8:45 am

Percutaneous Closure of Muscular VentricularSeptal Defects With a New Prosthesis in a CanineModelXiaoping Gu, MD, Minneapolis, MN. Zahid Amin,MD • Myra C. Urness. John 1. Bass. James Berry •

Kurt A. Amplatz, MD

PURPOSE: To evaluate a new self-expanding prosthesisfor percutaneous closure of muscular VSD.

MATERIALS AND METHODS: Percutaneous closure ofsurgically created muscular VSD's (echo-measured diam­eter, 9.0 :± 3.3 mm) was attempted in 8 adult dogs. Theprosthesis was constructed from fine Nitinol wires in theshape of two buttons with a connecting waist corre­sponding to the size of VSD and thickness of the ven­tricular septum. The device is filled with polyester fibers,and delivered through a 7F sheath via femoral veinapproach. Left ventriculography and/or echocardiogra­phy were performed before and after placement, at one­week, one-month and three months.

RESULTS: Placement was successful in all 8 animals. Onedog died 3 hours after placement. Port-mortem exami­nation showed a hemothorax related to surgery. Onedog reqmred a second device because of the shape andsize of the defect. The VSD closure rate was 37.5% (3/8)after placement, 85.7% (617) at one week and 100% (717)

at one month. Complete fibrous incorporation of thedevice was noted at three months.

CONCLUSION The device appears highly effective forpermanent occlusion of muscular VSD, with advantagesof easy placement, self-centering, repositioning and us­ing small delivery system.

9:00 am

Imaging-Guided Thoracentesis and Paracentesis:Major Complications and Lessons in AvoidanceAlbert A. Nemcek, Jr., MD, Chicago, IL. Howard BrettChrisman, MD • Reed Ali Omary, MD • MichaelAndrew Bruan, MD. Brian A. Aronson, MD

PURPOSE: To determine major complication rates andidentify contributing factors in a large series of imaging­guided thoracenteses and paracenteses.

MATERIALS AND METHODS: Utilizing a dedicated inter­ventional radiology database, major complications werereviewed and analyzed to assess potentially avoidablefactors.

RESULTS: 523 paracenteses resulted in two major com­plications (0.4%), both surgically confirmed inferior epi­gastric artery lacerations in coagulopathic patients. 700thoracenteses resulted in twelve major complications(2.4%). Two deaths (0.3%) occurred, one from spleniclaceration during aspiration of a small pleural effusionwithout real-time guidance and a second in a patientwith severe thrombocytopenia. Two other hemorrhagic

complications, one resulting from laceration of an aber­rant intercostal artery, were associated with severe co­agulopathy. Seven complications were pneumothoracesrequiring chest tubes 0.0%).

CONCLUSIONS: While complication rates from imaging­guided thoracentesis and paracentesis compare favor­ably to results from "blind" guidance, major complica­tions still occurred. In paracentesis, standard anatomicprecautions or pre-procedural identification of epigastricvessels would likely have prevented the two major com­plications. Besides bleeding diathesis, one factor seem­

ingly operative in select thoracenteses was a previouslyundescribed "blow-out" injury of poorly expansile lungssubjected to high negative intrapleural pressures. Wealso recommend use of real-time guidance for aspirationof smaller effusions.

9:15 am

Management of Post-Operative Chyle Leakage viaPercutaneous Catheterization of the CisternaChyli: Preliminary StudyConstantin Cope, MD, Philadelphia, PA

PURPOSE: To identify and treat lymph duct leakage inpatients with unremitting post surgical chylous ascites orchylothorax by using percutaneous puncture of the cis­terna chyli (CC) and embolization of the thoracic duct(TD).

MATERIALS AND METHODS: Three patients had chylousascites; one had a chylothorax despite previous surgicalTD ligation. Following pedal lymphography, the CC wassuccessfully punctured transabdominally with a skinnyneedle in all; the TD was catheterized with a 3F catheterin 2 patients.

RESULTS: A leaking small retroperitoneal lymph vesselwhich could not be catheterized was identified by prox­imal TD opacification in one of three cases with chylousascites; in the patient with chylothorax, laceration of aTD parallel branch was identified and selectively embo­lized with microcoils with complete control of the fistula.There was no morbidity.

CONCLUSIONS: Percutaneous transabdominal CC cathe­terization is feasible and safe; it permits accurate local­ization of lymph leakage. The potential for identifyingand embolizing TD lacerations is promising.

Sunday, March 1,1998

1:00 pm-2:30 pm

Scientific Session 4

Carotid & Subclavian InterventionModerator: Wayne F. Yakes, MD

161

162

1:00 pm

Endovascular Treatment of AtheroscleroticStenosis of the Internal CarotidMichel Henry, MD, Essey-Les-Nancy, France. Max

Amor, MD • Isabelle Henry, MD • Isabelle Masson, MD

• Kiril Tzvetanov, MD. Edmond LeBorgne, MD

PURPOSE- To study endovascular treatment (angio­plasty-stents) of atherosclerotic stenoses of internal ca­rotid artery to determine if it may partially replace sur­gical endarterectomy; to evaluate benefits of angioplastyHenryunder cerebral protection.

METHODS AND MATERIALS: 131 internal carotid arterieswith ~75% stenosis treated in 124 pts (M:91, F:33) meanage: 72.7 ± 10.2 yrs (47-93). Mean lesion length: 15.1 ±4.1 mm. Mean arterial diameter: 5.8 mm ± 0.6.7 pts hadcontralateral carotid thrombosed. 40% of the pts weresymptomatic, 60% were asymptomatic (65% of the ptshad severe coronary disease, 45% had peripheral vascu­lar diseases). Predilatation of the stenosis always per­formed before stenting. Stents deployed in all carotidsbut 1: Palmas stents (n = 95), Wallstent (n = 35),Strecker stent (n = 2), Wiktor (n = 1), NIR (n = 1). 104carotid art, treated without cerebral protection (fern. ap­

proach: 89, direct puncture: 13, brachial approach: 2). 27carotids treated with cerebral protection (triple coaxialcatheter) via fern. approach. Pts had neurological exam­ination, CT scan, echodoppler, angiography before/afterprocedure and at 6 months follow-up.

RESULTS: Immediate technical success for stenosis:100%. Mean % stenosis reduced from 85.1 ± 7.6 to 2.1 ±6. Neurological complications: 7(5.4%). Without cerebralprotection we observed: 3 TIAs, 1 minor stroke, 1 majorstroke (hemiplegia) and with protection: 2 major strokes(1 amaurosis, 1 hemiplegia). 3 access site hematomas.No death, 90 pts were controlled at 6 months follow-up.We observed 1 mild compression of a Palmaz stent and4 restenoses (4.4%), 1 silent thrombosiS, 1 silent reste­nosis and 1 symptomatic restenosis (TIA) treated by newangioplasty and 1 restenosis with migration of a Wall­stent treated by new PTA and second Wallstent.

CONCLUSION Carotid angioplasty completed withstents seems safe, effective, can be considered as analternative to surgical treatment of atherosclerotic steno­

ses. Cerebral protection has not reduced cerebral com­plication in this series.

1:15 pm

Carotid Stent Supported Angioplasty (CSSA):Results in 135 ArteriesGregory Scott Mencken, MD, Pittsburgh, PA. Mark

Henry Wholey, MD. Michael Henry Wholey, MD, MBA

• Chester R. Jarmolowski, MD. Gustav R. Eles, DO

PURPOSE: To demonstrate the technical results and ef­ficacy of endovascular placement of Palmaz balloon ex­pandable stents for carotid artery occlusive disease.

MATERIALS AND METHODS: The series consists of 127patients with angiographically proven significant carotid

bifurcation or internal carotid artery stenosis with a mean

stenosis rate of 84.9%. There were a total of 135 target

lesions attempted with a Palmaz balloon expandableendovascular stent.

RESULTS: Of the 135 cases, 127 (95.4%) were success­

fully treated with Palmaz endovascular stents. Neuro­

logical complications consisted of three (3) transient

ischemic attacks (2.4%), two (2) minor strokes (1.6%),

and two (2) major strokes (1.6%). There were two (2)

non-related deaths in this series. Neurological, Dopp­ler, or angiographic follow-up at one (1) and six (6)

months demonstrated no ipsilateral neurological

events. There was one restenosis/deformation en­

countered at six (6) month follow-up which was suc­cessfully redilated.

CONCLUSION Carotid stent supported angioplasty with

endovascular Palmaz balloon expandable stent place­

ment is a procedure with high technical success rates

and a limited number of complications suggesting that

this treatment option is a viable alternative in the treat­

ment of carotid artery occlusive disease.

1:30 pm

Current International Status of Carotid ArteryStent PlacementMichael H. Wholey, MD, MBA, New Orleans, LA

PURPOSE: To review the current status of carotid artery

stent placement in the world.

METHODS: Surveys were sent to 28 major interventional

centers in Europe, North and South America and Asia of

which 23 responded. Information from peer-reviewedjournals was also included and supplemented the sur­vey.

RESULTS: The total number of endovascular carotid

stent procedures that have been performed worldwideto date included 2001 cases with a technical success of98.6%. Complications that occurred during the carotidstent placement or within a thirty day period following

placement were recorded. Overall, there were 61 mi­

nor strokes with a rate of occurrence of 3.05%. The

total number of major strokes was 25 for a rate of

1.25%. There were 26 deaths within a 30 day post

procedure period resulting in a mortality rate of 1.30%.

Restenosis rates of carotid stenting have been 4.81% at

6 months.

CONCLUSIONS: Endovascular stent treatment of carotid

artery atherosclerotic disease is growing as alternative

for vascular surgery especially for patients that are high

risk for standard carotid endarterectomy. The periproce­

dural stroke and death rates are generally acceptable at

this early stage of development.

1:45 pm

Spiral CT Angiography: Pre and Post-ProcedureAssessment of Carotid Artery Angioplasty UsingVirtual AngioscopyChristophe S. Bazin, MD, Essey-Les-Nancy, France.Bruno Boyer, MD. Herve Boccaccini, MD • MichaelHenry, MD • Max Amor, MD. Jean Marie Sition, MD

PURPOSE to evaluate prospectively spiral CT angiographywith virtual angioscopy in measuring carotid stenosis be­fore and after angioplasty and complementary data.

MATERIAL AND METHOD: 33 carotid arteries in 32patients were studied within 8 months (january-august1997). CT was performed before and within 24 hoursafter PTA. GEMS CT/i. 3/2/1,5. Smart prep on ascend­ing aorta. Workstation SUN Advantage Windows2.0.20. MPVR with MIP rendering. Virtual Angioscopy.We evaluated ratio between residual lumen or insidestent and internal carotid artery according to NASCETon MPVR view, surface ratio stenosis by contouringmethod, calcification on MIP and on virtual angios­copy, surface 3D, plaque length, brain infarct, stentlocation.

RESULTS: Projection stenosis ratio: 76,34% (50-98). Sur­face stenosis: 71,80% (50-99). Virtual angioscopy helpsin understanding plaque's anatomy but not in measuringpercentage of stenosis. Restoration of circulating lumenwas confirmed from 75 to 100% (mean 95%) by MPVRand virtual angioscopy. All stents were permeable, no

brain infarct. One stent migration down to the commoncarotid artery.

CONCLUSION Spiral CT carotid angiography permitsreliable measurement of carotid artery stenosis beforeand after PTA, provides information aboutsize, morphology and calcification of the plaque. Vir­tual angioscopy provides new anatomic and dynamicdata.

2:00 pm

Mechanical Properties of Anatomically AccurateSilicone Arterial Models Reproducing Normal andPathologic ConditionsJean Micbel Bartoli, MD, Marseille, Ceolep, France.Pierre Henri Rolland, MD. Ali Babak Cuarifi, MD •GuifMoulin, MD. Alain Friggi, MD. CluroglieChagnaud, MD. et al

BACKGROUND: Anatomic vascular models having me­chanical properties relevant to human arteries are lack­ing to evaluate endovascular devices.

ME11fODS: Normal and pathologic corrosion castswere obtained from fresh human arteries. They werecoated with thin silicone layer(s) after draining the

wax exact copies of normal and pathologic vasculartree (with different types of stenosis). We studied

several anatomical models made of various types ofsilicone, pure or loaded with metal or mineral (titani-

um, talc, silica, barium), and having different wallthickness corresponding to 4 to 7 layers of silicone.The models were connected to a pump producingphysiologic syst-diast pressure profile with a liquidhaving the blood viscosity (glycerin:water; 1:3). Inter­nal pressure was measured with a microcatheter andexternal diameter with opposed piezoelectric probes,

at four different pressure ranges (50/110, 80/140, 110/170 and 140/200 mm Hg). Pulsatility, radial force,volumic compliance, elasticity and stiffness of themodels were compared with freshly obtained humancarotid (elastic) and femoral (muscular) arteries.

RESULTS: Under physiological syst-diast pressure, themodel with 4 layers of silicone loaded with titanium(10%, w/w) had rheologic properties identical to thatof human carotid artery. Anatomic, realistic modelswith morphologic stenotic patterns were then created;they were found compatible with MRI, CT, DSA andUS; and they enable evaluation of hemodynamic

changes due to stent implantation.

CONCLUSIONS: Artificial arterial models were created,relevant to the human carotid artery, and exhibiting wallmechanical properties approaching viscoelastic charac­teristics of human arteries. These models provide a real­istic environment for in-vitro endovascular training and

research.

2:15 pm

Endoluminal Treatment of Sub-Clavian OcclusiveDiseases: Percutaneous Angioplasty and StentingMichel Henry, MD, Essey-Les-Nancy, France. MaxAmor, MD. Isabelle Henry, MD. Kiril Tzvetanov, MD• Philippe Kohler, MD • Bernard Mentre, MD

PURPOSE To review feasibility, risks, long term resultsof PTA of sub-clavian artery with/without Palmaz stentplacement.

METHOD AND MATERIALS: Over 9 years, 101 pts under­went percutaneous treatment of sub-clavian occlusivediseases. M:63, F:38, mean age: 62.7 ± 2.2 yrs. Indica­tions for PTA: vertebro-basillar insufficiency (n = 52),superior arm ischemia (n = 43), angina pectoris, before/after internal mammary internal coronary bypass (n = 6)

.49 pts had sub-clavian steel syndrome, 87 arteries ste­nosed, 14 occluded. Mean % stenosis: 82.5 ± 4 [75-100].Mean lesion length: 25.3 ± 1.8 mm [12-30]. Percutane­ous techniques included standard retrograde femoral (n= 85), brachial artery (n = 26) access or both (n = 10),with balloon dilatation of the lesion. Since 1989 Palmazstent implanted for 34 lesions in case of suboptimal PTA(n = 30), important dissection (n = 4).

RESULTS: 91 lesions successfully treated (91%), 4 occlu­sions recanalized (28%). 3 procedural complications (3%)1 11A, 1 major stroke, 1 arterial thrombosis 24 hours afterthe procedure, treated medically. Eligible pts underwentechodoppler/angiographic control at 6 months and echo-

163

164

doppler every 6 months. 13 restenoses treated by new PTA(n == 4), PTA + stent (n == 7), surgery (n == 2). Primary (PI)and secondary patency (PH) for all treated lesions (n ==101) at 8 years follow-up: 65 and 72%. Without stent,respectively 63 and 70%, with stent 75 and 87%. PI and PITfor recanalized lesions (n == 9), 72%, 80%, without stent74%, 82%, with stent 75% and 87% respectively.

CONCLUSION: PTA with/without stenting is safe/effec­tive to treat subclavian artery occlusive diseases withgood long term patency. Occluded vessels do not re­spond well to PTA. Stents (implanted only for poor PTAresults) do not seem to improve long term results.

Scientific Session 5

Dialysis CathetersModerator: Melvin Rosenblatt, MD

1:00 pm

Percutaneous Fibrin Sheath Stripping VersusUrokinase For Malfunctioning Central DialysisCathetersRichard]. Gray, MD, Washington, DC. Amanuel

Fessahaye, MD. Atul Gupta, MD. Keith Marshall

Horton, MD. Lee Haskell Monsein, MD. David Buck,MD. etal

PURPOSE: To compare patencies of catheters followingstripping vs Urokinase infusion.

MATERIALS AND METIIODS: Forty-seven catheters withflow rates less than 250 rnIlminute or 50 rnI/minute lessthan established baseline flow rates were studied byslow (to avoid fibrin sheath disruption) contrast injec­tion. The catheters were prospectively randomized tostripping (28 patients) or Urokinase at 30,000 units/hourvia each port concurrently over four hours (19 patients).

Success and continued patency were determined bydialysis at normal flow rates or at the previously estab­lished baseline flow rate. Flow rates were followedweekly. Primary patency ended with catheter malfunc­tion or removal. Catheters requiring another treatmentmodality for salvage or requiring replacement were con­sidered failures. A Kaplan Meier survival analysis wasused to construct survival curves for both groups.

RESULTS: Fibrin sheaths were demonstrable in 81% (38/47). STRIPPING GROUP: Initial clinical success was 86%(24/28). The primary patency was 50% at 30 days and33% at 45 days. UROKINASE GROUP: Initial clinicalsuccess was 95% (18/19). The primary patency was 67%at 30 days and 37% at 45 days. The Wilcoxon test forequality did not detect a significant difference betweenthe two treatment groups (P==0.35).

CONCLUSION: There is no significant difference in out­comes between the two methods. Both allow temporarycatheter salvage in most patients.

1:15 pm

Outcome of Schon Duo-Flow Hemod.ialysisCatheter InsertionJames Eric Silberzweig, MD, New York, NY. HowardMarks Richard, III, MD • Harold Arthur Mitty, MD

PURPOSE: To evaluate the safety and efficacy of percu­taneously placed Schon Duo-Flow central venous hemo­dialysis catheters in 40 patients.

MATERIALS AND METIIODS: The Schon catheter systemconsists of 2 noncuffed 9-F silicone catheters joined at acommon hub. The hub is positioned between the ve­nous exit site and subcutaneous tunnels. During a6-month period, 43 Schon catheters were inserted in 40patients via the right internal jugular vein (n == 33), leftinternal jugular vein (n == 5), and right subclavian (n ==5) vein. Thirty-seven catheters were placed at new ac­cess sites and 6 catheters were exchanged for existingnontunneled catheters.

RESULTS: Technical success was 100% with no proce­dural complications. Cumulative follow-up includes2877 catheter days (average, 67 days per patient; range,1-157 days). Early complications included catheter kink­ing (n == 3) that required replacement or repositioning,bleeding from the subcutaneous tunnel (n == 2), andinadvertent catheter removal (n == 1). Late complicationsincluded exit site infection (n == 4) and catheter-relatedsepsis (n == 1). Mean flow rate was 273 :!: 37 mllmin.Probability of catheter function was 92% at 30 days and76% at 90 days.

CONCLUSIONS: Use of the Schon Duo-Flow hemodialy­sis catheter system is safe and effective.

1:30 pm

Initial Clinical Expedence With the SchonTunneled Hemodialysis Catheter: ComparisonWith a Standard Tunneled CatheterSanjaya Viswamitra, MD, New York, NY. Stanley G.

Cooper, MD. Wen Yi Wang, MD. Patricia Hyunho

Choi, MD. Rajesh Ishverbhai Patel, MD. Israel Schur,MD

PURPOSE: To evaluate the technical success, infection,and interl'entional procedure rates for the Schon catheterand to compare with the SoftCell catheter.

MATERIALS AND METIIODS: The interventional registry,radiologic reports, and laboratory data were collected for77 patients with end-stage renal disease (ERSD) whoreceived either a Schon or a SoftCell tunneled hemodi­alysis catheter during a 10-month period. All catheterplacements were performed by Interventional Radiologystaff and trainees utilizing real-time ultrasound-guidedneedle puncture and fluoroscopic-guided placement.

RESULTS: A total of 35 of 37 Schon catheters weresuccessfully inserted in 34 patients for a technicalsuccess rate of 94.6% compared with 97.5% for the