1995 SCVIR Annual Meeting Notes Scott J. Savader, MD, Johns Hopkins Hospital, Baltimore, Maryland James N. Driesbach, JD, Radiology Imaging Association, Englewood, Colo John D. Reed, MD, Parkview Memorial Hospital, Ft. Wayne, Ind Robert B. Sanchez, MD, Presbyterian Hospital, Albuquerque, New Mexico Michael C. Soulen, MD, Hospital of the University of Pennsylvania, Philadelphia, Pa James B. Spies, MD, Sibley Memorial Hospital, Washington, DC Scott 0. Trerotola, MD, Indiana University School of Medicine, Indianapolis, Ind Anthony C. Venbrux, MD, Johns Hopkins Hospital, Baltimore, Md Peter N. Waybill, MD, Penn State University Hospital, Hershey, Pa David M. Widlus, MD, Sinai Hospital of Baltimore, Baltimore, Md Adam B. Winick, MD, George Washington Hospital, Washington, DC
JVIR 1995; 6:651456 O SCVIR,
THE 1995 Annual Meeting of the Society of Cardiovascular and Interventional Radiology was again excellent and continues to grow yearly. One thousand five hundred twelve physicians attended along with 168 spouses. The Association of Vascular and Interventional Radiographers and American Radiological Nurses Association had over 365 attendees. The exhibitors totaled 1,756 individuals, for a total attendance of 3,721. Managed care and cost-containment issues were popular topics of conversation on the exhibit floor, and many of the abstracts presented discussed cost-effectiveness issues. The sun and fun of Ft. Lauderdale however lifted even these heavy clouds and made for a very enjoyable meeting. STENT GRAFTS AND STENTS Stent Grafts Katzen et a1 presented initial results on eight patients who received predominantly aortoiliac stent grafts. This study demonstrates that with important factors addressed, such as proper room air handling, room preparation, scrub location, anesthesia, sterile technique, and room traffic patterns, the interventional suite can function as an appropriate location for this complex procedure as opposed to the need for an operating room. Katzen et a1 also presented data on the Endovascular Technologies Endograft Multicenter Trial for treatment of abdominal aortic aneurysms. Fifteen patients have been treated to date, and initial data indicate that the complication rate and length of hospital stay in the percutaneous group are considerably lower than those for patients undergoing conventional surgery. Dake et a1 presented data on a self-expanding stent graft consisting of Z stents with a Dacron covering that was used in 36 patients with thoracoabdominal aneurysms. Complete aneurysm thrombosis was achieved in 33 cases (92%). Cynamon et a1 presented data on stent-graft repair of long- segment aortoiliac disease. Their stent graft was constructed from 6-mm polytetrafluoroethylene and Palmaz stents. At a mean follow-up of 8.5 months, a 73% patency rate was achieved. Martin et a1 presented data on a Dacron Y graft
Journal of Vascular and Interventional Radiology
for aortobiiliac disease. Although the initial thrombosis rate approached loo%, this has been decreased to 0% by placement of Wallstents within the graft limbs. Four French groups presented initial data on the Cragg Endopro System 1stent graft. Follow-up in these studies ranged from 3 to 11months with primary patencies of 100% and secondary patencies at the iliac level of 100% and femoral level of 88%.
Peripheral Stents Westcott et a1 presented data from the STAR Registry on 23 patients treated for infrarenal aortic stenoses with percutaneous transluminal angioplasty (PTA)(n = 12) versus the Palmaz stent (n = 11). Early data would suggest that the Palmaz stent has improved short-term clinical results versus PTA in the aorta. Results of the U.S. Food and Drug Administration (FDA)trial of the Wallstent were presented by Dr Martin. One hundred thirty-nine patients were treated for iliac disease and 90 for femoral disease with this device. In the iliac system, the 6- and 12month primary patencies were 90% and 78%, respectively, with a mean increase in the ankle-brachial index (ABI) from 0.64 to 0.86. For the femoral vessels, the 6- and 12-month primary patency rates were 73% and 54%, respectively, with an increase in the ABI from 0.69 to 0.96. Henry et a1 discussed utilization of the Palmaz stent in both iliac and femoropopliteal vessels. One hundred eighty-eight stents were placed in the femoral-popliteal position with followup obtained at 4 years. The primary patency rates were 88%, 67%, and 44% for the upper third of the superficial femoral artery (SFA), midportion of the SFA, and lower third of the SFA and popliteal artery, respectively. Venous and Renal Stents Kee et a1 presented data on treatment of superior vena cava syndrome with stents. Patients underwent initial thrombolysis followed by PTA and stent placement. Eighteen patients died symptom free after a mean period of 6.3 months. The remaining 17 patients with malignant disease demonstrated a primary and secondary patency of 76% and 96%, respectively. Data from a multicenter trial on use of the Palmaz-Schatz stents in the renal artery were presented by Rees et al. Two hundred sixty-three patients were treated. The cumulative cure rate for hypertension ranged from 91% a t 1month to 61% a t 12 months. Renal insufficiency was improved in 34%. Restenosis was documented in 32.7% of patients. Gastrointestinal and Tracheobronchial Stent An interesting paper was presented by Herrera et a1 on use of a metallic endoprosthesis for the treat-
ment of lower intestinal obstruction. Ten patients underwent placement of an expandable metallic prosthesis followed by definitive operation 6-7 days after implantation of the prosthesis. Placement of this presurgical stent allowed for one-step surgery with creation of an end-to-end anastomosis, thus avoiding the creation of a temporary colostomy. Watkinson et a1 presented data on 30 patients with malignant esophageal obstruction who underwent insertion of a polyurethane covered Wallstent, Nitinol Strecker stent, or polyethylene covered Gianturco stent. The technical success rate was 100% and all patients could subsequently eat a relatively normal diet. The mean hospital stay following stent insertion was 4.4 days. The complication rate was 10%.
DIALYSIS ACCESS INTERVENTIONS AND CENTRAL VENOUS ACCESS Dialysis Access Intervention Bourgeois et a1 presented information on a series of interventions in failed or failing native fistula in 45 patients. In patients who underwent PTA alone, the primary patency ranged from 93% a t 1month to 60% at 9 months. In those who underwent PTA and thrombolysis, the primary patency ranged from 92% at 1month to 50% a t 9 months. These are important data, as interventions in native fistula are not widely reported. Lund et a1 presented a series of 26 stent placements in hemodialysis patients (seven peripheral and 19 central). The stents were all placed for PTA failure. The cumulative probability of primary patency at 6 and 12 months for the central stents was 57% and 29%, respectively, while for the peripheral stents it was 42% and 42%, respectively. Trerotola et a1 presented a very interesting paper describing percutaneous creation of arteriovenous dialysis grafts in a canine model with use of stent grafts. The authors used silicone-coveredWallstents to form mostly femoral loop grafts. The "anastomoses" were hemostatic, but dislodgment occurred when the animals awoke from anesthesia, indicating some form of furation device will be needed. This technique could be applied to graft revision, de novo graft creation, and also extraanatomic femoral-femoral arterial bypass grafts. Amygdalos et a1 presented their data on percutaneous mechanical declotting in 59 patients. Balloon thrombectomy was the only technique used, with clinical success achieved in 71% of patients. A single major complication occurred-a death from a probable septic pulmonary embolism. This patient did not receive prophylactic antibiotics, and the authors stress that graft thrombolysis should not be performed in patients with suspected graft infection. Uflacker et a1 presented the results of an FDA-approved clinical trial of the Amplatz mechanical
1995 SCVIR Meeting Notes
Volume 6 Number 4
versus 0% and 0% for the TIPS group. At a mean of 1-year follow-up, the mortality and encephalopathy rates were similar in both groups. Kerlan et a1 reported on a method for TIPS shunt occlusion. This group described five patients who developed uncontrollable, disabling encephalopathy following the creation of a TIPS shunt. An 11.5-mm-diameter latex occlusion balloon was inflated within the midportion of the shunt for a minimum of 12 hours. Shunt thrombosis was successful in all five patients. Encephalopathy resolved in four patients and improved in one.
thrombectomy device in dialysis access grafts. Twenty-six patients were enrolled with 14 in the device group. Thirty-day primary patency was approximately 50%. Walser et a1 presented their results with "hybrid therapy of dialysis graft declotting (urokinase plus balloon declotting). A cost analysis compared with surgical thrombectomy showed the hybrid approach to average $4,500 while the surgical approach averaged $6,500.
Central Venous Catheters Rosenblatt et a1 presented data on interventional placement of chest wall ports. One hundred fifty-four patients had 146 infusion ports placed with 100% technical success rate. The overall complication rate was 0.7% per 1,000 indwelling catheter days. Haskal et a1 presented a n interesting paper documenting the inefficacy of fibrin sheath stripping from clotted catheters. Twenty-three procedures were performed in 17 patients with a technical success rate of 91%. The improvement in hemodialysis was suboptimal in all patients and within 14 days of stripping, five catheters required replacement and 13 had been treated with urokinase. TRANSJUGULAR INTRAHEPATIC PORTOSYSTEMIC SHUNTING (TIPS) Ring et a1 report on a randomized study of TIPS versus sclerotherapy for control of bleeding esophageal varices. In 18 patients from the sclerotherapy group versus 16 patients in the TIPS group, the rebleeding rate and procedural crossover rate in the sclerotherapy group was 39% and 17%, respectively,
THROMBECTOMYIARTERIAL AND VENOUS THROMBOLYSIS Thrombectomy Rousseau et a1 presented data on the new 7-F double-lumen hydrodynamic thrombectomy catheter called the Hydrolyser. This device was tested in arterial grafts, native arteries, and hemodialysis shunts in 16 patients. Declotting was achieved in less than 15 minutes. Complete success was achieved with the Hydrolyser alone in 11cases. Pozza et a1 reported on their testing of the 8-F Amplatz thrombectomy device. The study was performed in eight dogs with iatrogenic inferior vena cava thrombosis. Following use of the Amplatz thrombectomy device, blood flow was reestablished in all eight dogs. 0, saturation dropped by 6%, and the mean pulmonary arterial pressure increased by 3.5 mm Hg. Arterial Thrombolysis Sato et a1 presented data on the effects of multiple intrathrombotic wedge infusions of high-dose urokinase in chronic arterial occlusions which failed the guide-wire passage test. The initial complete recanalization rate was 80%, and the 1-year patency rate was 68%. This study does show that failure of the guide-wire traversal test does not necessarily preclude thrombolytic recanalization. Valji et a1 reported on arterial pulse-spray thombolysis in 52 arterial occlusions treated with a mean urokinase dose of 515,000 IU. Mean time for lysis was 98 minutes. Successful recanalization with improved lower extremity blood flow was achieved in 94% of cases. Venous Thrombolysis Jaffe et a1 presented a n interesting report on the use of catheter-directed thrombolytic therapy for 19 patients with iliofemoral deep venous thrombosis and phlegmasia cerulea dolens. A bolus and continuous infusion technique was used. Eighteen (95%) patients had greater than a 50% lysis with significant resolution of symptoms including decreased pain and swelling. Only one patient (5%)demonstrated only minimal lysis. After a mean follow-up of 12%
Journal of Vascular and Interventional Radiology
months, 16 patients are symptom free and three have class I venous insufficiency. Semba et a1 presented data on thrombolytic therapy for chronic iliac venous thrombosis. Thirteen patients with a mean symptomatic period of 1year underwent catheter-directed thrombolytic therapy. Lysis was complete in 15% of patients, partial in 77%, and no results were seen in 7%. Nine patients required stent placement following completion of thrombolysis.
CANCER INTERVENTIONS AND EMBOLIZATION Cancer Intervention and Chemoembolization Casola et a1 reported on 300 patients with mostly stage A and B prostatic carcinoma who were treated with cryoablation of the prostate. Ninety percent of patients had negative results a t prostate biopsies 3-6 months later. Intraoperative ultrasound was used to guide cryoablation for liver tumors in 62 patients in a study by Cain et al, with actuarial survival similar to that achieved by means of resection. Four DaDers addressed chemoembolization of hepatomas with a variety of embolic agents including iodized oil, iodized oil and Gelfoam, degradable starch microspheres, and bovine collagen fibers. Response rates were 50%-64%. Jaeger et al compared outcomes to that for surgical resection and found similar survival in both groups. An important technical paper by Hanks et a1 reporting 665 procedures over 7 years demonstrated that superselective, segmental chemoembolization is associated with a significantly higher complication rate than if the catheter is left in the proximal hepatic artery (35% vs 7%), as well as significantly longer hospitalization (4.6 vs 1.3 days). There was no difference in response or survival between the two groups. Two presentations (Soulen et a1 and the workshop by Clouse and Dawson) provided survival data for patients with liver metastasis from colon cancer in whom systemic therapy failed and who subsequently underwent chemoembolization with an iodized oiVparticle regimen. Both showed 1-year actuarial survival near 67%. These data are the first indication that chemoembolization may prolong survival in this disease. 1
Venous Embolization Zuckerman presented a review of male varicocele pathophysiology in his plenary session presentation. Embolization carries a technical success rate of about 72%; however, pregnancy is achieved in only about 60% of couples. O'Grady et a1 subsequently presented their data on embolization of recurrent postsurgical varicoceles. The technical success rate was 100%in 20 individuals. Follow-up in 15 men at 7 4 4 months revealed a 33% fertility rate but no pregnancies.
Le Blanche et a1 provided data on a retrospective study of 500 spermatic venograms. From the left and right gonadal veins, respectively, there was a 10.2% and 28.2% incidence of anastomoses to portal veins. Machan presented information on ovarian vein embolization for pelvic pain in women. This remains controversial, but there is a substantial number of women whose symptoms are reversed following occlusion of ovarian vein varicoceles. Dr Machan reported on 22 procedures with marked improvement or complete relief in 16.
Embolization for Visceral and Traumatic Hemorrhage Duszak et a1 presented data from an interesting study on transcatheter embolization in the management of upper gastrointestinal hemorrhage. In 52 patients undergoing 56 procedures, clinical control of bleeding was achieved in only 54% of individuals. Interestingly, clinical success was achieved in 34% of individuals with a coagulopathy versus 79% without a coagulopathy. The embolic agent, location of the arterial hemorrhage, and presence or absence of extravasation did not affect the success rate. Despite their technical success rate of 96%, the overall hospital mortality rate was 39% (coagulopathic, 66%, noncoagulopathic, 4%). INFERIOR VENA CAVA FILTERS Irie et a1 and Krysl et a1 presented papers on Irie's new, rather ingeniously designed, retrievable vena caval filter. If retrieval is necessary, the filter is snared from both the proximal and distal ends, with tension on the snares resulting in separation of the filter into two units that are retrieved separately. The filter can be removed after 30 days without difficulty. BIOPSY AND PERCUTANEOUS DRAINAGE Biopsy Murphy et a1 presented data on the etiology of false-negative findings a t percutaneous liver biopsies in 553 cases. They identified the most significant factor in a false-negative biopsy as the absence of a known primary. In addition, lymphoma and sarcoma were noted to be associated with an increased incidence of false-negative biopsies. This is interesting, as Sheley et a1 presented their data on needle biopsy in the diagnosis of lymphoma. Thirty-eight patients underwent biopsy (with a cutting needle in 36 and aspiration needle technique in two) with an 82% accuracy rate. Percutaneous Drainage Sawhney et a1 presented data from 10 patients with persistent postoperative lymphoceles. Catheter drainage was effectively achieved in all patients.
1995 SCVIR Meeting Notes
Volume 6 Number 4
BILIARY DISEASE An interesting presentation on the closure of biliary fistulas was given by Bjarnason et al. Twelve patients, 11with liver transplant T-tube tracts that were leaking into the peritoneal cavity, underwent embolization with metallic coils. The fistulas usually closed within minutes or, a t the longest, within 2-3 days. No complications were reported.
Seven underwent sclerotherapy with absolute alcohol a t 10-50 ml/sec in one to three sessions per day. Resolution of lymphoceles was achieved in 80% of the patients with two recurrences. A valuable cost-effectiveness study comparing percutaneous endoscopic, surgical endoscopic, and percutaneous radiologic gastrostomy/gastrojejunostomy in 116 patients was presented by Barkmeier et al. Success rates were 88%, loo%, and 100% for the three techniques, respectively. The complication rates were similar in all groups, and the cost for the initial procedure was approximately $1,800 for the percutaneous radiologic technique versus $1,600 for the percutaneous endoscopic and $2,300 for the surgical endoscopic techniques. While the percutaneous endoscopic technique was the least expensive modality, the lower success rate and requirement for a subsequent procedure in many patients may reduce its overall cost-effectiveness. Percutaneous radiologic gastrostomy proved safe, effective, and relatively inexpensive.
ANGIOGRAPHIC TECHNIQUES There were two presentations on carbon dioxide angiography by the University of Florida group, one by Young et a1 and a second by Hawkins et al. Carbon dioxide was injected through a 3-F or 4-F catheter in the performance of 25 examinations in patients with renal reimplantation after vascular bypass. Visualization of the anastomosis was good, and secondary and tertiary branches of the kidney were seen in all patients. No complications were incurred. In the second study, 15 patients with renal transplants underwent a similar procedure and there was good visualization of the anastomosis and third- to fifth-order branches in all patients. Dr Hawkins suggests a 5-minute delay between injections to allow dissolution of the gas, thus avoiding ischemia secondary to a "vapor lock." Three papers were presented on magnetic resonance (MR) angiography of the aortoiliac and lower extremity vessels. Holland et a1 compared contrastenhanced three-dimensional (3D) and two-dimensional (2D) time-of-flight (TOF) techniques for evaluation of the aortoiliac system: 2D TOF had a sensitivity of 100% and specificity of 75%. while 3D TOF % specificity of 91%. had -a sensitivity of ~ O Oand Snidow et a1 presented their results on interpretations and treatment decisions based on 2D TOF MR angiography compared with conventional angiography in 42 patients with symptomatic lower extremity ischemia. The authors state that the treatment plan based on the 2D TOF data matched that based on arteriography in only 41% of cases. The findings of this study are in contradistinction to a study presented by Baum et a1 in which peripheral vascular surgery was based on MR angiography as the sole preoperative imaging study in 80 consecutive bypass candidates. There was a 97% agreement between the preoperative MR angiographic findings and the operative findings. ANGIOPLASTY In this cost-conscious environment, data on outpatient PTA were supplied by Rundback et a1 based on their study of 63 patients undergoing 93 procedures (62 infrainguinal). Patients were followed up for 5-6 hours. Eleven admissions were required, three for complications and eight for planned additional intervention. Those patients discharged to home were re-
Journal of Vascular and Interventional Radiology
called a t 24 hours, and none of these patients required readmission or developed complications requiring further intervention. Hallisey et al discussed the role of PTA for mesenteric ischemia. Twenty-five stenoses in 16 patients were treated, with a technical success rate of 88%.The primary patency was 64%a t a mean of 2.3 years follow-up, and all patients were asymptomatic.
W A G E D CARE SYMPOSIUM Dr Dreisbach discussed practical aspects of managing a horizontal radiology network, emphasizing
the use of utilization review, third-party administration, and quality assurance. Mr David Zacks gave an excellent discussion on forming multispecialty groups emphasizing the reasons why a n integrated delivery system is desirable. Dr Philip Cook discussed utilization review as a fundamental tool used to monitor care. One of the deficiencies in utilization review of this form is that it does not take into account which patients may be more or less sick and thus does not consider which patients may require more tests than others. James Spies discussed practice guidelines in a managed care system.