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K Valji

Publications and source records attributed to K Valji.

At least 37 records · Page 2Linked to original sources
PubMed1993

Pulse-spray pharmacomechanical thrombolysis for treatment of thrombosed dialysis access grafts.

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.

Angioplasty, Balloon↗
PubMed1993

Effects of intrathrombic administration of prostaglandin E1 during pulse-spray thrombolysis with tissue-type plasminogen activator in experimental thrombosis.

The effects of intrathrombic and intravenous injection of prostaglandin E1 (PGE1) during pulse-spray thrombolysis were studied in a rabbit model. Thrombi were produced in the inferior vena cava of 46 rabbits by means of vessel wall injury and placement of steel coils. At 2 days, pulse-spray thrombolysis was performed by using a catheter with multiple side holes spanning the clot. A control group received injections of saline. In all other rabbits, 3 mg of tissue-type plasminogen activator (tPA) was injected into the thrombus over 1 hour, and 500 U of heparin was intravenously administered. PGE1 was administered either intravenously (50 micrograms) or directly into the thrombus (10, 25, or 50 micrograms) in four groups. After treatment, the rabbits were killed and the residual clot was weighed. The relationship between clot length and volume measured on angiograms and clot weight was assessed in 13 additional untreated rabbits. Linear regression analysis was used to estimate the initial clot weight on the basis of measured clot length in treated animals. The extent of clot lysis was significantly greater with injection of tPA and 10-, 25-, or 50-micrograms PGE1 directly into the thrombous than with administration of tPA alone.

Alprostadil↗
PubMed1993

Occluded peripheral arteries and bypass grafts: lytic stagnation as an end point for pulse-spray pharmacomechanical thrombolysis.

Angiographic demonstration of luminal narrowing during pulse-spray pharmacomechanical thrombolysis (PSPMT) may reflect residual lysable clot, organized thrombus, platelet-rich clot, atherosclerosis, neointimal hyperplasia, or functional narrowing. The authors evaluated the efficacy and safety of lytic stagnation (initial rapid lysis followed by insubstantial further lysis with additional treatment) as an end point for PSPMT. Lytic stagnation was evaluated with serial angiography in 16 arterial and five bypass graft occlusions. Substantial lysis occurred after administration of mean doses of 512,000 units +/- 182,000 of urokinase or 5.3 mg +/- 2.0 of tissue-type plasminogen activator. Additional treatment with either of those agents produced minimal or no further change in the appearance of residual disease. Recanalization was successful in all patients after angioplasty. Distal emboli were noted in four cases, in three of which angioplasty of large intraluminal filling defects had been performed. The authors conclude that lytic stagnation is a reliable and safe end point for PSPMT in the absence of large intraluminal filling defects.

Adult↗
PubMed1993

Diagnosis of arteriogenic impotence: efficacy of duplex sonography as a screening tool.

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.

Adolescent↗
PubMed1992

Efficacy of adjunctive intrathrombic heparin with pulse spray thrombolysis in rabbit inferior vena cava thrombosis.

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.

Animals↗
PubMed1992

Gastrointestinal hemorrhage in AIDS: arteriographic diagnosis and transcatheter treatment.

The usefulness of arteriography and transcatheter treatment was studied in nine patients with gastrointestinal hemorrhage and acquired immunodeficiency syndrome (AIDS). Selective arteriography was performed in all patients; transcatheter treatment was performed by means of embolotherapy or selective vasopressin infusion. Medical records were reviewed to determine the cause of hemorrhage and clinical outcome. Arteriography enabled identification of the site of hemorrhage in seven patients. Hemorrhage was caused by Kaposi sarcoma (n = 2), cytomegalovirus colitis (n = 1), lymphoma (n = 2), or unknown causes (n = 4). Neovascularity and dense parenchymal stain were present in patients with Kaposi sarcoma. Transcatheter treatment consisted of embolization (n = 3), vasopressin infusion (n = 2), or both (n = 1). Hemorrhage was controlled in six cases in which transcatheter treatment was administered. Complications included thrombosis of the femoral artery in a 7-month-old infant and formation of a pseudoaneurysm of the femoral artery, which was treated successfully with ultrasound-guided compression. In patients with AIDS and profuse gastrointestinal hemorrhage, arteriography often enables identification of a specific site of hemorrhage, which can be stopped with transcatheter treatment.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Pharmacomechanical thrombolysis and angioplasty in the management of clotted hemodialysis grafts: early and late clinical results.

The results of pharmacomechanical thrombolysis and angioplasty of 121 thrombosed hemodialysis grafts were reviewed. The initial pharmacomechanical method (used in 65 cases) employed clot maceration with hook-shaped catheters and clot lacing with highly concentrated urokinase. The current technique (used in 56 cases) consisted of pulsed-spray injection of urokinase into the clot. All fully treated grafts (117 cases) underwent complete or near-complete thrombolysis, and 93% remained patent after 1 day. Mean time for pulsed-spray lysis was 46 minutes +/- 21. One patient (less than 1%) had gastrointestinal bleeding and received a transfusion; minor complications occurred in 3% of patients. Primary and secondary graft patency rates for both methods at 1 year were 26% and 51%, respectively. While graft age and results of angioplasty did not influence future graft patency, shorter intervals between graft thromboses was predictive of earlier subsequent graft failure. Results suggest that pharmacomechanical thrombolysis and angioplasty provide rapid, consistent, and safe recanalization of clotted hemodialysis grafts and represent a promising additional therapeutic approach to long-term graft management.

Angioplasty, Balloon↗
PubMed1991

Pulsed-spray thrombolysis of arterial and bypass graft occlusions.

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.

Angioplasty, Balloon↗
PubMed1989

Pulsed-spray pharmacomechanical thrombolysis: preliminary clinical results.

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.

Arteriovenous Shunt, Surgical↗
PubMed1988

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 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.

Angioplasty, Balloon↗
PubMed1987

The veno-occlusive mechanism of the canine corpus cavernosum: angiographic and pharmacologic studies.

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.

Animals↗
PubMed1987

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.

Adult↗
PubMed1987

Penile pharmacocavernosography and cavernosometry in the evaluation of impotence.

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.

Adult↗
PubMed1987

Fibrinolysis with intrathrombic injection of urokinase and tissue-type plasminogen activator. Results in a new model of subacute venous thrombosis.

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.

Animals↗
PubMedDate not supplied

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.

Adolescent↗
PubMedDate not supplied

Transcatheter manipulation of asymmetrically opened titanium Greenfield filters.

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.

Catheterization, Central Venous↗