coronary and peripheral interventional procedures.

    PubMed

    Wöhrle, Jochen

    2012-10-01

    Paclitaxel-coated balloon (PCB) angioplasty reduces neointimal proliferation, restenosis, and clinical need for target lesion revascularization (TLR). PCB was superior for coronary restenosis in bare-metal and drug-eluting stents compared with uncoated balloon angioplasty and was noninferior compared with paclitaxel-eluting stents. PCB angioplasty should be considered for treatment of coronary in-stent restenosis. For de novo lesions, PCB plus endothelial progenitor cell capturing stents reduced restenosis and TLR in early reports. Among patients with de novo lesions and diabetes, the combination of PCB plus bare-metal stent revealed similar results in lesions compared with paclitaxel-eluting stents. The early results for PCB in small vessels are also very encouraging. Dual antiplatelet therapy duration may be shorter with PCB angioplasty compared with drug-eluting stents. Nevertheless, the risk for thrombotic vessel occlusion is minimized. Considering peripheral arterial disease, PCB angioplasty for femoropopliteal lesions was superior to uncoated balloon angioplasty. Registries indicate PCB to also be effective in lesions below the knee. Since there is no certain class effect, efficacy and safety have to be demonstrated for different types of PCB for coronary and peripheral interventions.

  5. Excimer laser coronary angioplasty: clinical results and future directions

    NASA Astrophysics Data System (ADS)

    Bittl, John A.

    1993-06-01

    Despite four years of intensive clinical investigation, excimer laser coronary angioplasty has not been accepted by the interventional cardiology community as the intervention of choice for any lesion type. Although the preliminary analysis presented here shows that the new technology shows promise for the treatment of saphenous vein graft lesions, aorto-ostial lesions and other lesions, these lesion types account for only about 5 - 10% of cases currently targeted for angioplasty and can frequently be treated with other interventional methods. Broader use of excimer laser angioplasty requires convincing proof that the new technology has clear superiority over other interventional techniques for a wider range of lesion types. Furthermore, the mechanisms of vessel dissection, perforation and abrupt closure need further clarification. Thus, the major challenges for excimer laser angioplasty include: (1) randomized trials to document the superiority of excimer laser over balloon angioplasty; (2) improved catheter designs, including devices for eccentric lesions and total occlusions; and (3) a better understanding of laser-tissue interactions to reduce the unpredictability of unfavorable angiographic outcome.

  6. Drug-Coated Balloons: Current Outcomes and Future Directions.

    PubMed

    Kondapalli, Ananya; Danek, Barbara A; Khalili, Houman; Jeon-Slaughter, Haekyung; Banerjee, Subhash

    2017-04-01

    Paclitaxel-coated drug-coated balloons have significantly improved short-term and mid-term clinical outcomes in patients with symptomatic femoropopliteal peripheral artery disease. However, long-term results are awaited. Furthermore, the clinical success of drug-coated balloons in the infrapopliteal peripheral arteries has been more modest and overall similar to traditional balloon angioplasty, and remains an area of unmet clinical need. This article provides an overview of the clinical evidence for paclitaxel-coated balloons in the femoropopliteal and infrapopliteal peripheral artery distributions and future directions in this area.

  7. Progress in coronary angioplasty.

    PubMed

    Silverton, P

    1986-10-01

    Angioplasty offers an alternative to bypass grafting for an increasing number of patients with coronary artery disease. Improvements in catheter design and manufacture have been responsible for an enlargement of the indications which now include patients with multiple vessel coronary artery disease and those with acute evolving myocardial infarction. The application of laser technology may assist in the reopening of chronically occluded arteries.

  8. The role of resuscitative endovascular balloon occlusion of the aorta (REBOA) as an adjunct to ACLS in non-traumatic cardiac arrest: A review of key concepts, physiology, current evidence, and future directions.

    PubMed

    Daley, James; Morrison, Jonathan James; Sather, John; Hile, Lisa

    2017-01-12

    Non-traumatic cardiac arrest is a major public health problem that carries an extremely high mortality rate. If we hope to increase the survivability of this condition, it is imperative that alternative methods of treatment are given due consideration. Balloon occlusion of the aorta can be used as a method of circulatory support in the critically ill patient. Intra-aortic balloon pumps have been used to temporize patients in cardiogenic shock for decades. More recently, resuscitative endovascular balloon occlusion of the aorta (REBOA) has been utilized in the patient in hemorrhagic shock or cardiac arrest secondary to trauma. Aortic occlusion in non-traumatic cardiac arrest has the effect of reducing the vascular volume that the generated cardiac output is distributed across. This augments myocardial and cerebral perfusion, increasing the probability of a return to a good quality of life for the patient. This phenomenon has been the subject of numerous animal studies dating back to the early 1980s; however, the human evidence is limited to several small case series. Animal research has demonstrated improvements in cerebral and coronary perfusion pressure during ACLS that lead to statistically significant differences in mortality. Several case series in humans have replicated these findings, suggesting the efficacy of this procedure. The objectives of this review are to: 1) introduce the reader to REBOA 2) review the physiology of NTCA and examine the current limitations of traditional ACLS 3) summarize the literature regarding the efficacy and feasibility of aortic balloon occlusion to support traditional ACLS.

  9. Percutaneous Mural Fenestration and Angioplasty for the Treatment of a Refractory Hemodialysis-Related Venous Stenosis

    SciTech Connect

    Denison, Gregory L. Funaki, Brian

    2006-12-15

    Venous stenoses are the leading cause of dialysis graft and mature dialysis fistula malfunction. We report a simple, inexpensive technique for treating stenoses that are refractory to conventional balloon angioplasty and present a case in which this technique was successfully applied.

  10. Holmium:YAG laser coronary angioplasty: results of a multicenter registry

    NASA Astrophysics Data System (ADS)

    Topaz, On

    1994-07-01

    To date, 1201 symptomatic patients with significant coronary artery disease were treated with the mid IR holmium:YAG (2.1 micron) laser in a multicenter study. Updated results of this study, as presented herein, substantiate the important role of this laser in treatment of lesions not ideal for conventional balloon angioplasty. This device is a safe and effective means of coronary revascularization.

  11. Immediate structural changes of porcine renal arteries after angioplasty: a histological and morphometric study.

    PubMed

    D'Alessandro, Delfo; Neri, Emanuele; Moscato, Stefania; Dolfi, Amelio; Bartolozzi, Carlo; Calderazzi, Andrea; Bianchi, Francesco

    2006-01-01

    The aim of this research was to characterize the immediate alterations induced by angioplasty and to compare the results of the application of two types of balloons. Ten porcine renal arteries were dilated with a compliant balloon, and ten with a non-compliant balloon. After angioplastic treatment arterial specimens were wax embedded for light microscopy. Sections were stained with the orcein-Van Gieson method, orcein, haematoxylin-eosin, and PAS. Image analysis was performed taking into consideration the following parameters: thickness of the entire wall, of the tunica media and of the inner elastic lamina. The major axes of the smooth muscle cells nuclei were also measured. The effects of the two types of balloon resulted in changes consisting in thinning of the entire arterial wall, reduction of the tunica media, distension of reticular fibers, presence of wide spaces between smooth muscle cells, stretching of smooth muscle cells, inner elastic lamina thickening. Both angioplasty devices used can modify the vascular wall. The identification of the tunica media structural damages might be useful in order to estimate the behavior of the vascular wall in the follow-up after angioplasty, because the entity of modifications could be predictive of restenosis that often takes place weeks or months after angioplasty.

  12. A pilot study of coronary angioplasty in outpatients.

    PubMed Central

    Laarman, G J; Kiemeneij, F; van der Wieken, L R; Tijssen, J G; Suwarganda, J S; Slagboom, T

    1994-01-01

    BACKGROUND--Is it safe to discharge patients from hospital on the same day as percutaneous transluminal coronary angioplasty (PTCA)? The hypothesis tested was that careful pre and post angioplasty selection of patients can identify a group that is at very low risk of postprocedural complications and that these patients may be discharged on the day of the procedure. METHODS--63 patients undergoing limited risk coronary angioplasty of 72 lesions were studied. So that patients would be able to walk soon after PTCA miniature equipment (6 French catheters and balloon-on-a-wire devices) was passed percutaneously through the right brachial artery. After coronary angioplasty patients with angiographic evidence of dissection and/or thrombus and with complications were assigned to an inpatient group and those in whom PTCA had achieved a good angiographic result were assigned to an outpatient group. RESULTS--Two patients were excluded because the brachial approach failed, leaving 61 patients (70 lesions). After PTCA 50 patients (82%) with 57 lesions (81%) attempted were assigned to the outpatient group. No cardiac complication occurred in this subset (0%; 95% confidence interval 0 to 7%). Eleven patients (18%), in whom 13 lesions (19%) were attempted, were assigned to the inpatient group. Three of these patients (27%; 95% confidence interval 6 to 61%) had cardiac complications. Two patients needed local surgical repair after catheterisation of the brachial artery; one had a haematoma and one had a false aneurysm. CONCLUSIONS--Coronary angioplasty with miniature equipment passed through the brachial artery was a safe procedure with a high initial success rate. The results of this pilot trial suggest that with careful selection of patients before and after angioplasty PTCA can be performed safely in outpatients. PMID:8068463

  13. Coronary arteriography and angioplasty

    SciTech Connect

    King, S.B.; Douglas, J.S.

    1985-01-01

    This book explores biomedical radiography of the heart. Topics considered include six bench marks in the history of cardiac catheterization; normal coronary anatomy; anomalies of the coronary arteries; pathoanotomy of the coronary arteries and complications; indications, limitations, and risks of coronary arteriography and left ventriculography; catheterization techniques in coronary arteriography and left ventriculography: the Sones technique; catheterization techniques in coronary arteriography and left ventriculography: the Judkins technique; modification of Judkins catheters; catheterization techniques in coronary arteriography and left ventriculography multipurpose technique; new views in coronary arteriography; quantitative evaluation of left ventricular function; complications of coronary arteriography: management during and following the procedure; interpretation of coronary arteriograms and left ventriculograms; prevalence and distribution of disease in patients catheterized for suspected coronary disease at Emory University Hospital; the Cardiac Catheterization Laboratory; selection for surgery or percutaneous transluminal coronary angioplasty; intracoronary thrombolysis; and percutaneous transluminal coronary angioplasty.

  14. Lesion-specific laser catheters for angioplasty

    NASA Astrophysics Data System (ADS)

    Murphy-Chutorian, Douglas

    1992-08-01

    Since no one laser catheter can treat all types of disease, a new family of `lesion-specific' devices was evaluated with a holmium laser source. Three-hundred-thirty-one patients (avg. 60 years) with symptomatic coronary disease were studied. Average lesion length was 1.2 cm. A 1.4, 1.5, 1.7, or 2.0 mm, tapered-tip or non-tapered, multifiber catheter (Eclipse, Palo Alto, Calif.) was advanced over the wire while emitting 250 - 600 mj/pulse at 5 Hz. Mean percent stenosis decreased from 89% to 57% after lasing with a mean of 140 pulses. Complications were infrequent. Overall procedural success was 95%. The conclusion is that specialized laser catheters delivering holmium laser energy are capable of reducing the severity of coronary stenoses including balloon angioplasty failures and bypass graft failures. Follow up studies are in progress to assess long term efficacy.

  15. Angioplasty simulation using ChainMail method

    NASA Astrophysics Data System (ADS)

    Le Fol, Tanguy; Acosta-Tamayo, Oscar; Lucas, Antoine; Haigron, Pascal

    2007-03-01

    Tackling transluminal angioplasty planning, the aim of our work is to bring, in a patient specific way, solutions to clinical problems. This work focuses on realization of simple simulation scenarios taking into account macroscopic behaviors of stenosis. It means simulating geometrical and physical data from the inflation of a balloon while integrating data from tissues analysis and parameters from virtual tool-tissues interactions. In this context, three main behaviors has been identified: soft tissues crush completely under the effect of the balloon, calcified plaques, do not admit any deformation but could move in deformable structures, the blood vessel wall undergoes consequences from compression phenomenon and tries to find its original form. We investigated the use of Chain-Mail which is based on elements linked with the others thanks to geometric constraints. Compared with time consuming methods or low realism ones, Chain-Mail methods provide a good compromise between physical and geometrical approaches. In this study, constraints are defined from pixel density from angio-CT images. The 2D method, proposed in this paper, first initializes the balloon in the blood vessel lumen. Then the balloon inflates and the moving propagation, gives an approximate reaction of tissues. Finally, a minimal energy level is calculated to locally adjust element positions, throughout elastic relaxation stage. Preliminary experimental results obtained on 2D computed tomography (CT) images (100x100 pixels) show that the method is fast enough to handle a great number of linked-element. The simulation is able to verify real-time and realistic interactions, particularly for hard and soft plaques.

  16. Balloons for Science.

    ERIC Educational Resources Information Center

    Lally, Vincent E.

    1982-01-01

    Discusses the nature and use of scientific balloons. Topics addressed include: (1) types of balloons; (2) lifting gases; (3) polyethylene balloons; (4) duration of balloon flight; and (5) use of balloons in scientific research. (JN)

  17. Balloons Revisited

    ERIC Educational Resources Information Center

    Jeskova, Z.; Featonby, D.; Fekova, V.

    2012-01-01

    Whilst everyone is familiar with the process of blowing up a balloon, few of us have gone further to quantify the actual pressures involved at different stages in the inflation process. This paper seeks to describe experiments to fill some of those gaps and examine some of the apparently anomalous behaviour of connected balloons. (Contains 12…

  18. Spontaneous Coronary Dissection: "Live Flash" Optical Coherence Tomography Guided Angioplasty.

    PubMed

    Bento, Angela Pimenta; Fernandes, Renato Gil Dos Santos Pinto; Neves, David Cintra Henriques Silva; Patrício, Lino Manuel Ribeiro; de Aguiar, José Eduardo Chambel

    2016-01-01

    Optical Coherence tomography (OCT) is a light-based imaging modality which shows tremendous potential in the setting of coronary imaging. Spontaneous coronary artery dissection (SCAD) is an infrequent cause of acute coronary syndrome (ACS). The diagnosis of SCAD is made mainly with invasive coronary angiography, although adjunctive imaging modalities such as computed tomography angiography, IVUS, and OCT may increase the diagnostic yield. The authors describe a clinical case of a young woman admitted with the diagnosis of ACS. The ACS was caused by SCAD detected in the coronary angiography and the angioplasty was guided by OCT. OCT use in the setting of SCAD has been already described and the true innovation in this case was this unique use of OCT. The guidance of angioplasty with live and short images was very useful as it allowed clearly identifying the position of the guidewires at any given moment without the use of prohibitive amounts of contrast.

  19. Laser welding of balloon catheters

    NASA Astrophysics Data System (ADS)

    Flanagan, Aidan J.

    2003-03-01

    The balloon catheter is one of the principal instruments of non-invasive vascular surgery. It is used most commonly for angioplasty (and in recent years for delivering stents) at a multitude of different sites in the body from small arteries in the heart to the bilary duct. It is composed of a polymer balloon that is attached to a polymer shaft at two points called the distal and proximal bonds. The diverse utility of balloon catheters means a large range of component sizes and materials are used during production; this leads to a complexity of bonding methods and technology. The proximal and distal bonds have been conventionally made using cyanoacrylate or UV curing glue, however with performance requirements of bond strength, flexibility, profile, and manufacturing costs these bonds are increasingly being made by welding using laser, RF, and Hot Jaw methods. This paper describes laser welding of distal and proximal balloon bonds and details beam delivery, bonding mechanisms, bond shaping, laser types, and wavelength choice.

  20. Laser angioplasty of totally occluded arteries of the limb

    NASA Astrophysics Data System (ADS)

    Szopinski, Piotr; Hara, Marek; Noszczyk, Wojciech

    1996-03-01

    The authors summarize their experience in the use of Nd-YAG laser in chronic occlusion of lower limb arteries. Percutaneous transluminal laser angioplasty (PTLA) with laser-heated metal and sapphire tips were used as an adjuvant to conventional balloon angioplasty. In cases of reocclusions, endovascular stents were implanted. Laser recanalization was performed in 46 arteries (iliac, superficial femoral, and popliteal). Indications for the procedure were: limb salvage, claudication below 100 m, and temporal or rest pain. Initial clinical and hemodynamic improvement was observed in 37 (80%) patients. Four perforations occurred without clinical sequel. The one-year cumulative clinical patency was 27 (58%) of the 46 lesions. PTLA may be appropriate for high-risk patients, who are unsuitable for surgical reconstruction because of the concomitant diseases. The combination of laser recanalization and implantation of vascular stents may be a promising method in the management of limb ischemia.

  1. Detection of inflating balloon in optical coherence tomography images of a porcine artery in a beating heart experiment

    NASA Astrophysics Data System (ADS)

    Azarnoush, Hamed; Vergnole, Sébastien; Hewko, Mark; Boulet, Benoit; Sowa, Mike; Lamouche, Guy

    2011-03-01

    Suboptimal results of angioplasty procedures have been correlated to arterial damage during balloon inflation. We propose to monitor balloon inflation during the angioplasty procedure by detecting the balloon contours with intravascular optical coherence tomography (IVOCT). This will shed more light on the interaction between the balloon and the artery and to assess the artery's mechanical response. An automatic edge detection algorithm is applied for detection of the outer surface of an inflating balloon in a porcine artery in a beating heart experiment. A compliant balloon is inflated to deform the artery. IVOCT monitoring of balloon inflation is performed at a rate of 30 frames per second. During inflation, the balloon engages the arterial wall. Therefore, the characterization of the diameter of the inflated balloon leads to a characterization of the luminal diameter of the vessel. This provides precise information about the artery response to a simulated angioplasty procedure, information currently not provided by any other existing technique. In the current experiment, balloon inflation characterization is based on 356 IVOCT frames during which the estimated balloon diameter increases approximately from 1.8 mm to 2.9 mm.

  2. Instability of Reference Diameter in the Evaluation of Stenosis After Coronary Angioplasty: Percent Diameter Stenosis Overestimates Dilative Effects Due to Reference Diameter Reduction

    SciTech Connect

    Hirami, Ryouichi; Iwasaki, Kohichiro; Kusachi, Shozo; Murakami, Takashi; Hina, Kazuyoshi; Matano, Shigeru; Murakami, Masaaki; Kita, Toshimasa; Sakakibara, Noburu; Tsuji, Takao

    2000-03-15

    Purpose: To examine changes in the reference segment luminal diameter after coronary angioplasty.Methods: Sixty-one patients with stable angina pectoris or old myocardial infarction were examined. Coronary angiograms were recorded before coronary angioplasty (pre-angioplasty) and immediately after (post-angioplasty), as well as 3 months after. Artery diameters were measured on cine-film using quantitative coronary angiographic analysis.Results: The diameters of the proximal segment not involved in the balloon inflation and segments in the other artery did not change significantly after angioplasty, but the reference segment diameter significantly decreased (4.7%). More than 10% luminal reduction was observed in seven patients (11%) and more than 5% reduction was observed in 25 patients (41%). More than 5% underestimation of the stenosis was observed in 22 patients (36%) when the post-angioplasty reference diameter was used as the reference diameter, compared with when the pre-angioplasty measurement was used and more than 10% underestimation was observed in five patients (8%).Conclusion: This study indicated that evaluation by percent diameter stenosis, with the reference diameter from immediately after angioplasty, overestimates the dilative effects of coronary angioplasty, and that it is thus better to evaluate the efficacy of angioplasty using the absolute diameter in addition to percent luminal stenosis.

  3. Use of Reactor-Produced Radioisotopes for Prevention Restenosis After Angioplasty

    SciTech Connect

    Knapp, F.F.; Pipes, D.W.

    1999-12-21

    Coronary heart disease leads to myocardial infarction and is a major cause of death in the US. Myocardial infarctions result from atherosclerotic plaque deposits in the coronary arteries, reducing blood flow through these arteries which supply oxygen and nutrients to the heart muscle. The two major approaches for restoring adequate blood flow are coronary bypass graft surgery and coronary angioplasty. Angioplasty is a routinely used clinical procedure, where a deflated balloon attached to the end of a long catheter is inserted into an artery in the leg and then advanced through the aorta into the blocked regions of the coronary arteries. After positioning in the occluded region of the artery, the balloon is inflated with a pressurized saline solution which opens the artery restoring blood flow by pressing the atherosclerotic plaque into the vessel wall. Angioplasty is a widely performed procedure with the coronary arteries and is a much less expensive alternative to coronary bypass surgery. The best patients for angioplasty are those with single occlusions and this method is preferred over bypass grafting because of the significantly reduced expense. The reformation of plaque deposits in arteries (restenosis) following angioplasty, however, is a major clinical problem encountered in as high as 40 percent of patients. Because reduction of health care costs is a major national priority, development of effective new preventative methods for restenoses is an important national priority.

  4. Ballooning Interest.

    ERIC Educational Resources Information Center

    Mebane, Robert C.; Rector, Bronwyn

    1991-01-01

    Presents activities that utilize balloons to encourage students to explore questions related to scientific concepts. Concepts explored include light, heat, charged ions, polarization, and the sense of smell. (MDH)

  5. Percutaneous Transhepatic Use of a Cutting Balloon in the Treatment of a Benign Common Bile Duct Stricture

    SciTech Connect

    Kakani, Nirmal K.; Puckett, Mark; Cooper, Martin; Watkinson, Anthony

    2006-06-15

    Benign biliary strictures (BBS) are difficult to treat. The majority of them are treated either endoscopically or using percutaneous techniques either with stents or conventional angioplasty balloons. To our knowledge we present the first case of use of a cutting balloon in the treatment of BBS through a percutaneous approach.

  6. Successful Angioplasty of a Superficial Femoral Artery Stenosis Caused by a Suture-Mediated Closure Device

    SciTech Connect

    Gemmete, Joseph J. Dasika, Narasimham; Forauer, Andrew R.; Cho, Kyung; Williams, David M.

    2003-08-15

    We report the successful angioplasty of an acute arterial narrowing after suture-mediated closure (SMC) of a femoral arterial puncture. A 75-year-old woman underwent a cerebral arteriogramvia a right common femoral artery puncture. The arteriotomy site was closed with a SMC device. Four days after placement the patient complained of pain in her right calf after walking. An arteriogram 7 days after SMC showed a severe focal stenosis at the origin of the superficial femoral artery involving the presumed puncture site. The lesion was successfully treated with balloon angioplasty. The patient at 6 months was asymptomatic.

  7. Successful angioplasty of three cases of coronary artery dissections using hydrophilic wires

    PubMed Central

    Menon, Rajeev; Kapadia, Anuj

    2014-01-01

    Three cases of successful angioplasty of high-grade coronary dissections using hydrophilic wires were reported. Our first case had edge dissection after a stent deployed in the left anterior descending artery, after which we found it impossible to track the second stent over the regular wires, and which was successful when we tried with a stiffer hydrophilic wire. The second had spontaneous coronary artery dissections (SCAD), and the third case was a complicated plaque with multiple stenotic and ectatic segments along with dissection and successful angioplasty carried out using the same wires and without additional hardware. These wires also provided adequate support in tracking the required balloons and stents PMID:25489325

  8. [Role of laser angioplasty in the management of peripheral arteriopathies. Report of 79 cases].

    PubMed

    Henry, M; Beron, R; Chastel, A; Voiriot, P

    1990-01-01

    From May 1988 to November 1989, 79 of the 341 patients admitted to our center requiring angioplasty for peripheral artery disease were treated by laser angioplasty (LA) associated with secondary dilatation. Laser angioplasty was performed with and Nd-YAG laser coupled by an optical fiber to 1.8, 2.2 and 3 mm sapphires. The population studied included 64 men and 15 women (mean age: 66 years). Functional outcome before LA was class II in 85% of cases (n = 67) and class III and IV respectively in 10 (13%) and 2 patients. Laser angioplasty was the primary indication in 61 patients (77%) with a femoropopliteal (n = 53), iliac (n = 7) or axillary (n = 1) arterial obstruction. Laser angioplasty was the secondary indication in stenoses which could not be negotiated by a guide or balloon (23%; n = 18). Laser angioplasty led to repermeabilization of arterial occlusions in 82% of cases. The best results were obtained for short occlusions of less than 3 cm (n = 5; 100%) and for femoropopliteal lesions (n = 60; 85%). Stenoses were revascularized in all cases. Complementary dilatation was performed at the same time in all revascularized patients. Forty-seven revascularized patients were followed up 3 to 6 months after LA. Results were good in 36 cases (77%); restenosis occurred in 7 cases (15%); and reocclusion in 4 cases (8%). It was possible to treat all restenoses percutaneously (dilatation: n = 5; extruder: n = 1; stent: n = 1).(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Properties of nylon 12 balloons after thermal and liquid carbon dioxide treatments.

    PubMed

    Ro, Andrew J; Davé, Vipul

    2013-03-01

    Critical design attributes of angioplasty balloons include the following: tear resistance, high burst pressures, controlled compliance, and high fatigue. Balloons must have tear resistance and high burst pressures because a calcified stenosis can be hard and nominal pressures of up to 16 atm can be used to expand the balloon. The inflated balloon diameter must be a function of the inflation pressure, thus compliance is predictable and controlled. Reliable compliance is necessary to prevent damage to vessel walls, which may be caused by over-inflation. Balloons are often inflated multiple times in a clinical setting and they must be highly resistant to fatigue. These design attributes are dependent on the mechanical properties and polymer morphology of the balloon. The effects of residual stresses on shrinkage, crystallite orientation, balloon compliance, and mechanical properties were studied for angioplasty nylon 12 balloons. Residual stresses of these balloons were relieved by oven heat treatment and liquid CO2 exposure. Residual stresses were measured by quantifying shrinkage at 80 °C of excised balloon samples using a dynamic mechanical analyzer. Shrinkage was lower after oven heat treatment and liquid CO2 exposure compared to the as-received balloons, in the axial and radial directions. As-received, oven heat treated, and liquid CO2-exposed balloon samples exhibited similar thermal properties (T(g), T(m), X(t)). Crystallite orientation was not observed in the balloon cylindrical body using X-ray scattering and polarized light microscopy, which may be due to balloon fabrication conditions. Significant differences were not observed between the stress-strain curves, balloon compliance, and average burst pressures of the as-received, oven heat treated, and liquid CO2-exposed balloons.

  10. Percutaneous transluminal coronary angioplasty (PTCA)

    MedlinePlus Videos and Cool Tools

    Percutaneous transluminal coronary angioplasty (PTCA) is a minimally invasive procedure to open up blocked coronary arteries, allowing blood to circulate unobstructed to the heart muscle. The procedure begins with ...

  11. Arterial spasm during renal angioplasty

    SciTech Connect

    Beinart, C.; Sos, T.A.; Saddekni, S.; Weiner, M.A.; Sniderman, K.W.

    1983-10-01

    Spasm of the renal arteries during transluminal angioplasty is a well-documented phenomenon with serious potential sequelae, particularly in young patients with fibromusclar dysplasia. The authors report their experience in 98 cases (105 arteries). Tolazoline, lidocaine, nitrates (or calcium blockers, if available), and heparin should be administered either directly into the renal artery or systemically prior to angioplasty to decrease the incidence and severity of spasm.

  12. Adjunct Faculty Handbook.

    ERIC Educational Resources Information Center

    Thompson, Merle O'Rourke

    This handbook for Northern Virginia Community College (NVCC) adjunct faculty presents a variety of information designed for adjunct lecturers in English. Three short introductory sections focus on general information, helpful hints, and the use of office machines. The body of the handbook contains the following sections: (1) Services, including…

  13. Cosmic Balloons

    ERIC Educational Resources Information Center

    El Abed, Mohamed

    2014-01-01

    A team of French high-school students sent a weather balloon into the upper atmosphere to recreate Viktor Hess's historical experiment that demonstrated the existence of ionizing radiation from the sky--later called cosmic radiation. This discovery earned him the Nobel Prize for Physics in 1936.

  14. Balloon Sculpture

    ERIC Educational Resources Information Center

    Warwick, James F.

    1976-01-01

    For the adventurous teacher and student there is an alternative to the often messy mixing, pouring, casting, cutting, scoring and sanding of plaster of Paris for casting or sculptural projects. Balloon sculpture, devised, designed and shown here by a sculptor/teacher, is an eye appealing sculptural form and holds a strong interest for students.…

  15. Percutaneous transluminal excimer laser angioplasty in total peripheral artery occlusion in man

    SciTech Connect

    Wollenek, G.; Laufer, G.; Grabenwoeger, F.

    1988-01-01

    Laser angioplasty and laser-assisted angioplasty have become a clinical reality. Producing sharply defined borders of the ablated area with minimal adjacent thermal damage, excimer lasers offer several proven and some potential advantages over conventional systems. To evaluate the feasibility of excimer laser angioplasty, we have treated one patient using 308-nm radiation via a bare fiber in direct contact with the total occlusion of a right femoral artery. The lesion was successfully recanalized, thus allowing easy passage of the balloon catheter and subsequent dilatation. This percutaneous laser recanalization of an occluded peripheral artery is one of the first to be done in man using excimer laser radiation, thus demonstrating that the technique is feasible and the system is potentially useful.

  16. Percutaneous laser thermal angioplasty: initial clinical results with a laser probe in total peripheral artery occlusions.

    PubMed

    Cumberland, D C; Sanborn, T A; Tayler, D I; Moore, D J; Welsh, C L; Greenfield, A J; Guben, J K; Ryan, T J

    1986-06-28

    A metal-tipped laser fibre was used during percutaneous angioplasty of femoral/popliteal or iliac artery occlusions in 56 patients. Primary success was achieved in 50 (89%) of these total occlusions, providing a channel for subsequent balloon dilatation. Before the procedure, 18 lesions had been judged untreatable by conventional angioplasty and four of the six failures were in these. Complications directly attributable to the laser probe were one case of vessel perforation and two cases of entry into vessel walls; these had no sequelae. Other acute complications were a distal thrombosis in a non-heparinised patient, requiring local streptokinase treatment, and two reocclusions and one transient peripheral embolic episode in the first 24 hours. The laser probe technique has potential for increasing the proportion of patients suitable for angioplasty.

  17. Photodynamic therapy for the prevention of restenosis after angioplasty

    NASA Astrophysics Data System (ADS)

    Asahara, Takayuki; Usui, Mikio; Amemiya, Takashi; Oike, Yasuhisa; Shiraishi, Hiromori; Miyagi, Manabu; Nakajima, Hitoshi; Kato, Tomitsugu; Naito, Yuichi; Ibukiyama, Chiharu

    1993-06-01

    The purpose of this study was to evaluate whether photodynamic therapy (PDT) can destroy the proliferating smooth muscle cells and therefore suppress the occurrence of restenosis after angioplasty. PDT following administration of hematoporphyrin derivatives (HpD) 24 hours before irradiation was performed on 30 rabbits immediately (0D), 3 days (3D), 1 week (1W) and 2 weeks (2W) after balloon injury. HpD accumulation of each group was investigated simultaneously. Irradiation of 27 J/10 mm2 from an Hg-Xe flash lamp light transmitted through an 800 micrometers quartz fiber with a diffusing tip was used. All rabbits were sacrificed 4 weeks after balloon injury. The results were expressed in terms of intima:media thickness ratio at the site of fiber contact (I/M) and intima:media area ratio of the cross section (IA/MA). Inhibition of intimal thickening evaluated on the basis of the I/M ratio was recognized in the 3D-, 1W-, and 2W-PDT group. The most effective photoradiation was at the 1W-PDT (I/M equals 0.78 +/- 0.67), but in 2W-PDT intimal necrosis resulting in a small amount of thickness was observed with less media necrosis. ThreeD and 0D PDT effects reduced with media necrosis. We conclude that PDT after angioplasty would be an ideal preventional therapy of restenosis.

  18. Arterial healing response after angioplasty and its contributions to restenosis

    NASA Astrophysics Data System (ADS)

    Borst, Cornelius; van Erven, Lieselotte; Velema, Evelyn; Post, Mark J.

    1992-08-01

    Balloon angioplasty of coronary obstructions is limited by a 40% angiographic restenosis rate six months after the intervention. Myointimal hyperplasia is a major contributor to restenosis. In 77 normal rabbits we examined the question whether severe thermal interventional injury to the iliac artery wall would result in less myointimal hyperplasia than severe mechanical injury induced by balloon dilation. Eight weeks after percutaneous injury by electrical spark erosion, the metal laser probe, cw Nd:YAG laser energy through the sapphire contact probe, 90 degree(s)C RF heated balloon dilation, or standard balloon dilation the neointima thickness measured up to 380 micrometers . When thermally and mechanically damaged walls were compared, myointimal hyperplasia was similar. We conclude that in the normal rabbit the arterial wall healing response after any injury is neointima formation which is the vessel wall's expression of the general pattern of wound healing. It is inferred that alternative modes of injury in new recanalization techniques will lead to induced restenosis rates.

  19. Primary Angioplasty for the Treatment of Acute ST-Segment Elevated Myocardial Infarction

    PubMed Central

    2004-01-01

    Executive Summary One of the longest running debates in cardiology is about the best reperfusion therapy for patients with evolving acute myocardial infarction (MI). Percutaneous transluminal coronary angioplasty (ANGIOPLASTY) is a surgical treatment to reopen a blocked coronary artery to restore blood flow. It is a type of percutaneous (through-the-skin) coronary intervention (PCI) also known as balloon angioplasty. When performed on patients with acute myocardial infarction, it is called primary angioplasty. Primary angioplasty is an alternative to thrombolysis, clot-dissolving drug therapy, for patients with acute MI associated with ST-segment elevation (STEMI), a change recorded with an electrocardiogram (ECG) during chest pain. This review of the clinical benefits and policy implications of primary angioplasty was requested by the Ontario Health Technology Advisory Committee and prompted by the recent publication of a randomized controlled trial (RCT) in the New England Journal of Medicine (1) that compared referred primary angioplasty with on-site thrombolysis. The Medical Advisory Secretariat reviewed the literature comparing primary angioplasty with thrombolysis and other therapies (pre-hospital thrombolysis and facilitated angioplasty, the latter approach consisting of thrombolysis followed by primary angioplasty irrespective of response to thrombolysis) for acute STEMI. There have been many RCTs and meta-analyses of these RCTs comparing primary angioplasty with thrombolysis and these were the subject of this analysis. Results showed a statistically significant reduction in mortality, reinfarction, and stroke for patients receiving primary angioplasty. Although the individual trials did not show significant improvements in mortality alone, they did show it for the outcomes of nonfatal reinfarction and stroke, and for an end point combining mortality, reinfarction, and stroke. However, researchers have raised concerns about these studies. A main concern

  20. Angioplasty and stent placement - carotid artery - discharge

    MedlinePlus

    ... angioplasty and stenting - discharge; CAS - discharge; Endarterectomy - carotid artery - discharge; Angioplasty - carotid artery - discharge ... were done to open a narrowed or blocked artery that supplies blood to your brain. Your health ...

  1. Coronary Artery Disease: Angioplasty or Bypass Surgery?

    MedlinePlus

    Coronary artery disease: Angioplasty or bypass surgery? I'm getting a cardiac catheterization. If blockages are found, ... angioplasty or bypass surgery? Answers from Rekha Mankad, M.D. During cardiac catheterization, your doctor will examine ...

  2. Is coronary vein angioplasty necessary to provide cardiac resynchronization in selected patients? A case report.

    PubMed

    Sterliński, Maciej; Sosnowski, Cezary; Zajac, Dariusz; Ruzyłło, Witold; Szwed, Hanna

    2008-09-01

    Cardiac resynchronization therapy (CRT) has become a recommended method for patients with congestive heart failure (CHF) and cardiac dyssynchrony. In some cases, CRT implantation procedure can be complicated because of anatomic and technical reasons. Some reports describe balloon angioplasty of stenotic heart veins as a method to achieve the target vessel. We present a case of a 58-year-old male with permanent atrial fibrillation and CHF who was referred for CRT. During the implantation of the pacemaker, the diaphragmatic obstacle in coronary sinus (CS) has been passed after many attempts using a balloon catheter with no inflation. The aim of the report is to discuss, in short, the real necessity of venous angioplasty in the CS bed during CRT implantation.

  3. Physiological flow simulation in residual human stenoses after coronary angioplasty.

    PubMed

    Banerjee, R K; Back, L H; Back, M R; Cho, Y I

    2000-08-01

    To evaluate the local hemodynamic implications of coronary artery balloon angioplasty, computational fluid dynamics (CFD) was applied in a group of patients previously reported by [Wilson et al. (1988), 77, pp. 873-885] with representative stenosis geometry post-angioplasty and with measured values of coronary flow reserve returning to a normal range (3.6 +/- 0.3). During undisturbed flow in the absence of diagnostic catheter sensors within the lesions, the computed mean pressure drop delta p was only about 1 mmHg at basal flow, and increased moderately to about 8 mmHg for hyperemic flow. Corresponding elevated levels of mean wall shear stress in the midthroat region of the residual stenoses, which are common after angioplasty procedures, increased from about 60 to 290 dynes/cm2 during hyperemia. The computations (Ree approximately equal to 100-400; alpha e = 2.25) indicated that the pulsatile flow field was principally quasi-steady during the cardiac cycle, but there was phase lag in the pressure drop-mean velocity (delta p - u) relation. Time-averaged pressure drop values, delta p, were about 20 percent higher than calculated pressure drop values, delta ps, for steady flow, similar to previous in vitro measurements by Cho et al. (1983). In the throat region, viscous effects were confined to the near-wall region, and entrance effects were evident during the cardiac cycle. Proximal to the lesion, velocity profiles deviated from parabolic shape at lower velocities during the cardiac cycle. The flow field was very complex in the oscillatory separated flow reattachment region in the distal vessel where pressure recovery occurred. These results may also serve as a useful reference against catheter-measured pressure drops and velocity ratios (hemodynamic endpoints) and arteriographic (anatomic) endpoints post-angioplasty. Some comparisons to previous studies of flow through stenoses models are also shown for perspective purposes.

  4. Intravascular optical coherence tomography to characterize tissue deformation during angioplasty: preliminary experiments with artery phantoms

    NASA Astrophysics Data System (ADS)

    Azarnoush, Hamed; Vergnole, Sébastien; Pazos, Valérie; Bisaillon, Charles-Étienne; Boulet, Benoit; Lamouche, Guy

    2012-09-01

    We explored the potential of intravascular optical coherence tomography (IVOCT) to assess deformation during angioplasty balloon inflation. Using a semi-compliant balloon and artery phantoms, we considered two experimental scenarios. The goal for the first scenario was to investigate if variation in the elasticity of the structure surrounding the balloon could be sensed by IVOCT monitoring. In this scenario, we used three single-layer phantoms with various mechanical properties. Image analysis was performed to extract the inner and outer diameters of the phantoms at various pressures. The goal for the second scenario was twofold. First, we investigated the IVOCT capability to monitor a more complex balloon inflation process. The balloon was in a folded state prior to inflation. This allowed studying two stages of deformation: during balloon unfolding and during balloon expansion. Second, we investigated IVOCT capability to monitor the deformation in a three-layer phantom used to better mimic a true artery. So, not only were the IVOCT images processed to provide the inner and outer diameters of the phantom, but the layer thicknesses were also determined. In both scenarios, IVOCT monitoring revealed to be very efficient in providing relevant information about the phantom deformation during balloon inflation.

  5. [The practical clinical guidelines of the Sociedad Española de Cardiología on interventional cardiology: coronary angioplasty and other technics].

    PubMed

    Esplugas, E; Alfonso, F; Alonso, J J; Asín, E; Elizaga, J; Iñiguez, A; Revuelta, J M

    2000-02-01

    Interventional cardiology has had an extraordinary expansion in last years. This clinical guideline is a review of the scientific evidence of the techniques in relation to clinical and anatomic findings. The review includes: 1. Coronary arteriography. 2. Coronary balloon angioplasty. 3. Coronary stents. 4. Other techniques: directional atherectomy, rotational atherectomy, transluminal extraction atherectomy, cutting balloon, laser angioplasty and transmyocardial laser and endovascular radiotherapy. 5. Platelet glycoprotein IIb/IIIa inhibitors. 6. New diagnostic techniques: intravascular ultrasound, coronary angioscopy, Doppler and pressure wire. For the recommendations we have used the classification system: class I, IIa, IIb, III like in the guidelines of the American College of Cardiology and the American Heart Association.

  6. The salvage of graft occlusion in a maintenace hemodialysis patient with tuberous sclerosis by percutaneous transluminal angioplasty using intravascular ultrasound: case report.

    PubMed

    Higuchi, Terumi; Abe, Masanori; Okada, Kazuyoshi; Nakajima, Yoshiko; Ohnishi, Yoshihiko; Hagi, Chihiro; Fukuda, Noboru; Kuno, Tsutomu; Takahashi, Susumu; Saito, Satoshi; Nagura, Yuji; Matsumoto, Koichi

    2004-04-01

    End-stage renal failure due to tuberous sclerosis is rare and there is no previous report of a patient with tuberous sclerosis undergoing long-term hemodialysis for over 18 years. The patency rate for a dialysis prosthetic graft is low, however, our patient's graft survived over 16 years. For thrombotic occlusion of a graft, we performed percutaneous thrombectomy and balloon angioplasty and salvaged graft occlusion. Moreover, this case is the first report in which the interventional procedure (mechanical thrombectomy and balloon angioplasty) could be observed by intravascular ultrasound in addition to angiography.

  7. Segmental arterial mediolysis: angioplasty of bilateral renal artery stenoses with 2-year imaging follow-up.

    PubMed

    Soulen, Michael C; Cohen, Debbie L; Itkin, Maxim; Townsend, Raymond R; Roberts, David A

    2004-07-01

    Segmental arterial mediolysis (SAM) is a rare condition caused by loss of muscular elements in the walls of medium-sized, usually visceral, arteries. This causes dissection, occlusion, aneurysm formation, and rupture. The clinical presentation is usually catastrophic as a result of vascular occlusion or rupture. Herein an unusual case of renovascular hypertension resulting from SAM is reported, which was successfully treated with balloon angioplasty.

  8. Remodelling of the Superior Caval Vein After Angioplasty in an Infant with Superior Caval Vein Syndrome

    SciTech Connect

    Mert, Murat Saltik, Levent; Gunay, Ilhan

    2004-08-15

    An 8-month old girl was presented with superior caval vein syndrome early after cardiac surgery. Angiography showed severe stenosis of the superior caval vein with 50 mmHg pressure gradient. Following balloon angioplasty, the pressure gradient was reduced to 7 mmHg with some residual stenosis of the superior caval vein. When the patient was reevaluated 5 months after the procedure, angiography revealed a normal diameter of the superior caval vein without a pressure gradient.

  9. Endovascular techniques in limb salvage: cutting, cryo, brachy, and drug-eluting balloons.

    PubMed

    Davies, Mark G; Anaya-Ayala, Javier E

    2013-04-01

    The complex pathophysiology response to injury of the lower-extremity arteries has prompted the development of several unique balloon technologies to overcome initial technical failures and short-term intimal hyperplasia. Cryoplasty alters the cellular and mechanical properties of the vessel wall during angioplasty. Cutting balloons incise the wall, preventing elastic recoil and allowing expansion of the lumen at a lower pressure, thus limiting barotrauma. Drug-eluting balloons actively transfer inhibitory compounds to the wall during the initial therapy, while brachytherapy balloons allow for localized delivery of radiation to inhibit the proliferative response seen after angioplasty. These platforms provide unique means to enhance immediate and short-term results and also reduce stent usage in the lower extremity.

  10. Balloons and Science Kit.

    ERIC Educational Resources Information Center

    Balloon Council, Washington, DC.

    This document provides background information on balloons including: (1) the history of balloons; (2) balloon manufacturing; (3) biodegradability; (4) the fate of latex balloons; and (5) the effect of balloons on the rainforest and sea mammals. Also included as part of this instructional kit are four fun experiments that allow students to…

  11. Paclitaxel-coated balloons - Survey of preclinical data.

    PubMed

    Schnorr, B; Kelsch, B; Cremers, B; Clever, Y P; Speck, U; Scheller, B

    2010-10-01

    Restenosis following interventions in the coronary or peripheral arteries develops over weeks to months. In coronary arteries the restenosis rate has been markedly reduced since the advent of drug-eluting stents. Non-stent-based methods for local drug delivery enable restenosis inhibition without the need for stent implantation, does not permanently change the structure of the vessel, are repeatable, and seems to be applicable where drug-eluting stents provide insufficient protection. Preclinical data indicate that short exposure of the vessel wall to a lipophilic inhibitor of cell proliferation is sufficient for preventing restenosis. Initial evidence to this effect emerged from an investigation of paclitaxel embedded in a matrix that enhances the solubility and release of the agent from the balloon coating as well as its transfer to the vessel wall. Further corroborating data from preclinical and clinical studies demonstrating a reduction in late lumen loss and lower restenosis rates led to the market introduction of a variety of paclitaxel-coated angioplasty balloons. The effectiveness of restenosis inhibition is not determined by the active agent alone. Other factors that are crucial for the effectiveness and safety of drug-coated angioplasty balloons are the formulation containing the agent and the coating technique. In this review we first outline the development of paclitaxel-coated balloons to then provide an overview of the preclinical results obtained with different paclitaxel-coated balloons and finally compare these with the outcome in patients. The article concludes with a short outlook on initial results with a zotarolimus-coated angioplasty balloon.

  12. Percutaneous excimer laser coronary angioplasty: development of technology and initial clinical results

    NASA Astrophysics Data System (ADS)

    Tcheng, James E.; Miller, James S.; Songer, Ronald W.; Golobic, Robert A.

    1992-08-01

    The development of laser systems suitable for vascular angioplasty is a multidisciplinary endeavor that includes development of the laser energy source, guidance modality, delivery catheter, and assessment of clinical applicability. In this paper we report on the design criteria of percutaneous coronary catheters and how these have guided development of the Spectranetics excimer laser angioplasty system. The Spectranetics CVX-300TM excimer laser angioplasty system was designed for safe application in the cardiac catheterization laboratory while maximizing system maintenance intervals. Recent improvements in catheter design and construction have been directed at optimizing target lesion acquisition and treatment. Lesion access and alignment have been facilitated through the use of optical fiber bundles with increased flexibility. Ablation efficiency has been improved by a combination of increased active fiber area and optimization of the radial location of the fiber array compared to the original devices. Engineered stiffness profiles have been improved and lubricous coatings incorporated to optimize force transmission and tactile feedback for the clinician. Initial clinical results appear favorable. In particular, excimer laser angioplasty appears to have an advantage in the treatment of complex coronary lesions such as diffuse coronary arterial disease, total occlusions, ostial stenoses, moderately calcified lesions, and vein graft disease. In these settings, improved procedural success rates and a lowered incidence of complications have been observed compared to conventional balloon PTCA angioplasty. Examples of complex coronary lesion cases as well as a summary of the data of the initial clinical results from the multicenter trial are also presented in this paper.

  13. Iatrogenic Iliac Artery Rupture: Emergency Management by Longer Stent-Graft on a Shorter Balloon

    SciTech Connect

    Trehan, Vijay; Nigam, Arima; Ramakrishnan, S.

    2007-02-15

    Rupture of an iliac artery during percutaneous transluminal coronary angioplasty is a rare but potentially devastating complication. We report a case of iatrogenic external iliac artery rupture that was successfully treated by temporary balloon occlusion followed by endovascular stent graft placement in an unusual manner. Limited availability of the hardware necessitated the use of a longer bare stent graft mounted on a relatively shorter balloon.

  14. Endovascular Stenting for Unsuccessful Angioplasty of the Aorta in Aortoarteritis

    SciTech Connect

    Tyagi, Sanjay; Kaul, Upkar A.; Arora, Ramesh

    1999-11-15

    Purpose: The efficacy and safety of endovascular stent implantation to correct dissection or a suboptimal result after percutaneous transluminal angioplasty (PTA) was evaluated in patients suffering from aortic stenosis due to aortoarteritis. Methods: Twelve children and young adults [aged (mean {+-} SD) 18.2 {+-} 8.7 years] underwent stent implantation after PTA of the aorta, seven for obstructive dissection, four for ineffective balloon dilatation, and one for recurrent restenosis. Nine patients underwent implantation of self-expandable stents and three received balloon-expandable Palmaz stents. Results: Stent implantation could be successfully performed in all 12 patients. After stent implantation, the peak systolic pressure gradient decreased from 91 {+-} 33.5 mmHg to 12.4 {+-} 12.5 mmHg (p < 0.001). The diameter of the stenosed segment increased from 4.6 {+-} 0.8 mm to 11.1 {+-} 1.9 mm (p < 0.001). The dissection was completely covered in all seven patients with dissection. Except for epigastric pain with vomiting in one patient, there was no complication. On follow-up, over 12-57 months (mean 26.8 {+-} 10.8 months), 11 patients (91.6%) had marked improvement in their blood pressure. Patients with congestive heart failure and claudication also showed improvement. Repeat catheterization in five patients, between 6-30 months (mean 16.8 {+-} 9.1 months) after stent implantation, showed sustained improvement in four and a fusiform, long segment, intrastent restenosis after 30 months in one child. The stenosis was safely redilated. Conclusion: Endovascular aortic stent implantation is safe and provides good immediate relief in patients with unsatisfactory results after balloon angioplasty. Improvement is sustained in most patients on intermediate-term follow-up.

  15. Balloon Kyphoplasty

    PubMed Central

    2004-01-01

    Executive Summary Objective To review the evidence on the effectiveness and cost-effectiveness of balloon kyphoplasty for the treatment of vertebral compression fractures (VCFs). Clinical Need Vertebral compression fractures are one of the most common types of osteoporotic fractures. They can lead to chronic pain and spinal deformity. They are caused when the vertebral body (the thick block of bone at the front of each vertebra) is too weak to support the loads of activities of daily living. Spinal deformity due to a collapsed vertebral body can substantially affect the quality of life of elderly people, who are especially at risk for osteoporotic fractures due to decreasing bone mass with age. A population-based study across 12 European centres recently found that VCFs have a negative impact on health-related quality of life. Complications associated with VCFs are pulmonary dysfunction, eating disorders, loss of independence, and mental status change due to pain and the use of medications. Osteoporotic VCFs also are associated with a higher rate of death. VCFs affect an estimated 25% of women over age 50 years and 40% of women over age 80 years. Only about 30% of these fractures are diagnosed in clinical practice. A Canadian multicentre osteoporosis study reported on the prevalence of vertebral deformity in Canada in people over 50 years of age. To define the limit of normality, they plotted a normal distribution, including mean and standard deviations (SDs) derived from a reference population without any deformity. They reported a prevalence rate of 23.5% in women and a rate of 21.5% in men, using 3 SDs from the mean as the limit of normality. When they used 4 SDs, the prevalence was 9.3% and 7.3%, respectively. They also found the prevalence of vertebral deformity increased with age. For people older than 80 years of age, the prevalence for women and men was 45% and 36%, respectively, using 3 SDs as the limit of normality. About 85% of VCFs are due to primary

  16. Emerging Stent and Balloon Technologies in the Femoropopliteal Arteries

    PubMed Central

    Pastromas, Georgios; Katsanos, Konstantinos; Krokidis, Miltiadis; Karnabatidis, Dimitrios

    2014-01-01

    Endovascular procedures for the management of the superficial femoral (SFA) and popliteal artery disease are increasingly common. Over the past decade, several stent technologies have been established which may offer new options for improved clinical outcomes. This paper reviews the current evidence for SFA and popliteal artery angioplasty and stenting, with a focus on randomized trials and registries of nitinol self-expanding stents, drug-eluting stents, dug-coated balloons, and covered stent-grafts. We also highlight the limitations of the currently available data and the future routes in peripheral arterial disease (PAD) stent and balloon technology. PMID:24672355

  17. Drug-coated balloons in interventional cardiology.

    PubMed

    Giannini, Francesco; Naim, Charbel; Costopoulos, Charis; Latib, Azeem; Colombo, Antonio

    2013-10-01

    Over the last few years, drug-coated balloon (DCB) therapy has emerged as a promising therapeutic intervention for the management of obstructive cardiovascular disease. The dictum of this novel technology is that effective prevention of restenosis can be achieved by the short-term transfer of antiproliferative drug to local arterial tissue by means of a single prolonged balloon angioplasty dilatation. Its main attraction is that no foreign body is implanted eliminating thus the risk of late inflammatory response to device components without preventing positive remodeling. Here, we discuss the evidence regarding the effectiveness of DCB in different lesion types and clinical settings as well as the types of DCB commercially available or under development.

  18. Endovascular Treatment of Superior Vena Cava Syndrome via Balloon-in-Balloon Catheter Technique with a Palmaz Stent

    PubMed Central

    Almanfi, Abdelkader; Massumi, Mehran; Dougherty, Kathryn G.; Parekh, Dhaval R.; Strickman, Neil E.

    2016-01-01

    Superior vena cava syndrome is a well-known disease entity that carries substantial rates of morbidity and mortality. Although most cases of superior vena cava syndrome are secondary to a malignant process, additional causes (such as mediastinal fibrosis, pacemaker lead implantation, or central venous catheter placement) have been reported. Multiple treatment options include percutaneous transluminal angioplasty, stent implantation, thrombolysis, mechanical thrombectomy, and venous grafting. We present a case of superior vena cava syndrome in a symptomatic 30-year-old woman who obtained complete relief of obstruction and marked symptomatic improvement through venoplasty and stenting, aided by our use of a balloon-in-balloon catheter system. PMID:28100973

  19. Combined use of selective intracoronary thrombolysis and percutaneous transluminal coronary angioplasty for the treatment of coronary obstruction.

    PubMed

    Keltai, M; Kádár, A; Palik, I; Rózsa, Z

    1984-01-01

    The case of a young female patient with inferior infarction is presented. In the fifth hour after the onset of MI coronary angiography revealed complete obstruction of the right coronary artery. This obstruction has been recanalized by selective intracoronary infusion of streptokinase. At the site of occlusion there remained a 90% coronary stenosis, causing anginal attacks. By means of balloon-catheter angioplasty the stenosis was reduced to less than 50%. The coronary angioplasty resulted in an improvement of left ventricular function, physical working capacity and cessation of anginal attacks.

  20. Successful management of grade III coronary perforation after percutaneous angioplasty in a high-risk patient: a case report.

    PubMed

    Coloma Araniya, Ricardo; Beas, Renato; Maticorena-Quevedo, Jesús; Anduaga-Beramendi, Alexander; Pastrana Castillo, Marco Antonio

    2016-03-03

    Coronary perforation is a rare complication in patients undergoing percutaneous coronary angioplasty. The mortality of this complication varies depending on factors related to the patient and the procedure performed, reaching 44% in patients with Ellis type III perforation. We report the case of an 81 year old male with multiple cardiovascular risk factors, who underwent percutaneous angioplasty for unstable angina management. The patient developed grade III coronary perforation in the anterior descending artery, which was successfully managed with balloon inflation to 6 atmospheres for 10 minutes twice in the affected area, with an interval of 5 minutes between each dilatation. The patient improved and was discharged.

  1. Peripheral Applications of Drug-Coated Balloons: Past, Present and Future

    SciTech Connect

    Krokidis, Miltiadis Spiliopoulos, Stavros Katsanos, Konstantinos Sabharwal, Tarun

    2013-04-15

    Drug-coated balloon (DCB) technologies represent the latest and hottest development in the field of endovascular treatment of peripheral arterial disease. Initial experience with paclitaxel-coated balloon use in the femoral artery has demonstrated lower mid-term restenosis and superior mid-term clinical outcomes in terms of improved wound healing and reduced repeat angioplasty rates compared with standard balloon angioplasty. Many companies are presently developing and/or improving DCB catheters and therefore ongoing, technical improvements of the already existing platforms, new drugs, and innovative carriers are expected. The ongoing basic research studies and various multicenter randomized, controlled trials that are currently in progress will offer valuable scientific insights regarding the long-term effectiveness and other crucial issues, such as efficacy in various vascular beds, optimal balloon dosage, and post angioplasty antiplatelet therapy. Future applications of these devices also could include in-stent restenosis, anastomotic stenosis of surgical bypass, and benign stenoses of the central venous system. The authors envision that DCB angioplasty will evolve to a major paradigm shift in the endovascular treatment of occlusive vascular diseases.

  2. The Entrepreneurial Adjunct

    ERIC Educational Resources Information Center

    Hess, John

    2004-01-01

    Increasingly, the higher education community is witnessing what the author calls the "entrepreneurial adjunct phenomenon": a kind of merchandising of the needs, concerns, and activities of faculty with short-term, often part-time, appointments that depend on factors like enrollment, budget, and program changes. These faculty members are called any…

  3. Energy from solar balloons

    SciTech Connect

    Grena, Roberto

    2010-04-15

    Solar balloons are hot air balloons in which the air is heated directly by the sun, by means of a black absorber. The lift force of a tethered solar balloon can be used to produce energy by activating a generator during the ascending motion of the balloon. The hot air is then discharged when the balloon reaches a predefined maximum height. A preliminary study is presented, along with an efficiency estimation and some considerations on possible realistic configurations. (author)

  4. Ultrasonic resonant modes of piezoelectric balloons under internal pressure.

    PubMed

    Denham, Lori Vidal; Rice, David A

    2012-09-01

    Properties of a piezoelectric polymeric angioplasty balloon that may decrease the problems of acute closure and restenosis are evaluated in this study. Polyvinylidene difluoride (PVDF), a piezoelectric and pyroelectric polymer, has sufficient strength to serve as a standard angioplasty balloon as well as functioning as an ultrasonic transmitter and/or receiver. These properties enable potential therapeutic applications using ultrasound such as plaque ablation and sonotherapy as well as vulnerable plaque diagnosis using thermography. This study investigates the resonant structure of the PVDF balloon catheter in the frequency range 5-100 kHz. Vibrations of the piezoelectric balloon are modeled using cylindrical shell theory and compared with the observed modal frequencies of PVDF cylinders with and without internal pressure. Modal frequencies are determined by measuring the near-field pressure response of the PVDF cylinders using a high frequency microphone. A rich nodal structure is observed between 5 and 100 kHz with peak relative amplitudes measured between 42 and 45 kHz. Higher order modes for cylinders with 9 μm and 28 μm wall thickness increase in frequency as the internal pressure is increased. Experimental measurements confirm theoretical models that predict both pressure-dependent and pressure-independent resonant frequencies. Frequencies of pressure-dependent modes are calculated within 2.2% of measured values at high pressure.

  5. Utilization of Adjunct Faculty Members.

    ERIC Educational Resources Information Center

    Thompson, Hugh

    Perspectives on the use of adjunct faculty are provided by the Chancellor of Indiana University at Kokomo. Colleges can call upon adjunct faculty to offer courses that would not ordinarily be offered. Adjunct faculty are important in bringing an amount of productivity and experience to degree programs, since they bring expertise in a given…

  6. Influences on vascular wall smooth muscle cells with novel short-duration thermal angioplasty

    NASA Astrophysics Data System (ADS)

    Kunio, M.; Shimazaki, N.; Arai, T.; Sakurada, M.

    2012-02-01

    We investigated the influences on smooth muscle cells after our novel short-duration thermal angioplasty, Photo-thermo Dynamic Balloon Angioplasty (PTDBA), to reveal the mechanism that can suppress neo-intimal hyperplasia after PTDBA. We obtained the sufficient arterial dilatations by short-duration heating (<=15 s, <70°C) and low dilatation pressure (<0.4 MPa) without arterial injuries in our previous in vivo studies. Smooth muscle cells, which play most important role in chronic treatment effects, were heated during PTDBA and stretch-fixed after PTDBA. The dead cell rate by heating, estimated by Arrhenius equation with A=2.5x1016 s-1 and Ea=1.17×105 J mol-1, was 15.7+/-2.2% after PTDBA. The measured deformation rate of smooth muscle cells' nuclei was 1.6+/-0.1 after PTDBA in vivo. We found that the expression of smooth muscle cells' growth factor after PTDBA was inhibited 0.52 fold compared to that after the conventional balloon angioplasty in vivo. The measured neo-intimal hyperplasia occupancy rate was less than 20% after PTDBA in vivo. We prospect that the inhibition of the growth factor's expression by stretch-fixing may result to suppress the neo-intimal hyperplasia. In addition, the decrease of smooth muscle cells' density in the vessel media by heating might be another reason for the neo-intimal hyperplasia suppression.

  7. Short term results of percutaneous transluminal coronary angioplasty with the monorail technique: experience in the first 1000 patients.

    PubMed Central

    de Feyter, P J; Serruys, P W; van den Brand, M; Suryapranata, H; Beatt, K

    1990-01-01

    The monorail technique allows monitoring of all steps of the coronary angioplasty procedure by high quality coronary angiography; easy, rapid, and safe recrossing and redilatation of the lesion if necessary; and stepwise dilatation of a stenosis with sequential increase of size of balloons. Transstenotic pressure differences cannot, however, be measured through the narrow shaft of the standard monorail balloon catheter. The monorail technique was used in 1014 patients (820 men, 194 women; mean age 57.8 years (range 24 to 84]. The indication for coronary angioplasty was stable angina in 52%, unstable angina in 40%, and acute myocardial infarction in 8%. Single vessel coronary angioplasty was attempted in 78%, multilesion coronary angioplasty in 11%, and multivessel coronary angioplasty in 11%. Angiographic success (reduction of stenosis to less than 50% of the luminal diameter) of all attempted lesions was achieved in 93%. The technique was clinically successful--that is, angiographic success of all attempted lesions, no occurrence of a major complication (death, myocardial infarction, acute bypass surgery), and improvement of symptoms--in 92% and partially successful in 1.3%. The clinical success rates were similar for stable angina (91%) and unstable angina (94%), but were somewhat lower for acute myocardial infarction (88%). Failure without major complication occurred in 3.4% of the patients. Failure with a major complication occurred in 3.3% (death 0.3%, myocardial infarction 2.4%, and acute bypass surgery 2.3%). The total major complication rate was higher in unstable angina (4.2%) than in stable angina (3.0%). These results indicate that the monorail technique can be applied safely and effectively for coronary angioplasty of patients with stable angina, unstable angina, and acute myocardial infarction. Images PMID:2337500

  8. Heme oxygenase-1 alleviates cigarette smoke-induced restenosis after vascular angioplasty by attenuating inflammation in rat model.

    PubMed

    Ni, Leng; Wang, Zhanqi; Yang, Genhuan; Li, Tianjia; Liu, Xinnong; Liu, Changwei

    2016-03-14

    Cigarette smoke is not only a profound independent risk factor of atherosclerosis, but also aggravates restenosis after vascular angioplasty. Heme oxygenase-1 (HO-1) is an endogenous antioxidant and cytoprotective enzyme. In this study, we investigated whether HO-1 upregulating by hemin, a potent HO-1 inducer, can protect against cigarette smoke-induced restenosis in rat's carotid arteries after balloon injury. Results showed that cigarette smoke exposure aggravated stenosis of the lumen, promoted infiltration of inflammatory cells, and induced expression of inflammatory cytokines and adhesion molecules after balloon-induced carotid artery injury. HO-1 upregulating by hemin treatment reduced these effects of cigarette smoke, whereas the beneficial effects were abolished in the presence of Zincprotoporphyrin IX, an HO-1 inhibitor. To conclude, hemin has potential therapeutic applications in the restenosis prevention after the smokers' vascular angioplasty.

  9. Drug-Coated Balloons for Infrainguinal Peripheral Artery Disease.

    PubMed

    Sethi, Sanjum S; Lee, Michael S

    2016-07-01

    Revascularization of infrainguinal peripheral artery disease has traditionally been accomplished via percutaneous transluminal angioplasty. However, long-term results have been hampered by high rates of restenosis. Along with the advent of stents, paclitaxel-coated balloons are an emerging therapeutic option for the invasive management of infrainguinal peripheral artery disease. Paclitaxel has been successful in inhibiting neointimal hyperplasia, the main mechanism for in-stent restenosis. Technological advances have facilitated the development of paclitaxel-coated balloons, which show promise in early trials for femoropopliteal stenosis relative to uncoated balloons. For infrapopliteal stenoses, the data remain scant and conflicted. Therefore, large-scale randomized clinical trials with long-term follow-up evaluating safety and effectiveness between various strategies need to be performed to determine the optimal invasive management strategy for infrainguinal peripheral artery disease.

  10. Spontaneous Coronary Dissection: “Live Flash” Optical Coherence Tomography Guided Angioplasty

    PubMed Central

    Bento, Angela Pimenta; Fernandes, Renato Gil dos Santos Pinto; Neves, David Cintra Henriques Silva; Patrício, Lino Manuel Ribeiro; de Aguiar, José Eduardo Chambel

    2016-01-01

    Optical Coherence tomography (OCT) is a light-based imaging modality which shows tremendous potential in the setting of coronary imaging. Spontaneous coronary artery dissection (SCAD) is an infrequent cause of acute coronary syndrome (ACS). The diagnosis of SCAD is made mainly with invasive coronary angiography, although adjunctive imaging modalities such as computed tomography angiography, IVUS, and OCT may increase the diagnostic yield. The authors describe a clinical case of a young woman admitted with the diagnosis of ACS. The ACS was caused by SCAD detected in the coronary angiography and the angioplasty was guided by OCT. OCT use in the setting of SCAD has been already described and the true innovation in this case was this unique use of OCT. The guidance of angioplasty with live and short images was very useful as it allowed clearly identifying the position of the guidewires at any given moment without the use of prohibitive amounts of contrast. PMID:26989520

  11. Angioplasty or Stenting in Adult Coarctation of the Aorta? A Retrospective Single Center Analysis Over a Decade

    SciTech Connect

    Macdonald, Sumaira Thomas, Steven M.; Cleveland, Trevor J.; Gaines, Peter A.

    2003-08-15

    For over 11 years, endovascular treatment by angioplasty (PTA) alone or stenting of adult coarctation at a single center was evaluated. We retrospectively reviewed 28 consecutive patients (31 interventions), median age 25 years, treated between 1991 and 2002, 20 of whom had native coarctation. Thirteen patients had PTA alone (16 procedures) (10 'kissing balloon' angioplasty comprising 12 interventions, and 3 single balloon angioplasty comprising 4 interventions) and 15 patients were stented(15 procedures), including 6 secondary and 9 primary stents. There were no procedural or 30-day complications. For the whole group, the median follow-up was 6.6 years (range 1-10 years). In the PTA group, median follow-up was 9 years (range 3-10) and in the stenting group it was 3 years (range 1-5). There were 9 restenoses in the PTA group (6 after 'kissing balloons' and 3 after single balloon) comprising 56% of the angioplasties (9/16 procedures). There was 1 restenosis in the stenting group diagnosed at computed tomography (CT). The patient was clinically well. For the whole group there were significant reductions in systolic blood pressure (BP) (p 0.0003), diastolic BP (p = 0.004) and number of drugs per patient (p = 0.045) at latest follow-up post-treatment. Five patients discontinued therapy.Analysis of the groups revealed that the reduction of systolic and diastolic BP and number of drugs did not reach statistical significance in the PTA group but were significant in the stent group. The endovascular management of adult coarctation is safe. Stents may be more effective than PTA alone but longer-term follow-up of stents is required.

  12. Drug-coated balloons are replacing the need for nitinol stents in the superficial femoral artery.

    PubMed

    Kitrou, Panagiotis; Karnabatidis, Dimitrios; Katsanos, Konstantinos

    2016-08-01

    Amassed evidence from several randomized controlled trials and high quality meta-analyses clearly support the primary use of paclitaxel-coated balloons (PCB) in the superficial femoral artery over traditional plain balloon angioplasty or primary bare nitinol stenting with significantly lower vascular restenosis, less need for repeat procedures, improved quality of life and potential cost savings for the healthcare system. Stents may be reserved for bail-out in case of a suboptimal dilatation result, and for selected more complex lesions, or in case of critical limb ischemia in order to eliminate vessel recoil and maximize immediate hemodynamic gain. Debulking atherectomy remains unproven, but holds a lot of promise in particular in combination with PCBs, in order to improve compliance of the vessel wall by plaque removal, allow for a better angioplasty result and optimize drug transfer and bioavailability. The present overview summarizes and discusses current evidence about femoropopliteal PCB angioplasty compared to the historical standard of plain old balloon angioplasty and bare nitinol stents. Available evidence is appraised in the context of clinically meaningful results, relevant unresolved issues are highlighted, and future trends are discussed.

  13. Venus Altitude Cycling Balloon

    NASA Astrophysics Data System (ADS)

    de Jong, M. L.

    2015-04-01

    A novel balloon concept is demonstrated that uses mechanical compression as altitude control mechanism to sustain long duration balloon probe flight in the cloud level region of Venus’ atmosphere between 45 and 58 km altitude.

  14. Sinuplasty (Balloon Catheter Dilation)

    MedlinePlus

    ... development of the balloon dilating catheter and its adaptation to sinus surgery. In the 1980s, the field ... used in endoscopic sinus surgery. It is the adaptation or application of minimally-invasive balloon technology to ...

  15. Scientific ballooning in Japan

    NASA Astrophysics Data System (ADS)

    Makino, Fumiyoshi

    Activities in scientific ballooning in Japan during 1998-1999 are reported. The total number of scientific balloons flown in Japan in 1998 and 1999 was sixteen, eight flights in each year. The scientific objectives were observations of high energy cosmic electrons, air samplings at various altitudes, monitoring of atmospheric ozone density, Galactic infrared observations, and test flights of new type balloons. Balloon expeditions were conducted in Antarctica by the National Institute of Polar Research, in Russia, in Canada and in India in collaboration with foreign countries' institutes to investigate cosmic rays, Galactic infrared radiation, and Earth's atmosphere. There were three flights in Antarctica, four flights in Russia, three flights in Canada and two flights in India. Four test balloons were flown for balloon technology, which included pumpkin-type super-pressure balloon and a balloon made with ultra-thin polyethylene film of 3.4 μm thickness.

  16. NASA Balloon Technology Developments

    NASA Technical Reports Server (NTRS)

    Fairbrother, D. A.

    2004-01-01

    The National Aeronautics and Space Administration (NASA) Balloon Program has been, and will continue to be, committed to improving the capabilities of balloons to support science missions. Fundamental to vehicle improvement is a program of technology development that will enable improved flight performance throughout the next decade. The program s technology thrust areas include: materials, vehicle design & development, structural analysis, operations & support systems, performance modeling and planetary balloons. Building on the foundations of the 18-year research and development program, a technology roadmap has been generated which identifies specific areas of interest to NASA and the vision of future developments. The major components of the roadmap are: vehicle systems, balloon-craft systems, operational and safety support systems, and planetary vehicles. Current technology activities include nanocomposite balloon films, a new balloon designed to lift 3600 kgs to 36 km, a balloon rotation rate study and Mars pumpkin balloon investigations. The technology roadmap, as well as specific projects and recent advancements, will be presented.

  17. Transluminal angioplasty for arteriosclerotic disease of the distal vertebral and basilar arteries.

    PubMed Central

    Terada, T; Higashida, R T; Halbach, V V; Dowd, C F; Nakai, E; Yokote, H; Itakura, T; Hieshima, G B

    1996-01-01

    OBJECTIVE: Percutaneous transluminal angioplasty (PTA) for the distal vertebral and basilar artery is now being performed in selected patients with haemodynamically significant lesions of the posterior cerebral circulation. Its effect and overall results were examined. PATIENTS AND METHODS: A balloon dilatation catheter specifically developed for these procedures, with a 2.0-3.5 mm balloon diameter, at 6 atmospheres of pressure, was used. Angioplasty was performed in 12 patients (including six whose initial results have been reported) with angiographically documented stenotic lesions involving either the intracranial vertebral artery (C1-C2 portion) or the basilar artery, and satisfying the following criteria: (1) clinical symptoms suggestive or consistent with a transient ischaemic attack refractory to medical treatment, or small infarction of the posterior circulation; and (2) angiographically documented stenosis greater than 70%. Two of 12 patients had complete thrombosis of the distal vertebral and basilar artery and PTA was performed after successful intra-arterial thrombolysis. RESULTS: Successful results, without complications, were obtained in eight patients, with complete resolution of vertebrobasilar ischaemic symptoms. Immediate complications occurred in four patients including two with vessel dissection, and two with thromboembolism. The two patients with acute arterial dissection were reoperated but developed small infarctions with permanent neurological deficits. The two patients with thromboembolic complication showed transient neurological deficit. The overall stenosis ratio decreased from a mean of 84% pretreatment to 44% after the angioplasty procedure. Restenosis occurred in two patients. Long term clinical follow up in 11 patients who survived more than six months showed resolution of ischaemic symptoms after PTA in all except for one with a restenosis who had recurrent transient ischaemic attacks. CONCLUSION: Transluminal angioplasty may be an

  18. Excimer laser ablation before autoperfusion balloon inflation: a novel therapeutic approach to high grade stenoses in vessels supplying substantial myocardium at risk.

    PubMed

    Krause, P B; Schaer, G L; Parrillo, J E; Klein, L W

    1992-11-01

    The utility of a novel approach employing excimer laser ablation to form a channel for subsequent autoperfusion balloon angioplasty is presented. Two important advantages of this strategy are highlighted: (1) applicability to severe stenoses in vessels supplying substantial myocardium at risk and (2) ability to allow prolonged inflation time to minimize procedure related ischemia and optimize revascularization of the heart. We prospectively selected and studied five patients and performed excimer laser coronary angioplasty using either a 1.3 mm or 1.6 mm laser catheter followed by autoperfusion balloon dilatation. Procedural success was documented by a significant reduction in mean percent diameter stenosis from 89 +/- 4% (S.D.) to 53 +/- 4% after laser angioplasty (p < 0.0001) and subsequently to 20 +/- 4% after autoperfusion balloon angioplasty (p < 0.0001). Clinical success was attained and characterized by resolution of anginal symptoms for at least 4 weeks after hospital discharge. There were no major acute complications encountered; however, restenosis has occurred in 2 out of 5 patients. We therefore recommend this novel pre-dilation strategy with excimer laser followed by autoperfusion balloon angioplasty in selected patients with an extensive amount of myocardium at risk.

  19. The nucleotide analogue 3-deazaadenosine prevents neointima-formation after balloon injury

    SciTech Connect

    Seeger, Florian H.; Hess, Wolfram; Sedding, Daniel; Becker, Gunter; Kinscherf, Ralf; Braun-Dullaeus, Ruediger C.; Viedt, Christiane; Kreuzer, Joerg

    2009-01-23

    We have recently shown that 3-deazaadenosine (c3Ado) inhibits atherogenesis in mice. We studied whether its anti-inflammatory capacity would also affect neointima-formation after balloon injury. Sprague Dawley rats underwent balloon angioplasty. C3Ado was administered orally, starting 5 days prior to the balloon injury and continued for 2 weeks. Fourteen days after balloon injury the intima/media ratio in the c3Ado-treated group was reduced by 67% (p < 0.001) and luminal stenosis by 50% (p < 0.001). Neointimal cellular density was decreased by 25% (p < 0.001) and the induction of c-Jun and ki67 was markedly lower. The reduction of the intima/media ratio was still observed 3 months after balloon injury. Furthermore, a c3Ado-dependent inhibition of PDGF-mediated ERK-activation and proliferation could be demonstrated. Short-term administration of C3Ado inhibits neointima-formation in rats for at least 3 months after injury. The present findings implicate that c3Ado may be useful as an inhibitor of restenosis-formation after balloon angioplasty in humans.

  20. Adjuncts Matter: A Qualitative Study of Adjuncts' Job Satisfaction

    ERIC Educational Resources Information Center

    Rich, Telvis M.

    2016-01-01

    The extrinsic factors that influence the workplace experiences of 27 adjuncts teaching online were explored. In this qualitative research study, the adjuncts' lived experiences were examined through in-depth interviews. The results indicated three emergent factors which influenced the participants' workplace experiences, and the alternative…

  1. NASA balloon technology developments

    NASA Astrophysics Data System (ADS)

    Fairbrother, D. A.

    The National Aeronautics and Space Administration (NASA) Balloon Program has been, and will continue to be, committed to improving the capabilities of balloons to support science missions. Fundamental to vehicle improvement is a program of technology development that will enable improved flight performance throughout the next decade. The program's technology thrust areas include: materials, vehicle design & development, structural analysis, operations & support systems, performance modeling and planetary balloons. Building on the foundations of the 18-year research and development program, a technology roadmap has been generated which identifies specific areas of interest to NASA and the vision of future developments. The major components of the roadmap are: vehicle systems, ballooncraft systems, operational and safety support systems, and planetary vehicles. Current technology activities include nanocomposite balloon films, a new balloon designed to lift 3600 kgs to 36 km, a balloon rotation rate study and Mars pumpkin balloon investigations. The technology roadmap, as well as specific projects and recent advancements, will be presented.

  2. Caught in the Adjunct Trap

    ERIC Educational Resources Information Center

    Hose, Linda; Ford, E. J.

    2014-01-01

    Based on personal experiences garnered through years of adjunct instruction, the authors explore the challenges associated with working in academia without the guarantees of a long-term contract or tenure. Further, adjuncts are desperate to accept any position that is remunerative and this willingness undermines contract negotiation leverage of…

  3. Below-the-ankle Angioplasty and Stenting for Limb Salvage: Anatomical Considerations and Long-term Outcomes

    SciTech Connect

    Katsanos, Konstantinos Diamantopoulos, Athanasios; Spiliopoulos, Stavros; Karnabatidis, Dimitris; Siablis, Dimitris

    2013-08-01

    PurposeTo report the long-term angiographic and clinical results in a series of below-the-ankle (BTA) angioplasty procedures and to present some biomechanical issues related to the unique anatomical geometry of the ankle.MethodsWe performed a retrospective analysis of BTA angioplasty procedures. Clinical end points included technical success, patient mortality, salvage of the treated foot, and repeat target lesion revascularization. Imaging end points included primary patency, binary restenosis of the target lesion at the 50 % threshold, and stent integrity (stent fracture, deformation, or collapse). Univariate subgroup analysis was performed.ResultsIn total, 40 limbs in 37 patients (age 73.5 {+-} 8.2 years) with critical limb ischemia were included and 42 inframalleolar lesions (4.2 {+-} 1.4 cm) were analyzed. Technical success was achieved in 95.2 % (40 of 42). Provisional stent placement was performed in 45.2 % (19 of 42). Two patients died, and two major amputations occurred up to 3 years. At 1 year, overall primary vessel patency was 50.4 {+-} 9.1 %, lesion binary restenosis rate was 64.1 {+-} 8.3 %, and repeat intervention-free survival was 93.6 {+-} 4.3 % according to life table analysis of all treated lesions. Pairwise subgroup analysis showed that BTA self-expanding stents were associated with significantly higher restenosis and poorer primary patency compared to plain balloon angioplasty or sirolimus-eluting balloon-expandable stents. Significant deformation and/or fracture of balloon-expandable stents placed BTA were identified in five of 11. Dynamic imaging showed that the dorsalis pedis artery is kinked during foot dorsiflexion, whereas the distal posterior tibial artery is kinked during plantar flexion of the foot.ConclusionBTA angioplasty for critical limb ischemia treatment is safe and feasible with satisfactory long-term results. BTA stent placement must be reserved for bailout indications.

  4. Angioplasty: MedlinePlus Health Topic

    MedlinePlus

    ... a week of coming home. NIH: National Heart, Lung, and Blood Institute Start Here Angioplasty and Vascular Stenting (Radiological ... Also in Spanish Percutaneous Coronary Intervention (National Heart, Lung, and Blood Institute) What Is a Stent? (National Heart, Lung, ...

  5. Recanalisation of an occluded modified Blalock-Taussig shunt by balloon dilatation.

    PubMed Central

    Sreeram, N; Walsh, K; Peart, I

    1993-01-01

    A four year old boy with pulmonary atresia and ventricular septal defect had an acute cyanotic episode three years after undergoing a right-sided, 6 mm diameter, modified Blalock-Taussig shunt. On admission no continuous murmur could be heard from the shunt and the typical high velocity, continuous flow profile of the shunt could not be identified by Doppler echocardiography. At catheterisation a right subclavian artery angiogram confirmed shunt occlusion. From the subclavian artery, an 0.035 inch wire was used to enter the occluded shunt and then the pulmonary artery. Balloon angioplasty of the entire length of the shunt was performed with 6 mm diameter balloon. After angioplasty the arterial oxygen saturation increased from 63% to 83%. The patient was treated with intravenous heparin followed by warfarin. Repeat catheterisation and angiography eight days later confirmed wide patency of the shunt. Images PMID:8260283

  6. Unmanned powered balloons

    NASA Technical Reports Server (NTRS)

    Korn, A. O.

    1975-01-01

    In the late 1960's several governmental agencies sponsored efforts to develop unmanned, powered balloon systems for scientific experimentation and military operations. Some of the programs resulted in hardware and limited flight tests; others, to date, have not progressed beyond the paper study stage. Balloon system designs, materials, propulsion units and capabilities are briefly described, and critical problem areas are pointed out which require further study in order to achieve operational powered balloon systems capable of long duration flight at high altitudes.

  7. Percutaneous balloon pericardiotomy: a double-balloon technique.

    PubMed

    Iaffaldano, R A; Jones, P; Lewis, B E; Eleftheriades, E G; Johnson, S A; McKiernan, T L

    1995-09-01

    We describe a double-balloon technique for performing a percutaneous balloon pericardiotomy. This technique was employed when the large, single dilation balloon customarily used for this procedure failed to fully inflate across the parietal pericardium. Two smaller balloons were advanced through the same skin tract and simultaneously inflated, thus producing an adequate pericardial window. This double-balloon technique allowed for the more secure anchoring of the balloons across the pericardium and for the delivery of greater dilation pressures.

  8. Advances in balloon endoscopes.

    PubMed

    Araki, Akihiro; Tsuchiya, Kiichiro; Watanabe, Mamoru

    2014-06-01

    In September 2003, a double-balloon endoscope (DBE) composed of balloons attached to a scope and an overtube was released in Japan prior to becoming available in other parts of the world. The DBE was developed by Dr. Yamamoto (1), and 5 different types of scopes with different uses have already been marketed. In April 2007, a single-balloon small intestinal endoscope was released with a balloon attached only to the overtube as a subsequent model. This article presents a detailed account of the development of these scopes up to the present time.

  9. GHOST balloons around Antarctica

    NASA Technical Reports Server (NTRS)

    Stearns, Charles R.

    1988-01-01

    The GHOST balloon position as a function of time data shows that the atmospheric circulation around the Antarctic Continent at the 100 mb and 200 mb levels is complex. The GHOST balloons supposedly follow the horizontal trajectory of the air at the balloon level. The position of GHOST balloon 98Q for a three month period in 1968 is shown. The balloon moved to within 2 deg of the South Pole on 1 October 1968 and then by 9 December 1968 was 35 deg from the South Pole and close to its position on 1 September 1968. The balloon generally moved from west to east but on two occasions moved in the opposite direction for a few days. The latitude of GHOST balloons 98Q and 149Z which was at 200 mb is given. Both balloons tended to get closer to the South Pole in September and October. Other GHOST balloons at the same pressure and time period may not indicate similar behavior.

  10. Kestrel balloon launch system

    SciTech Connect

    Newman, M.J.

    1991-10-01

    Kestrel is a high-altitude, Helium-gas-filled-balloon system used to launch scientific payloads in winds up to 20 knots, from small platforms or ships, anywhere over land or water, with a minimal crew and be able to hold in standby conditions. Its major components consist of two balloons (a tow balloon and a main balloon), the main deployment system, helium measurement system, a parachute recovery unit, and the scientific payload package. The main scope of the launch system was to eliminate the problems of being dependent of launching on long airfield runways, low wind conditions, and long launch preparation time. These objectives were clearly met with Kestrel 3.

  11. Drug eluting balloons for resistant arteriovenous dialysis access stenosis.

    PubMed

    Karnabatidis, Dimitrios; Kitrou, Panagiotis

    2017-03-06

    Vascular access maintenance is vital for hemodialysis patients. Conventional balloon angioplasty is the gold standard of treatment in endovascular therapy according to published guidelines, accompanied by bare metal stents as a bail-out method. Several devices have been used so far with a view to improve patency outcomes, but only covered stents have been proposed as a valid alternative and only for venous juxta-anastomotic stenosis of arteriovenous grafts. Paclitaxel-coated balloons (PCBs) have been extensively investigated in the last few years in pilot studies with small numbers of patients in dialysis access. Results from these studies have been promising so far; however, a larger number of subjects is needed to prove outcomes. Aim of this analysis is to discuss current available studies and explore some critical aspects of PCB use in dialysis access treatment.

  12. Roles of thrombin and platelet membrane glycoprotein IIb/IIIa in platelet-subendothelial deposition after angioplasty in an ex vivo whole artery model

    SciTech Connect

    Kaplan, A.V.; Leung, L.L.; Leung, W.H.; Grant, G.W.; McDougall, I.R.; Fischell, T.A. )

    1991-09-01

    Platelet deposition at the site of injury caused by balloon angioplasty is associated with acute closure and restenosis. In a new ex vivo whole artery angioplasty model, the authors examined the roles of thrombin inhibition with D-Phe-Pro-ArgCH2Cl (PPACK) and inhibition of the platelet membrane fibrinogen receptor glycoprotein IIb/IIIa (GPIIb/IIIa) with monoclonal antibody 7E3 on platelet deposition at the site of balloon injury. Fresh rabbit aortas were mounted in a perfusion chamber. One half of the mounted arterial segment was dilated with a standard angioplasty balloon catheter and the uninjured half served as the control segment. The vessels were perfused with human blood at physiological pressure and shear rates of 180-250 second-1 for 30 minutes. Platelet deposition was measured using 111In-labeled platelets and scanning electron microscopy. With heparin (2 units/ml) anticoagulation, 8.2 {plus minus} 2.2 {times} 10(6) platelets/cm2 were deposited at the site of balloon injury compared with 0.7 {plus minus} 0.2 {times} 10(6) platelets/cm2 on uninjured segments (p less than 0.02, n = 7). PPACK was tested at a concentration (10 microM) that totally inhibited platelet aggregation in response to thrombin. 7E3 was tested at a concentration (10 micrograms/ml) that totally inhibited platelet aggregation. Platelet deposition at the site of balloon injury was reduced 47% by PPACK and 70% by 7E3 compared with heparin. At shear rates seen in nonstenotic coronary arteries, PPACK and 7E3 are more effective than heparin in reducing platelet deposition at the site of balloon injury. The significant inhibition of platelet deposition by PPACK demonstrates the importance of heparin-resistant thrombin in platelet thrombus formation.

  13. Outpatient angioplasty: 4-year experience in one practice.

    PubMed Central

    Payne, S. P.; Stanton, A.; Travers, P.; Glenn, D.; Hanel, K. C.

    1997-01-01

    Angioplasty is often performed as an inpatient procedure after preliminary angiography. In order to increase efficiency and patient comfort we introduced a policy of performing angioplasty for chronic leg ischaemia as an outpatient whenever possible, using duplex scanning to select suitable lesions. This paper examines the safety and feasibility of this policy over a 4-year period. We prospectively assessed 168 consecutive cases which were planned for outpatient angioplasty from a total of 190 cases undergoing angioplasty and found full agreement between duplex scanning and angiography in 92%. Six patients (4%) developed complications of angioplasty requiring admission and another five were admitted for unexpected organisational reasons. Thus, the complication rate of outpatient angioplasty was 4%. All complications were noted at the time of angioplasty with no unexpected readmissions. Angioplasty for leg ischaemia is feasible and safe to perform as an outpatient using duplex scanning to select appropriate cases. PMID:9326123

  14. Cryoplasty Versus Conventional Angioplasty in Femoropopliteal Arterial Recanalization: 3-Year Analysis of Reintervention-Free Survival by Treatment Received

    SciTech Connect

    Diaz, Maria Lourdes; Urtasun, Fermin Barberena, Javier; Aranzadi, Carlos; Guillen-Grima, Francisco; Bilbao, Jose Ignacio

    2011-10-15

    Purpose: To compare long-term efficacy of cryoplasty therapy versus conventional angioplasty in the treatment of peripheral arterial atherosclerotic stenosis on the basis of our 3-year clinical experience. Materials and Methods: From January 2006 to December 2008, a total of 155 patients with 192 lesions of the femoropopliteal sector were randomized to receive either cryoplasty or conventional balloon angioplasty. The primary study end point was lesion target patency. Follow-up with clinical evaluation of patient's symptoms, ankle-brachial index, and Doppler ultrasound was scheduled at 1, 6, 9, 12, 24, and 36 months. Results: For the cryoplasty group (n = 86), technical immediate success was achieved in 74.4% of lesions. Rate of significant dissection was 13.5% and rate of stent placement of 22%. In the long term, target lesion patency rate at 6 months was 59.4%, with rates of 55.9, 52.6, and 49.1% at 1, 2, and 3 years, respectively. For the conventional angioplasty group (n = 69), the immediate technical success rate was 83.7%. Rate of significant dissection was 19%, and rate of stent placement was 72.9%. Patency rates at 6 months and at 1, 2, and 3 years were 71.5, 61.2, 60, and 56%, respectively. Conclusion: Compared with conventional angioplasty, cryoplasty showed good immediate success rates with lower stent placement rates. During the 3-year follow-up, patency rates tended to equalize between the two modalities.

  15. Clinical laser angioplasty with a pulsed neodymium:YAG laser: long-term followup

    NASA Astrophysics Data System (ADS)

    Lawrence, Roy N.; Michaels, Jonathan A.; Cross, Frank W.; Raphael, Michael; Adiseshiah, M.; Marston, A.

    1992-08-01

    Since December 1986, 140 laser angioplasty procedures have been carried out using a pulsed Nd:YAG laser (Lumonics Ltd. Rugby, UK). The laser produces 100 microsecond(s) ec pulses at a wavelength of 1064 nm and a repetition rate of 10 Hz. All procedures were carried out for critical ischaemia or severe claudication in patients who had complete occlusion of the superficial femoral artery (SFA). All occlusions were over 5 cm in length or previous failures of balloon angioplasty and would otherwise have proceeded to bypass surgery. The occlusion was approached percutaneously via the ipsilateral femoral artery and successful recanalization was followed by balloon dilatation. Problems with access were encountered in 18% of the procedures, about half of which were subsequently repeated with successful access. There was failure of recanalization in 26% of the cases, five due to vessel perforation. These did not result in clinical sequelae. Early occlusion (< 24 hours) occurred in nine cases, most being related to severely ischaemic limbs with very poor run-off. Three of these were salvaged with thrombolytic therapy. We have meaningful follow-up of those cases where we were successful. Forty-four patients remain patent, at a mean of 30.4 months post-procedure (range 3 - 47 months). Of the 19 patients who reoccluded, (mean 12.1 months, range 1 - 26 months), seven had bypass grafts, three underwent amputation (all three presented with rest pain), two had repeat laser procedures, and seven were treated conservatively. Thirteen percent of the patients have died, chiefly from cardiovascular disease elsewhere. Overall, continued patency has been achieved in 32% of limbs considered for laser treatment, but this rises to 60% of all initially successful procedures. In conclusion, laser angioplasty may avoid the need for vascular surgery in a significant number of patients.

  16. Mentoring adjunct faculty: innovative solutions.

    PubMed

    Peters, Mary Anne; Boylston, Mary

    2006-01-01

    Rising enrollments in schools of nursing have increased the demand for qualified nursing faculty. In the midst of a nurse faculty shortage, many academic institutions are relying on adjunct faculty to fill the gap. The increasing number of adjunct faculty and their need for orientation to the faculty role presents a challenge to schools and departments of nursing. The authors discuss innovative solutions to these challenges.

  17. Modelling Hot Air Balloons.

    ERIC Educational Resources Information Center

    Brimicombe, M. W.

    1991-01-01

    A macroscopic way of modeling hot air balloons using a Newtonian approach is presented. Misleading examples using a car tire and the concept of hot air rising are discussed. Pressure gradient changes in the atmosphere are used to explain how hot air balloons work. (KR)

  18. The Great Balloon Controversy.

    ERIC Educational Resources Information Center

    Chase, Valerie

    1989-01-01

    Discusses the harmful effects of balloon launches and the dumping of plastic debris into oceans. Cites several examples of plastic materials being discovered inside the bodies of sick and/or dead marine animals. Offers alternative activities to releasing balloons into the atmosphere. (RT)

  19. Balloon film strain measurement

    NASA Astrophysics Data System (ADS)

    Rand, James L.

    In order to understand the state of stress in scientific balloons, a need exists for the measurement of film deformation in flight. The results of a flight test program are reported where material strain was measured for the first time during the inflation, launch, ascent and float of a typical natural shape, zero pressure scientific balloon.

  20. Clefting in pumpkin balloons

    NASA Astrophysics Data System (ADS)

    Baginski, F.; Schur, W.

    NASA's effort to develop a large payload, high altitude, long duration balloon, the Ultra Long Duration Balloon, focuses on a pumpkin shape super-pressure design. It has been observed that a pumpkin balloon may be unable to pressurize into the desired cyclically symmetric equilibrium configuration, settling into a distorted, undesired stable state instead. Hoop stress considerations in the pumpkin design leads to choosing the lowest possible bulge radius, while robust deployment is favored by a large bulge radius. Some qualitative understanding of design aspects on undesired equilibria in pumpkin balloons has been obtained via small-scale balloon testing. Poorly deploying balloons have clefts, but most gores away from the cleft deploy uniformly. In this paper, we present models for pumpkin balloons with clefts. Long term success of the pumpkin balloon for NASA requires a thorough understanding of the phenomenon of multiple stable equilibria and means for quantitative assessment of measures that prevent their occurrence. This paper attempts to determine numerical thresholds of design parameters that distinguish between properly deploying designs and improperly deploying designs by analytically investigating designs in the vicinity of criticality. Design elements which may trigger the onset undesired equilibria and remedial measures that ensure deployment are discussed.

  1. Percutaneous transluminal coronary angioplasty in a patient in cardiogenic shock due to recent anterior wall MI with history of prior inferior wall MI 15 days back.

    PubMed

    Kahali, Dhiman; Mondal, Saroj; Sadhu, Parimal

    2012-05-01

    Extensive damage of the myocardium following an acute myocardial infarction usually causes cardiogenic shock. A 66-year-old male patient was treated successfully by primary percutaneous transluminal coronary angioplasty (PTCA) following an acute anterior wall myocardial infarction with prior moderate LV systolic dysfunction and developing cardiogenic shock with intra-aortic balloon counterpulsation (IABP), ventilator support and support with four inotropic drugs in full dosage.

  2. Combination of 8-methoxypsoralen and ultraviolet A inhibits smooth muscle proliferation in vitro and in vivo after angioplasty

    NASA Astrophysics Data System (ADS)

    March, Keith L.; Spaedy, Tony J.; Aita, Michael; Wilensky, Robert L.; Gradus-Pizlo, Ionina; Hathaway, David R.

    1994-07-01

    Smooth muscle cell proliferation plays a major role in restenosis following angioplasty. We have studied the effects of ultraviolet A (UVA) activation of 8-methoxypsoralen (8-MOP) on cultured SMC as well as atherosclerotic rabbit femoral arteries following angioplasty. 8-MOP and UVA display synergistic proliferation inhibition of cultured SMC in a cell-cycle independent manner. At intermediate doses, a cytostatic effect was seen over a 28 day period following a single exposure. In conclusion, a combination of 8-MOP and UVA significantly lowered SMC proliferation and cellularity in cell culture as well as in the neointima and media after balloon-induced vascular injury in the atherosclerotic rabbit model. This approach of systemic administration and local activation is feasible and offers a potential therapy for restenosis.

  3. Advances in below-the-knee drug-eluting balloons.

    PubMed

    Ferraresi, R; Centola, M; Biondi-Zoccai, G

    2012-04-01

    The management of critical limb ischemia due to below-the-knee disease remains challenging due to the frequent patient comorbidities, diffuse vascular involvement, and high rates of restenosis and disease progression. The BASIL study has established the substantial equivalence between bypass surgery and percutaneous transluminal angioplasty in this setting, at least at mid-term follow-up, but percutaneous techniques and devices have seen major developments since the publication of this pivotal trial in 2005. A major breakthrough has indeed been the introduction of drug-eluting balloons, which have several theoretical advantages in comparison to standard balloons and metallic stents for infra-popliteal lesions. Two clinical trials have already been reported with favorable results for the In.Pact Amphirion paclitaxel-eluting balloon, when employed for below-the-knee lesions. We hereby discuss the rationale for the use of drug-eluting balloons in this complex setting and the main findings of the study by Schmidt et al. and the DEBATE-BTK trial.

  4. Successful Percutaneous Transluminal Angioplasty and Stenting in Acute Mesenteric Ischemia

    SciTech Connect

    Gartenschlaeger, Soeren Bender, Siegfried; Maeurer, Juergen; Schroeder, Ralf J.

    2008-03-15

    Acute mesenteric ischemia (AMI) is a life-threatening emergency. The complications are high by the time of diagnosis in most cases and therefore only few data on primary percutaneous intervention with percutaneous transluminal angioplasty (PTA) and stenting in AMI are available. We present the case of an 84-year-old woman who presented to our emergency department complaining of an acute worsening of pre-existing abdominal periumbilical pain, nausea, vomiting, and diarrhea. She had previously undergone percutaneous transluminal embolectomy for an acute occlusion of the left common femoral artery. Due to suspicion of intestinal infarction, conventional angiography of the aorta and the superior mesenteric artery (SMA) was performed and confirmed a proximal occlusion of the SMA. Percutaneous SMA recanalization with balloon dilation and subsequent stent implantation was carried out successfully. The abdominal symptoms subsided after this procedure. In AMI that is diagnosed early, endovascular stenting should be considered as an alternative treatment to the surgical approach that avoids the need for surgical bowel resection.

  5. Percutaneous laser-assisted thermal coronary angioplasty in native coronary arteries and saphenous vein grafts: initial results and angiographic follow-up.

    PubMed

    Linnemeier, T J; Rothbaum, D A; Cumberland, D C; Landin, R J; Hodes, Z I; Ball, M W

    1990-01-01

    Percutaneous laser-assisted thermal coronary angioplasty was attempted in 29 vessels (27 patients): 10 left anterior descending, 2 left circumflex and 17 mid-shaft (non-anastomotic) saphenous vein grafts. Argon or YAG laser thermal energy was applied via a 1.3, 1.6 or 1.9 mm metal capped probe followed by conventional balloon angioplasty in 27 vessels and sole thermal laser therapy in two vessels. The laser probe successfully crossed 83% (24/29) of vessels and subsequent balloon dilatation increased the success rate to 93% (25/27). Perforation occurred in a vein graft resulting in one in-hospital death post repeat emergency coronary artery bypass graft surgery. Angiographic follow-up was obtained in 85% (24/28) of vessels. Angiographic restenosis ( greater than 50% reduction in lumen diameter) occurred in 27% (3/11) of native coronary arteries and 62% (8/13) of saphenous vein grafts. Therefore, despite high initial success rates, the application of laser thermal energy with small laser probes relative to vessel size, followed by conventional balloon angioplasty, does not appear to alter restenosis. Further evaluation of coronary laser systems should be continued only with catheters that are capable of creating channels closer to the size of the vessel treated.

  6. The laser driven short-term heating balloon catheter: Relation between the chronic neointimal hyperplasia formation and thermal damage to arterial smooth muscle cells.

    PubMed

    Shimazaki, Natsumi; Hayashi, Tomoaki; Kunio, Mie; Igami, Yuka; Arai, Tsunenori; Sakurada, Masami

    2010-01-01

    We proposed a novel laser-driven short-term heating angioplasty to realize restenosis-suppressive angioplasty for peripheral artery disease. In this study, we investigated the chronic intimal hyperplasia formation after the short-term heating dilatation in vivo, as well as the thermal damage calculation on arterial smooth muscle cells (SMCs). The prototype short-term heating balloon catheter with 5.0, 5.5, 6.0 mm φ in balloon diameter and 25 mm in balloon length were employed. The short-term heating dilatation was performed in porcine iliac arteries with dilatation conditions of 75°C (N=4) and 65°C (N=5) as peak balloon temperature, 18 ± 4s as heating duration, 3.5 atm as balloon dilatation pressure. Four weeks after the balloon dilatation, the balloon-dilated artery segments were extracted and were stained with HE and picrosirius red for histological observation. In the case of 75°C as the peak balloon temperature, neointimal hyperplasia formation was significantly reduced. In this case, the SMCs density in the artery media measured from the HE-stained specimen was 20% lower than that in the reference artery. According to the thermal damage calculation, it was estimated that the SMCs lethality in artery media after the short-term heating angioplasty was 20% in the case of 75°C as the peak balloon temperature. We demonstrated that the short-term heating dilatation reduced the number of SMCs in artery media. We think this SMCs reduction might contribute to the suppression of chronic neointimal hyperplasia.

  7. MR-Guided Percutaneous Angioplasty: Assessment of Tracking Safety, Catheter Handling and Functionality

    SciTech Connect

    Wildermuth, Simon; Dumoulin, Charles L.; Pfammatter, Thomas; Maier, Stephan E.; Hofmann, Eugen; Debatin, Joerg F.

    1998-09-15

    Purpose: Magnetic resonance (MR)-guided percutaneous vascular interventions have evolved to a practical possibility with the advent of open-configuration MR systems and real-time tracking techniques. The purpose of this study was to assess an MR-tracking percutaneous transluminal angioplasty (PTA) catheter with regard to its safety profile and functionality. Methods: Real-time, biplanar tracking of the PTA catheter was made possible by incorporating a small radiofrequency (RF) coil in the catheter tip and connecting it to a coaxial cable embedded in the catheter wall. To evaluate potentially hazardous thermal effects due to the incorporation of the coil, temperature measurements were performed within and around the coil under various scanning and tracking conditions at 1.5 Tesla (T). Catheter force transmission and balloon-burst pressure of the MR-tracking PTA catheter were compared with those of a standard PTA catheter. The dilatative capability of the angioplasty balloon was assessed in vitro as well as in vivo, in an isolated femoral artery segment in a swine. Results: The degree of heating at the RF coil was directly proportional to the power of the RF pulses. Heating was negligible with MR tracking, conventional spin-echo and low-flip gradient-echo sequences. Sequences with higher duty cycles, such as fast spin echo, produced harmful heating effects. Force transmission of the MR-tracking PTA catheter was slightly inferior to that of the standard PTA catheter, while balloon-burst pressures were similar to those of conventional catheters. The MR-tracking PTA catheter functioned well both in vitro and in vivo. Conclusion: The in vivo use of an MR-tracking PTA catheter is safe under most scanning conditions.

  8. In vitro evaluation of paclitaxel coatings for delivery via drug-coated balloons.

    PubMed

    Kempin, Wiebke; Kaule, Sebastian; Reske, Thomas; Grabow, Niels; Petersen, Svea; Nagel, Stefan; Schmitz, Klaus-Peter; Weitschies, Werner; Seidlitz, Anne

    2015-10-01

    Lately, drug-coated balloons have been introduced in interventional cardiology as an approach to treat occluded blood vessel. They were developed for the rapid transfer of antiproliferative drugs during the angioplasty procedure in stenosed vessels with the intent to reduce the risk of restenosis. In this study five different paclitaxel (PTX) balloon coatings were tested in vitro in order to examine how solvents and additives influence coating stability and drug transfer rates. PTX-coated balloons were advanced through a guiding catheter and a simulated coronary artery pathway under perfusion and were then inflated in a hydrogel acceptor compartment. The fractions transferred to the gel, remaining on the balloon and the PTX lost in the simulated coronary pathway were then analysed. The results obtained suggest that the solvent used for the coating process strongly influences the surface structure and the stability of the coating. Ethanol/water and acetone based PTX coatings showed the lowest drug transfer rates to the simulated vessel wall (both <1%) due to their high drug losses during the prior passage through the coronary artery model (more than 95%). Balloons coated with PTX from ethyl acetate-solutions showed smaller drug loss (83%±9%), but most of the remaining PTX was not transferred (mean balloon residue approximately 15%). Beside the solvent, the use of additives seemed to have a great impact on transfer properties. The balloon pre-treatment with a crosslinked polyvinylpyrrolidone (PVP) film was able to increase the PTX transfer rate from less than 1% (without PVP) to approximately 6%. The best results in this study were obtained for balloon coatings with commercially available SeQuent© Please balloons containing the contrast agent iopromide. For this formulation drug transfer rates of approximately 17% were determined. Fluorescence microscopic imaging could visualize the particulate transfer of labelled PTX from the balloon surface during dilatation

  9. Laser-driven short-duration heating angioplasty: chronic artery lumen patency and histology in porcine iliac artery

    NASA Astrophysics Data System (ADS)

    Shimazaki, Natsumi; Kunio, Mie; Naruse, Sho; Arai, Tsunenori; Sakurada, Masami

    2012-02-01

    We proposed a short-duration heating balloon angioplasty. We designed a prototype short-duration heating balloon catheter that can heat artery media to 60-70°C within 15-25 s with a combination of laser-driven heat generation and continuous fluid irrigation in the balloon. The purpose of this study was to investigate chronic artery lumen patency as well as histological alteration of artery wall after the short-duration heating balloon dilatation with porcine healthy iliac artery. The short-term heating balloon dilated sites were angiographically patent in acute (1 hour) and in chronic phases (1 and 4 weeks). One week after the dilatation, smooth muscle cells (SMCs) density in the artery media measured from H&E-stained specimens was approx. 20% lower than that in the reference artery. One and four weeks after the dilatations, normal structure of artery adventitia was maintained without any incidence of thermal injury. Normal lamellar structure of the artery media was also maintained. We found that the localized heating restricted to artery media by the short-duration heating could maintain adventitial function and artery normal structure in chronic phase.

  10. Ballooning Interest in Science.

    ERIC Educational Resources Information Center

    Kim, Hy

    1992-01-01

    Presents an activity in which students construct model hot air balloons to introduce the concepts of convection current, the principles of Charles' gas law, and three-dimensional geometric shapes. Provides construction and launching instructions. (MDH)

  11. The Descending Helium Balloon

    ERIC Educational Resources Information Center

    Helseth, Lars Egil

    2014-01-01

    I describe a simple and fascinating experiment wherein helium leaks out of a rubber balloon, thereby causing it to descend. An estimate of the volumetric leakage rate is made by measuring its rate of descent.

  12. NASA Now: Balloon Research

    NASA Video Gallery

    In this NASA Now program, Debbie Fairbrother discusses two types of high-altitude balloons that NASA is using to test scientific instruments and spacecraft. She also talks about the Ideal Gas Law a...

  13. Qualifying Adjuncts Academic Worth and the Justification of Adjunct Work

    ERIC Educational Resources Information Center

    Pagnucco, Nicholas D.

    2012-01-01

    This dissertation studies the organization of adjunct instruction within Departments of English and Mathematics at three colleges--a public research university, a private masters granting teaching college, and a public community college. Four questions lie at the core of this project. First, what higher principles and standards of evaluation (i.e.…

  14. Angioplasty and Stenting of Symptomatic Vertebral Artery Stenosis

    PubMed Central

    Mohammadian, R.; Sharifipour, E.; Mansourizadeh, R.; Sohrabi, B.; Nayebi, A.R; Haririan, S.; Farhoudi, M.; Charsouei, S.; Najmi, S.

    2013-01-01

    Summary Percutaneous transluminal angioplasty (PTA) has recently become a noteworthy treatment option for significant stenosis involving the vertebral artery (VA) in selected patients. We conducted a prospective study to evaluate the efficacy, safety and mid-term follow up results of 206 cases received PTA with or without stent implant to treat their symptomatic atherosclerotic VA stenosis in all segments (V1-V4). In a prospective mono-arm trial from October 2008 to July 2012 in a single center, 239 lesions affecting the intra or extracranial VA (171 in V1, 17 in V2, 14 in V3, 21 in V4 and 16 in combined segments) were treated by PTA with or without stent implant. Non-disabling stroke patients who had failed conservative medical treatment and had angiographic evidence of >50% stenosis in the dominant VA with clinical signs and symptoms of VB stenosis were included in this study. They were mean followed for 13.15±5.24 months after treatment. Overall, 206 patients underwent the procedure. A stent was implemented in 199 patients (96.6%). The periprocedural complication rate was 7.2%. The procedural (technical) success rate was 97.6%. Of the total 239 lesions, 223 were treated with stent implant. Clinical success was achieved in all 206 symptomatic patients after the procedure. Restenosis occurred in 15.9% after a mean 10.8 (6-24) months. Of those, 63.1% and 34.2% had mild and moderate stenosis that was treated medically, whereas one case (2.6%) with severe restenosis underwent balloon angioplasty. No deaths occurred during the follow-up period. The follow-up complication rate was 6.3%. TIA occurred in 4.4%, a minor stroke in 1.4% and a major stroke in one patient. The overall patient event-free survival was 92.4%. These results demonstrate the safety and feasibility of PTA with or without stent implant, with a high technical success rate, a low complication rate, a low restenosis rate and durable clinical success in patients with symptomatic VA stenosis. This

  15. New developments in the clinical use of drug-coated balloon catheters in peripheral arterial disease

    PubMed Central

    Naghi, Jesse; Yalvac, Ethan A; Pourdjabbar, Ali; Ang, Lawrence; Bahadorani, John; Reeves, Ryan R; Mahmud, Ehtisham; Patel, Mitul

    2016-01-01

    Peripheral arterial disease (PAD) involving the lower extremity is a major source of morbidity and mortality. Clinical manifestations of PAD span the spectrum from lifestyle limiting claudication to ulceration and gangrene leading to amputation. Advancements including balloon angioplasty, self-expanding stents, drug-eluting stents, and atherectomy have resulted in high technical success rates for endovascular therapy in patients with PAD. However, these advances have been limited by somewhat high rates of clinical restenosis and clinically driven target lesion revascularization. The recent introduction of drug-coated balloon technology shows promise in limiting neointimal hyperplasia induced by vascular injury after endovascular therapies. This review summarizes the contemporary clinical data in the emerging area of drug-coated balloons. PMID:27418859

  16. Adjuncts Build Strength in Numbers

    ERIC Educational Resources Information Center

    June, Audrey Williams

    2012-01-01

    When professors in positions that offer no chance of earning tenure begin to stack the faculty, campus dynamics start to change. Growing numbers of adjuncts make themselves more visible. They push for roles in governance, better pay and working conditions, and recognition for work well done. And they do so at institutions where tenured faculty,…

  17. Alloplastic adjuncts in breast reconstruction

    PubMed Central

    Cabalag, Miguel S.; Rostek, Marie; Miller, George S.; Chae, Michael P.; Quinn, Tam; Rozen, Warren M.

    2016-01-01

    Background There has been an increasing role of acellular dermal matrices (ADMs) and synthetic meshes in both single- and two-stage implant/expander breast reconstruction. Numerous alloplastic adjuncts exist, and these vary in material type, processing, storage, surgical preparation, level of sterility, available sizes and cost. However, there is little published data on most, posing a significant challenge to the reconstructive surgeon trying to compare and select the most suitable product. The aims of this systematic review were to identify, summarize and evaluate the outcomes of studies describing the use of alloplastic adjuncts for post-mastectomy breast reconstruction. The secondary aims were to determine their cost-effectiveness and analyze outcomes in patients who also underwent radiotherapy. Methods Using the PRSIMA 2009 statement, a systematic review was conducted to find articles reporting on the outcomes on the use of alloplastic adjuncts in post-mastectomy breast reconstruction. Multiple databases were searched independently by three authors (Cabalag MS, Miller GS and Chae MP), including: Ovid MEDLINE (1950 to present), Embase (1980 to 2015), PubMed and Cochrane Database of Systematic Reviews. Results Current published literature on available alloplastic adjuncts are predominantly centered on ADMs, both allogeneic and xenogeneic, with few outcome studies available for synthetic meshes. Outcomes on the 89 articles, which met the inclusion criteria, were summarized and analyzed. The reported outcomes on alloplastic adjunct-assisted breast reconstruction were varied, with most data available on the use of ADMs, particularly AlloDerm® (LifeCell, Branchburg, New Jersey, USA). The use of ADMs in single-stage direct-to-implant breast reconstruction resulted in lower complication rates (infection, seroma, implant loss and late revision), and was more cost effective when compared to non-ADM, two-stage reconstruction. The majority of studies demonstrated

  18. Adjunct Control in Telugu and Assamese

    ERIC Educational Resources Information Center

    Haddad, Youssef A.

    2007-01-01

    My study explores Adjunct Control in two South Asian languages, Telugu (Dravidian) and Assamese (Indo-Aryan), within the Minimalist Program of syntactic theory. Adjunct Control is a relation of obligatory co-referentiality between two subjects, one in the matrix clause and one in an adjunct/subordinate clause of the same structure. Telugu and…

  19. Primary coronary angioplasty for acute myocardial infarction (the Primary Angioplasty Registry).

    PubMed

    O'Neill, W W; Brodie, B R; Ivanhoe, R; Knopf, W; Taylor, G; O'Keefe, J; Grines, C L; Weintraub, R; Sickinger, B G; Berdan, L G

    1994-04-01

    During a 14-month period, 6 experienced centers prospectively enrolled 271 patients into a registry in which percutaneous transluminal coronary angioplasty was the primary treatment for acute myocardial infarction. Patients age > 18 years who presented with ST-segment elevation on the 12-lead electrocardiogram were enrolled if symptom duration was < 12 hours and there was no proclivity for bleeding. An independent core angiographic laboratory processed the angiographic data. Of 271 patients giving informed consent, 245 (90%) were deemed anatomically suitable and underwent angioplasty therapy. Upon leaving the catheterization laboratory 98% of patients had achieved reperfusion; 92% had a residual visual stenosis < or = 50%. Emergency bypass surgery was required in 14 patients (5%) for either failed angioplasty (n = 3) or presumed life-threatening anatomy (n = 11). The in-hospital mortality rate was 4%, whereas the reinfarction rate was 3% and the stroke rate was 1%, with 1 intracranial hemorrhage and 2 embolic events. Bleeding requiring > or = 2 units of blood occurred in 46 patients (18%); 14 of these transfusions were related to coronary artery bypass surgery. Primary angioplasty is associated with a high reperfusion rate, low in-hospital mortality and few recurrent myocardial ischemic events. These results point to the need for a large-scale trial comparing angioplasty with thrombolytic therapy in the setting of acute myocardial infarction.

  20. Development of a balloon volume sensor for pulsating balloon catheters.

    PubMed

    Nolan, Timothy D C; Hattler, Brack G; Federspiel, William J

    2004-01-01

    Helium pulsed balloons are integral components of several cardiovascular devices, including intraaortic balloon pumps (IABP) and a novel intravenous respiratory support catheter. Effective use of these devices clinically requires full inflation and deflation of the balloon, and improper operating conditions that lead to balloon under-inflation can potentially reduce respiratory or cardiac support provided to the patient. The goal of the present study was to extend basic spirographic techniques to develop a system to dynamically measure balloon volumes suitable for use in rapidly pulsating balloon catheters. The dynamic balloon volume sensor system (DBVSS) developed here used hot wire anemometry to measure helium flow in the drive line from console to catheter and integrated the flow to determine the volume delivered in each balloon pulsation. An important component of the DBVSS was an algorithm to automatically detect and adjust flow signals and measured balloon volumes in the presence of gas composition changes that arise from helium leaks occurring in these systems. The DBVSS was capable of measuring balloon volumes within 5-10% of actual balloon volumes over a broad range of operating conditions relevant to IABP and the respiratory support catheter. This includes variations in helium concentration from 70-100%, pulsation frequencies from 120-480 beats per minute, and simulated clinical conditions of reduced balloon filling caused by constricted vessels, increased driveline, or catheter resistance.

  1. The 'MAP strategy' (Maximum aspiration of atherothrombus and adjunctive glycoprotein IIb/IIIa inhibitor utilization combined with prolonged inflation of balloon/stent) for preventing no-reflow in patients with ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention: A retrospective analysis of seventy-one cases.

    PubMed

    Potdar, Anil; Sharma, Satyavan

    2015-12-01

    'No-reflow' phenomenon is a common occurrence in percutaneous coronary intervention (PCI). A three-component 'MAP strategy' was designed to prevent no-reflow by addressing both intralesional and intraluminal thrombus in patients with ST-segment elevation myocardial infarction (STEMI). In this analysis, we observed Thrombolysis In Myocardial Infarction (TIMI) flow grade 3 or 2 in all patients, with no incidence of no-reflow. Myocardial blush grade (MBG) 3 or 2 was observed in most (87.32%) patients. Left ventricular ejection fraction (LVEF) was improved, without any incidence of death up to 9-month follow-up. All patients safely tolerated the strategy-driven prolonged, 35-s inflation of the balloon/stent.

  2. Universal stratospheric balloon gradiometer

    NASA Astrophysics Data System (ADS)

    Tsvetkov, Yury; Filippov, Sergey; Brekhov, Oleg; Nikolaev, Nikolay

    The study of the interior structure of the Earth and laws of its evolution is one of the most difficult problems of natural science. Among the geophysical fields the anomaly magnetic field is one of the most informational in questions of the Earth’s crust structure. Many important parameters of an environment are expedient for measuring at lower altitudes, than satellite ones. So, one of the alternatives is stratospheric balloon survey. The balloon flight altitudes cover the range from 20 to 50 km. At such altitudes there are steady zone air flows due to which the balloon flight trajectories can be of any direction, including round-the-world (round-the-pole). For investigation of Earth's magnetic field one of the examples of such sounding system have been designed, developed and maintained at IZMIRAN and MAI during already about 25 years. This system consists of three instrumental containers uniformly placed along a vertical 6 km line. Up today this set has been used only for geomagnetic purposes. So we describe this system on example of the measuring of the geomagnetic field gradient. System allows measuring a module and vertical gradient of the geomagnetic field along the whole flight trajectory and so one’s name is - stratospheric balloon magnetic gradiometer (SMBG). The GPS-receivers, located in each instrumental container, fix the flight coordinates to within several tens meters. Process of SBMG deployment, feature of the exit of rope from the magazine at the moment of balloon launching has been studied. Used magazine is cellular type. The hodograph of the measuring base of SBMG and the technique of correction of the deviations of the measuring base from the vertical line (introduction of the amendments for the deviation) during the flight have been investigated. It is shown that estimation of the normal level of values of the vertical gradient of the geomagnetic field is determined by the accuracy of determining the length of the measuring base SBMG

  3. Gradient magnetometer system balloons

    NASA Astrophysics Data System (ADS)

    Korepanov, Valery; Tsvetkov, Yury

    2005-08-01

    Earth's magnetic field study still remains one of the leading edges of experimental geophysics. Thus study is executed on the Earth surface, including ocean bottom, and on satellite heights using component, mostly flux-gate magnetometers. But balloon experiments with component magnetometers are very seldom, first of all because of great complexity of data interpretation. This niche still waits for new experimental ideology, which will allow to get the measurements results with high accuracy, especially in gradient mode. The great importance of precise balloon-borne component magnetic field gradient study is obvious. Its technical realization is based both on the available at the marked high-precision non-magnetic tiltmeters and on recent achievements of flux-gate magnetometry. The scientific goals of balloon-borne magnetic gradiometric experiment are discussed and its practical realization is proposed.

  4. Stability of lobed balloons

    NASA Astrophysics Data System (ADS)

    Pagitz, M.; Xu, Y.; Pellegrino, S.

    This paper presents a computational study of the stability of simple lobed balloon structures. The particular structure that is investigated is a stack of pumpkin-shaped envelopes with a common axis of symmetry, and hence forming a kind of lobed cylinder. The number of the pumpkin envelopes is one of the variables that is investigated; a number of shape imperfections are also considered. This lobed cylinder is an axi-symmetric, idealised version of the lobed pumpkin balloons that have occasionally deployed into anomalous, clefted configurations. By studying in detail the behaviour of lobed cylinder we are able to draw some preliminary conclusions about general features of the behaviour of lobed pumpkin balloons.

  5. Balloon gondola diagnostics package

    NASA Astrophysics Data System (ADS)

    Cantor, K. M.

    1986-10-01

    In order to define a new gondola structural specification and to quantify the balloon termination environment, NASA developed a balloon gondola diagnostics package (GDP). This addition to the balloon flight train is comprised of a large array of electronic sensors employed to define the forces and accelerations imposed on a gondola during the termination event. These sensors include the following: a load cell, a three-axis accelerometer, two three-axis rate gyros, two magnetometers, and a two axis inclinometer. A transceiver couple allows the data to be telemetered across any in-line rotator to the gondola-mounted memory system. The GDP is commanded 'ON' just prior to parachute deployment in order to record the entire event.

  6. BARREL Team Launching 20 Balloons

    NASA Video Gallery

    A movie made by the NASA-Funded Balloon Array for Radiation belt Relativistic Electron Losses, or BARREL, team on their work launching 20 balloons in Antarctica during the Dec. 2013/Jan. 2014 campa...

  7. Heimlich manoeuvre: adjunctive emergency procedure to relieve choking and asphyxia.

    PubMed

    du Toit, D F

    2004-02-01

    Choking on aspirated food or a foreign body (i.e. meat, mushroom, coin, chewing gum and a balloon) is a common cause of laryngeal obstruction, particularly in those persons who are intoxicated by alcohol or who have bulbar palsy (degeneration of motor neurons in the brain stem nuclei of the glossopharyngeal and vagal nerve). The rima glottis in the larynx is an important site where aspirated food or material becomes lodged, thereby causing laryngeal obstruction (choking). Because the lungs still contain air, intentional compression thrusts to the abdomen (Heimlich manoeuvre) will theoretically expel air from the lungs and dislodge the entrapped food or other material. The manoeuvre can also be used to expel aspirated water from the airways in cases of near drowning. The manoeuvre has been found to be successful as an emergency adjunct measure in removing food blocking the airway.

  8. Experimental analysis of sapphire contact probes for Nd-YAG laser angioplasty.

    PubMed

    Ashley, S; Brooks, S G; Gehani, A A; Kester, R C; Rees, M R

    1990-06-01

    Laser angioplasty may offer percutaneous recanalization of occluded vessels where conventional guidewire and balloon techniques fail. Metal laser thermal angioplasty probes may, however, cause excessive thermal damage due to high tip temperatures (greater than 400.C). Therefore, contact probes made from artificial sapphire crystal designed for general laser surgery are currently being evaluated for use in laser angioplasty with continuous wave Nd-YAG energy. The sapphire modifies the laser energy in various ways, and this paper examines the physical characteristics of five types of rounded sapphire probe (SMTR, MTR, MTRL, OS, LT) and how these properties are affected by clinical usage. The laser beam profile emitted by these probes demonstrates a focal spot 1-2 mm in front of the tip. However, the forward transmission of Nd-YAG energy through the sapphires varied (SMTR, 85%; MTR, 83%; MTRL, 75%; OS, 54%; LT, 69%). Probe heating occurs owing to energy absorption within the sapphire. The surface temperature of the sapphires was measured in air by infrared thermography and the hottest region within the probes localized by an isothermographic technique. At energy settings used clinically (20 J, 10 watts for 2 s) the SMTR, MTR, and MTRL probes exhibited higher temperature rises (94-112.C) than the OS and LT probes (30.C), and heating was localized to the front surface of the former probes. Peak sapphire temperatures remained lower than those of metal probes even at higher energies. After clinical use, the MTR probe demonstrated reduced transmission, beam defocusing, and increased heating, due to surface pitting. Thus, recanalization with sapphire probes occurs by a combination of photothermal and contact thermal effects that are localized to the probe tip and may reduce the degree of thermal injury associated with metal probes. Understanding these basic properties is important to the application and development of contact probes for laser recanalization.

  9. Intravascular Ultrasound and Histology in In Vitro Assessment of Iliac Artery Angioplasty

    SciTech Connect

    Lankeren, Winnifred van; Gussenhoven, Elma J.; Qureshi, Akeel; Lugt, Aad van der

    1999-01-15

    Purpose: Intravascular ultrasound (IVUS) was used to assess in vitro the morphologic and quantitative effects of balloon angioplasty (PTA) of the iliac artery. Methods: Forty human iliac arteries ({>=} 30% area stenosis) were studied with IVUS in vitro before and after PTA and the findings were validated with histology. Results: The sensitivity of IVUS for dissection was 74% and for media rupture 59%. The incidence of vascular damage was higher when the whole segment was analyzed rather than the target site alone. Dissections occurred at the thinnest region of the plaque, unrelated to plaque calcification. Following PTA, quantitative changes at the target site were greater compared with the overall data derived from all cross-sections. The increase in lumen area was caused solely by an increase in vessel area. Conclusions: IVUS is sensitive in detecting dissections, which occurred irrespective of calcification at the thinnest region of the plaque. The increase in lumen area after PTA was caused by stretching of the vessel.

  10. Angioplasty and stent placement - carotid artery

    MedlinePlus

    ... correct position. Next, the surgeon will move a wire through the catheter to the blockage. Another catheter ... on the end will be pushed over this wire and into the blockage. Then the balloon is ...

  11. Angioplasty - Multiple Languages: MedlinePlus

    MedlinePlus

    ... sharing features on this page, please enable JavaScript. Arabic (العربية) Bosnian (Bosanski) Chinese - Simplified (简体中文) Chinese - Traditional ( ... Somali (af Soomaali) Spanish (español) Vietnamese (Tiếng Việt) Arabic (العربية) Heart Cath and Heart Angioplasty (Arabic) شرايين ...

  12. Balloons of the Civil War

    DTIC Science & Technology

    1994-06-03

    summer. The indirect path involved transporting the Army of the Potomac south, via the water network , to some point nearer Richmond, and thence...using the telegraph. and signal stations near his balloons to communicate with headquarters. Logistic support for the balloons flowed via the water ... network to Aquia Creek Station Landing and then overland to the balloon camps. Two of four balloons available were sent back to Washington for repairs

  13. Balloon borne Infrared Surveys

    NASA Astrophysics Data System (ADS)

    Lubin, Philip M.

    2015-08-01

    We report on modeling of a balloon borne mission to survey the 1-5 micron region with sensitivity close to the zodiacal light limits in portions of this band. Such a survey is compelling for numerous science programs and is complimentary to the upcoming Euclid, WFIRST and other orbital missions. Balloons borne missions offer much lower cost access and rapid technological implementation but with much less exposure time and increased backgrounds. For some science missions the complimentary nature of these is extremely useful. .

  14. The value of occlusive balloons in the management of abnormal placentation: A retrospective study.

    PubMed

    Omar, H R; Sprenker, C; Alvey, E; Hoffman, M; Karlnoski, R; Ching, Y-H; Cain, M; Mangar, D; Camporesi, E M

    2016-01-01

    Abnormal placentation is a potential cause of maternal morbidity and mortality from massive postpartum bleeding. The objective of this study was to investigate the efficacy of occlusive balloons when used as an adjunct to surgery in reducing blood loss and transfusion requirements. A retrospective study of 42 patients was performed involving consecutive cases of abnormal placentation who delivered with either conventional surgery with preoperatively placed occlusive balloons or conventional surgery alone. No differences were noted between the control group and the group of patients who had occlusive balloons with regard to estimated blood loss (P = 0.767), packed red blood cells transfused (P = 0.799), amount of crystalloids infused (P = 0.435), total procedure duration (P = 0.076), and length of ICU stay (P = 0.315) or total hospital stay (P = 0.254). Prophylactic intravascular balloon catheters did not benefit women with abnormal placentation when compared with conventional surgery alone.

  15. Extracranial carotid angioplasty and stenting. Initial results and short-term follow-up.

    PubMed Central

    Vozzi, C R; Rodriguez, A O; Paolantonio, D; Smith, J A; Wholey, M H

    1997-01-01

    Carotid percutaneous transluminal angioplasty, with or without stent implantation, is becoming another therapeutic option for carotid revascularization. To evaluate the feasibility and effectiveness of the technique, from October of 1995 to March of 1997, we performed 24 percutaneous transluminal angioplasty procedures in 22 patients with severe extracranial carotid artery stenosis. Three common carotid and 21 internal carotid arteries were treated, and 19 procedures included stent implantation using nonarticulated PALMAZ stents (P154 and P204). Twelve patients were asymptomatic and 10 patients were symptomatic; 2 of the symptomatic patients had complete obstruction of the internal carotid artery that was successfully recanalized. Technical and angiographic success was achieved in 23 of 24 procedures, with the carotid artery obstruction diminishing from 85.6% +/- 8.5% to 5.7% +/- 3.2% (P < 0.001). Average stenosis length was 12.5 +/- 3.1 mm, and mean time of carotid occlusion during balloon inflation was 11.5 +/- 2.5 seconds. Three patients experienced transitory seizures during the procedure prior to dilation, 1 patient had a minor stroke with complete recovery within 72 hours, and 1 patient had a major stroke and died 45 days after the procedure. Clinical follow-up was achieved in all patients (mean, 10.5 +/- 7.2 months) and angiographic follow-up in 16 patients (mean, 6.3 +/- 1.2 months). The results obtained in this initial experience provide adequate support to continue further evaluation of this new therapeutic strategy. Images PMID:9339503

  16. Primary success and one-year followup of percutaneous peripheral excimer laser angioplasty

    NASA Astrophysics Data System (ADS)

    Visona, Adriana; Liessi, Guido; Miserocchi, Luigi; Bonanome, Andrea; Lusiani, Luigi; Breggion, Giovanni; Pagnan, Antonio

    1992-08-01

    Excimer laser angioplasty was performed in 59 patients (44 males and 17 females, mean age 63 +/- 9 years, range 39 - 77) affected by peripheral vascular disease. Fifty patients had a total occlusion of the superficial femoral artery, three of the iliac artery, and one of the popliteal artery; seven patients showed a subocclusive stenosis of the superficial femoral artery. A commercial excimer laser (Technolas Max-10) was used at the Xenon-Chloride wavelength of 308 nm. The laser operated at 120 ns pulse length and at 20 Hz repetition rate. Applied energy fluence was 20 mJ/pulse. The energy was delivered through a multifiber catheter, which combines 12 (7F) or 18 (9F) fibers (260 micron diameter each), concentrically arranged. Balloon dilatation was associated in 51 patients. Successful recanalization was obtained in 59 out of 61 patients (97%). Failure to recanalize the occluded arteries occurred in two cases, and was due to dissection. Early thrombosis and reocclusion (within 48 hours) was observed in five patients. The cumulative patency rate was 56% at one year. On the basis of these results, excimer laser assisted angioplasty seems a feasible and safe procedure. However, this technique did not solve the restenosis problem. A wide application of excimer laser as a stand alone approach can be foreseen for treatment of peripheral vascular disease.

  17. Frequent Embolization in Peripheral Angioplasty: Detection with an Embolism Protection Device (Angio Guard) and Electron Microscopy

    SciTech Connect

    Koenig, Claudius W. Pusich, Benjamin; Tepe, Gunnar; Wendel, Hans-Peter; Hahn, Ulrich; Schneider, Wilke; Claussen, Claus D.; Duda, Stephan H.

    2003-08-15

    Purpose: To evaluate the deliverability and protection capabilities of an embolism protection filter in angioplasty of peripheral arteries. Methods: The Angioguard emboli capture guidewire system was applied in 11 patients with femoropopliteal lesions (6 stenoses, 3 occlusions, 2 controls).Data on lesion crossing, flow deceleration and macroembolization were recorded. Filter membranes were evaluated with scanning electron microscopy (SEM). Results: System delivery was successful in all patients. Primary lesion crossing was feasible in four of six stenoses; predilatation was required in two of six. Marked flow deceleration was recorded in six patients. Emboli next to the filter were detected in each patient with concentric plaques, but could not reliably be removed with the filter. Downstream macroembolization was also present in all patients with concentric stenoses, but in none with chronic occlusion. None of the patients had clinical signs of ischemia. SEM analysis demonstrated only small particles on control group filters and non-obliterating fibrinous conglomerates on filters used in chronic occlusion. Substantial obliteration was seen on several filters used in stenotic lesions. Conclusion:Microembolization of fibrin aggregates is a common incident in balloon angioplasty of femoropopliteal stenoses. Macroembolization occurred more frequently than previously reported. The use of embolism protection filters aided in the detection but not in the removal of larger emboli.

  18. [Multifunctional testing of PTCA balloon catheters].

    PubMed

    Kraft, M; Schmitz, H; Schulte, R; Boenick, U

    2000-06-01

    New in vitro measuring methods for balloon catheters used for percutaneous transluminal coronary angioplasty (PTCA) and their verification in a complex test device are presented. This system can mimic all relevant application situations. The central element of the test device is a coronary vessel model matching the physiological situation in terms of geometrical structure and frictional properties. Reactive force sensors are used to measure the application-relevant forces exerted by the catheter on the model vessel walls and accessories, such as guide wire and guiding catheter. To generate a kink-free advancement of the catheter and permit measurement of the active forces, an alternating drive unit has been specially developed. The testing and application of the newly developed methods revealed statistically significant differences between various types of catheter. The test device closes a gap between complex but subjective clinical tests, and individual objective, but application-removed in vitro test setups for PTCA catheters. While the initial prototype had shortcomings with regard to the reproducibility of measurements, successor systems developed for industrial use are now in production. The properties of these measuring systems developed for the benefit of manufacturer and reprocessor of PTCA catheters are discussed.

  19. [Incidence and management of acute left main coronary artery dissection as a complication of acute transluminal coronary angioplasty].

    PubMed

    Dittel, M; Prachar, H; Spiel, R; Mlczoch, J

    1996-09-01

    Out of 1730 consecutive patients undergoing percutaneous transluminal coronary angioplasty (PTCA) of left descending coronary artery (LAD) or circumflex artery (CX) five patients (0.3%) suffered an acute dissection of left main coronary artery. In three patients dissection developed because of manipulation of the guiding catheter. In one patient retrograde dissection of the left main stem occurred because of balloon angioplasty of ostial LAD stenosis and in a second patient because of balloon rupture in the setting of stent deployment in the proximal part of the LAD. Four patients were selected for emergency operation, but one patient died before reacting the operation theatre. Out of the three remaining patients one patient died postoperatively and another patient suffered a transmural myocardial infarction. In the fifth patient three AVE Micro stents were implanted; one just at the origin of the LAD, one at the origin of the CX and the third in the left main stem. This patient was not sent for operation and was discharged without symptoms.

  20. Recent developments in scientific ballooning and launching of stratopause balloon

    NASA Astrophysics Data System (ADS)

    Buduru, Suneel Kumar

    2012-07-01

    The Balloon Facility, Hyderabad has been launching stratospheric zero pressure balloons for scientific, engineering experiments and sounding balloons for getting winds at balloon float altitudes. Sounding balloons of volume 4,000 cubic meters made with thin film of 5.8 microns can reach up to 43 kilometers with a maximum payload of 1 kilogram. To keep pace with growing demand from user scientists in terms of higher payload capability and higher float altitude, developmental work in the area of very thin film continued, resulting in the development of very thin film of 3.8 microns thickness. Using this very thin film, four balloons of volume 60,000 cubic meters each, capable of carrying 10 kilograms payload to stratopause (approximately 47 kilometers) were fabricated for the first time for trial and evaluation. These balloons are precursors to our ultimate aim of developing still thinner film of 2.7 microns, to be used in balloons for reaching mesosphere with 10 kilogram payload. Raw material selection, manufacturing process, test and evaluation of the film in laboratory, new launching techniques for handling the very thin film balloons are described. A summary of the successful balloon flights carried out in last two years for scientific experiments and launching results of very thin film balloon is presented.

  1. Scientific balloons: historical remarks.

    NASA Astrophysics Data System (ADS)

    Ubertini, P.

    The paper is an overview of the Human attempt to fly, from the myth of Daedalus and his son Icarus to the first "aerostatic" experiment by Joseph-Michel and Jaques-Etienne Montgolfier. Then, via a jump of about 200 years, we arrive to the era of the modern stratospheric ballooning that, from the beginning of the last century, have provided a unique flight opportunity for aerospace experiments. In particular, the Italian scientific community has employed stratospheric balloons since the '50s for cosmic rays and high energy astrophysical experiments with initial launches performed from Cagliari Helmas Airport (Sardinia). More recently an almost ideal location was found in the area of Trapani-Milo (Sicily, Italy), were an old abandoned airport was refurbished to be used as a new launch site that became operative at the beginning of the '70s. Finally, we suggest a short reminiscence of the first transatlantic experiment carried out on August 1975 in collaboration between SAS-CNR (Italy) and NSBF-NASA (USA). The reason why the Long Duration Balloon has been recently re-oriented in a different direction is analysed and future perspectives discussed. Finally, the spirit of the balloon launch performed by the Groups lead by Edoardo Amaldi, Livio Scarsi and other Italian pioneers, with payloads looking like "refrigerators" weighting a few tens of kg is intact and the wide participation to the present Workshop is the clear demonstration.

  2. Particle Astrophysics Using Balloons

    NASA Astrophysics Data System (ADS)

    Seo, E. S.

    Cosmic rays, energetic particles coming from outer space, bring us information about the physical processes that accelerate particles to relativistic energies, about the effects of those particles in driving dynamical processes in our Galaxy, and about the distribution of matter and fields in interstellar space. Cosmic rays were discovered in the early twentieth century using a balloon-borne electroscope. Balloons are currently being used for answering fundamental questions about the cosmos: (1) Is the Universe symmetric, and if so where is the antimatter? (2) What is the dark matter? (3) How do cosmic rays get their enormous energies? (4) Can the entire energy spectrum of cosmic rays result from a single acceleration mechanism? (5) Are supernovae really the sources of cosmic rays? (6) What is the history of cosmic rays in the Galaxy? (7) What is the origin of the "knee" in the cosmic ray energy spectrum? etc. The status of results from past balloon-borne measurements and expected results from ongoing and planned future balloon-borne particle astrophysics experiments will be reviewed.

  3. Flow Past a Descending Balloon

    NASA Technical Reports Server (NTRS)

    Baginski, Frank

    2001-01-01

    In this report, we present our findings related to aerodynamic loading of partially inflated balloon shapes. This report will consider aerodynamic loading of partially inflated inextensible natural shape balloons and some relevant problems in potential flow. For the axisymmetric modeling, we modified our Balloon Design Shape Program (BDSP) to handle axisymmetric inextensible ascent shapes with aerodynamic loading. For a few simple examples of two dimensional potential flows, we used the Matlab PDE Toolbox. In addition, we propose a model for aerodynamic loading of strained energy minimizing balloon shapes with lobes. Numerical solutions are presented for partially inflated strained balloon shapes with lobes and no aerodynamic loading.

  4. Application of drug-coated balloon in coronary artery intervention: challenges and opportunities

    PubMed Central

    GAO, Lei; CHEN, Yun-Dai

    2016-01-01

    In recent decades, the outcomes of coronary heart disease (CHD) have markedly improved, which can be partly attributed to the use of novel drugs (especially statins and antiplatelet drugs) and partly to the evolution of percutaneous coronary intervention (PCI). From percutaneous transluminal coronary angioplasty to bare-metal stent and then to drug-eluting stent, every step of PCI is attractive to interventional cardiologist, great progress has been made for patients with CHD. In the past few years, some successor devices for treating CHD have emerged. Undoubtedly, drug-coated balloon (DCB), which was recommended by 2014 ESC Guidelines on myocardial revascularization, is a “shining star” among them. DCB involves a semi-compliant angioplasty balloon coated with an anti-proliferative agent that can exert antirestenotic efficacy by permeating into the vessel wall during balloon contact. This review discusses the conception and merits, preclinical data, emerging clinical indications, and results from clinical trials of this novel interventional technology. Although DCB has shown authentic efficacy in the treatment of in-stent restenosis, its use in de novo coronary lesions is still in dispute. Hence, concerns and the future direction of DCB are also covered in this paper. PMID:28133467

  5. Venus Balloons using Water Vapor

    NASA Astrophysics Data System (ADS)

    Izutsu, N.; Yajima, N.; Honda, H.; Imamura, T.

    We propose an inflatable balloon using water vapor for the lifting gas, which is liquid in the transportation stage before entry into the high temperature atmosphere. The envelope of the balloon has an outer layer for gas barrier (a high-temperature resistant film) and an inner layer for liquid water keeping. In the descent stage using a parachute, water widely held just inside the balloon envelope can be quickly vaporized by a lot of heat flux from the surrounding high-temperature atmosphere owing to the large surface area of the balloon. As neither gas containers nor heat exchangers are necessary, we can construct a simple, lightweight and small size Venus balloon probe system. Tentative floating altitude is 35 km below the thick clouds in the Venusian atmosphere. Selection of balloon shape and material for balloon envelope are discussed in consideration of the Venusian environment such as high-temperature, high-pressure, and sulfuric acid. Balloon deployment and inflation sequence is numerically simulated. In case of the total floating mass of 10 kg at the altitude of 35 km, the volume and mass of the balloon is 1.5 cubic meters, and 3.5 kg, respectively. The shape of the balloon is chosen to be cylindrical with a small diameter. The mass of li fting gas can be determined as 4.3 kg and the remaining 2.2 kg becomes the payload mass. The mass of the total balloon system is also just 10 kg excluding the entry capsule.

  6. Optimum Designs for Superpressure Balloons

    NASA Astrophysics Data System (ADS)

    Smith, M.; Rainwater, E.

    Natural shape balloons have been employed for minimum stress envelope design in zero pressure scientific balloons since the 1940's. Superpressure balloons, on the other hand, have traditionally been spheres with tangential load attachment points. Application of natural shape design principles to superpressure balloons is relatively new. The resulting natural shape superpressure balloon shape generally fits Euler's Elastica. There are numerous examples of superpressure cylinder balloons which take on the elastica shape when pressurized. Techniques tried for reducing circumferential stresses in the NASA ULDB natural shape superpressure balloons have revealed new challenges both for design and manufacture. This paper will present a thorough background in the development of the current design concept as well as a review of the current challenges associated with manufacturing these envelopes. Approaches for achieving an optimum design will be presented along with ground and flight test data.

  7. Comparative assessment of drug-eluting balloons in an advanced porcine model of coronary restenosis.

    PubMed

    Joner, M; Byrne, R A; Lapointe, J-M; Radke, P W; Bayer, G; Steigerwald, K; Wittchow, E

    2011-05-01

    The advent of drug-eluting balloon (DEB) therapy has represented an important development in interventional cardiology. Nevertheless, preclinical data with this technology remain scant, and comparative studies have not previously been published. Bare metal stents were implanted in the coronary arteries of 15 pigs followed by balloon angioplasty. Animals were allocated to treatment with a 60-second inflation of one of four different balloon catheters: a conventional untreated plain angioplasty balloon (PBA, Biotronik AG), the Pantera Lux DEB (3.0 μg/mm2 paclitaxel; BTHC excipient, Biotronik AG), the Elutax DEB (2.0 μg/mm2 paclitaxel; no excipient; Aachen Resonance), or the SeQuent Please DEB (3.0 μg/mm2 paclitaxel; iopromide excipient: B. Braun). Twenty-eight days following balloon deployment, animals underwent repeat angiography for quantitative coronary angiography analysis and euthanasia for histopathologic assessment. By histology, the mean neointimal thickness was 0.44 ± 0.19 mm with PBA, 0.35 ± 0.13 mm with Pantera Lux , 0.61 ± 0.20 mm with Elutax , and 0.47 ± 0.21 mm with SeQuent Please DEB (p=0.02). In comparison with PBA, deployment of the Pantera Lux or the SeQuent Please DEB resulted in delayed healing characterised by significant increases in fibrin, neointimal cell vacuity and delayed re-endothelialisation. In conclusion, investigation of comparative DEB performance in a porcine model of advanced coronary restenosis reveals significant heterogeneity of neointimal suppression between the devices tested with numerically lowest values seen in the Pantera Lux group. On the other hand, evidence of delayed healing was observed in the most effective DEB groups.

  8. Assessment of computer-controlled inflation/deflation for determining the properties of PTCA balloon catheters with pressure-volume curves.

    PubMed

    Olbrich, T; Murray, A

    2001-05-01

    Restenosis is a significant problem after percutaneous transluminal coronary angioplasty (PTCA), leading to further angina or even death. The mechanisms causing restenosis are not well understood and the effect of the angioplasty balloon on the artery wall is generally unknown. The aim of the research presented here was to assess the repeatability with which measurements of balloon pressure-volume characteristics could be made, to ensure that different balloons could be distinguished easily, an essential first step before the arteries themselves could be characterized. An inflation/deflation device was inflated with and without an attached balloon under computer control at a constant speed to 8 bar. The accuracy and repeatability of the technique was assessed within a single measurement session and between measurement sessions on six separate days. For each measurement session, four repeated inflations/deflations were carried out and the average was determined. Compliance (volume change/pressure change), inflation volume and pressure drop at 8 bar were determined for various balloon catheters of different size, type and manufacturer. The system repeatability SD for measuring volume without a balloon was +/- 0.0005 ml within a single measurement session, and +/- 0.002 ml between independent days. With an attached balloon the repeatability SD for measuring volume was +/- 0.001 ml within, and +/- 0.003 ml between days. Compliance was determined with a repeatability SD of +/- 0.16 microliter bar-1 within, and +/- 0.94 microliter bar-1 between days. The inflation/deflation device and technique employed allowed small changes in volume and compliance to be differentiated. The system also enabled differences due to the material characteristics for different PTCA balloons to be determined. Measured balloon characteristics were similar to the data given by manufacturers. This gives confidence in development of the technique for clinical use.

  9. Early and Long-Term Results of Subclavian Angioplasty in Aortoarteritis (Takayasu Disease): Comparison with Atherosclerosis

    SciTech Connect

    Tyagi, Sanjay; Verma, Puneet K.; Gambhir, Daljeet S.; Kaul, Upkar A.; Saha, Renuka; Arora, Ramesh

    1998-05-15

    Purpose: To compare the early andlong-term outcomes of subclavian artery angioplasty in patients with aortoarteritis and atherosclerosis. Methods: Sixty-one subclavian artery angioplasties were performed in 55 consecutive patients with aortoarteritis (n= 32) and atherosclerosis (n= 23) between 1986 and 1995. An arch aortogram followed by a selective subclavian artery angiogram was done to profile the site and extent of the lesion, its relation to the vertebral artery, and the distal circulation. Percutaneous transluminal angioplasty (PTA) was performed via the femoral route for 56 stenotic lesions and 5 total occlusions. Results: PTA was successful in 52 (92.8%) stenotic lesions and 3 (60%) total occlusions. Three patients (5.4%) had complications, that could be effectively managed nonsurgically. Compared with atherosclerosis, patients with aortoarteritis were younger (27.4 {+-} 9.3 years vs 54.5 {+-} 10.5 years; p < 0.001), more often female (75% vs 17.4%; p < 0.001), gangrene was uncommon (0% vs 17.4%; p < 0.05), and diffuse involvement was seen more often (43.8% vs 4.4%; p < 0.001). The luminal diameter stenoses were similar before PTA (88.6 {+-} 9.7% vs 89.0 {+-} 9.1%; p= NS). Higher balloon inflation pressure was required to dilate the lesions of aortoarteritis (9.9 {+-} 4.6 ATM vs 5.5 {+-} 1.0 ATM; p < 0.001). This group had more residual stenosis (15.5 {+-} 12.4% vs 8.3 {+-} 9.4%; p < 0.05) after PTA. There were no neurological sequelae, even in PTA of prevertebral lesions. On 3-120 months (mean 43.3 {+-} 28.9 months) follow-up of 40 patients, restenosis was more often observed in patients with aortoarteritis, particularly in those with diffuse arterial narrowing. These lesions could be effectively redilated. Clinical symptoms showed marked improvement after successful angioplasty. Conclusion: Subclavian PTA is safe and can be performed as effectively in aortoarteritis as in atherosclerosis, with good long-term results. Long-term follow-up shows that it

  10. Results of balloon atrial septostomy as preparation for surgical correction in transposition of great arteries.

    PubMed

    Padilla, Tatiana; Zapata, Margarita; Díaz, Luis Horacio; Lince, Rafael; Ruz, Miguel; Guzmán, Mónica; Donado, Juan; Franco, Gloria

    2011-04-01

    Balloon atrial septostomy (BAS) is a palliative procedure performed in the preoperative management of patients with transposition of great arteries (TGA), to improve the mixing of blood between the 2 systems. This report describes experience at the Clínica Cardiovascular Santa Maria in Medellin, Colombia. Between 2002 and 2010, 22 patients with TGA underwent BAS. Patient age at the time of the procedure was 21 days on average; 68% of patients were male. Average weight was 2.96 kg and interatrial gradient was between 4 and 12 mm Hg. The average systemic oxygen saturation at the beginning of the procedure was 60%, with a final saturation of 90%. Z5 atrioseptostomy balloons were used in 18 patients (81%), using Rashkind technique; Tyshak balloon catheters were used in 3 patients (13%) with the Shrivastava technique; and static high-pressure peripheral angioplasty balloons were used in 3 patients (13%). Two patients underwent BAS with 2 types of balloons. Although there were no complications clearly attributable to the procedure, 14% of patients had evidence of focal brain injury on the postoperative magnetic resonance image. Six patients died (27%), 5 of them because of postoperative complications and 1 because of infectious complications at another institution. All postoperative deaths occurred before 2006. The BAS is a safe technique for preoperative stabilization of patients with TGA.

  11. The current status of drug-coated balloons in percutaneous coronary and peripheral interventions.

    PubMed

    Loh, Joshua P; Barbash, Israel M; Waksman, Ron

    2013-12-01

    Through continued innovation, percutaneous treatment of coronary and peripheral stenoses has evolved rapidly since balloon angioplasty was first introduced three decades ago. Significant advances were made with the introduction of bare metal stents and subsequently drug-eluting stents, which expanded the possibility of successful revascularisation in complicated lesions. Despite these advantages, efforts are still ongoing to improve patient outcomes further. In recent years, drug-coated balloons have emerged as an exciting technology developed to overcome the limitations faced by drug-eluting stents, such as stent thrombosis and dependency on prolonged dual antiplatelet therapy, and may prove efficacious in complex subsets such as small vessels and diffuse lesions where stent results are suboptimal. Several drug-coated balloons developed for coronary and peripheral applications were evaluated recently in preclinical and clinical studies with encouraging results. Drug-coated balloons have proven effective in treating in-stent restenosis; however, there is accumulating evidence on their utility in other clinical scenarios. We present a timely review of the mechanisms of action, key preclinical studies, emerging clinical indications, current clinical trial results, and future perspectives of this novel drug-coated balloon technology as it seeks to establish its role in percutaneous intervention.

  12. Characteristics of smooth muscle cells' shape and proliferation rate in novel short-term thermal angioplasty ex vivo and in vitro.

    PubMed

    Kunio, Mie; Shimazaki, Natsumi; Ito, Arisa; Hayashi, Tomoaki; Arai, Tsunenori

    2010-01-01

    We investigated the influences on the smooth muscle cells of temporally heated arterial walls in both ex vivo and in vitro study to determine the optimum heat parameter of novel short-term thermal angioplasty, Photo-thermo Dynamic Balloon Angioplasty (PTDBA). Arterial heating dilatation was performed by the prototype PTDBA balloon ex vivo. We found that the smooth muscle cells in the vessel wall were stretch-fixed after the heating dilatation ex vivo. The stretch-fixing rate of these cells was increased with the temperature rise in the balloon of PTDBA from 60 °C to 70 °C. We measured the proliferation rate of the stretch-fixed smooth muscle cells, which were extracted from porcine arteries, on specially designed culture equipment in vitro. It was observed that the proliferation rate was inhibited at 20 % stretching compared to 10 % stretching. We think the stretch-fixing of the smooth muscle cells might not be harmful for PTDBA performances.

  13. Primary Infrainguinal Subintimal Angioplasty in Diabetic Patients

    SciTech Connect

    Bargellini, Irene Petruzzi, Pasquale; Scatena, Alessia; Cioni, Roberto; Cicorelli, Antonio; Vignali, Claudio; Rizzo, Loredana; Piaggesi, Alberto; Bartolozzi, Carlo

    2008-07-15

    The aim of this study was to prospectively evaluate technical and clinical results of infrainguinal subintimal angioplasty in a series of diabetic patients with limb-threatening ischemia. From July 2003 to December 2007, 60 consecutive diabetic patients (M/F = 41/19; mean age, 69.4 {+-} 9.4 years) with Fontaine stage IV critical limb ischemia, not suitable for surgical recanalization, underwent primary infrainguinal subintimal angioplasty. The technical success, perioperative morbidity and mortality, and clinical success (defined by ulcer healing) were evaluated. Kaplan-Meier life-table analysis was obtained for cumulative clinical success, limb salvage, and survival rates. The procedure was technically successful in 55 of 60 (91.7%) patients; in 5 cases we were not able to achieve a reentry. Periprocedural mortality was 5% (3 patients); three patients (5%) required major amputation periprocedurally. Mean follow-up was 23 months (range, 0-48 months). On an intention-to-treat basis, the limb salvage rate was 93.3% (56/60 patients); ulcer healing was observed in 45 of 60 (75%) patients and it was significantly (p < 0.05) associated with serum creatinine and HbA1c levels, diabetes duration, and infrapopliteal recanalization. One- and three-year cumulative survival rates were 91.5% and 83.1%, respectively; serum creatinine levels, patient age, and clinical success were significant predictors of survival. In conclusion, infrainguinal primary subintimal angioplasty is a safe and effective treatment in diabetic patients with limb-threatening ischemia not suitable for surgical recanalization. This procedure is aimed to create a 'temporary bypass' that facilitates ulcer healing.

  14. Transhepatic Venous Approach for Balloon-assisted Cervical Collateral Venous Access

    SciTech Connect

    Eyheremendy, Eduardo P.; Malizia, Patricio; Sierre, Sergio

    2011-12-15

    Central venous catheter placement is indicated in many situations, and an increasing number of patients require temporary and long-term central catheters. Frequently, patients who have undergone multiple central veins catheterizations develop complete and diffuse venous occlusion, and this constitutes a difficult-to-manage clinical problem. We report a case of a 20-year-old patient who was referred to our department for central venous line placement who manifested bilateral femoral, jugular, and subclavian veins occlusion. A central venous catheter was implanted through a cervical collateral vein, targeting on and puncturing an angioplasty balloon, and advanced into the collateral vein through a transhepatic venous access.

  15. Dilatation balloons: polymer selection, balloon design and assembly.

    PubMed

    Crittenden, J F

    1987-01-01

    The current status of coronary dilating instruments is presented from the designer's perspective. Catheter shaft design is considered by important features, common catheter materials and types of catheter construction. Among the seven companies manufacturing balloon dilating instruments, only three types of catheter and four materials are offered. Balloon design is presented by important features and by materials selected. Performance comparisons are made between the three materials used to fabricate dilating balloons: PVC, PE and PET.

  16. Vega balloon meteorological measurements

    NASA Technical Reports Server (NTRS)

    Crisp, D.; Ingersoll, A. P.; Hildebrand, C. E.; Preston, R. A.

    1990-01-01

    The Vega balloons obtained in situ measurements of pressure, temperature, vertical winds, cloud density, ambient illumination, and the frequency of lightning during their flights in the Venus middle cloud layer. The Vega measurements were used to develop a comprehensive description of the meteorology of the Venus middle cloud layer. The Vega measurements provide the following picture: large horizontal temperature gradients near the equator, vigorous convection, and weather conditions that can change dramatically on time scales as short as one hour.

  17. NASA Super Pressure Balloon

    NASA Technical Reports Server (NTRS)

    Fairbrother, Debbie

    2016-01-01

    NASA is in the process of qualifying the mid-size Super Pressure Balloon (SPB) to provide constant density altitude flight for science investigations at polar and mid-latitudes. The status of the development of the 18.8 million cubic foot SPB capable of carrying one-tonne of science to 110,000 feet, will be given. In addition, the operating considerations such as launch sites, flight safety considerations, and recovery will be discussed.

  18. Space Weather Ballooning

    NASA Astrophysics Data System (ADS)

    Phillips, Tony; Johnson, Sam; Koske-Phillips, Amelia; White, Michael; Yarborough, Amelia; Lamb, Aaron; Herbst, Anna; Molina, Ferris; Gilpin, Justin; Grah, Olivia; Perez, Ginger; Reid, Carson; Harvey, Joey; Schultz, Jamie

    2016-10-01

    We have developed a "Space Weather Buoy" for measuring upper atmospheric radiation from cosmic rays and solar storms. The Buoy, which is carried to the stratosphere by helium balloons, is relatively inexpensive and uses off-the-shelf technology accessible to small colleges and high schools. Using this device, we have measured two Forbush Decreases and a small surge in atmospheric radiation during the St. Patrick's Day geomagnetic storm of March 2015.

  19. Quantitative angiography during coronary angioplasty with a single angiographic view: a comparison of automated edge detection and videodensitometric techniques.

    PubMed

    Escaned, J; Foley, D P; Haase, J; Di Mario, C; Hermans, W R; de Feyter, P J; Serruys, P W

    1993-12-01

    Little information is available on the reliability of coronary luminal measurements obtained from quantitative analysis of a single angiographic view, an approach that is central to the practical use of on-line quantitative angiography. In the present study we investigated the contribution of two different techniques of quantitative angiography, edge detection (ED) and videodensitometry (VD), to the application of this concept during coronary angioplasty. Forty-six balloon angioplasty procedures were included in this study, all of them performed in a stenosis located in the mid right coronary segment. This coronary location was chosen to optimize data collection on luminal morphology and to minimize the number of factors that may adversely affect quantitative analysis with both techniques. In all cases two orthogonal angiographic projections were obtained before, after balloon dilatation, and at follow-up. Correlation coefficients and differences between orthogonal measurements obtained with each technique were used to evaluate the agreement between orthogonal readings at every stage of the procedure. The obtained correlation coefficients and mean differences (MD) between orthogonal measurements were as follows: before percutaneous transluminal coronary angiography (PTCA), 0.67 (MD 0.01 +/- 0.47 mm2) and 0.57 (MD 0.05 +/- 0.64 mm2) for ED and VD, respectively (Pitman's test for SD, p < 0.05); after balloon dilatation, 0.32 (MD -0.56 +/- 1.53 mm2) and 0.53 (MD -0.15 +/- 1.43 mm2) for ED and VD, respectively (paired t test for MD, p < 0.05); and at follow-up 0.79 (MD -0.15 +/- 0.97 mm2) and 0.73 (MD 0.17 +/- 1.16 mm2) for ED and VD, respectively (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Adjunct Info: A Journal for Managers of Adjunct and Part-Time Faculty, 1994-97.

    ERIC Educational Resources Information Center

    Greive, Donald, Ed.

    1997-01-01

    This document consists of the twelve issues of the quarterly journal "Adjunct Info" during the three-year period 1994-1997. Individual issues contain articles, editorials, columns, teaching tips, and suggested resources related to management of adjunct and part-time faculty. Major articles include: "A Message to Managers: From an Adjunct" (June…

  1. Prevention of Intracranial In-stent Restenoses: Predilatation with a Drug Eluting Balloon, Followed by the Deployment of a Self-Expanding Stent

    SciTech Connect

    Vajda, Zsolt Guethe, Thomas Perez, Marta Aguilar Kurre, Wiebke; Schmid, Elisabeth Baezner, Hansjoerg; Henkes, Hans

    2013-04-15

    Stenting in intracranial atherosclerotic disease (ICAD) is increasingly debated, due to issues of procedural safety, technical efficacy, and in-stent recurrent stenoses (ISR). In the present study, feasibility, safety, and efficacy of angioplasty using a drug-eluting balloon (DEB) followed by the implantation of a self-expanding stent (Enterprise) were evaluated for the treatment of ICAD lesions. Fifty-two patients (median age: 71 years; range: 54-86 years; male/female ratio 37:15) underwent stenting of high-grade ICAD lesions between February 2010 and November 2011 in a single center. Angioplasty using a paclitaxel coated SeQuent Please (B. Braun, Germany) or DIOR (Eurocor, Germany) coronary PTCA balloon, followed by the implantation of a self-expanding stent (Enterprise, Codman, USA) was performed in 54 lesions. Angiographic and clinical follow-up was performed at 6 and 12 weeks, 6 and 12 months, and yearly thereafter. Technical success rate, periprocedural complications, occurrence of recurrent ischemic symptoms, and the development of an ISR were analyzed. Angioplasty using a DEB followed by stent implantation was successfully performed in 44 (81 %) cases. DEB insertion failed in 19 % of the cases and angioplasty was finally performed using a conventional PTCA balloon. The combined procedure related permanent neurologic morbidity and mortality rate (stroke, ICH, and subarachnoid hemorrhage) at 30 days and beyond was 5 %. Angiographic and clinical follow-up were obtained in 33 (61 %) lesions in 32 patients. Recurrent stenosis was seen in one (3 %) lesion. Angioplasty and stenting using a DEB is safe and yields encouragingly low ISR rates. Further technical developments to improve lesion accessibility are, nevertheless, mandatory.

  2. Development of novel short-term heating angioplasty: thermal denaturation dynamics of collagen in artery wall

    NASA Astrophysics Data System (ADS)

    Shimazaki, N.; Tokunaga, H.; Katou, Y.; Hayashi, T.; Arai, T.

    2009-02-01

    We have studied to develop the new thermal angioplasty methodology, photo-thermo dynamic balloon angioplasty (PTDBA), which provides artery dilatation with short-term (<15s) and uniform heating through the balloon by the combination of the efficient laser driven heat generation and fluid perfusion. Thermal denaturation degree of the collagen in artery media may be the important factor to attain sufficient artery dilatation for the PTDBA. In order to predict the optimum heating condition i.e. the balloon temperature and heating duration, we investigated the thermal denaturation dynamics of artery collagen in ex vivo. The extracted fresh porcine carotid artery was used. The temperature-dependent light scattering property and mechanical property of the artery specimen were simultaneously measured during artery temperature rising by specially made setup to assess the denaturation of arterial collagen. The change rate of the backscattered light intensity from the artery specimen; I(T)/I0 with 633nm was measured to evaluate the artery scattering property change with the thermal denaturation. The artery specimen was heated from 25°C to 80°C with constant temperature rising rate of 3°C/min. The measured I(T)/I0 was suddenly increased over 48°C. This boundary temperature might be the initiation temperature of the arterial collagen denaturation. We defined the variation of the I(T)/I0 as the collagen denaturation ratio, and calculated the reactive enthalpy by the chemical equilibrium theory. Since the calculated enthalpy was similar to the enthalpy in literature report, the variety of I(T)/I0 during the temperature rising might be attributed to the collagen conformational change due to the denaturation. In terms of the artery internal force measurement, the artery force was decreased with increasing of the artery temperature up to 65°C (i.e. softening), and increased over 65°C (i.e. shrinkage). We confirmed that the changes of the backscattered light (at 633nm in

  3. Optimum designs for superpressure balloons

    NASA Astrophysics Data System (ADS)

    Smith, M. S.; Rainwater, E. L.

    2004-01-01

    The elastica shape is now well known to be the best basic shape for superpressure balloon design. This shape, also known as the pumpkin, or natural shape for balloons, has been well understood since the early 1900s when it was applied to the determination of the shape of descending parachutes. The elastica shape was also investigated in the 1950s when high strength films were used to produce superpressure cylinder balloons. The need for uniform stress distribution in shells of early superpressure balloons led to a long period of the development of spherical superpressure balloons. Not until the late 1970s was the elastica shape revisited for the purpose of the producing superpressure balloons. This paper will review various development efforts in the field of superpressure design and will elaborate on the current state-of-the-art with suggestions for future developments.

  4. Breakthrough in Mars balloon technology

    NASA Astrophysics Data System (ADS)

    Kerzhanovich, V. V.; Cutts, J. A.; Cooper, H. W.; Hall, J. L.; McDonald, B. A.; Pauken, M. T.; White, C. V.; Yavrouian, A. H.; Castano, A.; Cathey, H. M.; Fairbrother, D. A.; Smith, I. S.; Shreves, C. M.; Lachenmeier, T.; Rainwater, E.; Smith, M.

    2004-01-01

    Two prototypes of Mars superpressure balloons were flight tested for aerial deployment and inflation in the Earth's stratosphere in June, 2002. One was an 11.3 m diameter by 6.8 m high pumpkin balloon constructed from polyethylene film and Zylon (PBO) tendons, the second was a 10 m diameter spherical balloon constructed from 12 μm thick Mylar film. Aerial deployment and inflation occurred under parachute descent at 34 km altitude, mimicing the dynamic pressure environment expected during an actual Mars balloon mission. Two on-board video cameras were used on each flight to provide real-time upward and downward views of the flight train. Atmospheric pressure and temperature were also recorded. Both prototypes successfully deployed from their storage container during parachute descent at approximately 40 m/s. The pumpkin balloon also successfully inflated with a 440 g charge of helium gas injected over a 1.5-min period. Since the helium inflation system was deliberately retained after inflation in this test, the pumpkin balloon continued to fall to the ocean where it was recovered for post-flight analysis. The less robust spherical balloon achieved only a partial (~70%) inflation before a structural failure occurred in the balloon film resulting in the loss of the vehicle. This structural failure was diagnosed to result from the vigorous oscillatory motion of the partially inflated balloon, possibly compounded by contact between the balloon film and an instrumentation box above it on the flight train. These two flights together represent significant progress in the development of Mars superpressure balloon technology and pave the way for future flight tests that will include post-deployment flight of the prototype balloons at a stable altitude.

  5. Cleft formation in pumpkin balloons

    NASA Astrophysics Data System (ADS)

    Baginski, Frank E.; Brakke, Kenneth A.; Schur, Willi W.

    NASA’s development of a large payload, high altitude, long duration balloon, the Ultra Long Duration Balloon, centers on a pumpkin shape super-pressure design. Under certain circumstances, it has been observed that a pumpkin balloon may be unable to pressurize into the desired cyclically symmetric equilibrium configuration, settling into a distorted, undesired state instead. Success of the pumpkin balloon for NASA requires a thorough understanding of the phenomenon of multiple stable equilibria and developing of means for the quantitative assessment of design measures that prevent the occurrence of undesired equilibrium. In this paper, we will use the concept of stability to classify cyclically symmetric equilibrium states at full inflation and pressurization. Our mathematical model for a strained equilibrium balloon, when applied to a shape that mimics the Phase IV-A balloon of Flight 517, predicts instability at float. Launched in Spring 2003, this pumpkin balloon failed to deploy properly. Observations on pumpkin shape type super-pressure balloons that date back to the 1980s suggest that within a narrowly defined design class of pumpkin shape super-pressure balloons where individual designs are fully described by the number of gores ng and by a single measure of the bulging gore shape, the designs tend to become more vulnerable with the growing number of gores and with the diminishing size of the bulge radius rB Weight efficiency considerations favor a small bulge radius, while robust deployment into the desired cyclically symmetrical configuration becomes more likely with an increased bulge radius. In an effort to quantify this dependency, we will explore the stability of a family of balloon shapes parametrized by (ng, rB) which includes a design that is very similar, but not identical, to the balloon of Flight 517. In addition, we carry out a number of simulations that demonstrate other aspects related to multiple equilibria of pumpkin balloons.

  6. In-vivo holmium laser angioplasty

    NASA Astrophysics Data System (ADS)

    Haase, Karl K.; Hassenstein, Stefan; Hanke, Hartmut; Hanke, Sybille; Oberhoff, Martin; Karsch, Karl R.

    1992-08-01

    Holmium laser angioplasty was performed in the atheromatous carotid artery of 10 rabbits to evaluate this mid-infrared laser as an alternative energy source for angioplasty. An additional 10 rabbits served as a control group. The laser emitted light at a wavelength of 2120 nm with pulse durations of 150 microsecond(s) . The energy density was 17.5 J/cm2. Cross sections were analyzed in regard to laser specific injury 7 and 14 days following laser irradiation. Staining of (alpha) -actin was used to identify smooth muscle cells (SMC), and bromodesoxyuridine labeling was carried out to determine the extent of proliferating cells. Integrity of the lamina elastica interna fibers was disrupted in 6 of 10 animals. In all animals, loss of medial SMCs was observed 7 and 14 days after treatment. Quantification of SMCs undergoing DNA synthesis in the intima and media showed a significant increase of labelled cells following laser irradiation. This proliferative response resulted in a significant increase of intimal thickening after laser ablation.

  7. Outpatient coronary angioplasty: feasible and safe.

    PubMed

    Slagboom, Ton; Kiemeneij, Ferdinand; Laarman, Gert Jan; van der Wieken, Ron

    2005-04-01

    This study tested the safety and feasibility of coronary angioplasty on an outpatient basis. The purpose of this approach includes cost-effectiveness and patient comfort. Six hundred forty-four patients were randomized to either transradial or transfemoral PTCA using 6 Fr equipment. Patients were triaged to outpatient management based on a predefined set of predictors of an adverse outcome in the first 24 hr after initially successful coronary angioplasty. Three hundred seventy-five patients (58%) were discharged 4-6 hr after PTCA; 42% stayed in hospital overnight. In the outpatient group, one adverse event occurred (subacute stent thrombosis 7 hr postdischarge, nonfatal myocardial infarction). There were no major vascular complications. In the hospital group, 19 patients (7%) sustained an adverse cardiac even in the first 24 hr; 1 patient died. Patients treated via the femoral route had more (minor) bleeding complications (19 patients; 6%); in 17 of these, this was the sole reason that discharge was delayed. PTCA on an outpatient basis, performed via the radial or the femoral artery with low-profile equipment, is safe and feasible in a considerable part of a routine PTCA population. A larger proportion of transradial patients can be discharged due to a reduction in (minor) bleeding complications.

  8. Magnetic Particle / Magnetic Resonance Imaging: In-Vitro MPI-Guided Real Time Catheter Tracking and 4D Angioplasty Using a Road Map and Blood Pool Tracer Approach

    PubMed Central

    Jung, Caroline; Kaul, Michael Gerhard; Werner, Franziska; Them, Kolja; Reimer, Rudolph; Nielsen, Peter; vom Scheidt, Annika; Adam, Gerhard; Knopp, Tobias; Ittrich, Harald

    2016-01-01

    Purpose In-vitro evaluation of the feasibility of 4D real time tracking of endovascular devices and stenosis treatment with a magnetic particle imaging (MPI) / magnetic resonance imaging (MRI) road map approach and an MPI-guided approach using a blood pool tracer. Materials and Methods A guide wire and angioplasty-catheter were labeled with a thin layer of magnetic lacquer. For real time MPI a custom made software framework was developed. A stenotic vessel phantom filled with saline or superparamagnetic iron oxide nanoparticles (MM4) was equipped with bimodal fiducial markers for co-registration in preclinical 7T MRI and MPI. In-vitro angioplasty was performed inflating the balloon with saline or MM4. MPI data were acquired using a field of view of 37.3×37.3×18.6 mm3 and a frame rate of 46 volumes/sec. Analysis of the magnetic lacquer-marks on the devices were performed with electron microscopy, atomic absorption spectrometry and micro-computed tomography. Results Magnetic marks allowed for MPI/MRI guidance of interventional devices. Bimodal fiducial markers enable MPI/MRI image fusion for MRI based roadmapping. MRI roadmapping and the blood pool tracer approach facilitate MPI real time monitoring of in-vitro angioplasty. Successful angioplasty was verified with MPI and MRI. Magnetic marks consist of micrometer sized ferromagnetic plates mainly composed of iron and iron oxide. Conclusions 4D real time MP imaging, tracking and guiding of endovascular instruments and in-vitro angioplasty is feasible. In addition to an approach that requires a blood pool tracer, MRI based roadmapping might emerge as a promising tool for radiation free 4D MPI-guided interventions. PMID:27249022

  9. Use of Rhenium-188 Liquid-Filled Balloons for Inhibition of Coronary Restenosis After PTCA - A New Opportunity for Nuclear Medicine

    SciTech Connect

    Knapp, F.F., Jr.; Spencer, R.H.; Stabin, M.

    1999-05-13

    Although the use of ionizing radiation for the treatment of benign lesions such as keloids has been available for nearly one hundred years, only recently have the cost effective benefits of such technology for the inhibition of arterial restenosis following controlled vessel damage from balloon angioplasty been fully realized. In particular, the use of balloons filled with solutions of beta-emitting radioisotopes for vessel irradiation provide the benefit of uniform vessel irradiation. Use of such contained ("unsealed") sources is expected to represent a new opportunity for nuclear medicine physicians working in conjunction with interventional cardiologists to provide this new approach for restenosis therapy.

  10. Application of new balloon catheters in the treatment of congenital heart defects

    PubMed Central

    Fiszer, Roland; Szkutnik, Małgorzata; Smerdziński, Sebastian; Chodór, Beata; Białkowski, Jacek

    2016-01-01

    Introduction Balloon angioplasty (BAP) and aortic or pulmonary balloon valvuloplasty (BAV, BPV) are well-established treatment options in congenital heart defects. Recently, significant technological progress has been made and new catheters have been implemented in clinical practice. Aim To analyze the results of BAP, BAV and BPV with the new balloon catheter Valver and its second generation Valver II, which the company Balton (Poland) launched and developed. These catheters have not been clinically evaluated yet. Material and methods We performed 64 interventions with Valver I and Valver II. With Valver I the following procedures were performed: 17 BPV (including 9 in tetralogy of Fallot – TOF), 10 BAV and 27 BAP in coarctations of the aorta (CoA) – including 9 native and 18 after surgery. With Valver II ten interventions were done – 3 BPV, 2 pulmonary supravalvular BAP (after switch operations), 2 BAP of recoarctations and 3 other BAP. Age of the patients ranged from a few days to 40 years. Results All procedures were completed successfully, without rupture of any balloon catheters. The pressure gradient drop was statistically significant in all groups: BPV in isolated pulmonary valvular stenosis 28.1 mm Hg (mean), BPV in TOF 18.7 mm Hg, BAV 32.8 mm Hg, BAP in native CoA 15.4 mm Hg and in recoarctations 18.6 mm Hg. In 3 cases during rapid deflation of Valver I, wrinkles of the balloons made it impossible to insert the whole balloon into the vascular sheath (all were removed surgically from the groin). No such complication occured with Valver II. Conclusions Valver balloon catheters are an effective treatment modality in different valvular and vascular stenoses. PMID:27625686

  11. Venous Recanalization by Metallic Stents After Failure of Balloon Angioplasty or Surgery: Four-Year Experience

    SciTech Connect

    Nazarian, Gwen K.; Austin, William R.; Wegryn, Scott A.; Bjarnason, Haraldur; Stackhouse, Daniel J.; Castaneda-Zuniga, Wilfrido R.; Hunter, David W.

    1996-04-15

    Purpose: This retrospective study describes our updated experience in treating venous stenoses and occlusions with metallic endovascular stents. Methods: Gianturco, Palmaz, and Wallstent stents were placed in 55 patients over a 4-year period. Stent sites included the subclavian veins (9), innominate veins (3), superior vena cava (4), inferior vena cava (3), iliac veins (29), femoral veins (5), and portal veins (6). The most common indications for stent placement were malignant stenoses and chronic pelvic venous occlusions. Venoplasty and/or urokinase were used as ancillary therapy. Patients were anticoagulated for 3-6 months. Follow-up included clinical assessment and duplex ultrasound. Results: Lifetable analysis shows 59%, 63%, and 72% primary, primary assisted, and secondary 1-year patency rates, respectively. The 4-year primary patency rates were the same. Duration of patency depended on the venous site. Death was a complication of stent placement in 2 patients and 12 patients died within 6 months after stent placement from primary disease progression. Although early failures were more common in stents placed across occlusions than stenoses, 1-year secondary patency rates were comparable. Primary patency rates were only slightly lower in patients with malignant obstruction than in patients with benign disease. Conclusion: Endovascular stent placement provides a nonsurgical alternative for reestablishment of venous flow and symptomatic relief in patients with benign as well as malignant venous obstruction.

  12. Mounting of MEMS pressure sensors on catheter guide wires used in balloon angioplasty

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Anandaroop; Sorrell, J.

    2003-07-01

    This paper discusses a potential solution by mounting micro sensors on the tip of a 0.0018" catheter guidewire that can measure local fluid properties, such as pressure, pressure gradient, temperature, and species concentration levels. A design for mounting the sensors on the guidewire tip is proposed. The technique involves etching of picket shaped cavities on the silicon chip carrier. The MEMS sensor is then flip-chip bonded on to the silicon carrier. The design is biologically compatible, minimizing the exposure of potentially hazardous materials to the arterial system. Further, electrical and mechanical connections are robust, while the profile remains within the 0.018" outside diameter of the guide-wire. Basic design for manufacturability issues such as, materials constraints, minimization of parts and working surfaces, providing nesting features, and modular design have been addressed while arriving at the final design. The focus of the current paper is on pressure sensors but the design is generic and should be applicable for the other types of sensors also.

  13. [Reintervention with percutaneous balloon angioplasty in patients with congenital heart disease with left-sided obstructions].

    PubMed

    Márquez-González, Horacio; López-Gallegos, Diana; Pérez-Velázquez, Nataly Alejandra; Yáñez-Gutiérrez, Lucelli

    2017-01-01

    Introducción: las obstrucciones izquierdas representan 15% de las cardiopatías congénitas (CC). El tratamiento en la edad adulta es quirúrgico; no obstante, la dilatación con balón puede paliar los síntomas en edad pediátrica para permitir que alcancen la talla diana. El objetivo fue determinar la sobrevida y los factores asociados a la reintervención en enfermos con CC con obstrucción izquierda tratados con plastía con balón. Métodos: se realizó un estudio de cohorte en pacientes entre 4 y 17 años con cardiopatías de obstrucción izquierda (estenosis valvular, supravalvular y coartación aórtica) tratados con angioplastía con balón exitosa. El seguimiento fue de 10 años y la variable de desenlace fue la reestenosis con criterios para reintervención. Se consideraron variables pronósticas la etapa pediátrica al momento del procedimiento, el estado nutricional, el gradiente residual y la presencia de síndromes genéticos. Se usaron medidas de tendencia central y dispersión. Se usó chi cuadrada en variables cualitativas y Kruskal-Wallis en variables cuantitativas. Resultados: fueron 110 pacientes; 40% presentó coartación aórtica, 35% estenosis valvular y 25% estenosis supravalvular aórtica. El 39% requirió reintervención y la frecuencia fue la siguiente: 80% en estenosis supravalvular, 35% en coartación aórtica y 14% en estenosis valvular aórtica. Conclusión: la intervención con balón es una medida paliativa que permite a los enfermos con obstrucciones izquierdas alcanzar la talla diana.

  14. Primary coronary angioplasty in patients with acute myocardial infarction.

    PubMed Central

    Popma, J J; Chuang, Y C; Satler, L F; Kleiber, B; Leon, M B

    1994-01-01

    In some patients with acute myocardial infarction, thrombolytic therapy may be limited by its failure to reperfuse the occluded artery, by recurrent ischemia (despite initially successful reperfusion), and by major hemorrhagic complications. Primary coronary angioplasty may circumvent these limitations. This article reviews the results of primary angioplasty reported in patients with myocardial infarction and makes recommendations for its use. The review includes pertinent articles found in the English language literature from July 1987 to July 1993 on MEDLINE. Nonrandomized series of primary angioplasty in acute myocardial infarction have demonstrated high procedural success rates (86% to 99%) and infrequent recurrent ischemia (4%). Two randomized trials comparing primary angioplasty and thrombolytic therapy have shown that primary angioplasty results in lower mortality, less recurrent ischemia, shorter length of hospital stay, and improved left ventricular function. Two other randomized studies have shown little benefit from primary angioplasty on myocardial salvage, recurrent ischemia, or ventricular function. One major limitation of primary angioplasty is that it requires 24-hour availability of a catheterization laboratory and experienced surgical personnel. Primary angioplasty may be the preferred approach in patients with extensive myocardial infarction who have immediate (< 120 min) access to a cardiac catheterization laboratory with experienced personnel. Patients having 1) contraindications to thrombolytic therapy, 2) cardiogenic shock, 3) prior coronary bypass surgery, or 4) "stuttering" onset of pain may also benefit from primary angioplasty. Poor candidates for this procedure are those with a small myocardial infarction, those in whom undue delays in access to a cardiac catheterization facility would be expected, or those with complex coronary anatomy, including left main coronary artery disease. PMID:8061539

  15. Use of the AngioSculpt scoring balloon for infrapopliteal lesions in patients with critical limb ischemia: 1-year outcome.

    PubMed

    Bosiers, Marc; Deloose, Koen; Cagiannos, Catherine; Verbist, Jürgen; Peeters, Patrick

    2009-01-01

    The AngioSculpt Scoring Balloon Catheter (AngioScore, Inc., Fremont, CA) is composed of a semicompliant balloon encircled by three nitinol spiral struts providing targeted lesion scoring on balloon inflation. Between April 2005 and April 2006, procedural and follow-up data on 31 patients (mean age 76 years; 54.8% males) endovascularly treated for severe infrapopliteal disease were collected. The AngioSculpt catheter was used to treat 36 complex, tibioperoneal, atherosclerotic lesions. All patients had symptomatic critical limb ischemia (Rutherford 4-5) and single-vessel runoff to the ankle. Complication-free survival at 1 month was the safety end point, whereas primary patency and limb salvage were the efficacy end points evaluated at 1 year. The AngioSculpt balloon was successfully inflated in all 36 target lesions. Eleven patients (35.5%) required additional stenting for minor dissections or suboptimal stenosis reduction. The 1-month complication-free survival was 96.8%. One-year survival, primary patency, and limb salvage rates were 83.9 +/- 6.6%, 61.0 +/- 9.3%, and 86.3 +/- 6.4%, respectively. The 1-year data show the AngioSculpt Scoring Balloon Catheter to be an effective and safe treatment for infrapopliteal, atherosclerotic lesions in patients with critical limb ischemia. However, more patients, a longer follow-up, and randomized studies comparing it with conventional balloon angioplasty and stenting in the infrapopliteal region are required.

  16. Telescope Systems for Balloon-Borne Research

    NASA Technical Reports Server (NTRS)

    Swift, C. (Editor); Witteborn, F. C. (Editor); Shipley, A. (Editor)

    1974-01-01

    The proceedings of a conference on the use of balloons for scientific research are presented. The subjects discussed include the following: (1) astronomical observations with balloon-borne telescopes, (2) orientable, stabilized balloon-borne gondola for around-the-world flights, (3) ultraviolet stellar spectrophotometry from a balloon platform, (4) infrared telescope for balloon-borne infrared astronomy, and (5) stabilization, pointing, and command control of balloon-borne telescopes.

  17. Clopidogrel Responsiveness in Patients Undergoing Peripheral Angioplasty

    SciTech Connect

    Pastromas, Georgios Spiliopoulos, Stavros Katsanos, Konstantinos Diamantopoulos, Athanasios Kitrou, Panagiotis Karnabatidis, Dimitrios Siablis, Dimitrios

    2013-12-15

    Purpose: To investigate the incidence and clinical significance of platelet responsiveness in patients receiving clopidogrel after peripheral angioplasty procedures. Materials and Methods: This prospective study included patients receiving antiplatelet therapy with clopidogrel 75 mg after infrainguinal angioplasty or stenting and who presented to our department during routine follow-up. Clopidogrel responsiveness was tested using the VerifyNow P2Y12 Assay. Patients with residual platelet reactivity units (PRU) {>=} 235 were considered as nonresponders (NR group NR), whereas patients with PRU < 235 were considered as normal (responders [group R]). Primary end points were incidence of resistance to clopidogrel and target limb reintervention (TLR)-free survival, whereas secondary end points included limb salvage rates and the identification of any independent predictors influencing clinical outcomes. Results: In total, 113 consecutive patients (mean age 69 {+-} 8 years) with 139 limbs were enrolled. After clopidogrel responsiveness analysis, 61 patients (53.9 %) with 73 limbs (52.5 %) were assigned to group R and 52 patients (46.1 %) with 66 limbs (47.5 %) to group NR. Mean follow-up interval was 27.7 {+-} 22.9 months (range 3-95). Diabetes mellitus, critical limb ischemia, and renal disease were associated with clopidogrel resistance (Fisher's exact test; p < 0.05). According to Kaplan-Meier analysis, TLR-free survival was significantly superior in group R compared with group NR (20.7 vs. 1.9 %, respectively, at 7-year follow-up; p = 0.001), whereas resistance to clopidogrel was identified as the only independent predictor of decreased TLR-free survival (hazard rate 0.536, 95 % confidence interval 0.31-0.90; p = 0.01). Cumulative TLR rate was significantly increased in group NR compared with group R (71.2 % [52 of 73] vs. 31.8 % [21 of 66], respectively; p < 0.001). Limb salvage was similar in both groups. Conclusion: Clopidogrel resistance was related with

  18. Aerodynamics of a Party Balloon

    ERIC Educational Resources Information Center

    Cross, Rod

    2007-01-01

    It is well-known that a party balloon can be made to fly erratically across a room, but it can also be used for quantitative measurements of other aspects of aerodynamics. Since a balloon is light and has a large surface area, even relatively weak aerodynamic forces can be readily demonstrated or measured in the classroom. Accurate measurements…

  19. A Methane Balloon Inflation Chamber

    ERIC Educational Resources Information Center

    Czerwinski, Curtis J.; Cordes, Tanya J.; Franek, Joe

    2005-01-01

    The various equipments, procedure and hazards in constructing the device for inflating a methane balloon using a standard methane outlet in a laboratory are described. This device is fast, safe, inexpensive, and easy to use as compared to a hydrogen gas cylinder for inflating balloons.

  20. Scientific Balloons for Venus Exploration

    NASA Astrophysics Data System (ADS)

    Cutts, James; Yavrouian, Andre; Nott, Julian; Baines, Kevin; Limaye, Sanjay; Wilson, Colin; Kerzhanovich, Viktor; Voss, Paul; Hall, Jeffery

    Almost 30 years ago, two balloons were successfully deployed into the atmosphere of Venus as an element of the VeGa - Venus Halley mission conducted by the Soviet Union. As interest in further Venus exploration grows among the established planetary exploration agencies - in Europe, Japan, Russia and the United States, use of balloons is emerging as an essential part of that investigative program. Venus balloons have been proposed in NASA’s Discovery program and ESA’s cosmic vision program and are a key element in NASA’s strategic plan for Venus exploration. At JPL, the focus for the last decade has been on the development of a 7m diameter superpressure pressure(twice that of VeGa) capable of carrying a 100 kg payload (14 times that of VeGA balloons), operating for more than 30 days (15 times the 2 day flight duration of the VeGa balloons) and transmitting up to 20 Mbit of data (300 times that of VeGa balloons). This new generation of balloons must tolerate day night transitions on Venus as well as extended exposure to the sulfuric acid environment. These constant altitude balloons operating at an altitude of about 55 km on Venus where temperatures are benign can also deploy sondes to sound the atmosphere beneath the probe and deliver deep sondes equipped to survive and operate down to the surface. The technology for these balloons is now maturing rapidly and we are now looking forward to the prospects for altitude control balloons that can cycle repeatedly through the Venus cloud region. One concept, which has been used for tropospheric profiling in Antarctica, is the pumped-helium balloon, with heritage to the anchor balloon, and would be best adapted for flight above the 55 km level. Phase change balloons, which use the atmosphere as a heat engine, can be used to investigate the lower cloud region down to 30 km. Progress in components for high temperature operation may also enable investigation of the deep atmosphere of Venus with metal-based balloons.

  1. Nationwide Eclipse Ballooning Project

    NASA Astrophysics Data System (ADS)

    Colman Des Jardins, Angela; Berk Knighton, W.; Larimer, Randal; Mayer-Gawlik, Shane; Fowler, Jennifer; Harmon, Christina; Koehler, Christopher; Guzik, Gregory; Flaten, James; Nolby, Caitlin; Granger, Douglas; Stewart, Michael

    2016-05-01

    The purpose of the Nationwide Eclipse Ballooning Project is to make the most of the 2017 rare eclipse event in four main areas: public engagement, workforce development, partnership development, and science. The Project is focused on two efforts, both student-led: online live video of the eclipse from the edge of space and the study of the atmospheric response to the eclipse. These efforts, however, involving more than 60 teams across the US, are challenging in many ways. Therefore, the Project is leveraging the NASA Space Grant and NOAA atmospheric science communities to make it a success. The first and primary topic of this poster is the NASA Space Grant supported online live video effort. College and high school students on 48 teams from 31 states will conduct high altitude balloon flights from 15-20 locations across the 8/21/2017 total eclipse path, sending live video and images from near space to a national website. Video and images of a total solar eclipse from near space are fascinating and rare. It’s never been done live and certainly not in a network of coverage across a continent. In addition to the live video to the web, these teams are engaged in several other science experiments as secondary payloads. We also briefly highlight the eclipse atmospheric science effort, where about a dozen teams will launch over one hundred radiosondes from across the 2017 path, recording an unprecedented atmospheric data sample. Collected data will include temperature, density, wind, humidity, and ozone measurements.

  2. Feasibility of Angioplasty and Stenting for Abdominal Aortic Lesions Adjacent to Previously Stented Visceral Artery Lesions in Patients with Takayasu Arteritis

    SciTech Connect

    Joseph, George George, Paul V.; Pati, Purendra Kumar; Chandy, Sunil Thomas

    2007-04-15

    Two young female patients with Takayasu arteritis presented with symptomatic long-segment abdominal aortic stenosis in the vicinity of previously deployed celiac and renal artery stents that projected markedly into the narrowed aortic lumen. Crushing or distortion of the visceral artery stents during aortic angioplasty was avoided by performing simultaneous or alternating balloon dilatations in the aorta and in the visceral artery stents. Consequently, the visceral artery stents remained patent and shortened longitudinally, allowing unhindered deployment of Wallstents in the adjacent aorta and abolition of a pressure gradient across the aortic lesions. Access to side branches covered by the Wallstent was obtained without difficulty, enabling the performance of balloon dilatation in multiple side branches and ostial stent deployment in a renal artery. These techniques could increase the scope of endovascular therapy in the treatment of patients with Takayasu arteritis.

  3. Mars Balloon Flight Test Results

    NASA Technical Reports Server (NTRS)

    Hall, Jeffery L.; Pauken, Michael T.; Kerzhanovich, Viktor V.; Walsh, Gerald J.; Kulczycki, Eric A.; Fairbrother, Debora; Shreves, Chris; Lachenmeier, Tim

    2009-01-01

    This paper describes a set of four Earth atmosphere flight test experiments on prototype helium superpressure balloons designed for Mars. Three of the experiments explored the problem of aerial deployment and inflation, using the cold, low density environment of the Earth's stratosphere at an altitude of 30-32 km as a proxy for the Martian atmosphere. Auxiliary carrier balloons were used in three of these test flights to lift the Mars balloon prototype and its supporting system from the ground to the stratosphere where the experiment was conducted. In each case, deployment and helium inflation was initiated after starting a parachute descent of the payload at 5 Pa dynamic pressure, thereby mimicking the conditions expected at Mars after atmospheric entry and high speed parachute deceleration. Upward and downward looking video cameras provided real time images from the flights, with additional data provided by onboard temperature, pressure and GPS sensors. One test of a 660 cc pumpkin balloon was highly successful, achieving deployment, inflation and separation of the balloon from the flight train at the end of inflation; however, some damage was incurred on the balloon during this process. Two flight tests of 12 m diameter spherical Mylar balloons were not successful, although some lessons were learned based on the failure analyses. The final flight experiment consisted of a ground-launched 12 m diameter spherical Mylar balloon that ascended to the designed 30.3 km altitude and successfully floated for 9.5 hours through full noontime daylight and into darkness, after which the telemetry system ran out of electrical power and tracking was lost. The altitude excursions for this last flight were +/-75 m peak to peak, indicating that the balloon was essentially leak free and functioning correctly. This provides substantial confidence that this balloon design will fly for days or weeks at Mars if it can be deployed and inflated without damage.

  4. Lentivirus-mediated RNAi knockdown of the gap junction protein, Cx43, attenuates the development of vascular restenosis following balloon injury

    PubMed Central

    HAN, XIAO-JIAN; CHEN, MIN; HONG, TAO; ZHU, LING-YU; HE, DAN; FENG, JIU-GENG; JIANG, LI-PING

    2015-01-01

    Percutaneous coronary intervention [PCI or percutaneous transluminal coronary angioplasty (PTCA)] has been developed into a mature interventional treatment for atherosclerotic cardiovascular disease. However, the long-term therapeutic effect is compromised by the high incidence of vascular restenosis following angioplasty, and the underlying mechanisms of vascular restenosis have not yet been fully elucidated. In the present study, we investigated the role of the gap junction (GJ) protein, connexin 43 (Cx43), in the development of vascular restenosis. To establish vascular restenosis, rat carotid arteries were subjected to balloon angioplasty injury. At 0, 7, 14 and 2 days following balloon injury, the arteries were removed, and the intimal/medial area of the vessels was measured to evaluate the degree of restenosis. We found that the intimal area gradually increased following balloon injury. Intimal hyperplasia and restenosis were particularly evident at 14 and 28 days after injury. In addition, the mRNA and protein expression of Cx43 was temporarily decreased at 7 days, and subsequently increased at 14 and 28 days following balloon injury, as shown by RT-PCR and western blot analysis. To determine the involvement of Cx43 in vascular restenosis, the lentivirus vector expressing shRNA targeting Cx43, Cx43-RNAi-LV, was used to silence Cx43 in the rat carotid arteries. The knockdown of Cx43 effectively attenuated the development of intimal hyperplasia and vascular restenosis following balloon injury. Thus, our data indicate the vital role of the GJ protein, Cx43, in the development of vascular restenosis, and provide new insight into the pathogenesis of vascular reste-nosis. Cx43 may prove to be a novel potential pharmacological target for the prevention of vascular restenosis following PCI. PMID:25625334

  5. Emergency coronary artery bypass surgery for failed percutaneous coronary angioplasty. A 10-year experience.

    PubMed Central

    Craver, J M; Weintraub, W S; Jones, E L; Guyton, R A; Hatcher, C R

    1992-01-01

    Six hundred ninety-nine patients have required emergency coronary artery bypass after failed elective percutaneous coronary angioplasty during the decade September 1980 through December 1990. This represents 4% of 9860 patients having 12,146 elective percutaneous coronary angioplasty procedures during this interval. Emergency coronary artery bypass was required for acute refractory myocardial ischemia in 82%. Hospital mortality rate for all patients was 3.1%; 3.7% in patients with refractory myocardial ischemia but 0.8% in patients without refractory myocardial ischemia, p = 0.08. Postprocedural Q-wave myocardial infarctions were observed in 21% versus 2.4%, p less than 0.0001, and intra-aortic balloon pumping was required in 19% with versus 0.8% without refractory myocardial ischemia, p less than 0.0001. Multivessel disease, p = 0.004, age older than 65 years, p = 0.005, and refractory myocardial ischemia, p = 0.08, interacted to produce the highest risk of in-hospital death. Follow-up shows that there have been 28 additional late deaths, including 23 of cardiac causes for a 91% survival at 5 years. Freedom from both late death and Q-wave myocardial infarction at 5 years was 61%. In the group going to emergency coronary artery bypass with refractory myocardial ischemia, the late cardiac survival was 90%, and in those without ischemia, 92% at 5 years, p = not significant. The MI--free survival in the group with refractory ischemia, however, was 56% versus 83% in the group without ischemia, p less than 0.0001. Multivariate analysis showed the highest late event rates for patients with Q-wave myocardial infarction at the initial emergency coronary artery bypass, age older than 65 years, angina class III or IV, and prior coronary bypass surgery. In spite of a continuing high incidence of early acute myocardial infarction and an increasing operative mortality rate (7%) in the latest 3 years cohort of patients, excellent late survival and low subsequent cardiac event

  6. Bibliotherapy as a Counseling Adjunct: Research Findings.

    ERIC Educational Resources Information Center

    Schrank, Frederick A.; Engels, Dennis W.

    1981-01-01

    Reviews research relating to various aspects of bibliotherapy, including academic achievement, assertiveness, attitude change, behavioral change, fear reduction, helper effectiveness, marital accord, self-development, and therapeutic gains. Discusses implications for using bibliotherapy as an adjunct to counseling. (RC)

  7. An Orientation Program for Clinical Adjunct Faculty.

    PubMed

    Rice, Gwendolyn

    2016-01-01

    Having highly competent clinical faculty in an institution of higher learning is a prerequisite for graduating safe nurses in the future. The purpose of this project was to increase each clinical nurse's knowledge and skills for the new role of clinical adjunct nursing faculty. Successful implementation of this program will help promote consistency in effective job performance of clinical adjunct faculty and facilitate achievement of the projected goals and outcomes. This orientation program was presented in a one day face-to-face encounter with twelve (12) adjunct faculty members, tenured and others on the tenured track. These faculty members were hired by City Colleges of Chicago (CCC) School of Nursing Program at the Malcolm X College. Presentations were given by attendees with a lesson plan. Pre-test, post-test and evaluation forms were presented and it was agreed that an orientation program should be developed and presented to all newly hired clinical adjunct nursing faculty at CCC.

  8. Interventional balloon-enteroscopy.

    PubMed

    Albert, Jörg G

    2012-01-01

    Balloon assisted enteroscopy (BE) expands greatly the therapeutic options in interventional endoscopy; bleeding sites, strictures, polyps, and other small bowel lesions are increasingly been treated by use of BE in the last 10 years. Treatment options for small bowel bleeding include Argon plasma coagulation (APC), injection therapy, and application of TTS metal clips, and thereby bleeding is stopped in most cases. Dilating symptomatic strictures, resecting polyps as seen in Peutz-Jeghers syndrome (PJS), and removing foreign bodies, BE carries most endoscopic treatment techniques to the small bowel. Another new indication field for BE are interventions at the biliary system in patients with surgically modified anatomy such as Roux-Y anastomosis. This review offers a full overview on indications of BE and refers to the practical use of the method for all endoscopic interventions.

  9. Stability of Lobed Balloons

    NASA Technical Reports Server (NTRS)

    Ball, Danny (Technical Monitor); Pagitz, M.; Pellegrino, Xu S.

    2004-01-01

    This paper presents a computational study of the stability of simple lobed balloon structures. Two approaches are presented, one based on a wrinkled material model and one based on a variable Poisson s ratio model that eliminates compressive stresses iteratively. The first approach is used to investigate the stability of both a single isotensoid and a stack of four isotensoids, for perturbations of in.nitesimally small amplitude. It is found that both structures are stable for global deformation modes, but unstable for local modes at su.ciently large pressure. Both structures are stable if an isotropic model is assumed. The second approach is used to investigate the stability of the isotensoid stack for large shape perturbations, taking into account contact between di.erent surfaces. For this structure a distorted, stable configuration is found. It is also found that the volume enclosed by this con.guration is smaller than that enclosed by the undistorted structure.

  10. Air Force Cambridge Research Laboratories balloon operations

    NASA Technical Reports Server (NTRS)

    Danaher, T. J.

    1974-01-01

    The establishment and functions of the AFCRL balloon operations facility are discussed. The types of research work conducted by the facility are defined. The facilities which support the balloon programs are described. The free balloon and tethered balloon capabilities are analyzed.

  11. SAM 2 balloon test (stratospheric aerosol measurement)

    NASA Technical Reports Server (NTRS)

    Pepin, T. J.

    1976-01-01

    As a parallel effort to the LACATE balloon experiment a small optical system was constructed to enable a balloon test of a diode filter system similar to the type planned for the Nimbus-G SAM II experiment. The system was called the SAM II Balloon Test. Results of the balloon flight are summarized.

  12. Structure variations of pumpkin balloon

    NASA Astrophysics Data System (ADS)

    Yajima, N.; Izutsu, N.; Honda, H.

    A robed pumpkin balloon by 3-D gore design concept is recognized as a basic form for a super -pressure balloon. This paper deals with an extension of this design concept for other large pressurized membrane structures, such as a stratospheric airship and a balloon of which volume is controllable. The structural modifications are performed by means of additional ropes or poles. When the original pumpkin shape is modified for those systems, superior characteristics of 3-D gore design, those are large bulges with a small local radius and unidirectional film tension, should be maintained. Improved design methods which are adequate for the above subjects will be discussed in detail.

  13. Percutaneous Transluminal Angioplasty of Hepatic Artery Stenosis in Patients After Orthotopic Liver Transplantation: Mid-term Results

    SciTech Connect

    Jarmila, Lastovickova Jan, Peregrin

    2011-12-15

    Purpose: This study was designed to present our experience with percutaneous treatment of hepatic artery stenosis in orthotopic liver transplant patients and to evaluate the efficacy, technical outcomes, and mid-term clinical results of the procedure. Methods: Twenty-two percutaneous transluminal angioplasties (PTAs) were performed in 19 liver transplant recipients at our institution between 1998 and 2010. Stents were placed into the hepatic/celiac artery in 16 PTAs, but balloon dilatation alone was performed in 6 because of the anatomical condition of the vessel. PTA/stenting was indicated in 17 patients because of elevated liver enzymes; 2 patients were asymptomatic. The objective of treating stenosis was prevention of long-term complications, including thrombosis. Results: Technical success was achieved in all patients. There was only one complication: dissection of the treated artery without any subsequent adverse effects. In all patients, elevated liver enzyme levels improved after treatment. No restenosis was observed in any patient during a mean follow-up of 2.6 years (1 month to 5.5 years). Conclusions: Percutaneous angioplasty/stent placement is a safe method for the treatment of hepatic artery stenosis after orthotopic liver transplantation, with a high technical success rate and promising mid-term results.

  14. Angioplasty of forearm arteries as a finger salvage procedure for patient with end-stage renal failure

    PubMed Central

    Law, Yuk; Chan, Yiu Che; Cheng, Stephen Wing-Keung

    2016-01-01

    Due to the relatively low metabolic demand and extensive collaterals of the upper limb, peripheral arterial disease seldom leads to tissue loss, except in patients with end-stage renal failure (ESRF), rheumatologic diseases, Raynaud’s disease, frostbites, or distal emboli. We report a case of a 51-year-old lady with ESRF who presented to our tertiary referral vascular center with infected gangrene of her right ring finger. Duplex ultrasound showed that her forearm arteries were severely diseased. Digital subtraction angiogram showed severe multilevel stenoses/occlusions in her forearm radial and ulnar arteries. These lesions were successfully angioplastized with 2 mm × 25 mm angioplasty balloon. Completion angiogram showed good radiological results with some post-dilatation spasm which improved with intra-arterial glyceryl trinitrate. The sepsis improved after revascularization, and the distal phalanx was allowed to self-demarcate with dressings and autoamputate with good clinical results. Our case illustrated that even in delayed setting, patients could still benefit from specialist vascular care with a combination of expert care and angioplasty of forearm arteries, with successful salvage of her finger. PMID:27143949

  15. Percutaneous transluminal angioplasty in a patient with chronic cerebrospinal venous insufficiency and persistent left superior vena cava.

    PubMed

    Lupattelli, T; Benassi, F; Righi, E; Bavera, P; Bellagamba, G

    2014-04-01

    Chronic cerebrospinal venous insufficiency (CCSVI) is a syndrome characterized by stenoses of the internal jugular veins (IJVs) and/or azygos veins and formation of collateral venous channels. A case of a 57-year-old patient with CCSVI in whom the venous outflow from the left IJV to the right atrium occurred through a venous anomaly, the persistent left superior vena cava (PLSVC), is reported. PLSVC is caused by persistence of the left anterior cardinal vein that drains blood from the limb effluent from the left and the left side of head and neck into coronary sinus (Type a), or in the left atrium (Type b). PLSVC can be associated either with innominate vein hypoplasia or other congenital heart abnormalities. Because of evidence of left innominate vein hypoplasia, angioplasty was not performed using the ordinary route but passing with the balloon directly through the PLSVC up to the left IJV. Finally, angioplasty was carried out in a standard manner in the right IJV as well as in the azygous vein. Confirmation angiogram revealed complete reopening of all treated vessels with no evidence of peri- and postoperative complications. The patient was discharged home the following day in good general conditions. PLSVC is a rare congenital vein anomaly but in case of concomitant innominate vein hypoplasia may prove to be a valuable alternative to treat patients with IJV diseases.

  16. Development of novel short-term heating angioplasty: diameter and elasticity change of vascular wall ex vivo

    NASA Astrophysics Data System (ADS)

    Shimazaki, Natsumi; Kaneko, Kenji; Nakatani, Eriko; Arai, Tsunenori

    2007-02-01

    In order to investigate the optimum operation parameters on novel short-term heating (<15s, approx. 70 °C) balloon, named Photo-thermo dynamic balloon (PTDB), we studied diameter and elasticity change of vascular wall after dilatation ex vivo. We have been studying to develop the PTDB angioplasty in which we demonstrated sufficient vascular dilatation with lower pressure by heat- induced denaturation of arterial collagen. And we have also demonstrated the suppression of intimal hyperplasia in animal experiments. We need to understand the PTDB dilatation mechanism to determine the optimum operation parameters. The prototype PTDB with diameter of 3mm was used in our experiments. The internal diameters of extracted fresh porcine carotid arteries at pre- and post- PTDB dilatation were measured. Balloon parameters were follows; pressure P=2atm, peak temperature in balloon T=60-80 °C, and heating duration t=4-30s. Morphological change in the media of dilated artery with PTDB were microscopically examined with Weigert staining. Elastic properties were carried out by stress-strain measurements with calculation of young's modulus. We found that PTDB dilatation provided the effect to prevent elastic recoil. We explained that the reason of this effect might be arrangement of micro- structure in the media, i.e., heat-denatured collagen fibers sustained the elastic recoil due to rubbery elastin fibers. The arterial elasticity was not significant different after PTDB dilatation. It was suggested that there could be no compliance mismatch after PTDB dilatation in physiological range. We found that a part of PTDB dilatation mechanism, in which the vascular wall structure played an important role. The optimum operation parameters for PTDB might be determined in consideration of collagen denaturation progress and arterial composition.

  17. Aggressive plaque modification with rotational atherectomy and cutting balloon for optimal stent expansion in calcified lesions

    PubMed Central

    Tang, Zhe; Bai, Jing; Su, Shao-Ping; Lee, Pui-Wai; Peng, Liang; Zhang, Tao; Sun, Ting; Nong, Jing-Guo; Li, Tian-De; Wang, Yu

    2016-01-01

    Objective To evaluate the factors affecting optimal stent expansion in calcified lesions treated by aggressive plaque modification with rotational atherectomy (RA) and a cutting balloon (CB). Methods From January 2014 to May 2015, 92 patients with moderate to severe coronary calcified lesions underwent rotational atherectomy and intravascular ultrasound imaging at Chinese PLA General Hospital (Beijing, China) were included in this study. They were divided into a rotational artherectomy combined with cutting balloon (RACB) group (46 patients treated with RA followed by CB angioplasty) and an RA group (46 patients treated with RA followed by plain balloon angioplasty). Another 40 patients with similar severity of their calcified lesions treated with plain old balloon angioplasty (POBA) were demographically matched to the other groups and defined as the POBA group. All patients received a drug-eluting stent after plaque preparation. Lumen diameter and lumen diameter stenosis (LDS) were measured by quantitative coronary angiography at baseline, after RA, after dilatation, and after stenting. Optimal stent expansion was defined as the final LDS < 10%. Results The initial and post-RA LDS values were similar among the three groups. However, after dilatation, the LDS significantly decreased in the RACB group (from 54.5% ± 8.9% to 36.1% ± 7.1%) but only moderately decreased (from 55.7% ± 7.8% to 46.9% ± 9.4%) in the RA group (time × group, P < 0.001). After stenting, there was a higher rate of optimal stent expansion in the RACB group (71.7% in the RACB group, 54.5% in the RA group, and 15% in the POBA group, P < 0.001), and the final LDS was significantly diminished in the RACB group compared to the other two groups (6.0% ± 2.3%, 10.8% ± 3.3%, 12.7% ± 2.1%, P < 0.001). Moreover, an LDS ≤ 40% after plaque preparation (OR = 2.994, 95% CI: 1.297–6.911) was associated with optimal stent expansion, which also had a positive correlation with the appearance of a

  18. Technical and Clinical Results After Percutaneous Angioplasty in Nonmedial Fibromuscular Dysplasia: Outcome After Endovascular Management of Unifocal Renal Artery Stenoses in 30 Patients

    SciTech Connect

    Barrier, Pierre Julien, Auriol; Guillaume, Canevet; Philippe, Otal; Herve, Rousseau; Francis, Joffre

    2010-04-15

    Although percutaneous transluminal renal angioplasty (PTRA) is associated with excellent results in medial fibromuscular dysplasia (FMD), the clinical and technical outcome in the less common nonmedial subtype of FMD is not clearly known. Angiographic PTRA results and clinical follow-up were documented, to report technical and clinical results in 30 patients with unifocal, nonmedial dysplastic stenoses. Balloon angioplasty was technically successful in only 65% of the lesions. Additional stenting, performed after PTRA failure in six patients, increased the initial technical success rate to 82%. Stenting was used in another lesion after restenosis, and long-term patency was achieved in only three of the seven stented lesions. Frequent restenoses and unusual complications were observed during follow-up. Stent fracture occurred in two cases. Overall, long-term clinical and technical successes were sustained in 70 and 76%, respectively. We conclude that nonmedial, unifocal renal artery dysplastic stenoses do not share the excellent prognosis of the medial type and that stenting should be avoided. Therefore, surgery should be considered in lesions remaining unresponsive to balloon dilatation, after a second PTRA attempt.

  19. High dose rate brachytherapy for prevention of restenosis after percutaneous transluminal coronary angioplasty: Preliminary dosimetric tests of a new source presentation

    SciTech Connect

    Popowski, Y.; Rouzaud, M.; Kurtz, J.M.

    1995-08-30

    Balloon dilatation of coronary artery stenosis has become a standard treatment of atherosclerotic heart disease. Restenosis due to excessive intimal cell proliferation, which subsequently occurs in 20-50% of patients, represents one of the major clinical problems in contemporary cardiology, and no satisfactory method for its prevention has thus far been found. Because modest doses of radiation have proved effective in preventing certain types of abnormal cellular proliferation resulting from surgical trauma, and brachytherapy has already been used successfully after dilatation of peripheral arteries, development of a radioactive source suitable for coronary artery applications would be of great interest. Doses obtained at the surface of the balloon, for a 2-min exposure for the 0.26 mm wire (balloon inflated with air) and the 0.15 mm wire (air or contrast), were 56.5 Gy, 17.8 Gy, 5.4 Gy, respectively. As expected for a beta emitter, the fall-off in dose as a function of depth was rapid. External irradiation from the beta source was negligible. Our experiments indicate that the dose rates attainable at the surface of the angioplasty balloon using this technique allow the doses necessary for the inhibition of intimal cell proliferation to be reached within a relatively short period of time. The thin yttrium-90 wires are very easy to handle, and their mechanical and radioactive properties are well suited to the requirements of the catheterization procedure. 16 refs., 4 figs., 1 tab.

  20. Use of the holmium:YAG laser in coronary disease

    NASA Astrophysics Data System (ADS)

    Heuser, Richard R.

    1992-08-01

    The holmium:YAG laser, a new solid-state, infrared laser system, is being used increasingly more often for treating peripheral vascular disease. We discuss the early use of this device in coronary laser angioplasty. The holmium:YAG laser has several advantages over excimer systems and may prove to be an effective adjunctive to coronary balloon angioplasty.

  1. Recent progress in planetary balloons

    NASA Astrophysics Data System (ADS)

    Kerzhanovich, Viktor V.; Cutts, James A.

    2001-08-01

    In the last 15 years several balloon mission cencepts have been proposed for Mars and Venus, one of them - Russian-French Mars Aerostat - was extensively developed in 1988-1995 but was terminated before completion. It became clear that a number of critical technologies still needed to be developed prior to committing a costly space mission. In recent years significant progress has been made in two critical fields: aerial deployment and inflation of thin-film balloons for specific planetary applications, and in the development of envelope design for stratospheric applications. This paper describes requirements, proposed concepts, critical elements and trade-offs in planetary balloon missions as well as current results of some of JPL balloon programs.

  2. Balloon exoplanet nulling interferometer (BENI)

    NASA Astrophysics Data System (ADS)

    Lyon, Richard G.; Clampin, Mark; Woodruff, Robert A.; Vasudevan, Gopal; Ford, Holland; Petro, Larry; Herman, Jay; Rinehart, Stephen; Carpenter, Kenneth; Marzouk, Joe

    2009-08-01

    We evaluate the feasibility of a balloon-borne nulling interferometer to detect and characterize an exosolar planet and the surrounding debris disk. The existing instrument consists of a three-telescope Fizeau imaging interferometer with thre fast steering mirrors and three delay lines operating at 800 Hz for closed-loop control of wavefront errors and fine pointing. A compact visible nulling interferometer would be coupled to the imaging interferometer and in principle, allows deep starlight suppression. Atmospheric simulations of the environment above 100,000 feet show that balloonborne payloads are a possible path towards the direct detection and characterization of a limited set of exoplanets and debris disks. Furthermore, rapid development of lower cost balloon payloads provide a path towards advancement of NASA technology readiness levels for future space-based exoplanet missions. Discussed are the BENI mission and instrument, the balloon environment and the feasibility of such a balloon-borne mission.

  3. Ballooning Modes and Sustorm Onset

    NASA Astrophysics Data System (ADS)

    Cheng, C. Z.; Zaharia, S.

    2002-12-01

    Based on the AMPTE/CCE observations [Cheng and Lui, GRL, 1998], a low frequency instability with period on the order of 1 min is observed about 2-3 minutes before the substorm onset and is identified as a kinetic ballooning instability. Kinetic effects such as ion gyroradii, magnetic drift, and trapped electrons can strongly enhance the beta threshold over that of ideal MHD ballooning mode theory prediction. However, the ballooning instability threshold based on the ideal MHD model in realistic magnetospheres is still unresolved. Here, we present the stability property of ideal MHD ballooning modes in numerical 3D magnetospheric equilibria with thin current sheet. The coupling effects between perpendicular and parallel (compressional) perturbed magnetic fields are included. The calculations make use of numerical 3D magnetospheric equilibria including thin current sheet by assuming pressure to be constant along a field line. We then, estimate the stability threshold including kinetic effects and compare with observations.

  4. Drug-coated balloon treatment of coronary artery disease: a position paper of the Italian Society of Interventional Cardiology.

    PubMed

    Cortese, Bernardo; Berti, Sergio; Biondi-Zoccai, Giuseppe; Colombo, Antonio; Limbruno, Ugo; Bedogni, Francesco; Cremonesi, Alberto; Silva, Pedro Leon; Sgueglia, Gregory A

    2014-02-15

    Drug-coated balloons are a new tool for the treatment of patients with coronary artery disease. The main feature of this technology is a rapid and homogenous transfer of an antiproliferative drug (paclitaxel) to the vessel wall just at the time of balloon inflation, when neointimal proliferation, in response to angioplasty, is the highest. Moreover, drug-coated balloons share adjuntive advantages over stents: the absence of permanent scaffold and polymer, the respect of the original coronary anatomy, and limited inflammatory stimuli, thereby allowing for short-term dual antiplatelet therapy. To this day, a lot of devices are available in the market, with limited scientific data for the vast majority of them. Thus, the Italian scientific society of interventional cardiologists GISE decided to coordinate the efforts of a group of reknown experts on the field, in order to obtain a Position Paper on the correct use of drug-coated balloons in all the settings of coronary artery disease, giving a class of indication to each one, based on the clinical evidence. This Position Paper represents a quick reference for operators, investigators, and manufactures to promote the understanding and the correct use of the drug-coated balloon technology in everyday clinical practice.

  5. The Brazilian scientific balloon program

    NASA Astrophysics Data System (ADS)

    Braga, Joao

    The Brazilian scientific balloon program is based almost entirely at the National Institute for Space Research -INPE, which has a facility for research and development of scientific balloon systems such as telemetry, command, power supply, separation and flight train devices, ballast control systems, ATC transponders, shock absorbers and especially different launching tech-niques. The Balloon Launching Center of INPE operates since the early 70s, when the first launches were performed in cooperation with French groups for astronomical gamma-ray obser-vations. Since then, the center was involved in a large numbers of international collaborations with France, Japan, United Kingdom, USA, Italy, Germany and Tasmania. INPEs high-energy astrophysics group developed several X and Gamma-ray experiments that were launched in balloons since the early 80s. The most complex of these payloads is the MASCO experiment, launched in 2004. It consists in a 2-ton experiment with a large gamma-ray imaging coded-mask telescope and an attitude control system developed at INPE. Currently, the high-energy group is developing a prototype balloon experiment for the MIRAX satellite, named protoMIRAX. Others scientists at INPE have also used balloons for cosmic rays, geophysics and atmospheric electricity experiments.

  6. "Cutting Balloon and the Three Burrs": treatment for ostial left anterior descending artery in-stent restenosis.

    PubMed

    Osula, Serge; Ramsdale, David R

    2002-02-01

    A 58-year-old man re-presented with symptoms of angina 3 months after percutaneous transluminal coronary angioplasty (PTCA) and stenting to his proximal left anterior descending artery (LAD). Angiography revealed ostial in-stent restenosis of the LAD, which was treated with rotational atherectomy and a cutting balloon PTCA. Combining two useful technologies for treating in-stent restenosis may prove to yield better results than using either technique alone. Long-term benefit will need to be assessed by randomized studies.

  7. Angioplasty and Stenting for Intracranial Stenosis

    PubMed Central

    IZUMI, Takashi; IMAMURA, Hirotoshi; SAKAI, Nobuyuki; MIYACHI, Shigeru

    2014-01-01

    Of the patients enrolled in the Japanese Registry of Neuroendovascular Therapy (JR-NET), a surveillance study in Japanese, 1133 patients who underwent intracranial percutaneous transluminal angioplasty (PTA)/stenting for intracranial stenosis during the period from 2005 to 2009 were investigated. A technical success was achieved in 98.3% of the patients, and 70.5% and 7.5% had a residual stenosis of < 30% and ≥ 50%, respectively. The incidence of ischemic complications and hemorrhagic complications was as low as 7.7% and 2.5%, respectively, but tended to increase in patients who underwent stenting. While a significant correlation with ischemic complications was observed in previously untreated patients and patients who underwent stenting followed by post-dilatation, a significant correlation with hemorrhagic complications was observed in patients who received emergency treatment and those treated between 24 hours and 14 days of the onset. Flexible intracranial stents are expected to contribute to improvement in the treatment outcome. PMID:24390191

  8. [Efficacy of angioplasty of native coarctations of the aorta of the big infant and of the adult with systematic endoprosthesis implantation].

    PubMed

    Fraisse, A; Amabile, N; Errera, J; Aubert, F; Chetaille, P; Kreitmann, B; Metras, D; Durieux, O; Bonnet, J L; Djiane, P

    2004-05-01

    The angioplasty of native coarcatations of the aorta remains a controversial treatment due to recurrences and the potential risk of aneurysm or of descending aorta dissection during catheterization. The interest of a systematic implantation of an endoprothesis is poorly documented. We report our experience in a small series of 3 patients aged from 7, 28 to 52 years at the moment of the angioplasty of their native aortic coarctation. In all the three cases it corresponded to a "membranous" type, localized a the level of the isthmus without hypoplasia of the aortic arch. All presented a refractory hypertension. One patient presented an intermittent claudication related to a low perfusion of lower limbs. The angioplasty was performed with BIB balloon, associated at the same time with the implantation of a Palmaz P308 stent in two cases and Genesis PG2910P in the last patient. The efficacy was immediate in all the 3 cases with stopping antihypertensive drugs at the very day of the procedure. The immediate results were complicated by a bilateral hematoma of the scarpa in a context of excessive anticoagulation in one patient requiring blood tranfusion. After a follow-up of one, 12 and 21 months, all the 3 patients are asymptomatic without any significant residual hypertension. The control scan of the infant confirmed the absence of re-coarctation. In conclusion, the angioplasty followed by systematic implantation of an endoprosthesis is a safe and effective technique for treating simple forms of native coarctations of the aortic isthmus. It can be proposed as a first line treatment for big infants and adults affected by localized types.

  9. Early experiences of intraoperative ultrasound guided angioplasty of the arterial stenosis during upper limb arteriovenous fistula creation.

    PubMed

    Napoli, M; Montinaro, A; Russo, F; De Pascalis, A; Patruno, P; Proia, S; Valletta, A; Vitale, O; Buongiorno, E

    2007-01-01

    In recent years the high prevalence of diabetes and atherosclerosis in elderly uremic patients starting hemodialysis (HD) has led to the increase in the risk of vascular access (VA) failure caused by pre-existing arterial diseases, including both VA slow maturation and early failure, and upper limb ischemic symptoms. Recently, in performing radial (R), brachial (B) and ulnar (U) artery (A) percutaneous transluminal angioplasty (PTA) in HD patients affected by access thrombosis, with insufficient blood flow and severe upper limb ischemia, good outcomes have been reported. Nevertheless, these procedures were performed after arteriovenous fistula (AVF) creation. About 2 years ago, we approached an intra-operative ultrasound-guided transluminal angioplasty (IUTA) performed during AVF creation, using the arterial incision, necessary because of the anastomosis, to introduce the necessary devices for the IUTA. The arterial stenosis having undergone IUTA was diagnosed by a preliminary ultrasound examination. Ultrasound guidance during the procedure is necessary for correct balloon location in the stenosis site. We treated seven patients (four diabetics), mean age 76 + 5 yrs. In all cases, the radial arteries because of hyposphygmia, were unfit for AVF creation. Four distal radio-cephalic AVFs at the wrist were created in patients 1, 3, 4 and 5; in the other three patients (2, 6 and 7), with failure or thrombosis of previous distal AVFs, an immediately upstream anastomosis was performed. In all cases, first, the area selected to perform the AV anastomosis was exposed, then the AR was incised, and the introductory metallic guide wire and the angioplasty catheter (with dimensions decided after PUS), were introduced. The balloon was inflated to 8-13 atm for 30-35 sec. In two patients a stent was also positioned. Later, a side-to-side AVF was created, closing the distal venous vessel. Patient follow-up ranged from 6-22 months. The ultrasound evaluation after IUTA showed the

  10. Adjunct processors in embedded medical imaging systems

    NASA Astrophysics Data System (ADS)

    Trepanier, Marc; Goddard, Iain

    2002-05-01

    Adjunct processors have traditionally been used for certain tasks in medical imaging systems. Often based on application-specific integrated circuits (ASICs), these processors formed X-ray image-processing pipelines or constituted the backprojectors in computed tomography (CT) systems. We examine appropriate functions to perform with adjunct processing and draw some conclusions about system design trade-offs. These trade-offs have traditionally focused on the required performance and flexibility of individual system components, with increasing emphasis on time-to-market impact. Typically, front-end processing close to the sensor has the most intensive processing requirements. However, the performance capabilities of each level are dynamic and the system architect must keep abreast of the current capabilities of all options to remain competitive. Designers are searching for the most efficient implementation of their particular system requirements. We cite algorithm characteristics that point to effective solutions by adjunct processors. We have developed a field- programmable gate array (FPGA) adjunct-processor solution for a Cone-Beam Reconstruction (CBR) algorithm that offers significant performance improvements over a general-purpose processor implementation. The same hardware could efficiently perform other image processing functions such as two-dimensional (2D) convolution. The potential performance, price, operating power, and flexibility advantages of an FPGA adjunct processor over an ASIC, DSP or general-purpose processing solutions are compelling.

  11. State of the art of CO laser angioplasty system

    NASA Astrophysics Data System (ADS)

    Arai, Tsunenori; Mizuno, Kyoichi; Miyamoto, Akira; Sakurada, Masami; Kikuchi, Makoto; Kurita, Akira; Nakamura, Haruo; Takaoka, Hidetsugu; Utsumi, Atsushi; Takeuchi, Kiyoshi

    1994-07-01

    A unique percutaneous transluminal coronary angioplasty system new IR therapy laser with IR glass fiber delivery under novel angioscope guidance was described. Carbon monoxide (CO) laser emission of 5 mm in wavelength was employed as therapy laser to achieve precise ablation of atheromatous plaque with a flexible As-S IR glass fiber for laser delivery. We developed the first medical CO laser as well as As-S IR glass fiber cable. We also developed 5.5 Fr. thin angioscope catheter with complete directional manipulatability at its tip. The system control unit could manage to prevent failure irradiations and fiber damages. This novel angioplasty system was evaluated by a stenosis model of mongrel dogs. We demonstrated the usefulness of our system to overcome current issues on laser angioplasty using multifiber catheter with over-the-guidewire system.

  12. Myocardial protection by intracoronary nicardipine administration during percutaneous transluminal coronary angioplasty.

    PubMed

    Hanet, C; Rousseau, M F; Vincent, M F; Lavenne-Pardonge, E; Pouleur, H

    1987-05-01

    To determine if the calcium antagonist nicardipine protects the myocardium against ischemia, myocardial lactate, hypoxanthine and prostanoid function was studied in 12 patients during percutaneous transluminal coronary angioplasty (PTCA). Values were obtained before balloon inflation and during 4 minutes after deflation. Intracoronary injection of 0.2 mg of nicardipine distal to the stenosis was done randomly before the first or second inflation; the other inflation served as a control. One minute after deflation, coronary sinus flow levels were similar during the nicardipine and control procedure (161 +/- 61 vs 159 +/- 72 ml/min); lactate (-9 +/- 21% vs -17 +/- 21%, p less than 0.025) and hypoxanthine production (-107 +/- 85% vs -218 +/- 153%, p less than 0.05) were less severe after nicardipine pretreatment than after control. All patients reverted to lactate extraction 4 minutes after inflation plus nicardipine infusion, whereas lactate was still produced 4 minutes after control inflation. No significant changes in thromboxane B2 or prostacyclin levels were observed in the coronary sinus 1 minute after inflation, but higher arterial thromboxane B2 values were observed after control inflation than after inflation with nicardipine infusion (median values 169 vs 78 pg/ml, p less than 0.05). In conclusion, intracoronary infusion of nicardipine reduced signs of ischemia and alterations in prostanoid handling after coronary occlusion. The mechanisms of myocardial protection appeared unrelated to coronary sinus blood flow changes or to a systemic effect of nicardipine.

  13. Limb-salvage angioplasty in poor surgical chronic liver disease and diabetic patients.

    PubMed

    Hamdy, Hussam; El-Kolly, M; Ezzat, H; Abbas, M; Farouk, Y; Naser, M; Magdy, M; Elraouf, A

    2013-08-01

    Critical limb ischemia (CLI) in high surgical risk patients with chronic liver diseases has a grave prognosis with a one-year mortality rate of 20% and a one-year amputation rate of 25% after the initial diagnosis. According to Trans-Atlantic Inter-Society Consensus (TASC)-II Guidelines, revascularization (surgical & endovascular) is the treatment of choice for patients with critical limb ischemia (CLI). The primary goal of revascularization is to relieve ischemic rest pain, heal ulcers, prevent amputation, improve patient's quality of life (limb salvage) and secondary goal was the periprocedural complications. Endovascular techniques include balloon angioplasty, stents, stent-grafts, and plaque debulking procedures. Surgical options, identification of patients at risk of postoperative complications could have an impact on the indications for a procedure as well as permitting modifications of treatment to reduce the surgical risk This study evaluated the treatment out comas after limb salvage angioplasty for patients who otherwise would be candidates for primary amputation due to poor co-morbid conditions as chronic liver disease and diabetes. The clinical evaluation, laboratory investigations and abdominal ultrasonography were performed to all patients to evaluate their liver status. Patients were classified according to Child-pugh classification into child A, B & C. All patients were subjected to either detailed arterial duplex or C.T. angiography to assess their arterial lesions from January 2008- January 2010. 95 patients with critical limb ischemia (Rutherford categories 4, 5, 6) were treated by primary percutaneous transluminal angioplasty (PTA). No patient was excluded on the basis of the extent of arterial occlusive disease. The primary end points were immediate technical success, clinical improvement and limb salvages rates. Secondary end points were periprocedural complications and mortality. Most of the patients were male (54.7%) with mean age 62 (48

  14. Clinical experience with peripheral excimer laser angioplasty

    NASA Astrophysics Data System (ADS)

    Visona, Adriana; Cecchetti, Walter; Liessi, Guido; Miserocchi, Luigi; Bonanome, Andrea; Lusiani, Luigi; Mayellaro, Valeria; Pagnan, Antonio

    1993-06-01

    We used an excimer laser system (xenon-chloride at the wavelength of 308 nm) to treat totally occluded peripheral vessels in 71 patients. Energy was delivered through a multifiber catheter, which combines 12 (7F) or 18 (9F) fibers (260 (mu) diameter each), concentrically arranged. Balloon dilatation was associated to complete the procedure in 84% of the cases. The immediate success rate was 97%. The cumulative patency rate was 49% at one year. The major problems with this system were that the stiff multifiber tips caused dissections, and spasm; dead space/active space ratio of the catheter was unfavorable, allowing mechanical `dottering;' the maximum lumen obtained was considered inadequate. After this three year period, the goal of our clinical laser program is to develop a stand alone laser technique by employing a multifiber catheter which combines 130 - 150 fibers 100 (mu) diameter each, and features a quartz coated distal tip.

  15. The Case for Angioplasty in Patients with Symptomatic Intracranial Atherosclerosis

    PubMed Central

    McTaggart, Ryan A.; Marks, Michael P.

    2014-01-01

    Intracranial atherosclerotic disease (ICAD) is likely the most common cause of stroke worldwide and remains highly morbid even with highly monitored medical therapy. Recent results of the SAMMPRIS trial, which randomized patients to stenting plus aggressive medical management versus aggressive medical management alone have shown that additional treatment of intracranial atherosclerotic lesions with the Wingspan stent is inferior to aggressive medical management alone. In light of these results, there has been renewed interest in angioplasty alone to treat symptomatic ICAD. This article will briefly review the natural history of ICAD and discuss the possible future for endovascular treatment of ICAD with primary intracranial angioplasty in appropriately selected patients. PMID:24782816

  16. Aspirin inhibition of platelet deposition at angioplasty sites: demonstration by platelet scintigraphy

    SciTech Connect

    Cuningham, D.A.; Kumar, B.; Siegel, B.A.; Gilula, L.A.; Totty, W.G.; Welch, M.J.

    1984-05-01

    In-111 platelet scintigraphy was used to evaluate the effects of prior aspirin administration on the accumulation of In-111-labeled autologous platelets at sites of arterial injury resulting from iliac, femoral, or popliteal transluminal angioplasty in a nonrandomized study of 17 men. The degree of platelet localization at angioplasty sites was significantly less in nine men who had received aspirin in varying doses within the 4 days before angioplasty than in eight men who had not received aspirin for at least two weeks. The results suggest that aspirin treatment before angioplasty limits the early platelet deposition at the angioplasty site in men.

  17. The CNES Balloon Program : an overview

    NASA Astrophysics Data System (ADS)

    Debouzy, G.; Cazaux, C.

    The CNES (French Space Agency) Balloon Program continues to support the scientific community providing enhanced measurements capabilities across different kind of balloons: zero pressure balloon (80 % of activities), Infra-Red Montgolfiere (MIR) and superpressure balloon. For ENVISAT satellite validation, CNES has set up with ESA an important international balloon program with six dedicated campaigns, in 2002 - 2004 period, from mid-latitude; northern and tropical balloon launch facilities. In the framework of an European program, CNES participates to HIBISCUS project by organizing balloon campaigns (2003 & 2004) in tropical region with the launches of zero-pressure balloon, MIR and superpressure balloon from the same facility. In cooperation with US, CNES is preparing the VORCORE project which consists to study the atmospheric circulation of Antarctica polar vortex, using superpressure balloons launched from the Mac-Murdo station. This paper will present the CNES balloon activities in the 2002-2004 period, mainly focused on atmospheric chemistry, will give an overview of balloon technology development, and will present also the JAXA / CNES cooperation for the HSFD shuttle drop from stratospheric balloons with a first flight realized in 2003.

  18. Protective effect of melatonin on cigarette smoke-induced restenosis in rat carotid arteries after balloon injury.

    PubMed

    Yang, Gen-Huan; Li, Yan-Chuan; Wang, Zhan-Qi; Liu, Bao; Ye, Wei; Ni, Leng; Zeng, Rong; Miao, Shi-Ying; Wang, Lin-Fang; Liu, Chang-Wei

    2014-11-01

    Vascular restenosis after the interventional angioplasty remains the main obstacle to a favorable long-term patency. Many researches suggest cigarette smoking is one of the most important causes of restenosis. This study was designed to investigate whether melatonin could protect against the cigarette smoke-induced restenosis in rat carotid arteries after balloon injury. Three groups of male rats (normal condition, cigarette smoke exposed, cigarette smoke exposed, and melatonin injected) were used in this study. An established balloon-induced carotid artery injury was performed, and the carotid arteries were harvested from these three groups 14 days later. The ratio of intima to media, the infiltration of inflammatory cells, the expression of inflammatory cytokines (NF-κB, IL-1β, IL-6, TNF-α, MCP-1), adhesion molecules (ICAM-1, VCAM-1), and eNOS were measured. The results showed that cigarette smoke exposure aggravated the stenosis of the lumen, promoted the infiltration of inflammatory cells and induced the expression of the inflammatory cytokines and adhesion molecules after the balloon-induced carotid artery injury. Moreover, cigarette smoke exposure can inhibit the expression of eNOS. Particularly, we surprised that melatonin could minimize this effect caused by cigarette smoke. These results suggested that melatonin could prevent the cigarette smoke-induced restenosis in rat carotid arteries after balloon injury and the mechanism of its protective effect may be the inhibition of the inflammatory reaction. This also implies melatonin has the potential therapeutic applicability in prevention of restenosis after the vascular angioplasty in smokers.

  19. Evaluation of a balloon occlusion and aspiration system for protection from distal embolization during stenting in saphenous vein grafts.

    PubMed

    Grube, Eberhard; Schofer J, J ürgen; Webb, John; Schuler, Gerhard; Colombo, Antonio; Sievert, Horst; Gerckens, Ulrich; Stone, Gregg W

    2002-04-15

    Distal embolization after angioplasty in degenerated saphenous vein grafts (SVGs) results in high rates of periprocedural myonecrosis and mortality. Temporary protection of the distal microcirculation with aspiration of dislodged debris may improve the safety of SVG intervention. To evaluate the feasibility, safety, and efficacy of distal protection using the PercuSurge GuardWire Occlusion and Aspiration System, 103 consecutive patients undergoing planned stenting of 105 SVG lesions were prospectively enrolled in a multinational, multicenter study. Before angioplasty, protection of the distal circulation was achieved with the PercuSurge GuardWire distal balloon occlusion system, followed by stenting and debris aspiration. Quality assurance measures in the study included independent on-site data monitoring, clinical event adjudication, data analysis, and use of multiple core laboratories. Mean graft age was 8.9 +/- 4.0 years. The duration of distal balloon inflation was 5.4 +/- 3.7 minutes; premature balloon deflation for ischemia was not required in any patient. Macroscopically visible red and/or yellow debris was extracted in 91% of patients. By core lab analysis, postprocedural Thrombolysis In Myocardial Infarction-III flow was present in 98.9% of grafts (vs 83.5% before intervention). No patient developed angiographic evidence of no reflow or distal embolization. Postprocedural creatine phosphokinase MB isozyme levels were elevated to >3 x normal in only 5 patients (5%), and 97 patients (94%) were free of major adverse events at 30 days. We conclude that the GuardWire distal balloon occlusion and aspiration system is an effective and safe method for protecting distal microcirculation from the adverse consequences of embolization during mechanical intervention of degenerated SVGs.

  20. Structure variations of pumpkin balloon

    NASA Astrophysics Data System (ADS)

    Yajima, N.; Izutsu, N.; Honda, H.

    2004-01-01

    A lobed pumpkin balloon by 3-D gore design concept is recognized as a basic form for a super-pressure balloon. This paper deals with extensions of this design concept for other large pressurized membrane structures, such as a stratospheric airship and a balloon of which volume is controllable. The structural modifications are performed by means of additional ropes, belts or a strut. When the original pumpkin shape is modified by these systems, the superior characteristics of the 3-D gore design, incorporating large bulges with a small local radius and unidirectional film tension, should be maintained. Improved design methods which are adequate for the above subjects will be discussed in detail. Application for ground structures are also mentioned.

  1. Balloon Exoplanet Nulling Interferometer (BENI)

    NASA Technical Reports Server (NTRS)

    Lyon, Richard G.; Clampin, Mark; Woodruff, Robert A.; Vasudevan, Gopal; Ford, Holland; Petro, Larry; Herman, Jay; Rinehart, Stephen; Carpenter, Kenneth; Marzouk, Joe

    2009-01-01

    We evaluate the feasibility of using a balloon-borne nulling interferometer to detect and characterize exosolar planets and debris disks. The existing instrument consists of a 3-telescope Fizeau imaging interferometer with 3 fast steering mirrors and 3 delay lines operating at 800 Hz for closed-loop control of wavefront errors and fine pointing. A compact visible nulling interferometer is under development which when coupled to the imaging interferometer would in-principle allow deep suppression of starlight. We have conducted atmospheric simulations of the environment above 100,000 feet and believe balloons are a feasible path forward towards detection and characterization of a limited set of exoplanets and their debris disks. Herein we will discuss the BENI instrument, the balloon environment and the feasibility of such as mission.

  2. Taking the Hot Air Out of Balloons.

    ERIC Educational Resources Information Center

    Brinks, Virgil L.; Brinks, Robyn L.

    1994-01-01

    Describes how a teacher can give their students the challenge of designing and building model balloons or blimps. The project helps students learn the basics of balloon flight and what it really means to be "lighter than air." (PR)

  3. NASA Aeronautics Showcased at Balloon Fiesta

    NASA Video Gallery

    Visitors at the 2010 International Balloon Fiesta in Albuquerque, N.M., got visual stimulation from hundreds of colorful hot-air balloons soaring skyward, but also learned about NASA's aeronautics ...

  4. Yellow Balloon in a Briar Patch.

    ERIC Educational Resources Information Center

    Cooper, Frank; Fitzmaurice, Robert W.

    1978-01-01

    As part of a meteorology unit, sixth grade science students launched helium balloons with attached return postcards. This article describes Weather Service monitoring of the balloons and postcard return results. (MA)

  5. The EUSO-Balloon pathfinder

    NASA Astrophysics Data System (ADS)

    Adams, J. H.; Ahmad, S.; Albert, J.-N.; Allard, D.; Anchordoqui, L.; Andreev, V.; Anzalone, A.; Arai, Y.; Asano, K.; Ave Pernas, M.; Baragatti, P.; Barrillon, P.; Batsch, T.; Bayer, J.; Bechini, R.; Belenguer, T.; Bellotti, R.; Belov, K.; Berlind, A. A.; Bertaina, M.; Biermann, P. L.; Biktemerova, S.; Blaksley, C.; Blanc, N.; Błȩcki, J.; Blin-Bondil, S.; Blümer, J.; Bobik, P.; Bogomilov, M.; Bonamente, M.; Briggs, M. S.; Briz, S.; Bruno, A.; Cafagna, F.; Campana, D.; Capdevielle, J.-N.; Caruso, R.; Casolino, M.; Cassardo, C.; Castellinic, G.; Catalano, C.; Catalano, G.; Cellino, A.; Chikawa, M.; Christl, M. J.; Cline, D.; Connaughton, V.; Conti, L.; Cordero, G.; Crawford, H. J.; Cremonini, R.; Csorna, S.; Dagoret-Campagne, S.; de Castro, A. J.; De Donato, C.; de la Taille, C.; De Santis, C.; del Peral, L.; Dell'Oro, A.; De Simone, N.; Di Martino, M.; Distratis, G.; Dulucq, F.; Dupieux, M.; Ebersoldt, A.; Ebisuzaki, T.; Engel, R.; Falk, S.; Fang, K.; Fenu, F.; Fernández-Gómez, I.; Ferrarese, S.; Finco, D.; Flamini, M.; Fornaro, C.; Franceschi, A.; Fujimoto, J.; Fukushima, M.; Galeotti, P.; Garipov, G.; Geary, J.; Gelmini, G.; Giraudo, G.; Gonchar, M.; González Alvarado, C.; Gorodetzky, P.; Guarino, F.; Guzmán, A.; Hachisu, Y.; Harlov, B.; Haungs, A.; Hernández Carretero, J.; Higashide, K.; Ikeda, D.; Ikeda, H.; Inoue, N.; Inoue, S.; Insolia, A.; Isgrò, F.; Itow, Y.; Joven, E.; Judd, E. G.; Jung, A.; Kajino, F.; Kajino, T.; Kaneko, I.; Karadzhov, Y.; Karczmarczyk, J.; Karus, M.; Katahira, K.; Kawai, K.; Kawasaki, Y.; Keilhauer, B.; Khrenov, B. A.; Kim, J.-S.; Kim, S.-W.; Kim, S.-W.; Kleifges, M.; Klimov, P. A.; Kolev, D.; Kreykenbohm, I.; Kudela, K.; Kurihara, Y.; Kusenko, A.; Kuznetsov, E.; Lacombe, M.; Lachaud, C.; Lee, J.; Licandro, J.; Lim, H.; López, F.; Maccarone, M. C.; Mannheim, K.; Maravilla, D.; Marcelli, L.; Marini, A.; Martinez, O.; Masciantonio, G.; Mase, K.; Matev, R.; Medina-Tanco, G.; Mernik, T.; Miyamoto, H.; Miyazaki, Y.; Mizumoto, Y.; Modestino, G.; Monaco, A.; Monnier-Ragaigne, D.; Morales de los Ríos, J. A.; Moretto, C.; Morozenko, V. S.; Mot, B.; Murakami, T.; Murakami, M. Nagano; Nagata, M.; Nagataki, S.; Nakamura, T.; Napolitano, T.; Naumov, D.; Nava, R.; Neronov, A.; Nomoto, K.; Nonaka, T.; Ogawa, T.; Ogio, S.; Ohmori, H.; Olinto, A. V.; Orleański, P.; Osteria, G.; Panasyuk, M. I.; Parizot, E.; Park, I. H.; Park, H. W.; Pastircak, B.; Patzak, T.; Paul, T.; Pennypacker, C.; Perez Cano, S.; Peter, T.; Picozza, P.; Pierog, T.; Piotrowski, L. W.; Piraino, S.; Plebaniak, Z.; Pollini, A.; Prat, P.; Prévôt, G.; Prieto, H.; Putis, M.; Reardon, P.; Reyes, M.; Ricci, M.; Rodríguez, I.; Rodríguez Frías, M. D.; Ronga, F.; Roth, M.; Rothkaehl, H.; Roudil, G.; Rusinov, I.; Rybczyński, M.; Sabau, M. D.; Sáez-Cano, G.; Sagawa, H.; Saito, A.; Sakaki, N.; Sakata, M.; Salazar, H.; Sánchez, S.; Santangelo, A.; Santiago Crúz, L.; Sanz Palomino, M.; Saprykin, O.; Sarazin, F.; Sato, H.; Sato, M.; Schanz, T.; Schieler, H.; Scotti, V.; Segreto, A.; Selmane, S.; Semikoz, D.; Serra, M.; Sharakin, S.; Shibata, T.; Shimizu, H. M.; Shinozaki, K.; Shirahama, T.; Siemieniec-Oziȩbło, G.; Silva López, H. H.; Sledd, J.; Słomińska, K.; Sobey, A.; Sugiyama, T.; Supanitsky, D.; Suzuki, M.; Szabelska, B.; Szabelski, J.; Tajima, F.; Tajima, N.; Tajima, T.; Takahashi, Y.; Takami, H.; Takeda, M.; Takizawa, Y.; Tenzer, C.; Tibolla, O.; Tkachev, L.; Tokuno, H.; Tomida, T.; Tone, N.; Toscano, S.; Trillaud, F.; Tsenov, R.; Tsunesada, Y.; Tsuno, K.; Tymieniecka, T.; Uchihori, Y.; Unger, M.; Vaduvescu, O.; Valdés-Galicia, J. F.; Vallania, P.; Valore, L.; Vankova, G.; Vigorito, C.; Villaseñor, L.; von Ballmoos, P.; Wada, S.; Watanabe, J.; Watanabe, S.; Watts, J.; Weber, M.; Weiler, T. J.; Wibig, T.; Wiencke, L.; Wille, M.; Wilms, J.; Włodarczyk, Z.; Yamamoto, T.; Yamamoto, Y.; Yang, J.; Yano, H.; Yashin, I. V.; Yonetoku, D.; Yoshida, K.; Yoshida, S.; Young, R.; Zotov, M. Yu.; Zuccaro Marchi, A.

    2015-11-01

    EUSO-Balloon is a pathfinder for JEM-EUSO, the Extreme Universe Space Observatory which is to be hosted on-board the International Space Station. As JEM-EUSO is designed to observe Ultra-High Energy Cosmic Rays (UHECR)-induced Extensive Air Showers (EAS) by detecting their ultraviolet light tracks "from above", EUSO-Balloon is a nadir-pointing UV telescope too. With its Fresnel Optics and Photo-Detector Module, the instrument monitors a 50 km2 ground surface area in a wavelength band of 290-430 nm, collecting series of images at a rate of 400,000 frames/sec. The objectives of the balloon demonstrator are threefold: a) perform a full end-to-end test of a JEM-EUSO prototype consisting of all the main subsystems of the space experiment, b) measure the effective terrestrial UV background, with a spatial and temporal resolution relevant for JEM-EUSO. c) detect tracks of ultraviolet light from near space for the first time. The latter is a milestone in the development of UHECR science, paving the way for any future space-based UHECR observatory. On August 25, 2014, EUSO-Balloon was launched from Timmins Stratospheric Balloon Base (Ontario, Canada) by the balloon division of the French Space Agency CNES. From a float altitude of 38 km, the instrument operated during the entire astronomical night, observing UV-light from a variety of ground-covers and from hundreds of simulated EASs, produced by flashers and a laser during a two-hour helicopter under-flight.

  6. Adjunct Faculty QUEST Survey: Fall 2001.

    ERIC Educational Resources Information Center

    Howard Community Coll., Columbia, MD. Office of Planning and Evaluation.

    This report presents the highlights from the 2001 QUEST (Quality Education for Students and Teachers) Survey for Adjunct Faculty, administered in November 2001 at Howard Community College (HCC) (Maryland). The survey listed 64 service areas to be rated on a 5-point scale ranging from poor (1) to excellent (5), or to indicate if they were…

  7. THE EFFECTIVENESS OF ADJUNCT AUTO-INSTRUCTION.

    ERIC Educational Resources Information Center

    KINZER, JOHN R.; WORCESTER, DEAN A.

    THE QUESTION OF PRIMARY CONCERN IN FOUR STUDIES WAS IMMEDIATE FEEDBACK IN ADJUNCT AUTOINSTRUCTIONAL EXERCISES (LEARNING EXERCISES DEFINED AS THOSE DESIGNED TO TAKE ADVANTAGE OF THE STRUCTURE INHERENT IN SUBJECT MATTER). IN A CONTROLLED SITUATION, DIFFERENT FEEDBACK DELAYS (IMMEDIATE, 1-HOUR DELAY, 2-DAY DELAY, AND 1-WEEK DELAY) WERE TESTED. OTHER…

  8. Outward Bound as an Adjunct to Therapy.

    ERIC Educational Resources Information Center

    Chase, Nelson K.

    The Colorado Outward Bound School (COBS) provides successful adjunct programs for special populations undergoing therapy at the Adventure Home (Boulder, CO), the Juvenile Justice Program and the St. Luke's Hospital Alcoholism Recovery Unit (Denver, CO), and the Dartmouth-Hitchcock Medical Center Department of Psychiatry (Hanover, NH). The goals of…

  9. Adjuncts: Solutions for a Mistreated Majority

    ERIC Educational Resources Information Center

    Louis, Deborah

    2009-01-01

    According to best estimates, some 800,000 faculty members, close to two-thirds of the total nationwide, are adjunct, "contingent," or "lecturer." The severity of their plight, rapidly worsening in today's economic crisis, intersects the interrelated domains of human rights, fair employment, and the future of higher education. In those areas where…

  10. Effects of Cognitive Adjunct Treatments on Assertiveness.

    ERIC Educational Resources Information Center

    Derry, Paul A.; Stone, Gerald L.

    This study examined the contribution of cognitively-oriented adjunct treatments to assertive training. Unassertive university students (N=42) were randomly assigned within an analysis of covariance design with three levels of treatment (Cognitive Self-Statement Training (CSST), Attribution Training (AT), and Behavioral Rehearsal (BR]. Multiple…

  11. Effective Leadership of Online Adjunct Faculty

    ERIC Educational Resources Information Center

    Tipple, Robert

    2010-01-01

    Post secondary education leaders and administrators are currently facing two separate but inter-related trends: the growth in online education, and the significant increase in adjunct (part-time) faculty. In order to maximize the educational quality and institutional effectiveness, education leaders must develop an approach that levers the…

  12. Adjuncts Fight Back over Academic Freedom

    ERIC Educational Resources Information Center

    Wilson, Robin

    2008-01-01

    Steven Bitterman was fired by his school after he offended his students for telling them that they could easily appreciate the biblical story of Adam and Eve if they considered it a myth. Several adjunct and full-time professors who work off the tenure track have been fired after saying something, as Mr. Bitterman did, that offended students or…

  13. History and perspectives of scientific ballooning

    NASA Astrophysics Data System (ADS)

    Lefevre, Frank

    2001-08-01

    Prehistory: Robertson, Biot and Gay-Lussac; Glaisher and the first studies of the atmosphere; Flammarion. The rebirth of scientific ballooning: polyethylene and mylar vehicles at Minneapolis. Super-pressurized balloons. The CNES and the Nasa programs; meteorology, aeronomy and astronomy, The Eole program. The Venus and Mars balloons in the French-Soviet space program. The future.

  14. 21 CFR 874.4100 - Epistaxis balloon.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4100 Epistaxis balloon. (a) Identification. An epistaxis balloon is a device consisting of an inflatable balloon intended to control...

  15. 21 CFR 874.4100 - Epistaxis balloon.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4100 Epistaxis balloon. (a) Identification. An epistaxis balloon is a device consisting of an inflatable balloon intended to control...

  16. Delayed rupture of renal artery after renal percutaneous transluminal angioplasty

    SciTech Connect

    Puijlaert, C.B.A.J.; Mali, W.P.; Rosenbusch, G.; van Straalen, A.M.; Klinge, J.; Feldberg, M.A.M.

    1986-06-01

    Two cases are reported in which rupture of the renal artery occurred many hours after renal percutaneous transluminal angioplasty. Delayed rupture can be recognized by the angiographic appearance and by the presence of persistent flank pain. The typical angiographic finding is a poorly defined zone of contrast medium at the site of perforation.

  17. Adjunct Faculty Organizational Sense of Belonging and Affective Organizational Commitment

    ERIC Educational Resources Information Center

    Merriman, Constance L.

    2010-01-01

    In recent years all public higher education institutions have increased their reliance on adjunct faculty. Adjuncts provide expertise in key areas, are available at times that meet the needs of the changing student demographic, and cover an increasing number of introductory courses. It has been suggested that adjunct faculty may be more weakly…

  18. Adjuncts in Social Work Programs: Good Practice or Unethical?

    ERIC Educational Resources Information Center

    Pearlman, Catherine A.

    2013-01-01

    Social work education programs rely heavily on adjunct instructors, as do most academic institutions. This article adds to existing literature on adjuncts by focusing on the unique issues in social work education, using social work values and ethics as a focus. The benefits and detriments for adjuncts, programs, and students in schools of social…

  19. Global electrodynamics from superpressure balloons

    NASA Astrophysics Data System (ADS)

    Holzworth, R. H.; Hu, H.

    1995-08-01

    Electric field and conductivity measurements in the stratosphere between November 1992 and March 1993 have been made using superpressure balloons in the southern hemisphere. Over 400 payload-days of data have been made during a record setting experiment called ELBBO (Extended Life Balloon Borne Observatories). This experiment resulted in 4 flights aloft simultaneously for over 2 months including one flight which lasted over 4 months. Electrodynamical coupling between the atmosphere and ionosphere is studied using the measured electric fields, and a simple empirical model of the stratospheric conductivity. Altitude profiles of conductivity have been obtained from several superpressure balloon flights using the large end-of-flight altitude swings on the last few days of each flight (as the balloon begins to loose superpressure). Coupling between the fields and atmospheric inertial waves has been observed. Effects and dynamics of the global circuit suggest that standard models are missing significant phenomena. Large scale ionospheric convection activity has been studied from the polar cap to the middle latitudes. Cusp latitude fields have been continuously measured for many days in a row.

  20. Simulating clefts in pumpkin balloons

    NASA Astrophysics Data System (ADS)

    Baginski, Frank; Brakke, Kenneth

    2010-02-01

    The geometry of a large axisymmetric balloon with positive differential pressure, such as a sphere, leads to very high film stresses. These stresses can be significantly reduced by using a tendon re-enforced lobed pumpkin-like shape. A number of schemes have been proposed to achieve a cyclically symmetric pumpkin shape, including the constant bulge angle (CBA) design, the constant bulge radius (CBR) design, CBA/CBR hybrids, and NASA’s recent constant stress (CS) design. Utilizing a hybrid CBA/CBR pumpkin design, Flight 555-NT in June 2006 formed an S-cleft and was unable to fully deploy. In order to better understand the S-cleft phenomenon, a series of inflation tests involving four 27-m diameter 200-gore pumpkin balloons were conducted in 2007. One of the test vehicles was a 1/3-scale mockup of the Flight 555-NT balloon. Using an inflation procedure intended to mimic ascent, the 1/3-scale mockup developed an S-cleft feature strikingly similar to the one observed in Flight 555-NT. Our analysis of the 1/3-scale mockup found it to be unstable. We compute asymmetric equilibrium configurations of this balloon, including shapes with an S-cleft feature.

  1. Global electrodynamics from superpressure balloons

    NASA Technical Reports Server (NTRS)

    Holzworth, R. H.; Hu, H.

    1995-01-01

    Electric field and conductivity measurements in the stratosphere between November 1992 and March 1993 have been made using superpressure balloons in the southern hemisphere. Over 400 payload-days of data have been made during a record setting experiment called ELBBO (Extended Life Balloon Borne Observatories). This experiment resulted in 4 flights aloft simultaneously for over 2 months including one flight which lasted over 4 months. Electrodynamical coupling between the atmosphere and ionosphere is studied using the measured electric fields, and a simple empirical model of the stratospheric conductivity. Altitude profiles of conductivity have been obtained from several superpressure balloon flights using the large end-of-flight altitude swings on the last few days of each flight (as the balloon begins to loose superpressure). Coupling between the fields and atmospheric inertial waves has been observed. Effects and dynamics of the global circuit suggest that standard models are missing significant phenomena. Large scale ionospheric convection activity has been studied from the polar cap to the middle latitudes. Cusp latitude fields have been continuously measured for many days in a row.

  2. Stability of the pumpkin balloon

    NASA Astrophysics Data System (ADS)

    Baginski, Frank

    A large axisymmetric balloon with positive differential pressure, e.g., a sphere, leads to high film stresses. These can be significantly reduced by using a lobed pumpkin-like shape re-enforced with tendons. A number of schemes have been proposed to achieve a cyclically symmetric pumpkin-shape at full inflation, including the constant bulge angle (CBA) design and the constant bulge radius (CBR) design. The authors and others have carried out stability studies of CBA and CBR designs and found instabilities under various conditions. While stability seems to be a good indicator of deployment problems for large balloons under normal ascent conditions, one cannot conclude that a stable design will deploy reliably. Nevertheless, stability analysis allows one to quantify certain deployment characteristics. Ongoing research by NASA's Balloon Program Office utilizes a new design approach developed by Rodger Farley, NASA/GSFC, that takes into account film and tendon strain. We refer to such a balloon as a constant stress (CS) pumpkin design. In June 2006, the Flight 555-NT balloon (based on a hybrid CBR/CBA design) developed an S-cleft and did not deploy. In order to understand the S-cleft phenomena and study a number of aspects related to the CS-design, a series of inflation tests were conducted at TCOM, Elizabeth City, NC in 2007. The test vehicles were 27 meter diameter pumpkins distinguished by their respective equatorial bulge angles (BA). For example, BA98 indicates an equatorial bulge angle of 98° . BA90, BA55, and BA00 are similarly defined. BA98 was essentially a one-third scale version of of the Flight 555 balloon (i.e., 12 micron film instead of 38.1 micron, mini-tendons, etc.). BA90 and BA55 were Farley CS-designs. BA00 was derived from the BA55 design so that a flat chord spanned adjacent tendons. In this paper, we will carry out stability studies of BA98, BA90, BA55, and BA00. We discuss the deployment problem of pumpkin balloons in light of 2007 inflation

  3. Evaluation of a New Balloon Catheter for Difficult Calcified Lesions in Infrainguinal Arterial Disease: Outcome of a Multicenter Registry

    SciTech Connect

    Spaargaren, G. J.; Lee, M. J.; Reekers, J. A.; Overhagen, H. van; Schultze Kool, L. J.; Hoogeveen, Y. L.

    2009-01-15

    The purpose of this study was to assess the technical performance and immediate procedure outcome of a new balloon catheter in the treatment of calcified lesions in infrainguinal arterial disease. Seventy-five patients with infrainguinal arterial disease were prospectively entered into the registry. The catheter (ReeKross Clearstream, Ireland) is a 5- to 6-Fr balloon catheter with a rigid shaft intended for enhanced pushability. Only technical procedural outcome was recorded. Treated calcified lesions (range: 5-30 cm), assessed angiographically, were located in the superficial femoral, popliteal, and crural arteries. In 67 patients the lesion was an occlusion. Guidewire passage occurred subintimally in 68 patients. In 24 patients a standard balloon catheter was chosen as first treatment catheter: 5 failed to cross the lesion, 8 balloons ruptured, and in 11 patients there was an inadequate dilatation result. In only one of the five patients did subsequent use of the ReeKross catheter also fail in lesion crossing. The ReeKross was successful as secondary catheter in the other 23 cases. In 50 patients the ReeKross was used as primary catheter. In total the ReeKross crossed the lesions in 74 patients. After passage and dilatation with this catheter in 73 patients (1 failed true-lumen reentry), 19 had >30% residual lesions, of which 11 were not treated and 8 were successfully stented. No ReeKross balloons ruptured. We conclude that in the treatment of difficult calcified lesions in arterial stenotic or occlusive disease, the choice of a high-pushability angioplasty catheter, with more calcification-resistant balloon characteristics, like the ReeKross, warrants consideration.

  4. Scientific ballooning: Past, present and future

    NASA Astrophysics Data System (ADS)

    Jones, W. Vernon

    2013-02-01

    Balloons have been used for scientific research since they were invented in France more than 200 years ago. Cosmic rays were discovered 100 years ago with an experiment flown on a manned balloon. A major change in balloon design occurred in 1950 with the introduction of the socalled natural shape balloon with integral load tapes. This basic design has been used with more or less continuously improved materials for scientific balloon flights for the past half century, including long-duration balloon (LDB) flights around Antarctica for the past two decades. The U.S. National Aeronautics and Space Administration (NASA) is currently developing a super-pressure balloon that would enable extended duration missions above 99.5% of the Earth's atmosphere at any latitude. Ultra-long-duration balloon (ULDB) flights enabled by constant-volume balloons should result in an even greater sea change in scientific ballooning than the inauguration of long-duration balloon (LDB) flights in Antarctica during the 1990-91 austral summer.

  5. Results of a Peripheral Cutting Balloon Prospective Multicenter European Registry in Hemodialysis Vascular Access

    SciTech Connect

    Peregrin, Jan H. Rocek, Miloslav

    2007-04-15

    Purpose. To report initial experience with the Peripheral Cutting Balloon (PCB) in treatment of failing hemodialysis shunts. Methods. A total of 190 patients (95 men, 95 women; average age 64.4 {+-} 11.9 years, range 32-87 years) who were treated with the PCB for pressure-resistant stenosis, restenosis or failed percutaneous transluminal angioplasty (PTA) in the venous limb of an arteriovenous shunt were followed in seven European centers using a simple registry. The group consisted of 109 de novo lesions (57%) and 79 restenotic lesions (43%). Results. Technical success was achieved in 88.9% of cases. Primary patency was as follows (the results for whole group and simultaneous results for de novo lesions and restenoses are presented): 1 month (140 patients followed): 94%, 98%, and 93%; 3 months (116 patients followed): 93%, 98%, and 92%; 6 months (40 patients followed): 85%, 92%, and 79%; 12 months (27 patients followed): 74%, 87%, and 48%. No complication occurred. Patients experienced an equal or lower level of pain during the procedure compared with conventional PTA. Conclusion. The PCB proved to be successful in dilating pressure-resistant stenoses. We cannot conclude whether PCB angioplasty can lower the restenosis rate in hemodialysis access lesions, but the long-term patency for de novo lesions is high. A further randomized study is advisable.

  6. Percutaneous transluminal angioplasty for atherosclerotic stenosis of the intracranial cerebral arteries. initial results and long-term follow-up.

    PubMed

    Hyodo, A; Kato, N; Nakai, Y; Anno, I; Sato, H; Okazaki, M; Matsumaru, Y; Nose, T

    1999-11-01

    Percutaneous transluminal angioplasty (PTA) was carried out 52 times for 49 lesions in 47 cases of atheroscrelotic stenosis of the intracranial or skull base cerebral arteries. The stenotic lesions involved the middle cerebral artery in 21 cases, the basilar artery in eight cases, the internal carotid artery (petrous-supraclinoid portion) in 15 cases, and the intracranial vertebral artery in five cases. Nearly all cases were symptomatic, such as TIA or stroke, and the degree of stenosis ranged from 70 to 99 percent, with a mean of 80 percent. PTA was performed using a STEALTH balloon angioplasty catheter. In these trials, PTA was successfully performed (as indicated by a residual stenosis under 50%) 41 times. The initial success rate was 79% and stenosis was reduced from 80% to 25%. Clinical follow-up was performed from 7 to 84 months with a mean of 44 months. During this period, death due to myocardial infarction or pneumonia occurred in five cases, stroke related to previous PTA occurred ih one case (due to re-stenosis) and stroke unrelated tl? previous PTA occurred in two cases. Angiographic follow-up was performed in 31 cases after 41 successful PTA procedures. Re-stenosis was seen in 20% of the cases, symptomrltic complications occurred in 6%, and asymptomatic complications occurred in 6% of the cases. One case suffered severe subarachnoid hemorrhage just after the PTA due to preexisting aneurysm rupture and he died a week after the PTA. So mortality in this series was 2%. From the results described here, we may conclude that PTA of the intracranial or skull base cerebral artery is technically feasible, and it can be performed with relatively low risk. From our results, it may be a useful method and effective for long-term survival of patients. But results from a larger number of patients and more long-term follow-up data are still necessary in order to evaluate the safety and usefulness of this method.

  7. Interference in the processing of adjunct control

    PubMed Central

    Parker, Dan; Lago, Sol; Phillips, Colin

    2015-01-01

    Recent research on the memory operations used in language comprehension has revealed a selective profile of interference effects during memory retrieval. Dependencies such as subject–verb agreement show strong facilitatory interference effects from structurally inappropriate but feature-matching distractors, leading to illusions of grammaticality (Pearlmutter et al., 1999; Wagers et al., 2009; Dillon et al., 2013). In contrast, dependencies involving reflexive anaphors are generally immune to interference effects (Sturt, 2003; Xiang et al., 2009; Dillon et al., 2013). This contrast has led to the proposal that all anaphors that are subject to structural constraints are immune to facilitatory interference. Here we use an animacy manipulation to examine whether adjunct control dependencies, which involve an interpreted anaphoric relation between a null subject and its licensor, are also immune to facilitatory interference effects. Our results show reliable facilitatory interference in the processing of adjunct control dependencies, which challenges the generalization that anaphoric dependencies as a class are immune to such effects. To account for the contrast between adjunct control and reflexive dependencies, we suggest that variability within anaphora could reflect either an inherent primacy of animacy cues in retrieval processes, or differential degrees of match between potential licensors and the retrieval probe. PMID:26441723

  8. Development of scientific ballooning in Japan

    NASA Astrophysics Data System (ADS)

    Nishimura, Jun

    On the occasion of the 50th Anniversary Celebration of COSPAR of this year of 2008, it is worthwhile to summarize the results of the Scientific ballooning in early days in connection with the recent developments in various countries. Nishina Laboratories, Riken, had started the observations of cosmic rays with rubber balloons as early as 1942. However it was interrupted soon by the war II. After the war, new research group started in collaboration with several universities with nuclear emulsions put on the rubber balloons in 1950, and then soon after the group manufactured by themselves and launched the first plastic balloon in 1953. Based on additional technologies during a few years developed by these group, the Institute of Nuclear Study, INS, the University of Tokyo, organized the large campaign of 14 emulsion chambers and a pellicle stack with 8 plastic balloons in 1956. It is to be noted that the project was one of the largest in the world standard in those days. By the experience of this campaign, the importance of the balloon technologies was more recognized, and INS organized the group to study the balloon technologies, and had established some developments. The systematic study of scientific ballooning has started, when the scientific ballooning laboratory was founded in 1965, in the new Institute of ISAS, the University of Tokyo. The permanent balloon base of "Sanriku Balloon Center" was founded in 1971. This group has expended all efforts for the scientific ballooning, launching 10-20 balloons in each year with new inventions such as the studies of; Technologies to manufacture the reliable plastic balloons, New Balloon materials, New instrumentations for scientific ballooning, Systems of long duration flights including Antarctica flights, International collaboratiom, etc. Up to now almost 600 plastic balloons were launched during past 50 years. Then the scientific balloonings have played important and indispensable roles for the development of space

  9. A method for balloon trajectory control

    NASA Astrophysics Data System (ADS)

    Aaron, K. M.; Heun, M. K.; Nock, K. T.

    A balloon trajectory control system is discussed that is under development for use on NASA's Ultra Long Duration Balloon Project. The trajectory control system exploits the natural wind field variation with altitude to generate passive lateral control forces on a balloon using a tether-deployed aerodynamic surface below the balloon. A lifting device, such as a wing on end, is suspended on a tether well beneath the balloon to take advantage of this variation in wind velocity with altitude. The wing generates a horizontal lift force that can be directed over a wide range of angles. This force, transmitted to the balloon by a tether, alters the balloon's path providing a bias velocity of a few meters per second to the balloon drift rate. The trajectory control system enables the balloon to avoid hazards, reach targets, steer around avoidance countries and select convenient landing zones. No longer will balloons be totally at the mercy of the winds. Tests in April 1999 of a dynamically-scaled model of the trajectory control system were carried out by Global Aerospace Corporation in ground level winds up to 15 m/s. The size of the scale model was designed to simulate the behavior of the full scale trajectory control system operating at 20 km altitude. The model confirmed many aspects of trajectory control system performance and the results will be incorporated into future development.

  10. Scientific ballooning in India: recent developments

    NASA Astrophysics Data System (ADS)

    Joshi, M. N.; Damle, S. V.

    The National Scientific Balloon Facility (NBF) of the Tata Institute of Fundamental Research (TIFR) has been conducting regular balloon flights for various experiments in the areas of Space Astronomy and Atmospheric Sciences. A continuous improvement in all aspects of Scientific Ballooning through a sustained R and D programme ensures uptodate services and a better handle on the design specifications for the balloon. Recent developments in balloon grade films, continuous improvements in design specifications, balloon manufacturing methods, flight operational procedures and improved balloon flight capabilities have resulted in a greatly improved flight performance in the last five years. A launch capability upgradation programme in terms of new launch spool and new launch vehicle has been initiated to be able to safely launch balloons with gross lifts upto 3500 kg, balloon volumes upto 450,000 m^3 and payloads upto 1400 kg. A series of steps have been initiated to improve long duration flight capabilities. In this paper, we present details on some of these aspects of Scientific Ballooning in India.

  11. High Altitude Ozone Research Balloon

    NASA Technical Reports Server (NTRS)

    Cauthen, Timothy A.; Daniel, Leslie A.; Herrick, Sally C.; Rock, Stacey G.; Varias, Michael A.

    1990-01-01

    In order to create a mission model of the high altitude ozone research balloon (HAORB) several options for flight preparation, altitude control, flight termination, and payload recovery were considered. After the optimal launch date and location for two separate HAORB flights were calculated, a method for reducing the heat transfer from solar and infrared radiation was designed and analytically tested. This provided the most important advantage of the HAORB over conventional balloons, i.e., its improved flight duration. Comparisons of different parachute configurations were made, and a design best suited for the HAORB's needs was determined to provide for payload recovery after flight termination. In an effort to avoid possible payload damage, a landing system was also developed.

  12. Stratospheric Balloon Gradient Geomagnetic Measurements

    NASA Astrophysics Data System (ADS)

    Filippov, Sergey; Tsvetkov, Yury

    The study of the interior structure of the Earth and laws of its evolution is one of the most difficult problems of natural science. Among the geophysical fields the anomaly magnetic field is one of the most informational in questions of the Earth's crust structure. Many important parameters of an environment are expedient for measuring at lower altitudes, than satellite ones. So, one of the alternatives is stratospheric balloon survey. The balloon flight altitudes cover the range from 20 to 50 km. At such altitudes there are steady zone air flows due to which the balloon flight trajectories can be of any direction, including round-the-world (round-the-pole). One of the examples of such sounding system have been designed, developed and maintained at IZMIRAN during already about 20 years. This system consists of three instrumental con-tainers uniformly placed along a vertical 6 km line. System allows measuring a module and vertical gradient of the geomagnetic field along the whole flight trajectory and so one's name is -stratospheric balloon magnetic gradiometer (SMBG). The GPS-receivers, located in each instrumental container, fix the flight coordinates to within several tens meters. Data trans-mission is carried out by Globalstar satellite link. The obtained data are used in solving the problems of deep sounding of the Earth's crust magnetic structure -an extraction of magnetic anomalies, determination of a depth of bedding of magnetoactive rocks and others. The developed launching technology, deployment in flight, assembly, data processing, transfer and landing the containers with the equipment can be used for other similar problems of monitoring and sounding an environment. Useful flight weights of each instrumental container may be reaching 50 kg. More than ten testing flights (1986-2009) at stratospheric altitudes (20-30 km) have proven the reliability of this system.

  13. 'Transcollateral' Renal Angioplasty for a Completely Occluded Renal Artery

    SciTech Connect

    Chandra, Subash; Chadha, Davinder S. Swamy, Ajay

    2011-02-15

    Percutaneous transluminal renal angioplasty with stenting has been effective in the control of hypertension, renal function, and pulmonary edema caused by atherosclerotic renal artery stenosis. However, the role of the procedure has not been fully established in the context of chronic total occlusion of renal artery. We report the successful use of this procedure in 57-year-old male patient who reported for evaluation of a recent episode of accelerated hypertension. A renal angiogram in this patient showed ostial stenosis of the right renal artery, which was filling by way of the collateral artery. Renal angioplasty for chronic total occlusion of right renal artery was successfully performed in a retrograde fashion through a collateral artery, thereby leading to improvement of renal function and blood pressure control.

  14. [Percutaneous transluminal angioplasty in vascular by-passes].

    PubMed

    Rodríguez, J E; Fernández Guinea, O; López, V; Suárez Pereiro, M J; Reimunde, E; Cosío, J M; Barreiro, A

    1993-01-01

    Results from 21 cases of percutaneous transluminal angioplasties as a treatment of stenosed vascular by-pass from 16 patients, are presented. The technique took place in 10 cases at the aorto-femoral area, in others 10 cases at the popliteal-femoral area and, in the last one, at the carotid-subclavian area. Preliminary results were successful in all cases (100%). Follow-up showed a better long-term results at the aorto-femoral level. Considering the satisfactory results and also considering that, in case of negative results or re-stenosis, other surgical techniques could be performed, we conclude that the percutaneous transluminal angioplasty should be the first treatment for such of injuries.

  15. Deep arterial injury during experimental angioplasty: relation to a positive indium-111-labeled platelet scintigram, quantitative platelet deposition and mural thrombosis

    SciTech Connect

    Lam, J.Y.; Chesebro, J.H.; Steele, P.M.; Dewanjee, M.K.; Badimon, L.; Fuster, V.

    1986-12-01

    Although it is not clear why coronary occlusion and restenosis occur after successful coronary angioplasty, factors related to the procedure may influence early and late results. The possible adverse effects of a medial tear documented histologically and produced during balloon angioplasty of the common carotid arteries were studied in 30 fully heparinized (100 U/kg body weight) normal pigs. Scanning electron microscopy showed endothelial denudation and extensive platelet deposition in all dilated arterial segments. Visible macroscopic mural thrombus was present within an hour of the procedure in 29 (91%) of the 32 arteries that had a medial tear documented by histologic study; the tear produced an indium-111-labeled platelet deposition of 116.4 +/- 26.5 X 10(6)/cm2 (mean +/- SE) and total thrombotic occlusion in 2 arteries (4%). None of the 24 arteries without a medial tear had a thrombus, and the mean platelet deposition in that group was 7.0 +/- 0.5 X 10(6)/cm2 (p less than 0.0008). In 12 pigs scanned with a gamma camera, visible thrombus was associated with platelet deposition in excess of 20 X 10(6)/cm2 in 12 arteries, 9 of which had a positive indium-111-labeled platelet scintigram. Thus, arterial angioplasty causes deep arterial injury, which appears to be a major cause of mural thrombosis, heavy platelet deposition, a positive indium-111-labeled platelet scintigram and acute arterial occlusion. A positive indium-111-labeled platelet scintigram was always associated with macroscopic thrombus of at least 20 > 10(6) platelets/cm2 and underlying deep arterial injury.

  16. Balloon tracer for atmospheric pollutants

    SciTech Connect

    Lichfield, E.W.; Ivey, M.D.; Zak, B.D.; Church, H.W.

    1985-01-01

    An operational prototype of the Balloon Tracer was developed and described. This prototype was designed to be capable of meeting all of the desired specifications for the Balloon Tracer. Its buoyancy adjustment subsystem is shown. Three Gilian instrument pumps operating in parallel provide a flow of about 12 litres per minute, depending upon backpressure. The miniature Klippard mechanical valves are actuated by a servo mechanism which only requires power when the state of the valves is being changed. The balloon itself for the operational prototype is just under 3 meters in diameter. A block diagram of the operational prototype payload measures ambient pressure, temperature, and humidity obtained from AIR which outputs its data in ASCII format. The vertical anemometer, which has a measured starting speed of under 2 cm/s, makes use of a Gill styrofoam propeller and a Spaulding Instruments rotation sendor. The command decoder is built around a chip developed originally for remote control television tuners. The command receiver operating on 13.8035 MHz was developed and built by Hock Engineering. The Argos transmitter is a Telonics platform transmitter terminal. The heart of the control system is an Intel 8052AH BASIC microcomputer with both random access and read only memory.

  17. Viscoelastic behaviour of pumpkin balloons

    NASA Astrophysics Data System (ADS)

    Gerngross, T.; Xu, Y.; Pellegrino, S.

    2008-11-01

    The lobes of the NASA ULDB pumpkin-shaped super-pressure balloons are made of a thin polymeric film that shows considerable time-dependent behaviour. A nonlinear viscoelastic model based on experimental measurements has been recently established for this film. This paper presents a simulation of the viscoelastic behaviour of ULDB balloons with the finite element software ABAQUS. First, the standard viscoelastic modelling capabilities available in ABAQUS are examined, but are found of limited accuracy even for the case of simple uniaxial creep tests on ULDB films. Then, a nonlinear viscoelastic constitutive model is implemented by means of a user-defined subroutine. This approach is verified by means of biaxial creep experiments on pressurized cylinders and is found to be accurate provided that the film anisotropy is also included in the model. A preliminary set of predictions for a single lobe of a ULDB is presented at the end of the paper. It indicates that time-dependent effects in a balloon structure can lead to significant stress redistribution and large increases in the transverse strains in the lobes.

  18. Subclavian artery stenosis treated by transluminal angioplasty: Six cases

    SciTech Connect

    Galichia, J.P.; Bajaj, A.K.; Vine, D.L.; Roberts, R.W.

    1983-06-01

    Transluminal angioplasty (TLA) has been used in six patients with subclavian artery stenosis admitted to a large community hospital. Five patients had lesions proximal to the origin of the left vertebral artery, three of whom had angiographic evidence of subclavian steal syndrome. In all six, arteries were successfully dilated with only one complication of a hematoma at an arteriotomy site. In a 10 to 24-month follow-up, all six patients have remained totally asymptomatic without any further complications.

  19. Basic study of effects on the smooth muscle cells' proliferation with novel short-term thermal angioplasty in vitro and in vivo

    NASA Astrophysics Data System (ADS)

    Kunio, M.; Shimazaki, N.; Ito, A.; Hayashi, T.; Arai, T.; Sakurada, M.

    2011-03-01

    We investigated the effect on smooth muscle cells' proliferation with stretch-fixing in both in vitro and in vivo porcine study to determine the optimum heat condition of novel short-term thermal angioplasty, Photo-thermo Dynamic Balloon Angioplasty (PTDBA). With PTDBA, we have obtained the sufficient arterial dilatation by short-term heating (< 15 s, < 70 °C) and low dilatation pressure (< 0.4 MPa) without excessive neo-intimal hyperplasia on chronic phase. The smooth muscle cells were found to be fixed with stretched shape in vascular wall after PTDBA in vivo. The deformation rate of smooth muscle cells' nuclei was 1.6 +/- 0.1 after PTDBA (15 s, 65 °C, 0.35 MPa). The smooth muscle cells, which were extracted from porcine arteries, were cultured on the specially designed equipment to give stretch-fixing stimulus in vitro. The cell proliferation was inhibited at 20 % stretching compared to 15 % stretching significantly (p < 0.05). The immunostaining specimens of basic Fibroblast Growth Factor (bFGF) and its receptor FGFR-1 were made from the porcine arteries in vivo. We found that the expressions of bFGF and FGFR-1 in the media were not observed after PTDBA. We think that these results suggested the possibility for the inhibition of the excessive cell proliferation after PTDBA.

  20. In vitro angioplasty of atherosclerotic human femoral arteries: analysis of the geometrical changes in the individual tissues using MRI and image processing.

    PubMed

    Auer, Martin; Stollberger, Rudolf; Regitnig, Peter; Ebner, Franz; Holzapfel, Gerhard A

    2010-04-01

    Existing atherosclerotic plaque imaging techniques such as intravascular ultrasound, multidetector computed tomography, optical coherence tomography, and high-resolution magnetic resonance imaging (hrMRI) require computerized methods to separate and analyze the plaque morphology. In this work, we perform in vitro balloon angioplasty experiments with 10 human femoral arteries using hrMRI and image processing. The vessel segments contain low-grade to high-grade lesions with very different plaque compositions. The experiments are designed to mimic the in vivo situation. We use a semi-automatic image processing tool to extract the three-dimensional (3D) geometries of the tissue components at four characteristic stages of the angioplasty procedure. The obtained geometries are then used to determine geometrical and mechanical indices in order to characterize, classify, and analyze the atherosclerotic plaques by their specific geometrical changes. During inflation, three vessels ruptured via helical crack propagation. The adventitia, media, and intima did not preserve their area/volume during inflation; the area changes of the lipid pool during inflation were significant. The characterization of changes in individual 3D tissue geometries, together with tissue-specific mechanical properties, may serve as a basis for refined finite element (FE) modeling, which is key to better understand stress evolution in various atherosclerotic plaque configurations.

  1. Early Results with the Use of Heparin-bonded Stent Graft to Rescue Failed Angioplasty of Chronic Femoropopliteal Occlusive Lesions: TASC D Lesions Have a Poor Outcome

    SciTech Connect

    Kuhan, Ganesh Abisi, Said; Braithwaite, Bruce D.; MacSweeney, Shane T. R.; Whitaker, Simon C.; Habib, Said B.

    2012-10-15

    Purpose: To evaluate early patency rate of the heparin-bonded stent grafts in atherosclerotic long femoropopliteal occlusive disease, and to identify factors that affect outcome. Methods: Heparin-bonded Viabahn stent grafts were placed in 33 limbs in 33 patients during 2009-2010. The stents were deployed to rescue failed conventional balloon angioplasty. Mean age was 69 (range 44-88) years, and 67 % (22 of 33) were men. Most procedures (21 of 33, 64 %) were performed for critical limb ischemia (33 % for rest pain, 30 % tissue loss). Kaplan-Meier plots and Cox regression analysis were used to identify significant risk factors. Results: The average length of lesions treated was 25 {+-} 10 cm, and they were predominantly TASC (Transatlantic Intersociety Consensus) D (n = 13) and C (n = 17) lesions. The median primary patency was 5.0 months (95 % confidence interval 1.22-8.77). The mean secondary patency was 8.6 months (95 % confidence interval 6.82-10.42). Subsequently, 4 patients underwent bypass surgery and 5 patients underwent major amputation. One patient died. There were 5 in-stent or edge-stent stenoses. Cox multivariate regression analysis identified TASC D lesions to be a significant risk factor for early occlusion (p = 0.035). Conclusion: TASC D lesions of femoropopliteal occlusions have poor patency rates with the use of heparin-bonded stent grafts after failed conventional angioplasty. Alternative options should be considered for these patients.

  2. Transluminal coronary angioplasty in the treatment of silent ischemia

    SciTech Connect

    Bergin, P.; Myler, R.K.; Shaw, R.E.; Stertzer, S.H.; Clark, D.A.; Ryan, C.; Murphy, M.C.

    1988-01-01

    Fifty-four asymptomatic patients with positive thallium exercise tests underwent coronary angiography followed by coronary angioplasty (PTCA), as the primary therapy for silent ischemia. The procedure was technically successful in 89% of these patients. Emergency bypass graft surgery was necessary in 2 (3.6%) and q-wave myocardial infarction occurred in 1 (1.8%) of these. All fifty-four patients have been followed for a mean of 35 months since angioplasty. Of the 48 patients with initially successful PTCA, 12 had either clinical restenosis (9/14 or 19%) or a new lesion (3/48 or 6%) during follow-up, which required a repeat PTCA. At the longest follow-up, 46 (85%) had been successfully treated with on or more PTCA procedures. Two patients (3.6%) had sustained late q-wave myocardial infarction and two additional patients reported angina pectoris. There were no deaths. Angioplasty as a primary therapy for silent ischemia appears efficacious, with success and restenosis rates comparable to those in the symptomatic population. Event-free survival is improved, compared with natural history data for patients with silent ischemia from other studies. Prudent risk/benefit analysis may help to define subgroups most likely to benefit from this intervention.

  3. Biodegradable inflatable balloons for tissue separation.

    PubMed

    Basu, Arijit; Haim-Zada, Moran; Domb, Abraham J

    2016-10-01

    Confining radiation to a specific region (during radiation therapy) minimizes damage to surrounding tissues. Biodegradable inflatable balloons (bio-balloons) were developed. The device protects the normal tissues by increasing the gap between radiation source and critical structures. The radiation fades away while passing through the inflated balloon preventing the surrounding tissues from harmful radiation. These bio-balloons have also found clinical use to treat massive rotator cuff tear. This review summarizes the chemistry, engineering, and clinical development of these biomedical devices. These balloons are made of biodegradable polymers folded into the edge of a trocar and inserted between the tissues to be separated, and inflated by normal saline in the site of the application. The inserted balloon protects the tissues from radiation or mechanical stress. They remain inflated on site for two months and are finally eliminated within 12 months.

  4. Balloon-assisted coil placement in wide-neck bifurcation aneurysms by use of a new, compliant balloon microcatheter.

    PubMed

    Baldi, Sebastian; Mounayer, Charbel; Piotin, Michel; Spelle, Laurent; Moret, Jacques

    2003-01-01

    Two types of balloon are usually employed to perform balloon-assisted coil placement in cerebral aneurysms: oval, guide-dependent balloons for sidewall aneurysms and round balloons for bifurcation aneurysms. We report on the use of a new, more compliant, guide-dependent oval balloon microcatheter to seal wide-neck bifurcation aneurysms with coils during endovascular occlusion.

  5. Design considerations for a Martian Balloon Rover

    NASA Technical Reports Server (NTRS)

    Redd, F.; Levesque, R. J.; Williams, G. E.

    1987-01-01

    The present NASA-sponsored design feasibility study for a balloon-borne sensor platform that is to be used over environmentally dissimilar sites on Mars gives attention to specific environmental and configurational parameters of a baseline balloon design, with a view to day/night altitude variations in response to temperature extremes. It is concluded that a Martian Balloon Rover can be developed using current technology; projected reductions in high-strength fabric density and radiation-resistant coatings will further enhance mission effectiveness, permitting either balloon size reductions or payload capacity increases.

  6. Absorption spectrometer balloon flight and iodine investigations

    NASA Technical Reports Server (NTRS)

    1970-01-01

    A high altitude balloon flight experiment to determine the technical feasibility of employing absorption spectroscopy to measure SO2 and NO2 gases in the earth's atmosphere from above the atmospheric ozone layer is discussed. In addition to the balloon experiment the contract includes a ground-based survey of natural I emissions from geological sources and studies of the feasibility of mapping I2 from spacecraft. This report is divided into three major sections as follows: (1) the planning engineering and execution of the balloon experiment, (2) data reduction and analysis of the balloon data, and (3) the results of the I2 phase of the contract.

  7. NASA Langley Research Center tethered balloon systems

    NASA Technical Reports Server (NTRS)

    Owens, Thomas L.; Storey, Richard W.; Youngbluth, Otto

    1987-01-01

    The NASA Langley Research Center tethered balloon system operations are covered in this report for the period of 1979 through 1983. Meteorological data, ozone concentrations, and other data were obtained from in situ measurements. The large tethered balloon had a lifting capability of 30 kilograms to 2500 meters. The report includes descriptions of the various components of the balloon systems such as the balloons, the sensors, the electronics, and the hardware. Several photographs of the system are included as well as a list of projects including the types of data gathered.

  8. [Development of all-silicone detachable balloons].

    PubMed

    Machida, T; Aoki, S; Sasaki, Y; Sasaki, Y; Iio, M; Matsuno, A; Yoshida, S; Basugi, N

    1990-11-25

    Treatment of cerebral vascular lesions such as carotid cavernous sinus fistulas and giant aneurysms is now being performed with intravascular detachable balloon embolization techniques. We have developed several types of all-silicone detachable balloons. Our balloons have self-sealing valves (with or without collars) and detach with simple traction. The self-sealing valve is smaller than 0.6 mm and the balloon can easily be placed through a 7-F catheter. We started clinical trials and a representative case was reported.

  9. Innovative Balloon Buoyancy Techniques for Atmospheric Exploration

    NASA Technical Reports Server (NTRS)

    Jones, J.

    2000-01-01

    Until quite recently, the only practical means to control balloon buoyancy, and thus altitude, required consuming large amounts of fuel or the limited venting of helium balloons and/or dropping of ballast. With recent discoveries at JPL, novel long-life, balloon buoyancy techniques have been discovered that for the first time allow balloons to float in the primarily hydrogen atmospheres of Jupiter, Saturn, Uranus, and Neptune (using ambient fill-gas), and by using renewable energy sources, allow multiple controlled landings on Venus (using atmospheric temperature differences), Mars (solar heat), Titan (RTG heat), and Earth (planet radiant heat).

  10. Efficacy of coronary angioplasty for the treatment of hibernating myocardium

    PubMed Central

    Fath-Ordoubadi, F; Beatt, K; Spyrou, N; Camici, P

    1999-01-01

    OBJECTIVES—To determine the efficacy of coronary angioplasty as the sole method of revascularisation in patients with coronary artery disease and chronically dysfunctional but viable myocardium (hibernating myocardium), and to assess the effect of restenosis on functional outcome.
DESIGN AND PATIENTS—24 consecutive patients with hibernating myocardium were studied. Positron emission tomography was used to assess myocardial viability, blood flow, and flow reserve. One patient refused angioplasty, one had bypass surgery, and one died while waiting for an elective procedure. The procedure failed in three patients. The remaining 18 patients had repeat echocardiography, 15 had repeat coronary angiography, and nine had repeat assessments of blood flow and flow reserve at mean (SD) 17 (2) weeks after angioplasty. In three patients restenosis was documented.
RESULTS—The wall motion score index in the revascularised territories improved from 1.71 (0.37) to 1.34 (0.47) (p = 0.008). Thirty of 51 dysfunctional segments improved in territories without restenosis compared with three of 14 in restenosed territories (p = 0.001). Hibernating and normal segments had comparable flows (0.82 (0.26) v 0.89 (0.24) ml/min/g; NS) while flow reserve was lower in hibernating segments (1.55 (0.68) v 2.07 (1.08); p = 0.03). In segments without restenosis flow reserve improved from 2.03 (1.25) to 2.33 (1.4) (p = 0.03). Sensitivity, specificity, and positive and negative predictive accuracy of the viability study were 97%, 77%, 82%, and 96%, respectively. After excluding patients with restenosis, specificity and positive predictive accuracy improved to 90% and 93%.
CONCLUSIONS—Angioplasty improves function in hibernating myocardium, and restenosis prevents recovery; hibernating myocardium is characterised by an impairment of flow reserve; restenosis affects the diagnostic accuracy of viability studies.


Keywords: coronary artery disease; percutaneous

  11. Scientific Ballooning Activities and Recent Developments in Technology and Instrumentation of the TIFR Balloon Facility, Hyderabad

    NASA Astrophysics Data System (ADS)

    Buduru, Suneel Kumar

    2016-07-01

    The Balloon Facility of Tata Institute of Fundamental Research (TIFR-BF) is a unique center of expertise working throughout the year to design, fabricate and launch scientific balloons mainly for space astronomy, atmospheric science and engineering experiments. Recently TIFR-BF extended its support to new user scientists for conducting balloon launches for biological and middle atmospheric sciences. For the first time two balloon launches conducted for sending live lab rats to upper stratosphere and provided launch support for different balloon campaigns such as Tropical Tropopause Dynamics (TTD) to study water vapour content in upper tropospheric and lower stratospheric regions over Hyderabad and the other balloon campaign to study the Asian Tropopause Aerosol Layer (BATAL) during the Indian summer monsoon season. BATAL is the first campaign to conduct balloon launches during active (South-West) monsoon season using zero pressure balloons of different volumes. TIFR-BF also provided zero pressure and sounding balloon support to various research institutes and organizations in India and for several international space projects. In this paper, we present details on our increased capability of balloon fabrication for carrying heavier payloads, development of high strength balloon load tapes and recent developments of flight control and safety systems. A summary of the various flights conducted in two years will be presented along with the future ballooning plans.

  12. Reduction of intimal hyperplasia in injured rat arteries promoted by catheter balloons coated with polyelectrolyte multilayers that contain plasmid DNA encoding PKCδ.

    PubMed

    Bechler, Shane L; Si, Yi; Yu, Yan; Ren, Jun; Liu, Bo; Lynn, David M

    2013-01-01

    New therapeutic approaches that eliminate or reduce the occurrence of intimal hyperplasia following balloon angioplasty could improve the efficacy of vascular interventions and improve the quality of life of patients suffering from vascular diseases. Here, we report that treatment of arteries using catheter balloons coated with thin polyelectrolyte-based films ('polyelectrolyte multilayers', PEMs) can substantially reduce intimal hyperplasia in an in vivo rat model of vascular injury. We used a layer-by-layer (LbL) process to coat the surfaces of inflatable catheter balloons with PEMs composed of nanolayers of a cationic poly(β-amino ester) (polymer 1) and plasmid DNA (pPKCδ) encoding the δ isoform of protein kinase C (PKCδ), a regulator of apoptosis and other cell processes that has been demonstrated to reduce intimal hyperplasia in injured arterial tissue when administered via perfusion using viral vectors. Insertion of balloons coated with polymer 1/pPKCδ multilayers into injured arteries for 20 min resulted in local transfer of DNA and elevated levels of PKCδ expression in the media of treated tissue three days after delivery. IFC and IHC analysis revealed these levels of expression to promote downstream cellular processes associated with up-regulation of apoptosis. Analysis of arterial tissue 14 days after treatment revealed polymer 1/pPKCδ-coated balloons to reduce the occurrence of intimal hyperplasia by ~60% compared to balloons coated with films containing empty plasmid vectors. Our results demonstrate the potential therapeutic value of this nanotechnology-based approach to local gene delivery in the clinically important context of balloon-mediated vascular interventions. These PEM-based methods could also prove useful for other in vivo applications that require short-term, surface-mediated transfer of plasmid DNA.

  13. Low-cost balloon missions to Mars and Venus

    NASA Technical Reports Server (NTRS)

    Kerzhanovich, V.; Cutts, J.; Hall, J.

    2003-01-01

    The first successful flight demonstration of aerial deployment of Mars balloon prototypes in June 2002 and, earlier, of Venus balloon prototype deemed to be a turning point in the risk assessment of balloon missions.

  14. Paclitaxel-Coated Balloons: Review of a Promising Interventional Approach to Preventing Restenosis in Femoropopliteal Arteries.

    PubMed

    Teleb, Mohamed; Wardi, Miraie; Gosavi, Sucheta; Said, Sarmad; Mukherjee, Debabrata

    2016-06-01

    Peripheral arterial disease (PAD), a major cause of morbidity and mortality worldwide, is characterized by intermittent claudication and is associated with chronic diseases such as diabetes and hypertension. The goal of treatment is to address the underlying cause and to modify risk factors. Although medical management is the first-line treatment of PAD, some individuals may have severe symptoms and require revascularization with percutaneous transluminal angioplasty with or without stent placement or surgery. Interventional approaches may, however, be associated with high prevalence of restenosis and subsequent complications such as critical limb ischemia and amputation. Drug-eluting balloons (DEBs) are a new interventional technology with the primary goal of preventing restenosis. We review the clinical trials and studies that assessed the efficacy and safety profile of DEB and will focus on the restenosis rate in femoropopliteal arteries including target lesion revascularization (TLR) and late lumen lesion (LLL) using different modalities of intervention such as stents and DEB. Average data collected from the trials reported included restenosis rate of 25%, 0.3 mm LLL, and 14% reduction in TLR with DEB versus uncoated balloons. Below the knee (BTK) only intervention studies were excluded from this review as endovascular approach is usually reserved for critical limb ischemia for BTK disease. Interventional approach to treat PAD with DEB appears to be a promising technology. Additional larger studies are needed to further define safety, efficacy, and longer term outcome with this novel technology.

  15. Intragastric Balloons in Clinical Practice.

    PubMed

    Papademetriou, Marianna; Popov, Violeta

    2017-04-01

    Cost-effective therapies to address the growing epidemic of obesity are a leading priority in modern medicine. Intragastric balloons (IGBs) are one such option, with increased effectiveness compared with pharmacotherapy and lifestyle and a lower rate of adverse events than bariatric surgery. IGBs are endoscopically placed or swallowed space-occupying devices in the stomach. Three IGB systems were approved in 2015 to 2016 by the Food and Drug Administration for use in the United States, with more devices nearing approval. This paper reviews the adverse events and efficacy of IGBs, and practice setup, management of common complications, and dietary advice for patients.

  16. Novel adjunctive treatments of myocardial infarction

    PubMed Central

    Schmidt, Michael Rahbek; Pryds, Kasper; Bøtker, Hans Erik

    2014-01-01

    Myocardial infarction is a major cause of death and disability worldwide and myocardial infarct size is a major determinant of prognosis. Early and successful restoration of myocardial reperfusion following an ischemic event is the most effective strategy to reduce final infarct size and improve clinical outcome, but reperfusion may induce further myocardial damage itself. Development of adjunctive therapies to limit myocardial reperfusion injury beyond opening of the coronary artery gains increasing attention. A vast number of experimental studies have shown cardioprotective effects of ischemic and pharmacological conditioning, but despite decades of research, the translation into clinical effects has been challenging. Recently published clinical studies, however, prompt optimism as novel techniques allow for improved clinical applicability. Cyclosporine A, the GLP-1 analogue exenatide and rapid cooling by endovascular infusion of cold saline all reduce infarct size and may confer clinical benefit for patients admitted with acute myocardial infarcts. Equally promising, three follow-up studies of the effect of remote ischemic conditioning (RIC) show clinical prognostic benefit in patients undergoing coronary surgery and percutaneous coronary intervention. The discovery that RIC can be performed noninvasively using a blood pressure cuff on the upper arm to induce brief episodes of limb ischemia and reperfusion has facilitated the translation of RIC into the clinical arena. This review focus on novel advances in adjunctive therapies in relation to acute and elective coronary procedures. PMID:24976915

  17. Adjunct therapy for type 1 diabetes mellitus.

    PubMed

    Lebovitz, Harold E

    2010-06-01

    Insulin replacement therapy in type 1 diabetes mellitus (T1DM) is nonphysiologic. Hyperinsulinemia is generated in the periphery to achieve normal insulin concentrations in the liver. This mismatch results in increased hypoglycemia, increased food intake with weight gain, and insufficient regulation of postprandial glucose excursions. Islet amyloid polypeptide is a hormone synthesized in pancreatic beta cells and cosecreted with insulin. Circulating islet amyloid polypeptide binds to receptors located in the hindbrain and increases satiety, delays gastric emptying and suppresses glucagon secretion. Thus, islet amyloid polypeptide complements the effects of insulin. T1DM is a state of both islet amyloid polypeptide and insulin deficiency. Pramlintide, a synthetic analog of islet amyloid polypeptide, can replace this hormone in patients with T1DM. When administered as adjunctive therapy to such patients treated with insulin, pramlintide decreases food intake and causes weight loss. Pramlintide therapy is also associated with suppression of glucagon secretion and delayed gastric emptying, both of which decrease postprandial plasma glucose excursions. Pramlintide therapy improves glycemic control and lessens weight gain. Agents that decrease intestinal carbohydrate digestion (alpha-glucosidase inhibitors) or decrease insulin resistance (metformin) might be alternative adjunctive therapies in T1DM, though its benefits are marginally supported by clinical data.

  18. Treatment of symptomatic intracranial atherosclerotic stenosis with a normal-sized Gateway(™) balloon and Wingspan(™) stent.

    PubMed

    Yu, J; Wang, L; Deng, J P; Gao, L; Zhang, T; Zhao, Z W; Gao, G D

    2010-01-01

    The safety and performance of angioplasty using a normal-sized Gateway(™) balloon and Wingspan(™) stent for intracranial atherosclerotic stenosis were assessed. Seventy-two patients with intracranial stenosis (≥ 50%) were treated using an undersized (group U) or normal-sized (group N) Gateway(™) balloon and a Wingspan(™) stent. All patients were successfully stented. Stenosis improved from 74.2% before treatment to 23.8% immediately after treatment in group U and from 70.9% to 20.1% in group N. The two groups had similar rates of major periprocedural neurological complications (9.0% overall), none of which led to death. Residual stenosis at follow-up was 40.8% and 32.5% in groups U and N, respectively. In-stent re-stenosis (ISR) was significantly less frequent in group N (22.0%) than in group U (33.3%). It is concluded that use of a normal-sized Gateway(™) balloon and Wingspan(™) stent appears to be safe, to have a high rate of technical success, good immediate post-operative results and a low ISR rate.

  19. Power supplies for long duration balloon flights

    NASA Astrophysics Data System (ADS)

    Lichfield, Ernest W.

    Long duration balloon flights require more electrical power than can be carried in primary batteries. This paper provides design information for selecting rechargeable batteries and charging systems. Solar panels for recharging batteries are discussed, with particular emphasis on cells mounting suitable for balloon flights and panel orientation for maximum power collection. Since efficient utilization of power is so important, modern DC to DC power conversion techniques are presented. On short flights of 1 day or less, system designers have not been greatly concerned with battery weight. But, with the advent of long duration balloon flights using superpressure balloons, anchor balloon systems, and RACOON balloon techniques, power supplies and their weight become of prime importance. The criteria for evaluating power systems for long duration balloon flights is performance per unit weight. Instrumented balloon systems have flown 44 days. For these very long duration flights, batteries recharged from solar cells are the only solution. For intermediate flight duration, say less than 10 days, the system designer should seriously consider using primary cells. The National Center for Atmospheric Research is sponsored by the National Science Foundation. Any opinions, findings and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the National Science Foundation.

  20. 21 CFR 874.4100 - Epistaxis balloon.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Epistaxis balloon. 874.4100 Section 874.4100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4100 Epistaxis balloon. (a)...

  1. 21 CFR 874.4100 - Epistaxis balloon.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Epistaxis balloon. 874.4100 Section 874.4100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4100 Epistaxis balloon. (a)...

  2. 21 CFR 874.4100 - Epistaxis balloon.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Epistaxis balloon. 874.4100 Section 874.4100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4100 Epistaxis balloon. (a)...

  3. [Percutaneous angioplasty (PTA) in the treatment of non-penetrating injuries to the subclavian artery. A clinical case].

    PubMed

    Giordanengo, F; Boneschi, M; Giorgetti, P L; Lovaria, A

    1996-05-01

    Non penetrating injuries to the subclavian vessels are uncommon. We present a case of a young patient with an isolated blunt trauma of the right subclavian artery. The patient, a 25 year-old woman, was admitted to our Institute after a motor-vehicle accident, with a physical findings of absent peripheral pulses and right clavicular fracture, confirmed by non-invasive vascular evaluation and X-ray of the chest. Diagnosis was established by an urgent selective angiography that showed a subintimal hematoma with occlusion of the vessel and peripheral ischemia of the arm. The patient clinical status (hemodynamically stable) permitted a conservative management and a transluminal percutaneous angioplasty (PTA) with a trans-femoral catheter balloon. After radiologic treatment, the patient showed good palpable peripheral pulses. Clavicular fracture was treated by esternal stabilization. We believe that in selected patients, without other serious life-threatening injures, the intimal artery injury can be treated by a conservative and now also radiologic Therapy; PTA treatment avoids morbidity and mortality associated with surgical intervention.

  4. Intra-aortic balloon pumps.

    PubMed

    1997-05-01

    Intra-aortic balloon pumps (IABPs) are circulatory assist devices used to treat a number of cardiovascular conditions. IABPs provide temporary circulatory support by reducing the resistance to blood flow out of the heart during systole and by providing added pressure to aid in perfusing the heart during diastole. In this Evaluation, we tested three IABPs from three suppliers. We examined the units' technical performance, safety and monitoring, human factors design, transport operation, and supplier support. Rather than test all the triggering (activation) modes available, we focused our testing on the modes most commonly used on each unit. We also provide information on an IABP currently available only in Japan; although we did not test this unit, we do provide a preliminary judgment based on the information provided to us by the supplier. In the Technology Overview also included in the Evaluation, we describe the basic operation and use of an IABP, as well as review the state of the art of this technology. And in the Selection, Purchasing, and Use Guide at the conclusion of the Evaluation, we discuss such topics as balloon costs and sizing, interfacing IABPs with patient monitors, and the use of IABPs in community hospitals.

  5. Platelet-derived growth factor promotes smooth muscle migration and intimal thickening in a rat model of balloon angioplasty.

    PubMed Central

    Jawien, A; Bowen-Pope, D F; Lindner, V; Schwartz, S M; Clowes, A W

    1992-01-01

    Platelet-derived growth factor (PDGF) is a mitogen and chemoattractant for vascular smooth muscle cells (SMC) in vitro, but its activities in vivo remain largely undefined. We infused recombinant PDGF-BB (0.01-0.30 mg/kg per d i.v.) into rats subjected to carotid injury. PDGF-BB produced a small increase (two- to threefold) in medial SMC proliferation. More importantly, PDGF-BB greatly increased (20-fold) the intimal thickening and the migration of SMC from the media to the intima during the first 7 d after injury. These data provide support for the hypothesis that PDGF, and perhaps other platelet factors, might play an important role in the movement of mesenchymal cells into zones of injury undergoing repair. Images PMID:1531345

  6. Infrapopliteal angioplasty using a combined angiosomal reperfusion strategy

    PubMed Central

    Ambler, G. K.; Stimpson, A. L.; Wardle, B. G.; Hanif, U. K.; Germain, S.; Chick, C.; Goyal, N.; Twine, C. P.

    2017-01-01

    Introduction Infra-popliteal angioplasty continues to be widely performed with minimal evidence to guide practice. Endovascular device selection is contentious and there is even uncertainty over which artery to treat for optimum reperfusion. Direct reperfusion (DR) targets the artery supplying the ischaemic tissue. Indirect reperfusion (IR) targets an artery supplying collaterals to the ischaemic area. Our unit practice for the last eight years has been to attempt to open all tibial arteries at the time of angioplasty. When successful, this results in both direct and indirect; or combined reperfusion (CR). The aim was to review the outcomes of CR and compare them with DR or IR alone. Methods An eight year retrospective review from a single unit of all infra-popliteal angioplasties was undertaken. Wound healing, limb salvage, amputation-free and overall survival data as well as re-intervention rates were captured for all patients. Subgroup analysis for diabetics was undertaken. Kaplan Meier curves are presented for survival outcomes. All odds and hazard ratios (HR) and p values were corrected for bias from confounders using multivariate analysis. Results 250 procedures were performed: 22 (9%) were CR; 115 (46%) DR and 113 (45%) IR. Amputation-free survival (HR 0.504, p = 0.039) and re-intervention and amputation-free survival (HR 0.414, p = 0.005) were significantly improved in patients undergoing CR compared to IR. Wound healing was similarly affected by reperfusion strategy (OR = 0.35, p = 0.047). Effects of CR over IR were similar when only diabetic patients were considered. Conclusions Combined revascularisation can only be achieved in approximately 10% of patients. However, when successful, it results in significant improvements in wound healing and amputation-free survival over simple indirect reperfusion techniques. PMID:28199363

  7. The novel drug delivery to vascular wall using laser driven thermal balloon: basic study ex vivo

    NASA Astrophysics Data System (ADS)

    Suganuma, Kao; Homma, Rie; Shimazaki, Natsumi; Ogawa, Emiyu; Arai, Tsunenori

    2016-10-01

    To enhance drug delivery performance of popular drug eluting balloon against re-stenosis after angioplasty, we have an idea regarding to adjacent use of our unique laser driven thermal balloon of which characteristics could realize short term and uniform temperature elevation to modify drug delivery characteristics. We have already reported a delivery enhancement effect using this idea, however, detailed characteristics have not been studied yet. We studied balloon dilatation in terms of vascular circumferential tension on the heating drug delivery performance using porcine carotid artery wall ex vivo. The extracted carotid artery was used and circumferential tension of 0-30 mN/mm2 was added. Heating drug delivery was performed on this carotid artery with the heated solution of hydrophobic fluorescent Rhodamine B with 3 μg/ml in concentration at 37 and 70°C. We obtained a defined drug delivery quantity as well as delivery depth by a microscopic fluorescence measurement on a cross section of the drug delivered vessel wall. In the cases of 70°C, we found the drug penetration increase against 3°C case. We predict that the collagen thermal denaturation of the vessel wall may play important role to this penetration. In the case of 3°C, we found the drug concentration on the intimal surface with 7 mN/mm2 was increased as 10-30 times as other tension values. We found surface grooves in this case using an electron micrography. Therefore, we think that the drug delivery enhancement might be related to the groove formations of the vessel wall.

  8. Promising role of drug-coated balloons in the tibial vessels?

    PubMed

    Langhoff, Ralf; Behne, Andrea; Buschmann, Eva E

    2016-06-22

    To judge on the role of drug-coated balloons (DCB) in below-the-knee (BTK) artery interventions, we analyzed randomized trials which compare coated to non-coated balloons and additionally a direct comparison of drug-eluting stents (DES) with DCB. As angioplasty with non-coated balloons is per guideline-recommendation still standard of care for below- the-knee artery endovascular treatment, we focused on the direct comparison of efficacy and clinical outcome data of both treatment modalities. Data from peer reviewed and published trials were consulted. For each single study, primary and secondary endpoints were reported and compared. Three single-center, non-core lab adjudicated trials showed encouraging data which suggests that DCB in BTK arteries effectively inhibit the risk of early restenosis, but the pivotal, prospectively randomized, multicenter, core lab adjudicated trials failed to match with these result. Limitations of DEB treatment and trials in BTK arteries had been reported, hence a technical evaluation of possible side effects of DCB treatment and of trial design was taken into account. On the basis of the results available, the distinguishing findings of drug eluting effects in the femoropopliteal region cannot be transferred to BTK arteries. Refinement of the existing DCB technology and of future trial design should be considered. To adjudicate on DCB technology applied for BTK treatment is premature and it is mandatory to be kept under evaluation, because the potential benefit, with respect to the compelling results in the femoropoliteal arteries, could be huge to improve endovascular BTK and especially CLI treatment.

  9. Promising role of drug-coated balloons in the tibial vessels?

    PubMed

    Langhoff, Ralf; Behne, Andrea; Buschmann, Eva

    2016-10-01

    In order to assess the role of drug-coated balloons (DCB) in below-the-knee (BTK) artery interventions, we analyzed randomized trials which compare coated to non-coated balloons and additionally a direct comparison of drug-eluting stents (DES) with DCB. As angioplasty with non-coated balloons is per guideline-recommendation still standard of care for below-the-knee artery endovascular treatment, we focused on the direct comparison of efficacy and clinical outcome data of both treatment modalities. Data from peer reviewed and published trials were consulted. For each single study, primary and secondary endpoints were reported and compared. Three single-center, non-core lab adjudicated trials showed encouraging data which suggests that DCB in BTK arteries effectively inhibit the risk of early restenosis, but the pivotal, prospectively randomized, multicenter, core lab adjudicated trials failed to match with these result. Limitations of DEB treatment and trials in BTK arteries had been reported, hence a technical evaluation of possible side effects of DCB treatment and of trial design was taken into account. On the basis of the results available, the distinguishing findings of drug eluting effects in the femoropopliteal region cannot be transferred to BTK arteries. Refinement of the existing DCB technology and of future trial design should be considered. To adjudicate on DCB technology applied for BTK treatment is premature and it is mandatory to be kept under evaluation, because the potential benefit, with respect to the compelling results in the femoropoliteal arteries, could be huge to improve endovascular BTK and especially CLI treatment.

  10. Percutaneous Transluminal Angioplasty in Peripheral Vascular Disease: A Review

    PubMed Central

    Louis, Eugene L. St.; Provan, John L.; Gray, Robin R.; Grosman, Harvey; Ameli, F. Michael; Elliott, David S.

    1982-01-01

    Percutaneous transluminal angioplasty is a relatively new technique employed in the treatment of stenoses or occlusions of peripheral arteries. While the longterm success rates have yet to be determined, short-term results have been excellent. The procedure has greatest value in the dilatation of localized lesions, avoiding surgery and its attendant risks. However, PTA and surgery are complementary, not competing, modes of therapy. PTA complements the traditional therapy of peripheral vascular disease, which remains reconstructive surgery. ImagesFig. 7Fig. 8Fig. 9Fig. 10Fig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6 PMID:21286052

  11. A Philosopher Stirs up the World of Adjuncts

    ERIC Educational Resources Information Center

    June, Audrey Williams

    2008-01-01

    Keith Hoeller is an adjunct professor. He teaches philosophy for a living at Green River Community College, just outside Seattle. He has also spent much of the last two decades ruminating about the bigger picture for those at his level of the professorial pecking order. Over the years, Hoeller has lobbied relentlessly for adjunct-friendly…

  12. The Benefits and Barriers of Virtual Collaboration among Online Adjuncts

    ERIC Educational Resources Information Center

    Schieffer, Lori

    2016-01-01

    Online education is a current trend in higher education. This has left colleges needing to hire more part-time remote adjuncts to fill the fluctuating number of available courses. Because remote online adjuncts are susceptible to isolation, the need has arisen to study the benefits and barriers of virtual collaboration. The purpose of this…

  13. 32 CFR 728.93 - Chart of adjuncts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL MEDICAL AND DENTAL CARE FOR ELIGIBLE PERSONS AT NAVY MEDICAL DEPARTMENT FACILITIES Adjuncts to Medical Care § 728.93 Chart of... the several categories of beneficiaries eligible for medical care at naval MTFs. Adjuncts Active...

  14. 29 CFR 780.617 - Adjunct livestock auction operations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Adjunct livestock auction operations. 780.617 Section 780... Employment in Agriculture and Livestock Auction Operations Under the Section 13(b)(13) Exemption Requirements for Exemption § 780.617 Adjunct livestock auction operations. The livestock auction...

  15. Psychotherapeutic and Adjunctive Pharmacologic Approaches to Treating Posttraumatic Stress Disorder

    PubMed Central

    Nisenoff, Carolina D.

    2008-01-01

    Posttraumatic stress disorder (PTSD) is a potentially disabling illness that affects millions of people worldwide and can be very difficult to treat, especially the sleep disturbances often associated with this disorder. Successful treatment focuses on psychotherapy, and medications may be useful adjuncts. This article gives examples of successful therapeutic approaches and adjunctive medication use in PTSD. PMID:19727267

  16. Ecological Validity of Adjunct Questions in a College Biology Course.

    ERIC Educational Resources Information Center

    Spring, Carl; And Others

    1986-01-01

    To validate their use in a natural environment with realistic learning materials and conditions, the efficacy of adjunct questions was tested in a college biology course with a double-crossover design. Mixed results were obtained. It is concluded that it would be better to make adjunct questions optional. (Author/LMO)

  17. The Accidental Faculty: Adjunct Instructors in Community Colleges.

    ERIC Educational Resources Information Center

    Ellison, Alicia B.

    In 1998, the proportion of full-time faculty at U.S. community colleges was reported to be 36%, versus 64% part time. Adjunct faculty are attractive to community colleges primarily because they provide low-cost labor. The conditions under which many community college adjunct faculty work can contribute to their marginalization as a kind of…

  18. Exploring the Experiences of Women Adjunct Faculty: A Phenomenology

    ERIC Educational Resources Information Center

    Cross, Emily L.

    2013-01-01

    This qualitative phenomenological study was designed to give an in-depth understanding of the lived experiences of women adjunct faculty working at a mid-sized community college in California. A review of literature surrounding adjunct faculty, community colleges, and women in higher education found a gap in the exploration and discussion of…

  19. The protective effect of bergamot oil extract on lecitine-like oxyLDL receptor-1 expression in balloon injury-related neointima formation.

    PubMed

    Mollace, Vincenzo; Ragusa, Salvatore; Sacco, Iolanda; Muscoli, Carolina; Sculco, Francesca; Visalli, Valeria; Palma, Ernesto; Muscoli, Saverio; Mondello, Luigi; Dugo, Paola; Rotiroti, Domenicantonio; Romeo, Francesco

    2008-06-01

    Lectin-like oxyLDL receptor-1 (LOX-1) has recently been suggested to be involved in smooth muscle cell (SMC) proliferation and neointima formation in injured blood vessels. This study evaluates the effect of the nonvolatile fraction (NVF), the antioxidant component of bergamot essential oil (BEO), on LOX-1 expression and free radical generation in a model of rat angioplasty. Common carotid arteries injured by balloon angioplasty were removed after 14 days for histopathological, biochemical, and immunohistochemical studies. Balloon injury led to a significant restenosis with SMC proliferation and neointima formation, accompanied by increased expression of LOX-1 receptor, malondialdehyde and superoxide formation, and nitrotyrosine staining. Pretreatment of rats with BEO-NVF reduced the neointima proliferation together with free radical formation and LOX-1 expression in a dose-dependent manner. These results suggest that natural antioxidants may be relevant in the treatment of vascular disorders in which proliferation of SMCs and oxyLDL-related endothelial cell dysfunction are involved.

  20. Cerebrospinal Fluid Enhancement on Fluid Attenuated Inversion Recovery Images After Carotid Artery Stenting with Neuroprotective Balloon Occlusions: Hemodynamic Instability and Blood-Brain Barrier Disruption

    SciTech Connect

    Ogami, Ryo Nakahara, Toshinori; Hamasaki, Osamu; Araki, Hayato; Kurisu, Kaoru

    2011-10-15

    Purpose: A rare complication of carotid artery stenting (CAS), prolonged reversible neurological symptoms with delayed cerebrospinal fluid (CSF) space enhancement on fluid attenuated inversion recovery (FLAIR) images, is associated with blood-brain barrier (BBB) disruption. We prospectively identified patients who showed CSF space enhancement on FLAIR images. Methods: Nineteen patients-5 acute-phase and 14 scheduled-underwent 21 CAS procedures. Balloon catheters were navigated across stenoses, angioplasty was performed using a neuroprotective balloon, and stents were placed with after dilation under distal balloon protection. CSF space hyperintensity or obscuration on FLAIR after versus before CAS indicated CSF space enhancement. Correlations with clinical factors were examined. Results: CSF space was enhanced on FLAIR in 12 (57.1%) cases. Postprocedural CSF space enhancement was significantly related to age, stenosis rate, acute-stage procedure, and total occlusion time. All acute-stage CAS patients showed delayed enhancement. Only age was associated with delayed CSF space enhancement in scheduled CAS patients. Conclusions: Ischemic intolerance for severe carotid artery stenosis and temporary neuroprotective balloon occlusion, causing reperfusion injury, seem to be the main factors that underlie BBB disruption with delayed CSF space enhancement shortly after CAS, rather than sudden poststenting hemodynamic change. Our results suggest that factors related to hemodynamic instability or ischemic intolerance seem to be associated with post-CAS BBB vulnerability. Patients at risk for hemodynamic instability or with ischemic intolerance, which decrease BBB integrity, require careful management to prevent intracranial hemorrhagic and other post-CAS complications.

  1. Adjunctive pregabalin vs gabapentin for focal seizures

    PubMed Central

    Glue, Paul; Friedman, Daniel; Almas, Mary; Yardi, Nandan; Knapp, Lloyd; Pitman, Verne; Posner, Holly B.

    2016-01-01

    Objective: To evaluate the comparative safety and adjunctive efficacy of pregabalin and gabapentin in reducing seizure frequency in patients with partial-onset seizures based on prestudy modeling showing superior efficacy for pregabalin. Methods: The design of this comparative efficacy and safety study of pregabalin and gabapentin as adjunctive treatment in adults with refractory partial-onset seizures was randomized, flexible dose, double blind, and parallel group. The study included a 6-week baseline and a 21-week treatment phase. The primary endpoint was the percentage change from baseline in 28-day seizure rate to the treatment phase. Results: A total of 484 patients were randomized to pregabalin (n = 242) or gabapentin (n = 242). Of these, 359 patients (187 pregabalin, 172 gabapentin) completed the treatment phase. The observed median and mean in percentage change from baseline was −58.65 and −47.7 (SD 48.3) for pregabalin and −57.43 and −45.28 (SD 60.6) for gabapentin. For the primary endpoint, there was no significant difference between treatments. The Hodges-Lehman estimated median difference was 0.0 (95% confidence interval −6.0 to 7.0). Safety profiles were comparable and consistent with prior trials. Conclusions: The absence of the anticipated efficacy difference based on modeling of prior, nearly identical trials and the larger-than-expected response rates of the 2 antiepileptic drugs were unexpected. These findings raise questions that are potentially important to consider in future comparative efficacy trials. ClinicalTrials.gov identifier: NCT00537940. Classification of evidence: This study provides Class II evidence that for patients with partial seizures enrolled in this study, pregabalin is not superior to gabapentin in reducing seizure frequency. Because of the atypical response rates, the results of this study are poorly generalizable to other epilepsy populations. PMID:27521437

  2. All Adjuncts Are Not Created Equal: An Exploratory Study of Teaching and Professional Needs of Online Adjuncts

    ERIC Educational Resources Information Center

    Bedford, Laurie; Miller, Heather

    2013-01-01

    Online education programs continue to rely on a significant contingent of adjunct faculty to meet the instructional needs of the students. Discourse relating to this situation primarily focuses on the extent to which adjuncts are able to ensure the rigor and quality of instruction as well as the ability of the organization to attract, retain, and…

  3. A Low-Cost Sounding Balloon Experiment

    NASA Astrophysics Data System (ADS)

    Saba, Marcelo M. F.; Mirisola, Luiz G. B.; Iguchi, Marcio

    2005-12-01

    Watching the meteorological balloons customarily launched from our city, we wondered how we could develop an experiment to allow our students to effectively gather data about the low atmosphere and at the same time ke6ep our limited financial budget. When you hear about atmospheric balloons, you usually think about balloons with large envelopes of nylon or mylar with payloads between 1 or 10 kg. They ascend to very high altitudes, have a data radio transmitter, and are not recoverable. This setup would be too expensive for us. In order to keep the cost low, the payload containing the data recorded had to be recovered, and therefore, the balloon must not go tens of kilometers away. We ruled out tethered balloons, which would not have recovery problems but can hardly go beyond 100 m high because of the weight of the tether and of lateral winds. Based on some estimates of ascension speed for small balloons and probable horizontal wind intensities, we decided that in order to easily recover the payload we had to limit its ascension to about 2 km high. At this altitude, the payload would have to be released from the balloon by means of a timer.

  4. Fracture characteristics of balloon films

    NASA Technical Reports Server (NTRS)

    Portanova, Marc A.

    1989-01-01

    An attempt was made to determine the failure modes of high altitude scientific balloons through an investigation of the fracture characteristics of the thin polyethylene films. Two films were the subject of the evaluation, Winzen Int.'s Stratafilm SF-85 and Raven Industries' Astro-E. Research began with an investigation of the film's cold brittleness point and it's effect on the ultimate strength and elasticity of the polyethylene film. A series of preliminary investigations were conducted to develop an understanding of the material characteristics. The primary focus of this investigation was on the notch sensitivity of the films. Simple stress strain tests were also conducted to enable analysis employing fracture toughness parameters. Studies were conducted on both film types at 23 C (room temperature), -60 C, -90 C, and -120 C.

  5. The testing of balloon fabrics

    NASA Technical Reports Server (NTRS)

    Edwards, Junius David; Moore, Irwin L

    1920-01-01

    Report describes methods and materials used in waterproofing and fireproofing airplane fabrics using dopes. The determination of the probable life of a balloon fabric in service by experimental means is of great value in choosing the most suitable fabrics for a given purpose and in pointing the way to improvements in compounding and construction. The usefulness of exposure to the weather for this purpose has been amply demonstrated. Various attempts have been made to reproduce by artificial means the conditions promoting deterioration in service, but without marked success. Exposure to the weather remains the most satisfactory method for this purpose, and a consideration of the characteristics of such tests is therefore important. This report presents the results of a typical series of exposure tests made in 1917.

  6. Clinical experience with ultrasound guided angioplasty for vascular access

    PubMed Central

    Cho, Seong; Lee, Yu-Ji; Kim, Sung-Rok

    2017-01-01

    Background The use of ultrasound guided percutaneous transluminal angioplasty (UG-PTA), which use ultrasound as an imaging modality, is an evolving strategy. But, in Korea, this method is rarely used. We report our experiences with UG-PTA with respect to technical success rates and complication rates compared to conventional PTA (C-PTA), performed between 2010 and 2015 at Samsung Changwon Hospital, Korea. Methods In our series, 53 cases of UG-PTA and 90 cases of C-PTA were reviewed, respectively. Cases of central vein stenosis, cephalic arch stenosis, arterial stenosis and thrombosis were excluded. However, cases of juxta-anastomotic stenosis and outflow vein stenosis were included. Results Technical success was achieved in 96.2% (51 of 53) of cases in the UG-PTA group and in 93.3% (84 of 90) of cases in the C-PTA group, respectively (P = 0.710). Technical failure was experienced in a total 8 cases (UG-PTA group: 2/53, 3.8%; C-PTA group: 6/90, 6.7%). No differences were observed in complications. Conclusion Duplex ultrasound-guided angioplasty for dialysis access in the outpatient setting is feasible, safe, and effective for peripheral venous stenotic lesions. It offers many advantages over conventional angiographic procedures, and, in the future, it has great potential to play a significant role in the management of these challenging patients. PMID:28393000

  7. Early Results of Retrograde Transpopliteal Angioplasty of Iliofemoral Lesions

    SciTech Connect

    Saha, Saumitra; Gibson, Matthew; Magee, Timothy R.; Galland, Robert B.; Torrie, E. Peter H.

    2001-12-15

    Purpose: To assess whether the retrograde transpopliteal approach is a safe, practical and effective alternative to femoral puncture for percutaneous transluminal angioplasty (PTA).Methods: Forty PTAs in 38 patients were evaluated. Intentional subintimal recanalization was performed in 13 limbs. Ultrasound evaluation of the popliteal fossa was carried out 30 min and 24 hr post procedurally in the first 10 patients to exclude local complications. All patients had a follow-up of at least 6 weeks.Results: The indication for PTA was critical ischemia in seven limbs and disabling claudication in the remainder.Stenoses (single or multiple) were present in 24 and occlusion in 15.The superficial femoral artery (SFA) was the commonest segment affected(36) followed by common femoral artery (CFA) in four and iliac artery in four. Technical success was achieved in 38 of 39 limbs where angioplasty was carried out. In one limb no lesion was found.Immediate complications were distal embolization in two and thrombosis in one. None of these required immediate surgery. There were no puncture site hematomas or popliteal arteriovenous fistulae.Symptomatic patency at 6 weeks was 85%. Further reconstructive surgery was required in three limbs and amputation in two.Conclusion: The transpopliteal approach has a high technical success rate and a low complication rate with a potential to develop into an outpatient procedure. It should be considered for flush SFA occulsions or iliac disease with tandem CFA/SFA disease where the contralateral femoral approach is often technically difficult.

  8. Resistance to Clopidogrel among Iranian Patients Undergoing Angioplasty Intervention

    PubMed Central

    Haji Aghajani, Mohammad; Kobarfard, Farzad; Safi, Olia; Sheibani, Kourosh; Sistanizad, Mohammad

    2013-01-01

    To study the resistance to standard dosage of clopidogrel among Iranian patients following percutaneous coronary intervention measured by platelet aggregation test. Patients undergoing percutaneous coronary intervention in Imam Hussein Medical center, Tehran, Iran, who were under treatment with aspirin, but had no history of clopidogrel usage, entered the study. Patients received standard dosage of clopidogrel (Plavix®, Sanofi, France, 600 mg loading dose and 75 mg/day afterward). Platelet aggregation was measured using light transmission aggregometer. The response to the drug was categorized as complete resistance (platelet aggregation decreased less than 10%), intermediate resistance (platelet aggregation decreased between 10 to 30%) and complete response (platelet aggregation decreased to 30% or more). All patients were evaluated for major adverse cardio vascular events one month after the angioplasty based on MACE criteria by phone contact. Thirty-one patients with a mean age of 59 ± 13 entered the study. Sixty-five percent of patients showed complete response to clopidogrel (95% CI: 45% to 81%), 22% showed intermediate resistance (95% CI: 10-41%) and 13% showed complete resistance (95% CI: 4-30%). One month after the angioplasty, no major adverse cardiovascular event was recorded. Based on our findings, it seems that there is no major difference between Iranian population and other studies regarding the resistance to clopidogrel. Due to the limited number of participants in our study, further investigations with higher number of patients are recommended to more precisely calculate the percentage of resistance among Iranian patients. PMID:24250685

  9. Accurate Determination of the Volume of an Irregular Helium Balloon

    ERIC Educational Resources Information Center

    Blumenthal, Jack; Bradvica, Rafaela; Karl, Katherine

    2013-01-01

    In a recent paper, Zable described an experiment with a near-spherical balloon filled with impure helium. Measuring the temperature and the pressure inside and outside the balloon, the lift of the balloon, and the mass of the balloon materials, he described how to use the ideal gas laws and Archimedes' principal to compute the average molecular…

  10. Investigating Diffusion and Entropy with Carbon Dioxide-Filled Balloons

    ERIC Educational Resources Information Center

    Jadrich, James; Bruxvoort, Crystal

    2010-01-01

    Fill an ordinary latex balloon with helium gas and you know what to expect. Over the next day or two the volume will decrease noticeably as helium escapes from the balloon. So what happens when a latex balloon is filled with carbon dioxide gas? Surprisingly, carbon dioxide balloons deflate at rates as much as an order of magnitude faster than…

  11. Successful technical and clinical outcome using a second generation balloon expandable coronary stent for transplant renal artery stenosis: Our experience

    PubMed Central

    Salsamendi, Jason; Pereira, Keith; Baker, Reginald; Bhatia, Shivank S; Narayanan, Govindarajan

    2015-01-01

    Transplant renal artery stenosis (TRAS) is a vascular complication frequently seen because of increase in the number of renal transplantations. Early diagnosis and management is essential to optimize a proper graft function. Currently, the endovascular treatment of TRAS using angioplasty and/or stenting is considered the treatment of choice with the advantage that it does not preclude subsequent surgical correction. Treatment of TRAS with the use of stents, particularly in tortuous transplant renal anatomy presents a unique challenge to an interventional radiologist. In this study, we present three cases from our practice highlighting the use of a balloon-expandable Multi-Link RX Ultra coronary stent system (Abbott Laboratories, Abbott Park, Illinois, USA) for treating high grade focal stenosis along very tortuous renal arterial segments. Cobalt–Chromium alloy stent scaffold provides excellent radial force, whereas the flexible stent design conforms to the vessel course allowing for optimal stent alignment. PMID:26629289

  12. Innovations in Balloon Catheter Technology in Rhinology.

    PubMed

    D'Anza, Brian; Sindwani, Raj; Woodard, Troy D

    2017-03-31

    Since being introduced more than 10 years ago, balloon catheter technology (BCT) has undergone several generations of innovations. From construction to utilization, there has been a myriad of advancements in balloon technology. The ergonomics of the balloon dilation systems have improved with a focus on limiting the extra assembly. "Hybrid" BCT procedures have shown promise in mucosal preservation, including treating isolated complex frontal disease. Multiple randomized clinical trials report improved long-term outcomes in stand-alone BCT, including in-office use. The ever-expanding technological innovations ensure BCT will be a key component in the armamentarium of the modern sinus surgeon.

  13. Stratospheric electric field measurements with transmediterranean balloons

    NASA Astrophysics Data System (ADS)

    de La Morena, B. A.; Alberca, L. F.; Curto, J. J.; Holzworth, R. H.

    1993-01-01

    The horizontal component of the stratospheric electric field was measured using a balloon in the ODISEA Campaign of Transmediterranean Balloon Program. The balloon flew between Trapani (Sicily) and El Arenosillo (Huelva, Spain) along the 39 deg N parallel at a height between 34 and 24 km. The high values found for the field on fair-weather and its quasi-turbulent variation, both in amplitude and direction, are difficult to explain with the classical electric field source. A new source, first described by Holzworth (1989), is considered as possibly causing them.

  14. The balloon and the airship technological heritage

    NASA Technical Reports Server (NTRS)

    Mayer, N. J.

    1981-01-01

    The balloon and the airship are discussed with emphasis on the identification of commonalities and distinctions. The aerostat technology behind the shape and structure of the vehicles is reviewed, including a discussion of structural weight, internal pressure, buckling, and the development of a stable tethered balloon system. Proper materials for the envelope are considered, taking elongation and stress into account, and flight operation and future developments are reviewed. Airships and tethered balloons which are designed to carry high operating pressure with low gas loss characteristics are found to share similar problems in low speed flight operations, while possessing interchangeable technologies.

  15. A balloon-borne integrating nephelometer

    SciTech Connect

    Brown, G.S.; Apple, M.L. ); Weiss, R.E. )

    1990-09-01

    A balloon-borne integrating nephelometer has been successfully developed and flown by Sandia National Laboratories and Radiance Research. This report details instrument design, calibration and data conversion procedure. Free and tethered balloon transport and telemetry systems are described. Data taken during March 1989 South-Central New Mexico free flight ascents are presented as vertical profiles of atmospheric particle scattering coefficient, temperature and balloon heading. Data taken during December 1989 Albuquerque, New Mexico tethered flights are also presented as vertical profiles. Data analysis shows superior instrument performance. 5 refs., 22 figs.

  16. A comparative study of internally and externally capped balloons using small scale test balloons

    NASA Technical Reports Server (NTRS)

    Bell, Douglas P.

    1994-01-01

    Caps have been used to structurally reinforce scientific research balloons since the late 1950's. The scientific research balloons used by the National Aeronautics and Space Administration (NASA) use internal caps. A NASA cap placement specification does not exist since no empirical information exisits concerning cap placement. To develop a cap placement specification, NASA has completed two in-hangar inflation tests comparing the structural contributions of internal caps and external caps. The tests used small scale test balloons designed to develop the highest possible stresses within the constraints of the hangar and balloon materials. An externally capped test balloon and an internally capped test balloon were designed, built, inflated and simulated to determine the structural contributions and benefits of each. The results of the tests and simulations are presented.

  17. Delayed reendothelialization with rapamycin is rescued by the addition of nicorandil in balloon-injured rat carotid arteries

    PubMed Central

    Zhang, Ying Qian; Tian, Feng; Chen, Jin Song; Chen, Yun Dai; Zhou, Ying; Li, Bo; Ma, Qiang; Zhang, Ying

    2016-01-01

    Rapamycin is an immunosuppressive agent that is added to drug eluting stents. It prevents restenosis, but it also impairs reendothelialization. Nicorandil is a hybrid agent with adenosine triphosphated (ATP)-sensitive K+ (KATP) channel opener and nitrate properties. It prevents oxidative stress and cell apoptosis induced by rapamycin in endothelial cells in vitro. However, whether nicorandil promotes reendothelialization after angioplasty delayed by rapamycin remains to be determined. Balloon injury model was established in SD rats. Nicorandil increased reendothelialization impaired by rapamycin, and it decreased xanthine oxidase (XO)-generated reactive oxygen species (ROS) induced by rapamycin. In addition, eNOS expression inhibited by rapamycin was increased by nicorandil in vivo. In vitro, rapamycin-impeded cardiac microvascular endothelial cells (CMECs) migration, proliferation and rapamycin-induced ROS production were reversed by nicorandil. Knockdown of XO partially inhibited rapamycin-induced ROS production and cell apoptosis in CMECs, and it promoted CMECs migration and proliferation suppressed by rapamycin. Knockdown of Akt partially prevents eNOS upregulation promoted by nicorandil. The beneficial effect of nicorandil is exhibited by inhibiting XO and up-regulating Akt pathway. Nicorandil combined with rapamycin in effect rescue the deficiencies of rapamycin alone in arterial healing after angioplasty. PMID:27713157

  18. The Role of Coagulation and Inflammation After Angioplasty in Patients with Peripheral Arterial Disease

    SciTech Connect

    Wahlgren, C.M. Sten-Linder, M.; Egberg, N.; Kalin, B.; Blohme, L.; Swedenborg, J.

    2006-08-15

    Purpose. Restenosis remains a frequent complication after angioplasty in peripheral arterial disease. Inflammation plays a critical role in the vascular response to injury. Effective medical treatment to improve patency after angioplasty is still elusive. The aims of this prospective clinical study were to investigate changes in blood coagulation and inflammatory markers after angioplasty and their significance for restenosis. Methods. Thirty-four patients with peripheral arterial disease underwent angioplasty of the iliac and superficial femoral arteries. Ten patients undergoing diagnostic angiography were included in the study as controls. Plasma levels of tissue factor, prothrombin fragment 1 + 2, D-dimer, P-selectin, C-reactive protein (CRP), and fibrinogen were analyzed before and after angioplasty. Patients were followed up with angiography after 6 months to assess restenosis. Results. CRP was elevated the day after angioplasty (6.6 mg/l, p = 0.0001) and tended to peak after 1 week (11 mg/l, p = 0.09). There was a significant increase of D-dimer and P-selectin 1-4 hr after angioplasty (0.4 mg/l, p = 0.001 and 68 ng/ml, p = 0.05, respectively). None of the biochemical markers was a statistically significant predictor of restenosis. Conclusion. We have observed a much more prolonged inflammatory response than previously noted, but only minor changes in coagulation activity after angioplasty. The biochemical markers, before and after angioplasty, were not related to restenosis. Further studies are needed to delineate the molecular mechanisms behind these observations and their involvement in thrombosis and restenosis. If these pathways are further defined, improved treatment strategies, including antithrombotic treatments and statins, could be tailored to modulate postprocedural inflammation.

  19. Balloon-expandable covered stent therapy of complex endovascular pathology.

    PubMed

    Giles, Heath; Lesar, Christopher; Erdoes, Luke; Sprouse, Richard; Myers, Stuart

    2008-11-01

    restenosis rate included two renal artery occlusions in patients noncompliant with clopidogrel use and resulted in ipsilateral kidney loss in both patients. In-stent peak systolic velocities decreased significantly (p<0.05) from preoperation to 12 months in iliac stents and to 18 months in renal stents. Ankle-brachial index increased significantly in iliac stents from preoperation (0.62+/-0.18) to 18 months (0.86+/-0.16). Successful exclusion of atheromatous lesions and aneurysm/dissection/endoleak was 100%. Access-site complications occurred in 6%: pseudoaneurysm (n=2), dissection (n=1), and bleeding (n=1). Balloon-expandable covered stents have an acceptable primary patency with an excellent assisted patency after salvage angioplasty. The clinical utility of this technology is broad for the treatment of aneurysms, extravasation, unstable atheromatous lesions, and recurrent in-stent restenosis.

  20. Successful Angioplasty of Left Vertebral Artery and Right Subclavian Artery Via Retrograde Approach

    PubMed Central

    Namazi, Mohammad Hasan; Momenizadeh, Amir; Dousti, Amir; Naderian, Mohammadreza

    2017-01-01

    We describe a 77-year-old male who had right upper limb ischemic symptoms and history of unsuccessful right subclavian artery angioplasty. According to ultrasound findings, upper limb angiography was performed which confirmed stenosis of the left vertebral and right subclavian arteries. Percutaneous angioplasty and stenting of left vertebral and right subclavian arteries were performed in two separate sessions. Retrograde approach was scheduled for right subclavian artery angioplasty which is challenging due to potential risks to adjacent vertebral artery. This case reports underscores that percutaneous approaches may be preferential given their confirmed long-term efficacy and lower morbidity.

  1. The Helium Balloon Project: Expanding Student Horizons...

    ERIC Educational Resources Information Center

    Leyden, Michael B.

    1973-01-01

    An activity involving future elementary school teachers designed around inexpensive balloons which when launched contained postcards to determine the geographic location of the landing. The investigation is student-centered, involving unknown questions, and was conducted for enjoyment. (DF)

  2. Mass and radius of cosmic balloons

    NASA Technical Reports Server (NTRS)

    Wang, Yun

    1994-01-01

    Cosmic balloons are spherical domain walls with relativistic particles trapped inside. We derive the exact mass and radius relations for a static cosmic balloon using Gauss-Codazzi equations. The cosmic balloon mass as a function of its radius, M(R), is found to have a functional form similar to that of fermion soliton stars, with a fixed point at 2GM(R)/R approximately or equal to 0.486 which corresponds to the limit of infinite central density. We derive a simple analytical approximation for the mass density of a spherically symmetric relativistic gas star. When applied to the computation of the mass and radius of a cosmic balloon, the analytical approximation yields fairly good agreement with the exact numerical solutions.

  3. Balloon Measurements of Winds in Planetary Atmospheres

    NASA Astrophysics Data System (ADS)

    Wayne, S.; Kitchen, A.; Perry, R.; Petersen, P.; Slater, J.; Oudrhiri, K.; Asmar, S.; Atkinson, D.

    2014-06-01

    Atmospheric dynamics can be better measured if data is recorded from many spatially separated capsules. One method under study is to use a planetary lander that releases multiple balloon-bourne transceivers that can be Doppler tracked by the lander.

  4. Analysis and prediction of stratospheric balloons trajectories

    NASA Astrophysics Data System (ADS)

    Cardillo, A.; Memmo, A.; Musso, I.; Ibba, R.; Spoto, D.

    The first step to manage a balloon flight from a trajectory point of view is the definition of launch location and period. Analysis data are used to realize a statistical study of the trajectories that can be obtained. The goal is define the conditions able to maximize the probability to respect mission objectives and constrains. Ones started with operations the balloon control centre has to manage the flight respecting safety and science. To predict stratospheric balloon trajectories we must utilize data from different forecast models and real-time measurements of wind and other meteorological entities. These sources of information have to be merged along the simulation of the balloon flight. Great attention has be paid for long duration flight from Pole and Equator, where QBO plays an important role.

  5. Investigations of Balloon and Aeroplane Fabrics

    NASA Technical Reports Server (NTRS)

    Gibbons, Willis A; Smith, Omar H

    1917-01-01

    Report presents the experimental results of fabrics used for balloons and aeroplanes. Tensile properties, surface roughness, skin friction, flammability, permeability, and water absorption were tested for different combinations of materials.

  6. Deployment Instabilities of Lobed-Pumpkin Balloon

    NASA Astrophysics Data System (ADS)

    Nakashino, Kyoichi

    A lobed-pumpkin balloon, currently being developed in ISAS/JAXA as well as in NASA, is a promising vehicle for long duration scientific observations in the stratosphere. Recent ground and flight experiments, however, have revealed that the balloon has deployment instabilities under certain conditions. In order to overcome the instability problems, a next generation SPB called 'tawara' type balloon has been proposed, in which an additional cylindrical part is appended to the standard lobed-pumpkin balloon. The present study investigates the deployment stability of tawara type SPB in comparison to that of standard lobed-pumpkin SPB through eigenvalue analysis on the basis of finite element methods. Our numerical results show that tawara type SPB enjoys excellent deployment performance over the standard lobed-pumpkin SPBs.

  7. Power Systems Design for Long Duration Ballooning

    NASA Technical Reports Server (NTRS)

    Stilwell, Bryan; Chuzel, Alain

    2016-01-01

    The Columbia Scientific Balloon Facility has been designing and building high-altitude balloon power systems for over 26 years. With that experience, we have found certain types of PV panels, batteries, and charge controllers that are reliable in stratospheric environments. The ultimate goal is to ensure that power systems will provide power reliably throughout the duration of an LDB flight. The purpose of this presentation is to provide some general guidelines and best practices for power system design.

  8. Cervical balloon for dysfunctional labor following amniotomy.

    PubMed

    Lurie, S; Rabinerson, D; Feinstein, M; Mamet, Y

    1998-01-01

    The conventional treatment for arrest of protracted active phase dilatation is amniotomy and oxitocin. This kind of labor dystocia is associated with an increased incidence in Cesarean delivery. We describe the use of cervical balloon after amniotomy for protracted active phase dilatation. We have used this approach in five parturients. All five patients had a spontaneous vaginal delivery. Intrapartum cervical balloon in patients with dysfunctional labor may reduce the need for Cesarean delivery.

  9. Advances in Scientific Balloon Thermal Modeling

    NASA Technical Reports Server (NTRS)

    Bohaboj, T.; Cathey, H. M., Jr.

    2004-01-01

    The National Aeronautics and Space Administration's Balloon Program office has long acknowledged that the accurate modeling of balloon performance and flight prediction is dependant on how well the balloon is thermally modeled. This ongoing effort is focused on developing accurate balloon thermal models that can be used to quickly predict balloon temperatures and balloon performance. The ability to model parametric changes is also a driver for this effort. This paper will present the most recent advances made in this area. This research effort continues to utilize the "Thrmal Desktop" addition to AUTO CAD for the modeling. Recent advances have been made by using this analytical tool. A number of analyses have been completed to test the applicability of this tool to the problem with very positive results. Progressively detailed models have been developed to explore the capabilities of the tool as well as to provide guidance in model formulation. A number of parametric studies have been completed. These studies have varied the shape of the structure, material properties, environmental inputs, and model geometry. These studies have concentrated on spherical "proxy models" for the initial development stages and then to transition to the natural shaped zero pressure and super pressure balloons. An assessment of required model resolution has also been determined. Model solutions have been cross checked with known solutions via hand calculations. The comparison of these cases will also be presented. One goal is to develop analysis guidelines and an approach for modeling balloons for both simple first order estimates and detailed full models. This papa presents the step by step advances made as part of this effort, capabilities, limitations, and the lessons learned. Also presented are the plans for further thermal modeling work.

  10. TMBM: Tethered Micro-Balloons on Mars

    NASA Technical Reports Server (NTRS)

    Sims, M. H.; Greeley, R.; Cutts, J. A.; Yavrouian, A. H.; Murbach, M.

    2000-01-01

    The use of balloons/aerobots on Mars has been under consideration for many years. Concepts include deployment during entry into the atmosphere from a carrier spacecraft, deployment from a lander, use of super-pressurized systems for long duration flights, 'hot-air' systems, etc. Principal advantages include the ability to obtain high-resolution data of the surface because balloons provide a low-altitude platform which moves relatively slowly. Work conducted within the last few years has removed many of the technical difficulties encountered in deployment and operation of balloons/aerobots on Mars. The concept proposed here (a tethered balloon released from a lander) uses a relatively simple approach which would enable aspects of Martian balloons to be tested while providing useful and potentially unique science results. Tethered Micro-Balloons on Mars (TMBM) would be carried to Mars on board a future lander as a stand-alone experiment having a total mass of one to two kilograms. It would consist of a helium balloon of up to 50 cubic meters that is inflated after landing and initially tethered to the lander. Its primary instrumentation would be a camera that would be carried to an altitude of up to tens of meters above the surface. Imaging data would be transmitted to the lander for inclusion in the mission data stream. The tether would be released in stages allowing different resolutions and coverage. In addition during this staged release a lander camera system may observe the motion of the balloon at various heights above he lander. Under some scenarios upon completion of the primary phase of TMBM operations, the tether would be cut, allowing TMBM to drift away from the landing site, during which images would be taken along the ground.

  11. Long-term follow-up of stent implantation versus stent-like angioplasty in unstable angina.

    PubMed

    Marzocchi, A; Ortolani, P; Piovaccari, G; Marrozzini, C; Palmerini, T; Marinucci, L; Saia, F; Bacchi-Reggiani, M L; Branzi, A; Magnani, B

    1999-03-01

    Stent-like plain old balloon angioplasty (POBA, < or = 30% residual diameter stenosis) in patients with stable angina resulted in a clinical and angiographic long-term outcome equivalent to stenting. In unstable angina POBA showed lower acute and long-term efficacy than in the stable setting. Data comparing stent-like POBA and coronary stenting in unstable angina are lacking in the literature. The aim of this retrospective single-center study was to compare the long-term effectiveness of stent-like POBA and coronary stenting in unstable angina. From January 1996 to December 1996 we retrospectively examined 187 consecutive patients with unstable angina who underwent coronary angioplasty on a native vessel: 135 had coronary stenting in addition to POBA and 50 achieved a stent-like result with POBA. Two patients, with major contraindication to coronary stenting, who did not reach a stent-like angiographic result, were also treated with only POBA but were excluded from the study. Stent implantation indications were: elective (54 stents, 30%), suboptimal angiographic result (104 stents, 58%), and bail-out situation (21 stents, 12%). Stent implantation showed high angiographic (98.5%) and clinical (95.5%) success. Stent thrombosis occurred only in 2 patients (1.5%). At quantitative coronary angiography the stent group showed a higher post-procedure minimal lumen diameter (2.74 +/- 1.25 vs 2.27 +/- 0.58 mm, p = 0.025), acute gain (1.95 +/- 1.28 vs 1.43 +/- 0.57 mm, p = 0.007) and lower residual stenosis diameter (13.89 +/- 7.43 vs 20.4 +/- 7.28%, p = 0.001) than the stent-like POBA group. At 1-year follow-up the stent group showed a higher event-free survival rate (77.9 vs 64.6%, p = 0.009) mainly due to lower recurrence of angina and repetition of percutaneous procedures. Stent-like POBA procedure and baseline lesion length > or = 10 mm proved to be the only independent predictors of long-term ischemic event occurrence. In conclusion, in unstable angina, stent

  12. Stratospheric balloons trajectories predictions and optimizations

    NASA Astrophysics Data System (ADS)

    Musso, I.; Cardillo, A.; Memmo, A.

    Trajectory predictions are becoming an important part of the stratospheric balloons activities due to the increased safety and scientific requirements Often high-populated areas must be avoided while the balloon could be asked to reach regions interesting for scientific measurements The balloon trajectory s reconstruction is essentially a time propagation of local wind vectors along the expected altitudes As consequence the predictor is composed of two interconnected subsystems one for the definition of vertical position and one for the wind predictions and horizontal propagation at every time step Forecast data permits up to 6 days of wind vector predictions Below 10mb altitude mesoscale models reduce the wind prediction uncertainty Directly measured information comes from radiosoundings few hours before flight or during it GPS onboard the balloon telemetry is a second direct wind data source The software has to mesh these different flows of information giving to the measured values a weight inversely proportional to the time and space distance from wind measurements In this way sounding data if properly used are able to reduce the path s dispersion A thermodynamic model reconstructs the balloon vertical positions Heat exchanges between internal gas and external environment are very sensitive to air temperature infrared radiance and albedo Again forecast data have to be properly meshed with radiosoundings and satellite images to obtain the best values of these border conditions They will apply the thermodynamic balloon model We

  13. Hybrid designs for super-pressure balloons

    NASA Astrophysics Data System (ADS)

    Schur, W.; Baginski, F.

    The desire of the scientific community to fly large payloads at mid latitudes over durations of months while keeping altitude has propelled NASA on the path of developing an Ultra Long Duration Balloon (ULDB) design. The first design considered for ULDB was a spherical balloon, but the strength of its fabric composite fell far short of the capacity goal set by NASA. Therefore, an alternative design, the pumpkin-shape balloon, was chosen. For large balloons with a large number of gores, the pumpkin design is found to be susceptible to flawed deployment. While research on pumpkin balloon deployment is on-going, the spherical balloon design has stirred new interest for certain applications. Current spherical super-pressure designs have a load skirt that consists of straps that are attached tangentially to the fully inflated sphere. The attachment points constitute stress raisers, and the straps provide an opportunity for entanglement. The pneumatic envelope is a compliant structure that accommodates concentrated loads by large out-of-plane deformation. By embedding sufficient unidirectional strength elements in the skin that radiate from the nadir upward, we will demonstrate that the load skirt is unnecessary and the entanglement problem is avoided. We will use analytical investigations to establish the advantages of this hybrid design.

  14. Adjuncts to Improve Nasal Reconstruction Results.

    PubMed

    Gordon, Shayna Lee; Hurst, Eva A

    2017-02-01

    The final cosmetic appearance of nasal reconstruction scars is of paramount importance to both the patient and surgeon. Ideal postreconstruction nasal scars are flat and indistinguishable from surrounding skin. Unfortunately, even with meticulous surgical execution, nasal scars can occasionally be suboptimal. Abnormal fibroblast response can lead to hypertrophic nasal scars, and excessive angiogenesis may lead to telangiectasias or an erythematous scar. Imperfect surgical closure or poor postoperative management can lead to surgical outcomes with step-offs, depressions, suture marks, or dyspigmentation. Aesthetically unacceptable nasal scars can cause pruritus, tenderness, pain, sleep disturbance, and anxiety and depression in postsurgical patients. Fortunately, there are several minimally invasive or noninvasive techniques that allow for enhancement and improvement of cosmetic results with minimal risk and associated downtime. This article provides an overview of adjuncts to improve nasal reconstruction with a focus on techniques to be used in the postoperative period. Armed with an understanding of relevant available therapies, skillful surgeons may drastically improve the final cosmesis and outcome of nasal reconstruction scars.

  15. Sensewheel: an adjunct to wheelchair skills training.

    PubMed

    Symonds, Andrew; Taylor, Stephen J G; Holloway, Catherine

    2016-12-01

    The purpose of this Letter was to investigate the influence of real-time verbal feedback to optimise push arc during over ground manual wheelchair propulsion. Ten healthy non-wheelchair users pushed a manual wheelchair for a distance of 25 m on level paving, initially with no feedback and then with real-time verbal feedback aimed at controlling push arc within a range of 85°-100°. The real-time feedback was provided by a physiotherapist walking behind the wheelchair, viewing real-time data on a tablet personal computer received from the Sensewheel, a lightweight instrumented wheelchair wheel. The real-time verbal feedback enabled the participants to significantly increase their push arc. This increase in push arc resulted in a non-significant reduction in push rate and a significant increase in peak force application. The intervention enabled participants to complete the task at a higher mean velocity using significantly fewer pushes. This was achieved via a significant increase in the power generated during the push phase. This Letter identifies that a lightweight instrumented wheelchair wheel such as the Sensewheel is a useful adjunct to wheelchair skills training. Targeting the optimisation of push arc resulted in beneficial changes in propulsion technique.

  16. Comparison of a Balloon Guide Catheter and a Non-Balloon Guide Catheter for Mechanical Thrombectomy.

    PubMed

    Velasco, Aglaé; Buerke, Boris; Stracke, Christian P; Berkemeyer, Shoma; Mosimann, Pascal J; Schwindt, Wolfram; Alcázar, Pedro; Cnyrim, Christian; Niederstadt, Thomas; Chapot, René; Heindel, Walter

    2016-07-01

    Purpose To evaluate the effectiveness of mechanical thrombectomy with the use of a stent retriever in acute ischemic stroke, performed by using a balloon guide catheter or non-balloon guide catheter. Materials and Methods In accordance with the institutional review board approval obtained at the two participating institutions, retrospective analysis was performed in 183 consecutive patients treated between 2013 and 2014 for occlusions in the middle cerebral artery or carotid terminus by using a stent retriever with a balloon guide catheter (n = 102) at one center and a non-balloon guide catheter (n = 81) at the other center. Data on procedure duration, number of passes, angiographic findings, type of stent retriever used, and expertise of the operators were collected. Successful recanalization was defined as grade 3 or 2b modified Treatment in Cerebral Ischemia recanalization accomplished in up to three passes. Univariate and multivariate subgroup analyses were conducted to control for the confounding variables of prior thrombolysis, location of occlusion, and operator expertise. Results Successful recanalization with the balloon guide catheter was achieved in 89.2% of thrombectomies (91 of 102) versus 67.9% (55 of 81) achieved with the non-balloon guide catheter (P = .0004). The one-pass thrombectomy rate with the balloon guide catheter was significantly higher than for that with the non-balloon guide catheter (63.7% [65 of 102] vs 35.8% [29 of 81], respectively; P = .001). The procedure duration was significantly shorter by using the balloon guide catheter than the non-balloon guide catheter (median, 20.5 minutes vs 41.0 minutes, respectively; P < .0001). Conclusion The effectiveness of mechanical thrombectomy with stent retrievers in acute ischemic stroke in the anterior circulation in terms of angiographic results and procedure duration was improved when performed in combination with the balloon guide catheter. (©) RSNA, 2016.

  17. Gondola development for CNES stratospheric balloons

    NASA Astrophysics Data System (ADS)

    Vargas, A.; Audoubert, J.; Cau, M.; Evrard, J.; Verdier, N.

    The CNES has been supporting scientific ballooning since its establishment in 1962. The two main parts of the balloon system or aerostat are the balloon itself and the flight train, comprising the house-keeping gondola, for the control of balloon flight (localization and operational telemetry & telecommand - TM/TC), and the scientific gondola with its dedicated telecommunication system. For zero pressure balloon, the development of new TM/TC system for the housekeeping and science data transmission are going on from 1999. The main concepts are : - for balloon house-keeping and low rate scientific telemetry, the ELITE system, which is based on single I2C bus standardizing communication between the different components of the system : trajectography, balloon control, power supply, scientific TM/TC, .... In this concept, Radio Frequency links are developed between the house keeping gondola and the components of the aerostat (balloon valve, ballast machine, balloon gas temperature measurements, ...). The main objectives are to simplify the flight train preparation in term of gondola testing before flight, and also by reducing the number of long electrical cables integrated in the balloon and the flight train; - for high rate scientific telemetry, the use of functional interconnection Internet Protocol (IP) in interface with the Radio Frequency link. The main idea is to use off-the-shelf IP hardware products (routers, industrial PC, ...) and IP software (Telnet, FTP, Web-HTTP, ...) to reduce the development costs; - for safety increase, the adding, in the flight train, of a totally independent house keeping gondola based on the satellite Inmarsat M and Iridium telecommunication systems, which permits to get real time communications between the on-board data mobile and the ground station, reduced to a PC computer with modem connected to the phone network. These GEO and LEO telecommunication systems give also the capability to operate balloon flights over longer distance

  18. Adjunctation and Scalar Product in the Dirac Equation - I

    NASA Astrophysics Data System (ADS)

    Dima, M.

    2016-02-01

    The Bargmann-Pauli adjunctator (hermitiser) of {C}{l}_{_{1,3}}(C) is derived in a representation independent way, circumventing the early derivations (Pauli, Ann. inst. Henri Poincaré 6, 109 and 121 1936) using representation-dependent arguments. Relations for the adjunctator's transformation with the scalar product and space generator set are given. The S U(2) adjunctator is shown to determine the {C}{l}_{_{1,3}}(C) adjunctator. Part-II of the paper will approach the problem of the two scalar products used in Dirac theory - an unphysical situation of "piece-wise physics" with erroneous results. The adequate usage of scalar product - via calibration - will be presented, in particular under boosts, yielding the known covariant transformations of physical quantities.

  19. Dietary Adjuncts for Improving Testosterone Levels in Hypogonadal Males.

    PubMed

    Kovac, Jason R; Pan, Michael; Arent, Shawn; Lipshultz, Larry I

    2016-11-01

    An increasing number of men are being diagnosed with hypogonadism. While many benefit from testosterone supplementation therapy, others who do not meet the criteria for hormone supplementation have turned to dietary adjuncts as a way or gaining improvements in libido, energy, and physical performance. These oral adjunct medications include controlled substances such as androstenedione, androstenediol as well as other "over-the-counter" options like DHEA (dehydroepiandrosterone) and herbal remedies like Tribulus terrestris This review will focus on the use of these adjunct medications in isolation, or in combination with testosterone supplementation therapy as well as the biochemical nature of the supplements, the results of scientific trials as well as the side effects that limit their use. At the end of this review, physicians will have an improved understanding of the popular testosterone adjuncts being used currently as well as the availability of these substances and how they are used.

  20. Ulcerated Radiodermatitis Induced after Fluoroscopically Guided Stent Implantation Angioplasty

    PubMed Central

    Herz-Ruelas, Maira Elizabeth; Gómez-Flores, Minerva; Moxica-del Angel, Joaquín; Miranda-Maldonado, Ivett; Gutiérrez-Villarreal, Ilse Marilú; Villarreal-Rodríguez, Adriana Orelia

    2014-01-01

    Cases of radiation-induced skin injury after fluoroscopically guided procedures have been reported since 1996, though the majority of them have been published in Radiology and Cardiology literature, less frequently in Dermatology journals. Chronic radiation dermatitis induced by fluoroscopy can be difficult to diagnose; a high grade of suspicion is required. We report a case of an obese 46-year-old man with hypertension, dyslipidemia, and severe coronary artery disease. He developed a pruritic and painful atrophic ulcerated skin plaque over his left scapula, six months after fluoroscopically guided stent implantation angioplasty. The diagnosis of radiodermatitis was confirmed histologically. We report this case to emphasize the importance of recognizing fluoroscopy as a cause of radiation dermatitis. A good clinical follow-up at regular intervals is important after long and complicated procedures, since the most prevalent factor for injury is long exposure time. PMID:25276441