Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.4.21.73 (urokinase-type plasminogen activator)
10,685 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Conventional balloon angioplasty in the presence of intracoronary thrombus is associated with an elevated risk for acute myocardial infarction, emergency bypass surgery, and death. The purpose of this study was to assess the safety and efficacy of a new technique to treat thrombus-containing stenoses consisting of the local delivery of urokinase directly to the site of intraluminal clot with hydrogel-coated balloons. Ninety-five patients with angiographically apparent intracoronary thrombus were treated with urokinase-coated hydrogel balloons either prior to (n = 74) or following (n = 21) conventional balloon angioplasty. Clinical diagnoses for the study group included acute myocardial infarction in 50 patients, postinfarction angina in 23 patients, and unstable angina in 22 patients. All hydrogel balloons were initially coated with urokinase by immersing the inflated balloon in a concentrated Abbokinase solution (50,000 units/ml) for 60 s. All patients were subsequently treated with drug-coated balloons using a balloon:artery ratio of 1:1, a mean of 2.2 +/- 1.2 inflations, and a mean total inflation time of 7.5 +/- 4.9 min. Use of urokinase-coated balloons resulted in angiographic disappearance of intracoronary thrombus in 78 patients, improvement in 14, and no change in the remaining 3 patients. Following hydrogel balloon use for the entire 95 patients, TIMI flow increased from 1.4 +/- 1.2 to 2.9 +/- 0.4, minimal lumen diameter increased from 0.4 +/- 0.4 to 2.0 +/- 0.6 mm, and thrombus score decreased from 2.0 +/- 0.9 to 0.2 +/- 0.6 (all P < 0.01). Procedural and early in-hospital complications were noted in 7 of the 95 patients (7.4%) and included abrupt closure in 3 patients, distal embolization in 1 patient, no reflow in 1 patient, sidebranch occlusion in 1 patient, and late closure in 1 patient. Two of the 3 patients with abrupt closure and the single patient with late closure required intracoronary stenting to maintain vessel patency. Two of these 7 patients sustained small myocardial infarctions, although no patient required emergency bypass surgery or experienced a procedural death. Late clinical follow-up (mean = 8.3 +/- 6.6 months; range = 2 wk to 29 mo) demonstrated adverse recurrent events in 29 of the 95 patients (30.5%), including death (n = 5), myocardial infarction (n = 2), and recurrence of angina (n = 22). The results of this study suggest that intracoronary thrombolysis can be safely and rapidly achieved by using limited quantities of urokinase delivered directly to the site of intraluminal clot with hydrogel balloons. Use of this technique may result in improved acute outcomes in comparison with conventional techniques currently being used to treat thrombus-containing stenoses.
...
PMID:Site-specific intracoronary thrombolysis with urokinase-coated hydrogel balloons: acute and follow-up studies in 95 patients. 921 22

Percutaneous treatment of thrombotic stenoses or total occlusions in aged saphenous vein bypass grafts is associated with a significant incidence of complications primarily related to distal embolization. The purpose of this study was to assess the efficacy of local urokinase delivery with the Dispatch catheter prior to balloon angioplasty and/or intragraft stent placement as a new technique of vein graft revascularization. Local urokinase delivery with the Dispatch catheter was performed in 15 saphenous vein grafts (mean age = 11.7 +/- 2.5 yr) in 13 patients with unstable or postinfarction angina. The target lesion was a total occlusion in 5 of the procedures and a severe vein graft stenosis in the remaining 10. In all cases, urokinase was administered directly to the site of the stenosis/occlusion via the Dispatch catheter at 0.5 cc/min and at a concentration of 30,000 units/cc. The mean urokinase infusion time for the 15 procedures was 33 +/- 10 min (range = 10-60 min) and the mean urokinase dose was 495,000 +/- 158,000 units (range = 150,000-900,000 units). Following Dispatch therapy, mean minimal lumen diameter increased from 0.34 +/- 0.32 to 1.81 +/- 0.78 mm (P < 0.01), mean TIMI flow increased from 1.9 +/- 1.4 to 2.8 +/- 0.8 (P < 0.06), and mean thrombus score was reduced from 2.3 +/- 0.6 to 0.3 +/- 0.8 (P < 0.01). Mild no reflow was noted in two cases, although no patient demonstrated angiographic evidence of gross distal embolization. One of the patients with no reflow also demonstrated a small increase in cardiac enzymes. Subsequent balloon angioplasty/stent placement was successful in 14 of the 15 procedures (93% success rate). This preliminary report suggests that pretreatment of thrombotic saphenous vein graft stenoses with local urokinase delivery via the Dispatch catheter may decrease intragraft thrombus and possibly decrease the incidence of vascular complications associated with percutaneous intervention. This technique may allow for recanalization of totally occluded vein grafts with large clot burdens by using significantly less urokinase and shorter drug administration times than conventional infusion protocols.
...
PMID:Treatment of thrombotic saphenous vein bypass grafts using local urokinase infusion therapy with the Dispatch catheter. 921 24

A total of 147 stents were implanted (in overlapping manner in 76% of vessels) in a single coronary artery in 59 patients (60 vessels, 97 lesions, 2.45 stents/vessel) over a period of 18 mo using high pressure stent deployment without ultrasound guidance. The indications for stenting were suboptimal percutaneous transluminal coronary angioplasty (PTCA) result (45%), primary prevention of restenosis (44%), acute closure (10%), and restenosis after plain balloon angioplasty (1%). One patient required emergency coronary artery bypass grafting (CABG) (extensive dissection), and one required early intervention with plain balloon angioplasty and intracoronary urokinase for stent thrombosis. There were no deaths. Thirteen patients had recurrence of angina within 6 mo and angiograms were performed in all. These showed intrastent restenosis in nine (all had successful repeat plain balloon angioplasty), development of new disease in other vessels along with restenosis close to the stent in the target vessel in one (underwent elective CABG) and normal angiograms with widely patent stents in three. Forty-five patients (77%) remained free of recurrent angina and 25 of these had follow-up angiograms (56%) at a mean of 172 days, two showing restenosis. Thus, the restenosis rate per patient in the symptomatic group (angiographic follow-up in 100%) was 77% and in the asymptomatic group (angiographic follow-up in 56%) was 8%. The restenosis rate in the subgroup with bailout stenting (n = 6) was 20% (angiographic follow-up in 83%). The overall restenosis rate per patient was 32% (overall angiographic follow-up in 66%). During the 6-mo follow-up period, one patient underwent elective CABG (1.7%), one sustained a non-Q myocardial infarction (1.7%), nine had repeat PTCA to the target vessel (15.5%), and there were no deaths. The event-free survival rate was 77%. Multiple stent implantation aided by high pressure stent deployment without ultrasound guidance and with adjunctive optimal antiplatelet therapy without oral anticoagulation seems to be a useful and effective revascularisation strategy to deal with long lesions and acute dissections with a high procedural success rate. The restenosis rate is acceptable and is not appreciably high as reported in previous studies from the "warfarin era."
...
PMID:Multiple stent implantation in single coronary arteries: acute results and six-month angiographic follow-up. 932

This study was conducted in an attempt to clarify whether preinfarction angina has an ischemic preconditioning effect. The subjects of this study were Killip class I patients who had suffered a first acute myocardial infarction (MI) as a result of total occlusion of the proximal left anterior descending coronary artery without development of collateral vessels and multivessel coronary artery disease. All subjects achieved successful reperfusion [thrombolysis in myocardial infarction (TIMI) flow grade 3] through intracoronary thrombolysis with single-chain urokinase-type plasminogen activator (SCU-PA). Subsequently, they received the same drug therapy and remained free of reocclusion. The patients were divided into those who experienced a new onset of prodromal angina within 24 h before the onset of acute MI [PA(+) group] and those who had a sudden onset of acute MI without the preceding angina [PA(-) group]. They were further divided according to the time interval from the onset of acute MI to reperfusion (within 1 h, 1-2 h, 2-3 h, 3-4 h, and 4-7 h). In addition, the left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume index (LVEDVI), and the amount of creatine kinase (CK) released (sigma CK) were compared in these 2 groups at reperfusion time. The results of this study showed that sigma CK was significantly lower in the PA(+) group than in the PA(-) group (1,850 mIU vs 3,583 mIU) when reperfusion was induced within 1 h after the onset of acute MI. When reperfusion was induced 1-2 h after the onset of acute MI, sigma CK tended to be lower in the PA(+) group than in the PA(-) group (3,677 mIU vs 5,261 mIU). Once the time to reperfusion exceeded 2 h, there was no significant difference in sigma CK between these 2 groups. On the other hand, there were no significant differences in LVEF and LVEDVI between these 2 groups at any reperfusion time. In conclusion, preinfarction angina had a preconditioning effect (reduction in sigma CK), but this effect was lost once the time interval from the onset of acute MI to reperfusion exceeded 2 h.
...
PMID:Relationship between preinfarction angina and time interval to reperfusion with thrombolytic therapy in acute myocardial infarction. 938 66

Despite progress in the invasive revascularization procedures and even though conventional antianginal treatment has improved the quality of life in patients with symptomatic coronary artery disease considerably, an increasing number of patients suffers from end-stage coronary artery disease and refractory angina pectoris. For these refractory patients long-term intermittent urokinase therapy was developed as an antithrombotic intervention, which is based on its capacity to enhance thrombolysis and blood rheology, and may possibly lead to plaque regression. The coronary syndrome of refractory angina pectoris is characterized by a mismatch of severe coronary insufficiency and a relatively large amount of viable myocardium as indicated by an only moderately impaired left ventricular function. Prior to initiation of long-term intermittent urokinase therapy all potential measures to improve myocardial perfusion have to be considered in each patient. These supportive measures include rigorous reduction of LDL-cholesterol, which has proven antiischemic properties due to an improved endothelial function of epicardial conductance vessels possibly resulting in an antianginal effect. Apart from the proven antiischemic properties of long-term intermittent urokinase therapy in patients with refractory angina pectoris, objective signs of ischemic myocardial heart failure improve. Follow-up studies demonstrated a significant increase of left ventricular ejection fraction as evaluated with multi-gated blood pool analysis. Furthermore, left ventricular diastolic function normalized after a treatment period of 12 weeks. As the clinical effects last well beyond the actual treatment period and as they are accompanied by a remarkable increase in the quality of life, a complex approach as this one is justified in this highly symptomatic patient group.
...
PMID:[Conservative therapeutic approaches in terminal coronary heart disease. Chronic intermittent urokinase therapy]. 944 Nov 57

The long-term patency of saphenous vein graft (SVG) lesions after intervention has been shown to be improved with new interventional techniques such as stents. Long-term outcome of patients undergoing successful angioplasty of totally occluded old SVGs with new devices is unknown. From July 1994 to June 1996, 19 patients with totally occluded old SVGs had successful angioplasty with new interventional techniques. Mean SVG age was 123 +/- 8 mo. Thrombolysis in myocardial infarction trial (TIMI) flow was 0 in all target lesions. TIMI 2 or 3 flow was restored after angioplasty in all patients. Intracoronary urokinase, transluminal extractional atherectomy, and stenting were used in 14, 12, and 6 patients, respectively. There was one in-hospital death due to ongoing myocardial infarction, no recurrent infarction, and no repeat angioplasty or bypass surgery in the hospital. At follow-up of 21 +/- 1 mo, there was one sudden death and one myocardial infarction. Five patients had repeat coronary bypass surgery, and 4 had repeat angioplasty. Thirteen patients remained asymptomatic, and 4 had angina. The long-term outcome of patients who had successful reopening of occluded old SVGs is encouraging in this small sample.
...
PMID:Angioplasty of totally occluded old vein grafts with new interventional techniques: a long-term follow-up study. 963 35

Antiischemic effectiveness of long-term urokinase therapy and isovolemic hemodilution therapy has been reported in patients with symptomatic coronary artery disease, but both interventions have never been compared. In patients with refractory angina pectoris and end-stage coronary artery disease (clinical functional class III), isovolemic hemodilution (n = 9) (hydroxyethyl starch solution 6%, 1-2 times/week), and urokinase therapy (n = 11) (500,000 U urokinase per i.v. injection, 3 times a week) were performed over a period of 12 weeks, each additionally to maximal conventional treatment. Apart from the assessment of clinical symptoms and rheologic parameters, invasive hemodynamic measurements were carried out at rest and during exercise testing before and after treatment. After treatment with urokinase, patients showed a significant reduction of clinical symptoms (from 19.8 +/- 6.5 to 5.0 +/- 4.3 anginal events/week, p < 0.001), fibrinogen (from 410 +/- 88 to 238 +/- 40 mg/dl, p < 0.001), plasma viscosity (from 1.45 +/- 0.10 to 1.33 +/- 0.03 mPa x s-1, p < 0.01), and no changes of hematocrit (from 0.45 +/- 0.02 to 0.45 +/- 0.02) and whole blood viscosity (from 4.7 +/- 0.5 to 4.4 +/- 0.7 mPa x s-1); however, hemodilution resulted in a decrease of hematocrit (from 0.46 +/- 0.01 to 0.39 +/- 0.01, p < 0.001) and whole blood viscosity (from 4.7 +/- 0.5 to 4.0 +/- 0.3 mPa x s-1, p < 0.001) and no changes of initially comparable levels of clinical symptoms, fibrinogen, and plasma viscosity. Hemodynamic parameters at rest improved after urokinase therapy with a reduction of pulmonary capillary wedge pressure (from 9.1 +/- 5.1 to 5.5 +/- 2.8 mmHg, p < 0.05) at comparable levels of systemic vascular resistance (from 1510 +/- 340 to 1420 +/- 510 dyn x s x cm-5). Hemodilution did not result in any significant hemodynamic changes. Apart from clinical symptoms, long-term intermittent urokinase therapy reduces pulmonary capillary wedge pressure at rest. This may reflect an improved diastolic function due to a rheological enhancement of myocardial perfusion at the level of the coronary microcirculation. Isovolemic hemodilution seems to be of no benefit.
...
PMID:Long-term Urokinase Therapy and Isovolemic Hemodilution: A Clinical and Hemodynamic Comparison in Patients with Refractory Angina Pectoris. 982 8

Antithrombotic therapy is a basic part in the treatment of acute as well as chronic coronary syndromes. The rationale is an enhanced platelet activity with predomination of procoagulatory mechanisms in coronary artery disease. The current status of antiplatelet drugs, anticoagulation, and chronic thrombolysis used in the treatment of chronic coronary syndromes is discussed. It is concluded that low-dose aspirin is the current drug of choice for long term oral treatment in patients with stable chronic coronary artery disease. In contrast, oral anticoagulation with coumadin should be considered in patients with higher risk for atrial or ventricular thrombosis. The impact of long-term intermittent urokinase therapy in patients with end-stage coronary artery disease and refractory angina pectoris leads to a marked improvement of clinical symptoms. Oral blockade of platelet membrane glycoprotein IIb/IIIa receptor and clinical trials regarding antiischemic effects of low-molecular weight heparins in chronic coronary syndromes are expected for the future.
...
PMID:[Antithrombotic therapy in chronic coronary syndromes--value of thrombocyte aggregation inhibition, anticoagulation and chronic thrombolysis]. 982 73

Patients with refractory angina pectoris and end-stage coronary artery disease represent an increasing clinical problem. Numbers of these patients will increase in the future for improved survival due to effective secondary prevention of coronary artery disease. Next to the evaluation of clinical symptoms non-invasive objective parameters of myocardial ischemia are of major relevance before initiation of alternative treatment modalities and for verification of antiischemic effectiveness. Based on our own experience it can be shown that in these patients testing which is mainly based on the patients physical exercise capacity is only of limited value due to the early occurrence of clinical symptoms. Furthermore diffuse perfusion abnormalities reduce the sensitivity of electrocardiographic and scintigraphic detection of ischemic changes. In contrast indirect measures of ischemia relating to the systolic or diastolic function of the left ventricle like doppler-echocardiography and radionuclide ventriculography seem to be promising approaches. This is confirmed by the results from the application of long-term intermittent urokinase therapy. Long-term intermittent urokinase therapy leads to an absolute enhancement of myocardial perfusion, which makes this approach superior to other medical interventions which are mainly based on a reduction of cardiac work-load.
...
PMID:[Assessment of the anti-ischemic effect in patients with therapy refractory angina pectoris in end-stage coronary heart disease--results of chronic intermittent urokinase therapy]. 982 80

Degenerative disease of aortocoronary saphenous vein grafts is a major cause of late morbidity and mortality in patients after coronary bypass surgery. We previously described a technique for recanalization of totally occluded grafts using extraction atherectomy (TEC) as a primary modality. While success was comparable to overnight urokinase, distal embolization, no-reflow, and non-Q myocardial infarction were common. Recently, abciximab has been used adjunctively in angioplasty and stenting with a reduced incidence of periprocedural complications. In order to determine whether abciximab can reduce the incidence of distal embolization, no-reflow, and myocardial infarction during TEC in totally occluded saphenous vein grafts, we compared patients treated with adjunctive abciximab with control subjects not receiving the drug. Male patients with previous coronary bypass surgery, class III-IV angina, and totally occluded saphenous vein grafts serving a vascular territory with ischemia not approachable by standard catheter-based techniques underwent TEC with or without adjunctive abciximab. Recanalization of the graft was achieved in 8/10 (80%) of subjects without abciximab, but complete success was achieved in only 5/10 (50%). In contrast, all procedures in the abciximab group were completely successful, without embolization or no-reflow. Our results suggest that TEC with adjunctive abciximab may be a highly effective approach for management of totally occluded saphenous vein grafts.
...
PMID:Adjunctive abciximab improves outcomes during recanalization of totally occluded saphenous vein grafts using transluminal extraction atherectomy. 1034 79


<< Previous 1 2 3 4 5 6 7 Next >>

---