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Purpose: To assess the sensitivity of Doppler flow analysis of the axillary and internal jugular veins to screen for clinically occult thoracic central veno-occlusive disease and predict successful placement of central access catheters., Materials and Methods: Sixty-seven patients underwent both duplex sonographic evaluation of the axillary and internal jugular veins and contrast venography prior to placement of a central venous catheter. Duplex evaluation included visual evidence of veno-occlusive disease as well as the presence or absence of normal transmitted polyphasic atrial waves and respiratory variation of flow. Diagnostically adequate venograms were available for comparison with the duplex sonograms in 168 access routes (access site plus downstream conduit veins). The contrast venograms and sonograms were compared by using retrospective blinded interpretation. Outcome of attempted catheter placement was tabulated., Results: Directed sonographic imaging of the axillary and internal jugular vein allowed detection of access route veno-occlusive disease with a sensitivity of only 33.3%. Alternatively, when Doppler flow analysis found atrial waveforms that were not polyphasic, central conduit occlusive disease was detected with a sensitivity of 79.6%. Monophasic atrial waveforms were associated with a 25% failure rate of catheterization due to central vein occlusive disease, whereas polyphasic atrial waveforms were correlated with a 100% success rate for catheter placement., Conclusion: In asymptomatic patients, sonographic imaging alone misses most instances of central veno-occlusive disease. However, Doppler flow analysis of transmitted atrial waveforms substantially improved the sensitivity. A normal polyphasic atrial waveform virtually excludes the possibility of a more central venous occlusion or stenosis greater than 80% and ensures an adequate route for central venous catheterization.

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.

Purpose: To determine whether acute cervical spine injury represents a risk factor for complications from prophylactic placement of current generation Greenfield inferior vena cava (IVC) filters., Materials and Methods: A retrospective chart review performed during a 7-year period identified 11 patients with acute cervical spinal cord injuries who underwent prophylactic Greenfield IVC filter insertion. Specific complications evaluated included symptomatic pulmonary embolism (PE), migration, filter base diameter changes, caval perforation, and thrombosis. The amount of migration and changes in filter base dimension were compared statistically with a control population of IVC filter patients (n = 16) without cervical spine injuries., Results: Filter migration (> 10 mm) was the most common complication (46%). Migration usually is caudally directed (64%), may occur early (36% moved > 10 mm within a 30-day period), and is often asymptomatic. The prevalence of filter migration greater than 30 mm was 27%. The average amount of migration for the subpopulation under study was greater than that seen with the control population (P < .05). No statistically significant change in filter base size occurred. The study population also had rates of PE (9%-18%), caval perforation (9%), and IVC thrombus formation (18%) that were higher than the rates in historical controls. The majority of patients with these complications received vigorous pulmonary toilet (46%), including "quad coughs" or cardiopulmonary resuscitation (18%)., Conclusions: Acute cervical spinal cord injury and the associated supportive care may be associated with an increased risk for caudal IVC filter migration, IVC perforation, caval thrombosis, and PE.

Objective: Pulse-spray pharmacomechanical thrombolysis is an evolving method for the treatment of vascular occlusions in which a highly concentrated fibrinolytic agent is injected as a high-pressure spray directly into thrombus. The purpose of this retrospective study was to analyze our long-term experience with this technique for the treatment of clotted hemodialysis grafts and to compare the efficacy and safety of the original and current methods., Subjects and Methods: Over 6 years, 284 cases of dialysis graft thrombosis were considered suitable for treatment with pulse-spray thrombolysis. The original technique involved the injection of highly concentrated urokinase directly into a clot through two crisscross catheters with multiple side holes. The current technique includes early fragmentation of residual clot with a balloon catheter, intrathrombic injection of heparin, mechanical treatment of a lysis-resistant clot at the arterial anastomosis, and routine administration of aspirin. After thrombolysis, underlying obstructions were treated with balloon angioplasty, atherectomy, or stents. The technical success, immediate clinical success, and frequency of complications for the entire population were analyzed. In addition, the results for 36 cases treated with the original technique were compared with the results for 37 recent cases treated with the current technique., Results: Of 284 cases considered suitable for treatment, thrombolysis was not done in eight cases because the venous anastomosis could not be crossed. Thrombolysis was discontinued in two cases because of extravasation of contrast material. The technical success for all grafts considered for treatment was 96%; 92% of treated grafts remained patent for at least 24 hr. Major complications occurred in 1% of cases, and minor complications occurred in 9% of cases. The clinical efficacies of the original and current techniques were 86% and 92%, respectively. The mean thrombolytic agent infusion time was reduced from 44 +/- 20 min to 23 +/- 13 min (p < .001). The overall procedure time for the recently treated subgroup was 67 +/- 26 min. There was no significant difference in the frequencies of major and minor complications between the treatment subgroups., Conclusion: Pulse-spray pharmacomechanical thrombolysis is a reliable, rapid, and safe method for recanalization of occluded dialysis grafts. The current technique has been proven as safe and effective as the original technique but offers the advantage of a significant reduction in the time required for the infusion of thrombolytic agent.

Thrombosis of access grafts is a frequent problem for patients being treated with long-term hemodialysis. Transcatheter techniques have recently been used in the primary management of failed dialysis grafts. This article reviews current methods for transcatheter treatment. Several thrombolytic techniques are discussed, including pharmacologic, pharmacomechanical, and mechanical methods. Methods for treatment of underlying graft stenosis are considered. Complications associated with these procedures are reviewed. The percutaneous techniques are compared among themselves and with standard surgical procedures for graft revision. Finally, several evolving methods for prevention of dialysis graft thrombosis are considered.

Prolonging the life of vascular access sites is one of the most pressing problems facing the nephrology team in the ongoing care of chronic hemodialysis patients. Thus, the ability to salvage a failing vascular access is important in any circumstance, but salvage is particularly critical in medically complicated situations. The following case presents just such a situation, one in which available access sites were limited and in which salvaging the function of a local access site obviated the need for major surgical intervention for more than 4 years. This example shows the efficacy of nonsurgical thrombolysis and the place of vascular radiology in the long-term preservation of access patency and follow-up care.

Purpose: To evaluate the effectiveness of intravenous and intrathrombic injection of the thrombin inhibitor argatroban during pulse-spray pharmacomechanical thrombolysis (PSPMT) in experimental venous thrombosis., Materials and Methods: Clots were produced in the inferior vena cava in 52 rabbits by placement of steel coils and balloon injury to the vessel wall. Two days later, clots were treated with PSPMT. Several treatment methods were used: intrathrombic saline, intrathrombic tissue plasminogen activator (t-PA), intrathrombic t-PA with intrathrombic and intravenous heparin, intrathrombic t-PA with intravenous argatroban, and intrathrombic t-PA with intrathrombic and intravenous argatroban at two different doses. After treatment, the rabbits were killed and residual clot was weighed. Pretreatment clot weight was estimated and clot lysis was assessed., Results: PSPMT with t-PA and adjunctive intrathrombic heparin resulted in greater lysis than PSPMT with only t-PA (percentage of residual clot, 59% +/- 14 vs 81% +/- 28; P = .02). Addition of intravenous argatroban did not increase lysis, but adjunctive intrathrombic argatroban significantly increased lysis at low doses (37% +/- 16; P = .02) and high doses (34% +/- 6; P = .006) compared with t-PA and intrathrombic heparin., Conclusion: In a rabbit model of venous thrombosis, the use of intrathrombic argatroban during PSPMT with t-PA significantly improved clot lysis.

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.

Purpose: The problem of asymmetric opening of the modified hook titanium Greenfield inferior vena cava filter necessitating transcatheter manipulation was evaluated in a retrospective study., Patients and Methods: Titanium Greenfield filters were placed in 166 patients over a 36-month period. The radiographic reports of all patients were reviewed to identify cases in which the filter failed to open symmetrically after deployment and catheter or wire manipulation of the filter was performed. The reports and angiograms from these patients were reviewed with respect to the circumstances surrounding filter placement and methods to achieve more symmetric opening., Results: Transcatheter manipulation of asymmetrically opened filters was performed in 15 of 166 cases (9%). In 12 of these patients, acceptable and uneventful opening of the filter was achieved with a guide wire, pigtail catheter, or occlusion balloon catheter. In one case manipulation only partly improved orientation of the limbs, while in another case successful manipulation was complicated by distal migration. In the final case, the asymmetric filter covered only part of the lumen of the vena cava despite manipulations and a second filter was placed for optimal caval interruption. No specific cause for incomplete expansion was identified in any case., Conclusion: Marked asymmetry in opening of the modified hook titanium Greenfield filter that warrants manipulation occurs infrequently, but recognition and proper management may be important to ensure optimal caval interruption.

The results of pulse-spray pharmacomechanical thrombolysis (PSPMT) of 209 thrombosed hemodialysis grafts were reviewed. In PSPMT, concentrated urokinase is injected forcefully through catheters with multiple tiny sideholes or sideslits. Catheters placed in a crisscross fashion cover the entire clot simultaneously. This therapy was successful in treating patients with thrombosed grafts. Of the 200 grafts with complete therapy, 197 grafts (99%) were patent at the end of the procedure. Mean time for pulsed-spray lysis was 40 minutes. Etiologies for graft thrombosis were anastomotic venous outflow stenosis, stenosis of the venous outflow away from the anastomosis, arterial stenosis, intragraft stenosis, pseudoaneurysms, and no identifiable cause in a small percentage. There were 16 complications, 8 of which required additional therapy or potentially compromised the graft. These results suggest that pharmacomechanical thrombolysis and angioplasty provide rapid, consistent, and safe recanalization of thrombosed hemodialysis grafts and represent an additional therapeutic approach to graft management.

Objective: The results of duplex sonography of the cavernosal artery were compared with the results of pharmacoarteriography in a series of impotent men in order to assess the validity of sonography as a screening tool for the diagnosis of arteriogenic impotence., Subjects and Methods: Duplex sonography was performed in 30 impotent men after intracavernosal injection of papaverine and phentolamine. Maximal acceleration, peak systolic velocity, and resistive index were determined for the cavernosal artery. All patients had selective pharmacoarteriography and cavernosometry, which were used to diagnose arterial disease (bilateral hemodynamically significant stenoses or occlusions), suspected arteriolar dysfunction (inconspicuous helicine arterioles), or venoocclusive insufficiency (pharmacologic maintenance erectile flow greater than 25 ml/min). Seventeen patients had arterial insufficiency, four had arteriolar dysfunction, and nine had no significant arterial disease., Results: Significant differences in Doppler measurements were found between patients without significant arterial disease and those with arterial insufficiency, including peak systolic velocity (50 +/- 25 cm/sec vs 33 +/- 17 cm/sec, p = .04), acceleration (524 +/- 261 cm/sec2 vs 199 +/- 111 cm/sec2, p < .001), and resistive index (88 +/- 12% vs 73 +/- 11%, p = .002). Differences were also noted between the group without significant arterial disease and the group with arteriolar dysfunction. When peak systolic velocity of less than 25 cm/sec or acceleration less than 400 cm/sec2 was used as an indication of inadequate arterial patency, the sensitivities were 35% and 100%, the specificities were 61% and 46%, and the negative predictive values were 42% and 100%, respectively, in the diagnosis of arterial insufficiency., Conclusion: Duplex sonography of the cavernosal arteries may be a useful screening tool in patients with suspected arteriogenic impotence only when acceleration is evaluated in addition to peak systolic velocity. The specificity of the method may be partially limited by the inability to distinguish between arterial and arteriolar disease.

Rationale and Objectives: The efficacy and speed of pharmacomechanical thrombolysis may be limited by thrombotic effects of activated platelets and thrombin within the lysing clot. The authors designed an animal model of subacute venous thrombosis which was used to evaluate the effect of intrathrombic versus intravenous heparin during thrombolysis., Methods: Inferior vena cava (IVC) thrombosis was induced in rabbits by balloon catheter injury and placement of steel coils. Venacavagrams were obtained 48 hours later to document clot formation and for angiographic estimation of clot volume. Pulse-spray thrombolysis was performed by forceful injections of various agents through a catheter with multiple side holes spanning the clot. Most animals were given aspirin (30 mg orally) before treatment. After 1 hour of therapy, repeat venacavography was performed. Animals were killed, and residual clot weight was determined., Results: Occlusive IVC thrombi were present in 94% of rabbits at 2 days. Mean residual clot weight per milliliter of estimated initial clot volume (mg/mL) for the various treatment groups was as follows: saline (n = 5) 632 +/- 54; tissue-type plasminogen activator (t-PA) 3 mg, (n = 6) 443 +/- 162; t-PA 3 mg + heparin 750 U intravenously, (n = 7) 408 +/- 128; t-PA 3 mg + heparin 500 U intrathrombic + heparin 250 U intravenously, (n = 8) 213 +/- 166. Differences among these groups (except t-PA alone versus t-PA + intravenous heparin) were significant. The extent of lysis with intrathrombic + intravenous heparin was not significantly retarded by withholding aspirin (n = 6, 194 +/- 72), or improved by giving half the intrathrombic heparin before t-PA injections (n = 6, 280 +/- 158)., Conclusions: The results demonstrate the advantage of adjunctive intrathrombic + intravenous heparin over intravenous heparin alone in increasing the extent of pulse-spray thrombolysis in this IVC thrombosis model.

Pulsed-spray thrombolysis is accomplished through forceful injection of a spray of highly concentrated urokinase into clot by using catheters with multiple side holes. We previously reported the immediate technical efficacy of the method in eight arterial and 10 bypass graft occlusions. We now describe the clinical efficacy of the method in a second, larger series of 23 native artery occlusions and 25 bypass graft occlusions. Transluminal angioplasty was performed after thrombolysis in 21 of the arteries and 24 of the bypass grafts. Initial thrombolysis was observed in all artery occlusions and all but one bypass graft occlusion with an average time for pulsed-spray lysis of 65 +/- 28 min in native arteries and 93 +/- 38 min in bypass grafts. Recanalization with improvement in symptoms or distal pulses after thrombolysis and angioplasty was achieved in 74% of treated arterial occlusions and 92% of treated graft occlusions. Of the 15 arteries that were recanalized and did not require adjunctive surgery, seven remained patent at 3-28 months follow-up. Nine of 23 recanalized bypass grafts required early adjunctive surgery. Of the nine synthetic and five saphenous vein grafts successfully recanalized and not requiring surgical revision, the mean patency was 4.3 +/- 3.1 months and 3.0 +/- 2.2 months, respectively. Minor complications were seen in 23% of cases. The two major complications (4%) involved one groin hematoma requiring surgery and one episode of gastrointestinal hemorrhage. We conclude that combined pulsed-spray thrombolysis and angioplasty achieve rapid and consistent arterial and graft recanalization with minimal risk. The method offers a favorable alternative to standard thrombolytic therapy of arterial occlusions. In occluded synthetic and vein bypass grafts, the technique is sometimes beneficial, either alone or combined with surgical revision.

Within the past few years, veno-occlusion of the corpora cavernosa has become generally recognized as an essential prerequisite for adequate penile erection. Veno-occlusive incompetence is suspected to be a frequent cause of impotence. Our recent experience with cavernosography in two normal volunteers and 36 impotent patients indicates that angiography is reliable in evaluating the competence of the veno-occlusive mechanism only if both pharmacocavernosography (PCG) and pharmacocavernosometry (PCM) are applied. Twenty minutes after intracavernosal (IC) injection of a mixture of 60 mg. papaverine and one mg. phentolamine (regitine), 100 ml. of diluted radiographic contrast medium are infused at the rate of one or two ml./sec. while pressure is recorded, and radiographic films are exposed at the rate of one every eight to 15 seconds. PCM and PCG of the corpora cavernosa indicated the overall degree of competence of the cavernosal veno-occlusive mechanisms, and the sites of veno-occlusive incompetence; non-pharmacologic studies were unreliable in these regards. During non-pharmacologic infusion in normals, pressures rose to 40 to 45 mm. Hg, and free efflux could be visualized from multiple venous systems. After pharmacologic injection in normals, all venous channels closed, and pressures rapidly rose toward or above 200 mm. Hg, at which time the infusion was stopped. Veno-occlusive incompetence was defined angiographically when more than minimal efflux occurred during pharmacocavernosography from any venous system. The incompetence could involve the deep penile system, the deep dorsal system, or the spongiosal system, alone or in combination. Severe veno-occlusive incompetence was considered diagnostic of venogenic impotence, and was defined manometrically when IC pressures failed to exceed 100 mm. Hg during infusion of 100 ml. of fluid at 2 mm./second after IC papaverine and phentolamine injection. We believe these angiographic methods will improve the criteria against which other diagnostic and therapeutic methods can be assessed.

The efficacy of intrathrombic deposition vs. parathrombic infusion of urokinase (UK) and tissue-type plasminogen activator (t-PA) was investigated in a canine model. Gianturco coils were placed by transcatheter techniques into the iliac veins of 12 dogs. Venography obtained 48 hours later showed formation of large thrombi. After heparinization, UK (24,000-48,000 IU/ml) or t-PA (12,500-25,000 IU/ml) was spray-injected at high pressure throughout test clots every half-hour using a steel catheter with multiple side holes. Between injections, the agent was infused below the clots. The contralateral thrombi received an equivalent dose of fibrinolytic agent by continuous infusion. In six cases, plasminogen was injected into test clots prior to activator treatment. Thrombi spray-injected with either activator lysed in 64 +/- 26 minutes. Four of six thrombi treated with parathrombic urokinase infusion showed partial lysis after 133 +/- 50 minutes. After parathrombic infusion of t-PA, three clots showed complete lysis, one showed partial lysis, and two demonstrated no lysis. There was no significant difference in lysis rate between intrathrombic UK and t-PA nor did prior intrathrombic injection of plasminogen accelerate lysis. In summary, intrathrombic injection of highly concentrated UK or t-PA lysed subacute thrombi more effectively than parathrombic infusion.

Studies were designed to document the normal angiography and pressure-volume characteristics of the canine corpus cavernosum, evaluate the effects of various vasoactive agents, and characterize a veno-occlusive mechanism. In fourteen dogs, baseline cavernosography demonstrated venous drainage via six to ten tributaries arising from the crura and entering the deep penile veins. Control cavernosometry during infusion of saline at 0.33 ml./sec. led to a rise in intracavernosal pressure (ICP) from 24.9 +/- 7.9 mm. Hg to 68.4 +/- 21.1 mm. Hg. Intracavernosal injection of a number of vasodilators, including papaverine, nitroglycerin, acetylcholine, and prostaglandin E2, raised baseline ICP significantly, caused extreme elevation of pressure during saline infusion (greater than 450 mm. Hg), and narrowed or obliterated the venous lumena at the site of tunica perforation, as judged angiographically. These effects could be reversed with phenoxybenzamine or norepinephrine. Our results further support the current understanding of the canine veno-occlusive mechanism.

Pulsed-spray pharmacomechanical thrombolysis was used to treat 41 patients with 47 complete thrombotic occlusions of hemodialysis grafts (n = 29), arterial bypass grafts (n = 10), or peripheral native arteries (n = 8). The procedure involves the use of small pulses of highly concentrated urokinase, which are forcefully sprayed throughout the thrombus during systemic heparinization. Virtually complete lysis was achieved in 46 of 47 occlusions. In the 46 thrombi that lysed, mean time for completion of lysis was 63 +/- 35 min and initial partial return of flow required 26 +/- 18 min. Complications included small peripheral emboli in one treated bypass graft (which cleared promptly after further pulse-spray therapy) and bleeding in three cases (one case of hematoma in the infused field at the site of recent surgery, one case of bilateral hematomas at the femoral puncture site, and one minor delayed self-limited gastrointestinal hemorrhage). Results to date suggest that the pulsed-spray pharmacomechanical method augments the speed, consistency, safety, and cost efficacy of clinical thrombolysis. Further study is warranted.

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 arteriographic adjuncts are required: vasodilation with intracavernosal injection of a papaverine-phentolamine 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, dilatation 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.

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.