Spontaneous pulmonary hemorrhage following coronary thrombolysis

Excessive bleeding is a major concern during the administration of thrombolytic therapy. Although the great majority of these events occur at sites of vascular interruption, major gastrointestinal, retroperitoneal, genitourinary, and central nervous system hemorrhage are known to occur. We present a patient who developed spontaneous pulmonary hemorrhage during thrombolytic therapy. Lack of recognition that the lungs too may be a site of spontaneous hemorrhage during thrombolytic therapy may lead to a considerable diagnostic and therapeutic delay. Pulmonary hemorrhage should be considered in the differential diagnosis of patients who receive thrombolytic therapy in whom new roentgenographic pulmonary infiltrates present accompanied by decreases in hematocrit value.

Intramyocardial hemorrhage due to prolonged intracoronary infusion of urokinase into a totally occluded saphenous vein bypass graft

A 0.038 inch perfusion wire was used to selectively administer a 24-hr infusion of urokinase into the occluded saphenous vein bypass graft of a 69-yr-old woman. Immediately following subsequent reperfusion by balloon angioplasty, she developed a hemorrhagic myocardial infarction.

"Brain attack": an indication for thrombolysis?

OBJECTIVE

The primary objective of this article is to introduce the reader to the use of thrombolytics in the acute treatment of ischemic stroke. Theory and experimental evidence to support this approach are emphasized in addition to potential adverse effects of thrombolysis.

DATA SOURCES

A MEDLINE search was used to identify pertinent literature, including reviews.

STUDY SELECTION

Studies were selected for detailed review if they involved stroke patients and addressed possible toxicities of therapy. Any abstracts concerning ongoing clinical trials also were reviewed.

DATA EXTRACTION

Data from animal investigations using tissue plasminogen activator for the acute treatment of several models of cerebral ischemia were used to support the importance of early treatment (within six hours of symptom onset). Also, studies performed in animal models of stroke revealed that thrombolysis could be accomplished safely in acute ischemic stroke. All human studies published to data are anecdotal case reports, but point to the safety of thrombolysis if administered early. Reviews of ongoing multicenter trials are taken from published abstracts and proceedings.

DATA SYNTHESIS

Thrombolysis holds promise as a hyperacute therapy for acute stroke; however, the risk of intracerebral hemorrhage remains. Crucial to the success of this and any other therapy for acute stroke is the ability to treat patients within hours of symptom onset. Also, the importance of concomitant medications such as heparin and aspirin has not yet been addressed.

CONCLUSIONS

Pharmacists need to be knowledgeable of new treatments of stroke and the risks associated with them. As patient educators, pharmacists can contribute to public awareness by promoting the early recognition of stroke symptoms. As pharmacotherapists, pharmacists need to understand the risks and the important monitoring parameters related to thrombolysis. The results of ongoing multicenter clinical trials are awaited before making a final judgment on the usefulness of thrombolysis in acute ischemic stroke.

Proteolysis of von Willebrand factor after thrombolytic therapy in patients with acute myocardial infarction

In 20 patients with acute myocardial infarction (AMI) treated with streptokinase (SK, n = 7), recombinant single-chain tissue plasminogen activator (rt-PA, n = 7) or urokinase (UK, n = 6), the behavior of plasma von Willebrand factor (vWF) was studied before and 1.5, 3, 24, 48, and 72 hours after beginning thrombolytic therapy. vWF antigen (vWF:Ag) was high in plasma, especially after SK. The ristocetin cofactor (RiCof) activity of vWF, high before therapy, tended to decrease soon after therapy. This pattern of vWF changes was paralleled by the early loss of higher molecular weight multimers. By immunoblotting of immunopurified and reduced vWF and monoclonal antibody epitope mapping, we found that vWF was degraded after thrombolysis, especially after SK, as indicated by the higher values of two plasmin-generated fragments of 176 and 145 Kd. There were more plasmin-generated fragments in the five patients who had bleeding complications than in the remaining 15 who did not. In conclusion, quantitative and qualitative changes of vWF compatible with proteolytic degradation of the protein occur during thrombolytic therapy. Such degradation, roughly proportional to the degree of the general lytic state induced by each agent, might be a cofactor of the bleeding complications occurring in treated patients.

Thrombolytic therapy in cerebrovascular disorders

The knowledge obtained from the ongoing investigational trials of tPA for acute ischemic stroke will not only help establish the appropriate dose range and complication rates but will also further develop the clearly mandatory rapid, aggressive team approach needed to truly treat acute ischemic strokes successfully. Experimental cerebral ischemia data have pointed to the need to treat acute clinical stroke within only a few hours or less to effectively reduce stroke morbidity and mortality. Specifically, with reversible MCA occlusion models of focal cerebral ischemia (dogs and cats), the animals uniformly survive without neurological deficit if the occlusion is for less than 2 to 3 hours. Similarly in primates, MCA occlusion for 3 hours or less will lead to clinical improvement and a decrease in infarct size, with complete recovery generally associated with less than 2 hours of MCA occlusion. Therefore, it appears unlikely that ischemic brain can be salvaged if vascular occlusion persists longer than 4 to 6 hours (similar to the pathophysiology of myocardial ischemia). Further, at least one third of ischemic stroke patients reperfuse spontaneously (and obviously too late) within 48 hours of stroke onset. Several factors believed to be related to successful outcome after thrombolytic therapy are summarized in Table 16. A schematic approach to determining the response to thrombolytic agents in acute ischemic stroke is outlined in Table 17. Zivin succinctly reviews thrombolysis for stroke, both experimental and clinical, and summarizes some of the difficulties of the early clinical stroke trials with thrombolytic agents and speculates about future prospects. He believes tPA may prove valuable in the treatment of some forms of thromboembolic stroke. Its usefulness may depend in part on how quickly the drug can be initiated and the risk of side effects; factors that will require further study. The currently used doses of tPA may be too low to lyse large cerebral arterial clots and, therefore, if current trials do not show a positive treatment response, further trials with higher doses may be indicated. The implications of a potentially effective treatment for truly acute stroke are enormous: stroke will need to be considered by all (lay public through to caregivers) as a true medical emergency, analogous to MI and trauma.(ABSTRACT TRUNCATED AT 400 WORDS)

Clot-selective coronary thrombolysis with low-dose synergistic combinations of single-chain urokinase-type plasminogen activator and recombinant tissue-type plasminogen activator. The Pro-Urokinase for Myocardial Infarction Study Group

The effect of simultaneous infusions of low-dose recombinant tissue-type plasminogen activator (t-PA) and single-chain urokinase-type plasminogen activator (scu-PA, pro-urokinase) on coronary arterial thrombolysis was investigated in 23 patients treated within 6 hours (mean 2.6 +/- 1.1, range 1.2 to 5.9) of symptoms of an acute myocardial infarction. Infarct artery patency at 90 minutes was achieved in 16 (70%, 95% confidence limits of 0.47 to 0.87) of 23 patients after a 1-hour intravenous infusion of 20 and 16.3 mg of t-PA and scu-PA, respectively. At 90 minutes, the fibrinogen concentration decreased from 369 +/- 207 to 316 +/- 192 mg/dl (p = not significant), while plasminogen decreased to 69 +/- 24% (p = 0.001) and alpha-2-antiplasmin to 77 +/- 24% (p = 0.001) of pretreatment values. Although no bleeding requiring termination of drug infusion or transfusion occurred, 1 patient with cerebrovascular amyloidosis had a fatal intracerebral hemorrhage. These findings suggest that combination therapy may allow substantial reductions in total thrombolytic doses while still achieving effective fibrin-specific coronary thrombolysis.

Thrombolytic therapy soon after left heart catheterization--is it safe?

Puncture of a femoral artery for left heart catheterization is considered a relative contraindication for thrombolytic therapy for some days. We treated 9 patients with systemic thrombolysis who had undergone left heart catheterization in the previous hours. Four patients developed a large hematoma, but only 1 required transfusion. We suggest that thrombolytic therapy can be administered soon after left heart catheterization by the femoral approach, provided that continuous care can be taken over the puncture site.

Evaluation of combination thrombolytic therapy and timing of cardiac catheterization in acute myocardial infarction. Results of thrombolysis and angioplasty in myocardial infarction--phase 5 randomized trial. TAMI Study Group

Recent trials of myocardial reperfusion using single-agent thrombolytic therapy and sequential cardiac catheterization have supported a conservative approach to the patient with acute myocardial infarction. To evaluate combination thrombolytic therapy and the role of a previously untested strategy for the aggressive use of cardiac catheterization, we performed a multicenter clinical trial with a 3 x 2 factorial design in which 575 patients were randomly allocated to one of three drug regimens--tissue-type plasminogen activator (t-PA) (n = 191), urokinase (n = 190), or both (n = 194) - and one of two catheterization strategies--immediate catheterization with angioplasty for failed thrombolysis (n = 287) or deferred predischarge catheterization on days 5-10 (n = 288). Patients with contraindications to thrombolytic therapy, cardiogenic shock, or age of more than 75 years were excluded. Global left ventricular ejection fraction was well preserved and almost identical at predischarge catheterization (54%), regardless of the catheterization or thrombolytic strategy used (p = 0.98). Combination thrombolytic therapy was associated with a less complicated clinical course, most clearly documented by a lower rate of reocclusion (2%) compared with urokinase (7%) and t-PA (12%) (p = 0.04) and a lower rate of recurrent ischemia (25%) compared with urokinase (35%) and t-PA (31%). When a composite clinical end point (e.g., death, stroke, reinfarction, reocclusion, heart failure, or recurrent ischemia) was examined, combination thrombolytic therapy was associated with greater freedom from any adverse event (68%) compared with either single agent (urokinase, 55%; t-PA, 60%) (p = 0.04) and with a less complicated clinical course when the composite clinical end points were ranked according to clinical severity (p = 0.024). Early patency rates were greater with combination therapy, although predischarge patency rates after considering interventions to maintain patency were similar among drug regimens. No difference in bleeding complication rates was observed with any thrombolytic regimen. The aggressive catheterization strategy led to an overall early patency rate of 96% and a predischarge patency rate of 94% compared with a 90% predischarge patency in the conservative strategy (p = 0.065). The aggressive strategy improved regional wall motion in the infarct region (-2.16 SDs/chord) compared with deferred catheterization (-2.49 SDs/chord) (p = 0.004). More patients treated with the aggressive strategy were free from adverse outcomes (67% versus 55% in the conservative strategy, p = 0.004), and the clinical course was less complicated when the adverse outcomes were ranked according to severity (p = 0.016). No significant increase in use of blood products resulted from the aggressive strategy.(ABSTRACT TRUNCATED AT 400 WORDS)

Urokinase and AT-III concentrate treatment in inferior vena cava thrombosis associated with nephrotic syndrome

A patient with an inferior vena cava thrombosis in nephrotic syndrome was treated with heparin, AT-III concentrates and urokinase. After a few days on treatment he showed a complete resolution of the thrombosis. We suggest that this therapeutic combination may be a good approach to the treatment of thrombosis in nephrotic syndrome.

Effect of intra-arterial tissue plasminogen activator and urokinase on autologous arterial emboli in the cerebral circulation of rabbits [corrected]

We conducted a randomized, blinded controlled trial to test the efficacy of fibrinolytic therapy with tissue plasminogen activator and urokinase in the treatment of acute embolic stroke. Embolic stroke was simulated in rabbits by injecting three 0.5 x 0.5 mm fragments of autologous arterial thrombus harvested from a traumatized auricular artery. Thirty minutes after embolization the rabbits were blindly treated with tissue plasminogen activator (n = 21), urokinase (n = 20), or 0.9% saline (n = 20). At 6 hours the rabbits were sacrificed, and the cerebral vasculature was inspected for the location and number of emboli. The brain was then cut into 0.5-cm-thick coronal sections and stained with triphenyltetrazolium chloride to define areas of infarction. Treatment with either tissue plasminogen activator or urokinase significantly reduced the number of emboli present in the cerebral circulation (p less than 0.05). The area of ischemic injury was also significantly reduced (p less than 0.05) by acute fibrinolytic therapy with either tissue plasminogen activator or urokinase. However, only treatment with tissue plasminogen activator significantly reduced (p less than 0.05) the incidence of infarction. There was no evidence of intracerebral hemorrhage in any rabbit. Early fibrinolytic therapy improved outcome in this model of acute embolic stroke.

[Systemic fibrinolysis in patients with refractory unstable angina]

We tested the safety and the usefulness of intravenous fibrinolysis in 44 patients with refractory unstable angina, defined as persistence of ischemic episodes during 48-hour Holter monitoring (phase 1) despite maximal medical therapy. After fibrinolysis, recurrence of ischemia was recorded during 1 week of observation in CCU including 2 24-hour Holter monitoring at the beginning and at the end of this week (phase 2): 17 patients completed the observation period without either symptomatic or asymptomatic ischemic episodes (Group A); the remaining 27 patients continued to manifest ischemia (Group B). No bleeding complications occurred. Within a 6-month follow-up, 2 patients of Group A had recurrence of unstable angina while in Group B, 10 patients underwent CABG or PTCA for refractory angina, 6 other patients with refractory angina continued medical therapy, 1 patient had a myocardial infarction and 2 patients died (p less than 0.001). Phase 1: the duration of total ischemia (min/24 hours) was a relevant prognostic marker: higher duration correlated with adverse clinical outcome (p less than 0.01). Phase 2: in comparison with phase 1, duration of total ischemia was significantly reduced (p less than 0.001). A percent value expressing this variation was calculated for each patient: (min of ischemia in phase 2 - min of ischemia in phase 1/min of ischemia in phase 1). The variation thus obtained again gave information on the clinical outcome: the greater was the reduction, the lower was the risk of cardiac events (p less than 0.001). Our data suggest that: clinical stabilization may be obtained with the addition of fibrinolysis to conventional treatment; Holter monitoring bears prognostic information helpful in identifying patients who need further intervention.

[Thrombolysis in resuscitated patients with pulmonary embolism]

A retrospective analysis is presented of data from 17 patients with proven pulmonary embolism (10 women, 7 men, mean age 50.8 [18-76] years) who had received short-term high dosage thrombolytic therapy shortly before or after (less than 24 h) undergoing mechanical resuscitation. The mean duration of resuscitation was 76 (20-160) minutes. Two patients had already been resuscitated half an hour and one hour, respectively, before the commencement of thrombolysis. In nine other patients thrombolysis was commenced during resuscitation. Hospital mortality in the latter group was amazingly low (four of nine patients died). In contrast, out of six patients who required resuscitation shortly after the commencement of thrombolysis, not one survived. Haemorrhagic complications occurred in four out of the 17 patients, but only in two were they directly attributable to the resuscitation: one female patient developed an extensive haematoma in the sternal region, and two days after resuscitation another female patient had a haemorrhage into the capsule of the liver during thrombolytic therapy which had been continued because of leg vein thrombosis. In the light of these results it seems justifiable, even on mere clinical suspicion of pulmonary embolism, to initiate short-term high dosage thrombolytic therapy during or after resuscitation.

Acute management of intracranial hemorrhage in patients receiving thrombolytic therapy: case reports

Intracranial hemorrhage is an uncommon complication of antithrombotic therapy. We present two patients who suffered life-threatening intracranial bleeding as a complication of thrombolytic/anticoagulant treatment. Early diagnosis and treatment appear to be crucial factors for survival. We suggest an approach to perioperative management for intracranial hemorrhage resulting from antithrombotic therapy.

Femoral nerve palsy secondary to anticoagulant induced iliacus hematoma. A case report

A case of femoral neuropathy from iliac muscle hematoma occurring in a patient treated with urokinase, subcutaneous heparin and aspirin for myocardial infarction is reported. Diagnosis of this complication was suspected on the basis of clinical signs and on the fact that the patient had received anticoagulants. Computed tomography allowed direct and clear visualization of the hematoma. Anticoagulant suspension followed by an early surgical decompression seems to be the ideal treatment for this neuropathy; however, our patient died for a reinfarction after stopping heparinic administration. This may indicate that, in some patients "at risk", it is better to reduce rather than stop anticoagulant therapy.

Bleeding time and other laboratory tests to monitor the safety and efficacy of thrombolytic therapy

Widespread use of thrombolytic agents in a variety of settings has highlighted the need for measures of safety and efficacy. Previously used laboratory parameters, such as decreasing levels of fibrinogen and increasing levels of fibrin(ogen) degradation products (FDPs), have failed to correlate consistently with hemorrhagic events and have not yet been useful in predicting patients at risk for bleeding. Although the bleeding time (BT) has been considered primarily to reflect platelet function, it also reflects the interaction of platelets with vessel wall and coagulation pathways. Recently, the BT has been considered as a potential predictor of clinical bleeding during thrombolysis. The BT, as a measure of in vivo hemostatic competence, may be particularly well-suited for this application. Serial BTs during thrombolytic therapy may provide valuable information regarding safety and efficacy, but further studies are needed to confirm preliminary findings.

Urokinase administration in pediatric patients with occluded central venous catheters

The effectiveness of urokinase in declotting central venous catheters was retrospectively assessed in a pediatric population of 63 patients ranging in age from 4 days to 22 years (mean, 6.4 years). Results of treatment from 103 episodes of catheter occlusion were evaluated. Urokinase was instilled into occluded single-lumen catheters and into each lumen of double-lumen catheters, as well as into occluded implanted ports. Patency was restored to 101 of 103 occluded catheters, with no side effects observed subsequent to clearance of the catheters with the urokinase infusion. Significant cost savings were seen using urokinase to restore patency as compared to the cost of replacing the catheter. These data clearly support the use of urokinase in a pediatric population as a safe and cost-effective alternative to catheter replacement in cases of thrombotic occlusion.

Results of high dose intravenous urokinase for acute myocardial infarction

To determine the outcome of patients after treatment with high-dose intravenous urokinase (3 million U) 102 patients were prospectively evaluated in the setting of acute myocardial infarction. The first 61 patients received intravenous urokinase as a continuous infusion and the last 41 patients were treated with an initial 1.5 million U intravenous bolus. Sixty-two percent of all patients had patent infarct-related arteries by the time of immediate angiography (median time 2.2 hours), which was performed in all patients. There was no significant difference in patency rates between patients treated with or without an initial intravenous bolus. Twenty-eight (28%) patients developed clinical evidence of recurrent ischemia (death, reocclusion, emergency angioplasty, urgent bypass surgery) during hospitalization, whereas only 7 (7%) developed angiographically documented reocclusion. Of 28 patients who failed to achieve successful reperfusion at the time of immediate catheterization, rescue angioplasty was technically successful in establishing reperfusion in all but 1 patient. No significant improvement in median global left ventricular function was seen between immediate (48%) and follow-up catheterization (48%). Significant bleeding complications were unusual except in 1 patient who experienced an intracranial hemorrhage. Eight (8%) patients died during hospitalization. Therefore, the use of high-dose intravenous urokinase in patients with acute myocardial infarction is associated with a 62% patency rate, a low incidence of reocclusion and bleeding complications and a high technical success rate with rescue angioplasty at the time of immediate catheterization.(ABSTRACT TRUNCATED AT 250 WORDS)

Acceleration of thrombolysis with a high-dose transthrombus bolus technique

The rate of complication and the time necessary to achieve thrombolysis remain major disadvantages of regional thrombolytic therapy. By lacing the entire length of arterial or arterial bypass graft occlusions in the lower extremities of 49 patients with one of two different bolus doses of urokinase (mean, 52,000 International U in 35 infusions = low-dose group [28 patients]; mean, 230,000 U in 23 infusions = high-dose group [21 patients]) prior to identical continuous infusions, it was possible to demonstrate a decrease in the time needed to complete thrombolysis from 33.6 hours in the low-dose group to 10.4 hours in the high-dose group (P less than .001). The total urokinase dose necessary for successful thrombolysis was also significantly less in the high-dose group (P less than .001). The major complication rate was 22.9% in the low-dose group and 8.7% in the high-dose group, although the difference was not statistically significant. The use of urokinase and a high-dose transthrombus bolus injection technique significantly accelerates thrombolysis, decreases the total urokinase dose needed, and may lower the major complication rate.

Urokinase plus heparin versus aspirin in unstable angina and non-Q-wave myocardial infarction

The pivotal role of thrombosis in unstable angina and non-Q-wave myocardial infarction has been established recently. To assess the value and safety of thrombolytic therapy compared to conventional antithrombotic therapy (aspirin) in arresting progression in this setting to recurrent ischemic end-points, 25 patients presenting with unstable angina and an electrocardiogram showing subendocardial ischemia were randomized to receive either aspirin 325 mg daily, or urokinase 3 x 10(6) U intravenously, over 30 minutes followed by heparin. Incidence of endpoints (intractable ischemia requiring mechanical intervention, new myocardial infarction or death) was determined over 7 days. Coronary arteriography was performed at 24 to 72 hours to determine extent of coronary artery disease and morphologic severity of the culprit lesion, graded by a semiquantitative scoring system ranging from 4+ (definite thrombosis) to 0 (chronic lesion). In the first 24 hours, 7 of 13 aspirin versus 1 of 12 urokinase patients exhibited ischemia progression (p less than 0.05). By 7 days, progression to a primary ischemic endpoint occurred in 8 of 13 aspirin patients (3 myocardial infarctions and 5 intractable ischemias) versus 3 of 12 urokinase patients (2 intractable ischemias and 1 death) (p = 0.18). The apparent benefit of urokinase followed by heparin compared to conventional aspirin therapy in arresting early progression of unstable angina or non-Q-wave myocardial infarction was not associated with enhanced culprit lesion morphology (mean lesion severity score 2.7 +/- 1.5 vs 2.8 +/- 1.6 in aspirin-treated patients). Large scale, randomized trials to assess the clinical utility of urokinase for unstable angina are warranted.

A complication of prolonged urokinase infusion into a chronically occluded aortocoronary saphenous vein graft

Recanalization of a chronically occluded aortocoronary saphenous vein graft was performed, using a prolonged intracoronary infusion of urokinase followed by percutaneous transluminal coronary angioplasty (PTCA). Despite an angiographically successful result, the patient developed acute myocardial infarction, presumably secondary to distal migration of partially lysed thrombus. One week after successful angioplasty, the graft was once again proximally occluded.

Regional infusion of urokinase into occluded lower-extremity bypass grafts: long-term clinical results

The initial outcome, long-term patency rate, and rate of limb salvage were studied in patients after regional urokinase infusion for treatment of thrombosed lower-extremity grafts. Seventy-one infusions were performed in 53 patients. Complete clot lysis occurred in 75% of grafts, with establishment of antegrade blood flow in 66%. Variables that favorably influenced clot lysis and the reestablishment of antegrade blood flow through the graft were a short duration of occlusion and a suprainguinal graft position. The median duration of patency after infusion and adjunctive therapy was 162 days, with 75% limb salvage at 301 days. No statistically significant variables that influenced the length of patency were identified. These long-term patency results are inferior to the reported results in suprainguinal grafts after reoperation. They appear similar to reported results for occluded infrainguinal grafts treated with thrombectomy and patch grafting.

Continuous infusion of low-dose urokinase in the treatment of central venous catheter thrombosis in infants and children

Thrombotic occlusion is a frequent complication associated with the use of central venous catheters. The purpose of this study was to evaluate the efficacy of a continuous infusion of low-dose urokinase (200 U/kg/h) in clearing catheters that had not cleared after two bolus doses of urokinase in a pediatric oncology population. Fifty-eight incidents of catheter-related occlusions (49 Hickman-type catheters/nine implantable ports) as documented by radiographic dye study occurred in 227 pediatric oncology patients with 254 central venous catheters during a 1-year period. Fourteen of 58 catheters failed to clear after two bolus instillations of urokinase (5,000 U and 10,000 U). Thirteen catheters were treated for 24 hours with urokinase, 200 U/kg/h, and one catheter with urokinase, 100 U/kg/h for 24 hours. Twelve catheters were used for study. Coagulation studies were monitored preinfusion, 12 hours into the infusion, and postinfusion. Patency was reestablished in 11/12 catheters (92%) with a mean infusion time of 28.7 hours. No coagulation abnormalities or clinical bleeding associated with the urokinase infusion occurred. Only one patient exhibited a prolonged partial thromboplastin time (greater than 150 seconds); this was associated with a heparin effect. These data indicate that low-dose urokinase may be a safe and effective means to clear occluded central venous catheters in children.

Low dose urokinase preactivated natural prourokinase for thrombolysis in acute myocardial infarction

By inducing minimal free-fibrinolytic activity with low dose urokinase, the lag phase of prourokinase can be overcome, and the rate of thrombolysis with this substance can be strongly enhanced. The thrombolytic potency of a combination of 250,000 IU of urokinase and 2 doses of prourokinase (4.5 or 6.5 megaunits) was evaluated in an open-label, nonrandomized dose-finding study. Thirty-one patients participated. With 4.5 megaunits of prourokinase (group 1, 15 patients) patency was demonstrated angiographically at 60 minutes in 33% while with 6.5 megaunits (group II, 16 patients) 75% patency was achieved (p less than 0.01). A second angiogram recorded 24 to 36 hours after thrombolysis revealed reocclusion in 60 versus 8% of primarily patent coronary arteries (p less than 0.05). Hemostatic monitoring in both groups revealed only slight to moderate consumption of fibrinogen (-9 vs -13%), plasminogen (-29 vs -34%) and alpha 2-antiplasmin (-59 vs -63%), and an increase in D-dimers, the split products of cross-linked fibrin, to a maximum of 1.008 +/- 1.211 vs 0.547 +/- 0.684 micrograms/liter. None of these differences was significant. Bleeding complications were more frequently observed in group II (13 vs 37%) (difference not significant), but were mild and related to puncture sites, except in 1 patient with mild oozing from the gum. No major hemorrhage was observed. These results suggest that low dose urokinase preactivation enhances the thrombolytic potency of prourokinase, without affecting its high fibrin specificity. Compared to previous studies using only prourokinase, low dose urokinase preactivation reduces by 50% the prourokinase dose as required for effective thrombolysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Low-dose fibrinolytic therapy for recent lower extremity thromboembolism

Low-dose catheter-directed fibrinolytic therapy (LDCF) using streptokinase (35) and urokinase (7) was performed on 42 separate occasions in 36 patients for recent lower extremity thromboembolic occlusion. Twenty-seven grafts and 15 native arteries were treated. Causes of occlusion were known in 32 instances: native artery proximal or distal occlusive disease or both (18 vessels); bypass graft stenosis (6); aneurysm (2); embolus (4); and postangiography thrombosis (2). Twenty-nine infusions were technically successful, and patients were clinically improved by 26 of the treatments. Twelve patients had unsuccessful infusions and six underwent subsequent amputation. In all patients, infusions longer than 12 hours resulted in prolonged thrombin times and lowered plasma fibrinogen concentrations; one infusion was discontinued due to a low fibrinogen concentration. Complications occurred on 17 occasions and included hemorrhage (6), distal embolization (3), compartment syndrome (1), retrograde thrombosis during infusion (5), hypotension (1), and systemic fibrinogenolysis (1). The cumulative success rate was 44% +/- 9% at 24 months. Late rethrombosis (five instances) was more common in patients who had inflow or outflow structural lesions not corrected following successful fibrinolysis. LDCF is a useful alternative to other methods of treatment for recent onset lower extremity thromboembolic occlusion. Structural vascular lesions uncovered by successful infusion should be corrected immediately after infusion to ensure long-term patency.

Bleeding after thrombolysis in acute myocardial infarction

232 consecutive patients with acute myocardial infarction were treated either with 2 x 10(6) IU urokinase as an intravenous bolus injection, or 250,000 IU streptokinase intracoronary, or 60 mg recombinant tissue-type plasminogen activator (rt-PA) over 90 min. All patients enrolled had chest pain for more than 30 min and less than 3 h before admission and a typical electrocardiogram. Contra-indications to thrombolytic treatment were absent. All bleeding complications occurring within 24 h after admission were assumed to be due to thrombolytic therapy. Bleeding complications occurred in 14 patients (6.5%). Only seven patients received a blood transfusion (3%). No correlation was evident between previous hypertension, diabetes mellitus, smoking, sex, age, fibrinogen level before and 24 h after thrombolytic therapy and bleeding complications. The risk of bleeding was not significantly different between the different thrombolytic regimens despite marked differences in the fall of the fibrinogen level. The decrease of fibrinogen following thrombolytic therapy did not influence the patency rate of the infarct vessel. Thrombolytic therapy in acute myocardial infarction is a safe treatment even among patients advanced in years and with medically controlled hypertension and diabetes mellitus, irrespective of the kind of thrombolytic treatment.

Endoarterial treatment of acute ischemia of the limbs with urokinase. Italian Cooperative Study "Bologna"

Authors report the results of the treatment of acute ischemia of the limbs with urokinase in patients included in a polycentric study group called "Bologna". A total of 111 patients affected with acute ischemias of the limbs caused by arterial or graft thromboses were treated with intra-arterial urokinase with a loading dose of 200,000 U.I., followed by 75,000 I.U./hour maintenance dose for 72 hours at the most. With this treatment 83.5% of clinically positive results was obtained. Complications and angiographic results are discussed.

Thrombolytic therapy in acute arterial thrombosis

The courses of 17 patients who underwent 20 separate attempts at thrombolysis for acute arterial thrombosis are reviewed to clarify the safety and efficacy of this therapy. Seventeen of 20 thrombolyses were angiographically successful. Patients who had correctable lesions identified and reconstructive procedures performed tended to do better than those who did not, and patients who had successful thrombolysis tended to have fewer and less radical amputations. Complications can be reduced by careful, close monitoring of patients undergoing therapy.

[Use of urokinase in acute myocardial infarction]

Clinical course of the disease and the formation of the necrotic focus (as evidenced by precordial mapping from 35 ECG leads) were assessed in 88 patients with acute myocardial infarction, treated with 1,000,000 IU urokinase, in comparison to 41 untreated control patients. Thrombolytic therapy, started within the first 6 hours of myocardial infarction, was associated with a better clinical course of the disease. Urokinase administration after 6 hours from the onset of the symptoms produced no clinical improvement, did not limit the necrotic focus and failed to reduce mortality, as compared to the controls. The assessment of the efficiency of thrombolytic treatment demonstrated an at least 30% increment of venous flow in 45% of patients. Intravenous urokinase administration was accompanied by an activation of blood fibrinolytic system, and there was a tendency to fibrinolysis depression on the day following the administration.

Cost-effectiveness of intra-arterial thrombolytic therapy

We reviewed the clinical course of 23 patients who received 24 intra-arterial infusions of either streptokinase or urokinase to treat 14 arteries and ten arterial grafts that were occluded due to primary thrombosis (22) or artery-artery embolism (two). Time from symptom onset to treatment was one to 28 days (mean, 11 days). Five infusions (21%) were completely successful since symptoms were eliminated without subsequent operation. Seven infusions (29%) were partially successful since thrombolysis aided, limited, or postponed subsequent surgery. Six infusions (25%) were failures since thrombolysis or clinical improvement did not occur and surgery was required. Six infusions (25%) were associated with thrombolytic complications that required urgent operation (less severe complications occurred in an additional 17% of cases [4/24]). Of the 19 patients without complete success after thrombolytic therapy, 16 underwent surgery during the same admission, two were not operable due to distal disease, and one declined operation. Of the 16 operations, 15 (94%) were successful in restoring graft or artery patency and achieving limb salvage, whereas one failed. In the 12 patients with failure or major complications of thrombolytic treatment, all had successful surgical outcome without morbidity. The actual mean cost of thrombolytic treatment was $8200 per patient and was comparable with the actual mean cost of subsequent surgical treatment in the 16 patients who required operation ($8900 per patient). The effective cost of thrombolytic and surgical treatment was calculated by dividing the actual costs by the proportion of successful cases. The effective cost of thrombolytic therapy per complete success was $39,200 and per complete or partial success was $16,500. This was significantly more than the effective cost of $9400 per complete success of surgical therapy.

Embolization of cardiac mural thrombus: complication of intraarterial fibrinolysis

A case of embolization of cardiac mural thrombus during intraarterial infusion of urokinase is reported. The mechanism of embolization is believed to be secondary to a systemic fibrinolytic effect induced by urokinase.

Efficacy of intravenous prourokinase and a combination of prourokinase and urokinase in acute myocardial infarction

Fifty-four patients with Q-wave acute myocardial infarction (AMI) were treated with heparin combined with intravenous single-chain urokinase-type plasminogen activator (prourokinase). To determine the optimal treatment regimen, prourokinase was applied in 3 different ways: group I received a bolus of 7.5 mg and a subsequent infusion of 40.5 mg over 60 minutes. Patency of the infarct artery was observed in 7 patients (50%) at the end of the infusion time. One hour after the end of the infusion the fibrinogen level had decreased to 87 +/- 12% of the preinfusion level; the plasminogen and alpha-2 antiplasmin levels to 61 +/- 13% and 59 +/- 34%, respectively. In group II prourokinase was administered as a 7.5 mg bolus followed by 66.5 mg over 60 minutes. Eleven patients (55%) had patent infarct-related coronary arteries and fibrinogen, plasminogen and alpha-2 antiplasmin levels had decreased to 58 +/- 29%, 38 +/- 18% and 21 +/- 14%, respectively. Group III was treated with a bolus of 3.7 mg prourokinase and 250,000 IU urokinase followed by 44.3 mg prourokinase, resulting in a patency rate of 65% (13 patients). Fibrinogen, plasminogen and alpha-2 antiplasmin levels decreased to 76 +/- 15%, 67 +/- 15% and 47 +/- 29%, respectively. Fibrin-specific thrombolysis can be achieved with glycosylated prourokinase. At higher dosages considerable systemic activation of the fibrinolytic system with little enhancement of the observed therapeutic effect occurred. The combination of prourokinase and urokinase yielded a higher patency rate than either dosage of prourokinase alone, although the difference was not statistically significant in this pilot trial.

Local intra-arterial fibrinolytic therapy in acute carotid territory stroke. A pilot study

The possibility that intra-arterial local infusion of fibrinolytic agents may achieve recanalization of previously occluded carotid territory arteries in acute stroke was tested in a prospective angiography-based open pilot study at two centers. Fifteen of 20 patients with acute symptoms (mean treatment-onset interval 7.6 hours) demonstrated complete recanalization; 10 of the 15 patients exhibited clinical improvement of varying degree by the time of hospital discharge. Four of the 20 patients suffered hemorrhagic transformation of the infarcted territory without clinical deterioration or demise. Because of the study format and the limited number of patients, dose responses for recanalization and risk relations were not established. We conclude that local intra-arterial fibrinolytic therapy may lead to cerebral arterial recanalization in acute carotid territory thrombotic stroke. The particular implications and limitations of this approach are discussed.

Comparison of cost effectiveness of streptokinase and urokinase in the treatment of deep vein thrombosis

This study examines the comparative efficacy, safety, and cost associated with treatment of deep vein thrombosis with streptokinase or urokinase. Sixty patients were analyzed retrospectively, 30 treated with streptokinase and 30 treated with urokinase. Statistically significant greater fibrinogenolysis was noted when streptokinase was used to treat patients with deep venous thrombosis (p = 0.01). The mean decrease in fibrinogen from preinfusion value was 83% in the streptokinase treated group and 61% in the urokinase treated group. Five of 30 (17%) of the streptokinase treated patients experienced major complications. No major complications were seen in the urokinase treated group (p = 0.019). Cost analysis demonstrates that therapy with urokinase was $11.40 per patient more than streptokinase. If complications are not included in the cost analysis, then urokinase becomes only $650 per patient more expensive than streptokinase therapy. These data support that deep vein thrombosis treatment with urokinase is effective, safer and more cost efficient when compared to streptokinase.

Local thrombolysis in peripheral arteries and bypass grafts

Sixty-two patients hospitalized for recent angiographically documented arterial occlusion in the legs (46 femoropopliteal arteries and 16 grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a No. 4F or No. 5F catheter. This therapy combined a continuous urokinase (UK) infusion of 1000 U/kg/hr and a lysyl plasminogen (LYS-PLG) infusion of 15 mukat every 30 minutes. Angiographically confirmed lysis was obtained in 77% of the cases. Five percent of the patients had major and 8% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK and LYS-PLG is as effective as streptokinase but produces lower systemic fibrinolysis. However, local fibrinolysis remains a potentially hazardous procedure (10% suffered major complications) and must only be applied to patients with severe ischemia and little or no possibility of surgical intervention.

Randomized double-blind trial of intracoronary urokinase for acute myocardial infarction: multicenter study

The efficacy of intracoronary urokinase (UK) in an acute myocardial infarction has not been firmly established in a randomized fashion. Two hundred and ten patients were randomized to UK therapy (107 patients) and placebo (103 patients). Successful recanalization was achieved in 74% of the UK group vs 17% in the placebo group (p less than 0.01). The success rate was dose dependent up to 960,000 I.U. Clinical course was favorable and left ventricular enddiastolic pressure was reduced significantly in the UK group compared with the placebo group (p less than 0.05). Ejection fraction one month after the study was better in the reopened group than in the occluded group. Thus, early administration of UK can establish coronary reflow in a high proportion of patients and appears to favor the clinical course.

Appraisal of various thrombolytic agents in the treatment of acute myocardial infarction

The immediate therapeutic objective after the onset of symptoms of an evolving myocardial infarction is to stop the process from progressing. Evidence has accumulated that this can be accomplished by the early dissolution of the clot within an acutely thrombosed artery, resulting in reperfusion of the ischemic area. There are five clot-dissolving agents currently being evaluated by intravenous administration for their ability to dissolve coronary thrombi and to produce clinical benefit; all are plasminogen activators and each has distinctive properties. Streptokinase, because it has been the agent most extensively studied and its clinical benefits have been established, now serves as a standard for comparison with the others (anisoylated plasminogen-streptokinase activator complex, urokinase, recombinant tissue plasminogen activator, and recombinant pro-urokinase). It is apparent that each of the agents has advantages and disadvantages and that none has established its superiority over the others as of yet.

Thrombolysis in the treatment of peripheral arterial vascular occlusions

The efficacy of thrombolytic agents in the management of peripheral arterial disease remains unclear. We reviewed our experience with 64 consecutive episodes of limb-threatening graft or native vessel occlusions. The overall success rate was 59%, with a major complication/mortality rate of 28%. Thrombolytic therapy in patients with occluded vascular grafts required identification of a causative lesion and subsequent adjunctive management with percutaneous transluminal angioplasty or surgery for sustained patency (64%). In contrast, approximately 70% of native vessel occlusions maintained patency whether a causative lesion was identified and corrected or not. Patients who failed thrombolytic therapy had a worse prognosis overall, with 38% undergoing primary amputation, although patients with reconstructable occlusions still had a 64% salvage rate at six months. The review demonstrated that thrombolytic therapy continues to be a useful adjunct in treating the patient with peripheral vascular occlusion, although a significant risk of major complications persists. Patients with graft occlusions successfully treated with thrombolysis require correction of any precipitating lesions for long-term limb salvage, while careful management of patients failing thrombolysis can still achieve significant limb salvage in selected cases.