Karim Valji

Pulmonary Embolism from PulseSpray Pharmacomechanical Thrombolysis of Clotted Hemodialysis Grafts: Urokinase versus Heparinized Saline

PURPOSE To compare the frequency and extent of pulmonary embolism (PE) occurring during pulse-spray pharmacomechanical thrombolysis (PSPMT) of clotted hemodialysis grafts with use of either urokinase (UK) or heparinized saline (HS). Postintervention primary patency and complication rates were compared for each method of thrombolysis. METHODS AND MATERIALS Twenty-seven patients were enrolled in this prospective, randomized, double-blind study evaluating PE with two PSPMT agents. The doses of heparin were similar between groups. The only variable was that one group of patients received UK and the other received HS. In two cases, the venous anastomosis could not be crossed. Eleven patients were treated with UK and 14 with HS. Nuclear medicine perfusion lung scans were performed before treatment and after graft declotting procedures. Lung perfusion was quantified to 10% of a pulmonary segment (0 = normal perfusion, 1 = segmental perfusion defect), with nine segments counted for each lung. RESULTS Baseline nuclear medicine perfusion lung scan results were abnormal (> or = 20% segmental perfusion defect) in 19 patients (70.4%). New PE (one or more pulmonary segments) occurred in two patients treated with UK (18.2%) and nine patients treated with HS (64.3%; P = .04). All cases of PE were asymptomatic. Quantitative global pulmonary perfusion analyses revealed that treatment with UK improved flow to 0.2 +/- 2.0 pulmonary segments, whereas treatment with HS decreased perfusion to 1.0 +/- 1.7 segments (P = .16, NS). Although postintervention primary patency rates were similar according to life-table analysis (P = .76, NS), complication rates were higher with use of HS (n = 4, 28.6%) than with use of UK (n = 2, 18.2%) (P = .6, NS). CONCLUSIONS All PE were asymptomatic during PSPMT, but treatment with UK reduced the rate of PE and tended to result in smaller defects in lung scan results. Most patients undergoing hemodialysis have abnormal baseline perfusion scan results, but PSPMT with UK improved many of them. The postintervention primary patency rates were similar between groups, but complications were more frequent after treatment with HS.

Evolving Strategies for Thrombolytic Therapy of Peripheral Vascular Occlusion

Abbreviations: FDA Food and Drug Administration, PAO peripheral arterial occlusion, rt-PA recombinant tissue-type plasminogen activator, SK streptokinase, UK urokinase CHARLES Dotter first described a technique for regional infusion of fibrinolytic agents a quarter century ago. Since then, thrombolytic therapy has become an integral part of the management of patients with acute peripheral vascular occlusive disease in native arteries and bypass grafts, hemodialysis grafts, extremity veins, and other sites. For the last 15 years, urokinase (UK) has been the thrombolytic drug of choice in the United States because of its proven efficacy, excellent safety profile, and low cost compared to most other available agents. The recent removal of UK from the marketplace by the United States Food and Drug Administration (FDA) has caused widespread confusion among interventional radiologists faced with performing thrombolytic therapy with use of alternative thrombolytic drugs. The purpose of this article is to review the currently available fibrinolytic agents, explain the withdrawal of UK, examine the published experience with other fibrinolytic agents in peripheral vascular occlusions, and suggest a rational approach to thrombolytic treatment at the beginning of the new century.

Pulse-spray pharmacomechanical thrombolysis

The synergistic potential of combining pharmacologic and mechanical methods of thrombolysis has recently been recognized. Pulse-spray pharmacomechanical thrombolysis is one such method, which in our experience has markedly increased the efficiency and acceptability of thrombolysis. With this technique, dialysis grafts usually require only 20–35 min for thrombolysis; bypass grafts or native arteries usually require 60–150 min. The entire procedure is accomplished in one session within the angiography suite, including the supplemental transluminal angioplasty, atherectomy, or stenting that is usually also necessary. Clear understanding of the principle of the method and meticulous attention to technical details is essential for maximal speed, safety, and efficacy.

Pharmacoarteriography in the evaluation of impotence

Progress in diagnosis and therapy of impotence is handicapped by the absence of a validated and objective method for evaluating the vascular system; a gold-standard for vasculogenic impotence is needed. Prior experience has indicated that conventional arteriography in unanesthetized patients is unreliable in evaluation of the penile arterial supply. We have improved our arteriographic methods by the routine application of selective pudendal injections, vasodilation pharmacoangiography with nitroglycerin and papaverine, and direct magnification. Experience in 37 impotent patients demonstrates marked improvement in the quality of visualization of distal vessels, and the frequent presence of functional vasoconstriction of medium and small arteries that can be distinguished from organic disease only with vasodilators. We believe these angiographic methods will improve the criteria against which other diagnostic and therapeutic methods can be objectively assessed.

Is thrombolysis of occluded popliteal and tibial bypass grafts worthwhile

PURPOSE We analyzed the short- and long-term results for patients undergoing thrombolysis of occluded infrainguinal bypass grafts at our institution over a 62-month period. METHODS Thirty-one patients with 40 episodes of graft thrombosis in 33 grafts managed by thrombolysis were retrospectively reviewed. The effects of graft age, material, and anatomy, symptoms, treatment, anticoagulation, and occlusion duration were evaluated for impact on patency after thrombolysis. Dose and duration of therapy with use of the technique of pulse-spray thrombolysis was assessed. RESULTS Thrombolysis successfully reestablished patency in 92% of grafts treated. Mean lysis time and urokinase dose were 118 minutes and 607,000 units, respectively. Responsible lesions were identified and treated by angioplasty or surgery in 35 of 37 cases. The patency rate after thrombolysis was 28% at 30 months, and the secondary patency rate was 46% at 18 months. Duration of occlusion, symptoms, treatment, graft anatomy, and prior graft revision did not impact on patency. Mean secondary patency was 21.5 months in grafts in place over 1 year and 7.0 months in grafts in place for less than 1 year. Mean secondary patency was 23.8 months in polytetrafluoroethylene grafts and 8.4 months in vein grafts. The limb salvage rate was 84% at 30 months, and the patient survival rate was 84% at 42 months. CONCLUSIONS Pulse-spray thrombolysis is effective in rapidly recanalizing thrombosed infrainguinal grafts. Grafts failing in the first year after placement should generally be replaced, reserving thrombolysis and revision for grafts greater than 1 year old. Vein grafts tolerate thrombosis less well than synthetic conduits and have decreased long-term patency.

IVC Filter Tilt and Asymmetry: Comparison of the Over-the-Wire Stainless-Steel and Titanium Greenfield IVC Filters☆

PURPOSE A comparison of tilting, caval coverage, asymmetry, and insertion problems with the over-the-wire stainless-steel and titanium versions of the Greenfield filter. MATERIALS AND METHODS The study compared 104 stainless-steel and 141 titanium Greenfield inferior vena cava (IVC) filter insertions. The angle the sheath and deployed filter made relative to the cava, as well as filter strut distribution, were determined from spot films. The proportionate caval coverage was computed from the cavogram (anteroposterior projection). Mean filter tilts, subgrouped by insertion site, and caval coverage were compared with the Student t test, whereas strut patterns were analyzed with a contingency table. RESULTS The filter caval and sheath caval angles correlated. The filter caval angles varied with insertion site, but were lowest with a right jugular approach. Caval coverage was identical with both designs. The stainless-steel version resulted in a more uniform distribution of struts in comparison with the titanium version. The incidence of insertion problems was not significantly different between the filter types. CONCLUSIONS While IVC filter tilting was not improved with the newer design, the pattern of struts was more uniformly symmetric with the stainless-steel device. The right jugular insertion site was associated with the lowest filter caval angles and the most symmetric pattern of struts.

Safety and Efficacy of Drug-eluting Bead Chemoembolization for Hepatocellular Carcinoma: Comparison of Small-versus Medium-size Particles

PURPOSE To compare safety and imaging response with 100-300 μm and 300-500 μm doxorubicin drug-eluting bead (DEBs) to determine optimal particle size for chemoembolization of hepatocellular carcinoma (HCC). MATERIALS AND METHODS DEB chemoembolization using 100-300 μm (n = 39) or 300-500 μm (n = 22) LC beads loaded with 50 mg of doxorubicin was performed in 61 patients with HCC. Patient age, sex, etiology of liver disease, degree of underlying liver disease, tumor burden, and performance status were similar between the groups. All treatments were performed in a single session and represented the patients first treatment. Toxicities and imaging response in a single index tumor were analyzed using World Health Organization (WHO) and European Association for the Study of the Liver (EASL) criteria. RESULTS There was a significantly lower incidence of postembolization syndrome and fatigue after treatment in the 100-300 μm group (8% and 36%) versus the 300-500 μm group (40% and 70%) (100-300 μm group, P = .011; 300-500 μm group, P = .025). Mean change in tumor size was similar between the two groups based on WHO and EASL criteria and similar rates of objective response, but there was a trend toward a higher incidence of EASL complete response with 100-300 μm beads versus 300-500 μm beads (59% vs 36%; P = .114). CONCLUSIONS In DEB chemoembolization for treatment of HCC, 100-300 μm doxorubicin DEBs are favored over 300-500 μm doxorubicin DEBs because of lower rates of toxicity after treatment and a trend toward more complete imaging response at initial follow-up.

Quality Improvement Guidelines for Percutaneous Management of Acute Limb Ischemia

Dheeraj K. Rajan, MD, FRCPC, Nilesh H. Patel, MD, Karim Valji, MD, John F. Cardella, MD, Curtis Bakal, MD, Daniel Brown, MD, Elias Brountzos, MD, Timothy W.I. Clark, MD, Clement Grassi, MD, MSc, Steven Meranze, MD, Donald Miller, MD, Calvin Neithamer, MD, Kenneth Rholl, MD, Anne Roberts, MD, Marc Schwartzberg, MD, Timothy Swan, MD, Patricia Thorpe, MD, Richard Towbin, MD, and David Sacks, MD, for the CIRSE and SIR Standards of Practice Committees

Adjunctive 3D US for Achieving Portal Vein Access during Transjugular Intrahepatic Portosystemic Shunt Procedures

PURPOSE To evaluate the usefulness of information provided by three-dimensional ultrasound (3D US) and to determine whether 3D US decreased the number of passes required to obtain portal vein (PV) access during creation of transjugular intrahepatic portosystemic shunts (TIPS). MATERIALS AND METHODS Intermittent 3D US volume acquisitions were obtained during creation of TIPS in 20 patients. Useful information provided by 3D US was tabulated. The number of passes required to achieve PV access was recorded and results were compared retrospectively to 25 patients who underwent TIPS without 3D US. RESULTS 3D US documented that the operators opinion of which hepatic vein had been selected was incorrect in nine patients (45%), detected unfavorable PV anatomy that required modification of equipment or technique in seven patients (35%), permitted estimation of the trajectory required to access the targeted PV in all patients (100%), assisted in selecting the optimal point along the hepatic vein for origination of the needle pass in 11 patients (55%), allowed avoidance of a large hepatocellular carcinoma in one patient (5%), and confirmed that access into the main PV was intrahepatic in four patients (20%). The mean number of needle passes decreased from 10.4 in the historic control group to 4.6 in the 3D US group (P = .0001). CONCLUSION 3D US provided imaging information that detected technical errors and altered anatomy, and provided positional and directional information to significantly improve needle pass efficiency.

Transluminal angioplasty in the treatment of arteriogenic impotence

Factors bearing on the role of transluminal angioplasty in the management of arteriogenic impotence are considered. Our clinical experience indicates that arteriogenic impotence is frequent, either alone or combined with venogenic impotence. High quality diagnostic angiographic studies and their accurate interpretation are the prime requirements for proper patient selection. Numerous areteriographic adjuncts are required: vasodilation with intracavernosal injection of a papaverine-phenotolamine mixture, selective internal pudendal injections, direct magnification, nonionic contrast agents, and tailored radiographic projections. Venogenic impotence must be excluded by cavernosometry and cavernosography. In impotent patients with bilateral leg and hip claudication, dilation of common or internal iliac stenoses should benefit many cases with pure arteriogenic impotence. In the absence of claudication, angioplasty will be most frequently indicated for distal internal pudendal lesions, using 2–3 mm balloon-catheter systems. Stenoses of intrapenile branches, while common, must await further technological developments before they too may become amenable to transluminal recanalization. Unilateral transluminal angioplasty, when technically successful, should prove clinically successful when patients have been properly selected. Transluminal angioplasty can reduce the cost and morbidity of penile revascularization and may assume a modest role in the treatment of arteriogenic impotence.