Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.68 (tissue plasminogen activator)
 11,311 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Promazine hydrochloride was injected accidentally in the antecubital artery of a 42-year-old woman, resulting in severe ischemia of the second and third fingers of her right hand which lasted for four days before she was hospitalized. Vasodilation by combining axillary plexus block and intravenous sodium nitroprusside did not improve ischemia and local thrombolysis was performed using recombinant tissue-type plasminogen activator (50 mg over 8 hours), resulting in normalization of digital pressure in one of the two affected fingers. The outcome was favourable and amputation could be avoided.
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PMID:Severe ischemia of the hand following intra-arterial promazine injection: effects of vasodilation, anticoagulation, and local thrombolysis with tissue-type plasminogen activator. 211 16

Although both the European Cooperative Study Group and the Thrombolysis in Myocardial Infarction IIB trial indicated that angiography and angioplasty as routine measures after thrombolytic treatment do not improve clinical outcome in patients with acute myocardial infarction, the potential benefit of angioplasty may have been negated by the fact that the procedure was performed too soon (less than 32 hours) after admission. A similar study was designed in which delayed invasive treatment was compared with conservative treatment in 201 patients with acute myocardial infarction given recombinant tissue-type plasminogen activator. The 97 patients randomized to the invasive group underwent routine coronary angiography and angioplasty 5 +/- 2 days after thrombolytic therapy, whereas the 104 patients randomized to the conservative group underwent angiography only for recurrent postinfarction angina or exercise-induced ischemia. Baseline characteristics of both groups were similar. In the invasive group, 92 patients underwent angiography, 49 angioplasty and 11 coronary artery bypass surgery. In the conservative group, 40 patients experienced early ischemia, 39 underwent angiography, 20 angioplasty and 4 coronary artery bypass surgery. Reinfarction rate and preservation of left ventricular function at discharge or 8 weeks after discharge did not differ in the 2 groups. Total mortality after a mean follow-up of 10 months was 8 of 97 in the invasive and 4 of 104 in the conservative groups (p = 0.15). However, if only patients who died after the timing of the scheduled protocol catheterization in the invasive arm were included, mortality was 5 of 94 and 0 of 100 in the invasive and conservative treatment groups, respectively (p = 0.02). (ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Randomized controlled trial of late in-hospital angiography and angioplasty versus conservative management after treatment with recombinant tissue-type plasminogen activator in acute myocardial infarction. 211 99

When conventional treatment of patients with early clinical reinfarction after thrombolytic therapy fails, mechanical revascularization may be attempted. An alternative strategy, repeat thrombolytic infusions, is reported. Fifty-two patients with acute myocardial infarction were treated with one or two additional thrombolytic infusions of recombinant tissue-type plasminogen activator (rt-PA) because of nonsustained ischemia after initial treatment with rt-PA or streptokinase. Thirty-five patients received the second infusion within 1 h of the first; 13 patients received the second infusion 1 to 72 h after the first and 4 patients received it later during their hospitalization. Bleeding complications occurred in 10 patients (19%); however, most of these were minor (no intracranial bleeding) and only 2 patients required blood transfusion. In 14 patients in whom the decrease in fibrinogen and plasminogen levels was measured after the first and second infusions, this decrease was only 25% and 63%, respectively--only slightly higher than the 22% and 53% decreases measured in 63 patients who had only one rt-PA infusion. In 44 patients (85%), the acute ischemia resolved completely within 1 h after initiation of the second infusion. In 23 patients (44%), pain and ST segment elevation did not recur and invasive coronary intervention was avoided. Thus, repeat rt-PA infusions can stabilize a substantial number of patients with acute reinfarction and, even when relief is temporary, repeat rt-PA infusions can minimize myocardial damage while patients await mechanical revascularization.
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PMID:Repeat infusion of recombinant tissue-type plasminogen activator in patients with acute myocardial infarction and early recurrent myocardial ischemia. 212 Mar 9

Patients with unstable angina pectoris who remain symptomatic despite medical treatment are at high risk of death and myocardial infarction. The incidence of refractory unstable angina was examined in a consecutive series of 103 patients who received conventional medical treatment with nitrates, beta blockers, calcium antagonists and aspirin. During 48 hours of continuous electrocardiographic monitoring, 24 patients had greater than or equal to 1 anginal attack, 5 of whom had both painful and painless ischemic episodes. In these 24 patients with unstable angina refractory to conventional medical treatment, the short-term efficacy of recombinant tissue-type plasminogen activator (rt-PA) followed by heparin was assessed and compared with heparin alone in a randomized double-blind trial. Recurrences of ischemic attacks during a 72-hour follow-up period were documented in 9 of the 12 patients given heparin alone. All patients experienced at least 1 symptomatic ischemic episode and 1 patient had both painful and painless ischemia. No patient given rt-PA plus heparin had either symptomatic or asymptomatic ischemic attacks during follow-up. Kaplan-Meier curves analysis demonstrated a significantly higher probability of being ischemia free in the group of patients treated with rt-PA followed by heparin than in the group treated with heparin alone (p less than 0.01). Quantitative coronary arteriography failed to reveal any significant changes of ischemia-related lesions before and after each treatment. This study demonstrates that the combination of rt-PA and heparin has a greater protective effect than heparin alone in treating recurrent ischemic episodes in patients with refractory unstable angina.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Recombinant tissue-type plasminogen activator followed by heparin compared with heparin alone for refractory unstable angina pectoris. 212 Oct 16

Reported is the case of a patient with vertebrobasilar artery ischemia who received tissue plasminogen activator with resulting hemorrhage into the tongue and nearly exsanguinating hemorrhage from a branch of the lingual artery. Suggestions for immediate management of the hemorrhage as well as prevention are presented. As the use of thrombolytic agents increases and the list of their indications expands, unusual life-threatening hemorrhagic problems other than gastrointestinal or intracranial bleeding will be seen, and management decisions may be life saving.
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PMID:Tissue plasminogen activator-associated lingual artery hemorrhage. 212 Oct 76

The fibrinolytic system of the peritoneum is important in the pathogenesis of adhesions. Plasminogen activator activity is depressed by serosal types of injury, which cause ischemia. Ischemic peritoneum induces fibrinous adhesions. When local fibrinolytic activity is impaired, persistence of fibrin and organisation of the fibrinous adhesions may occur. Peritoneal adhesion in rabbits were created by drying the serosa of the uterine horns and by introducing a small amount of blood intraperitoneally. In one group of rabbits tissue-type plasminogen activator (t-PA) was given intraperitoneally at the end of the operation: another group served as controls. 48 rabbits were operated on. The animals were killed 3 h, 1, 3 and 7 days postoperatively for evaluation of adhesions. All animals of the control group had adhesions. The animals of the t-PA group had less adhesions than the animals of the control group.
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PMID:Prevention of postoperative adhesions by tissue-type plasminogen activator (t-PA) in the rabbit. 212 63

A prospective randomized study was undertaken in 50 patients treated with intravenous thrombolysis (streptokinase, tissue plasminogen activator, association of the two thrombolytics) for acute myocardial infarction to determine the best time to perform percutaneous transluminal coronary angioplasty (PTCA). Coronary angiography was carried out 24 to 72 hours after thrombolysis. This investigation allowed identification of the patients in whom PTCA was technically feasible. These patients were then divided into two groups: Group A: early PTCA (24-72 hours) and Group B: delayed PTCA (8-10 days). During the hospital period, the patients were prescribed heparin therapy and aspirin. Recurrent ischemia (RI) was investigated and treated by PTCA. The criteria of success of strategies A and B were a primary success of PTCA and no RI during the hospital period. Coronary angiography was performed in 108 successive patients of whom 50 were included for the comparative trial, 25 in Group A and 25 in Group B. In group A, PTCA was successful in 24 cases and there were 2 incidents of RI (6 hours and 12 days). In Group B, 4 episodes of RI were observed in the 24 hours following coronary angiography: after 10 days, 15 of the 20 patients with uncomplicated courses underwent PTCA; 1 patient refused consent, 2 regressions of stenosis and 3 asymptomatic reocclusions were observed. A primary success of PTCA was obtained in 13 of the 15 patients. There was no statistically significant difference between the results of the strategies adopted in Groups A and B. A therapeutic success was obtained in 22 of the 25 patients in Group A, and 19 of the 25 patients in Group B.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Immediate delayed coronary angioplasty after intravenous thrombolysis in myocardial infarction. Prospective study]. 212 55

We studied the relationship between thrombolysis and late potentials (LP) in 137 patients with acute myocardial infarction (AMI). Among 37 patients treated with tissue-type plasminogen activator(t-PA treated group), LP were recorded in 2 patients (5%). In contrast, among 100 conventionally treated patients (control group), LP were seen in 26 (26%, P less than 0.01). When the two groups were matched with respect to age, sex, absence of prior infarction, LVEF, number of abnormal Q waves, ECG score and CAD score, the same incidence of LP was seen, i.e. 6% of the 34 t-PA treated patients had LP as compared with 24% of the 42 conventionally treated patients (P less than 0.05). Angiographic examination following t-PA infusion revealed that the incidence of LP was 0% and 40% in patients with patent and closed infarct-related coronary artery respectively. 1 year follow-up data showed that no deaths occurred in the t-PA treated group, while in the control group. 18 deaths were recorded and 8 of them were classified as sudden death. These observations suggest that patients with AMI treated early with thrombolysis have electrically more stable ventricles due to improvement of ischemia.
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PMID:[The relationship between tissue type plasminogen activator therapy and ventricular late potentials in acute myocardial infarction]. 212 51

The effect of anoxia and reoxygenation on the synthesis and secretion of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) was studied in primary cultures of human umbilical vein endothelial cells. Sublethal anoxia, determined by trypan blue dye exclusion and lactate dehydrogenase release, was produced by cell culture under a 95% N2, 5% CO2 atmosphere for 2-24 h and was followed by reoxygenation with 95% air, 5% CO2 for 24 or 48 h. Anoxia did not alter the levels of mRNA for t-PA or PAI-1 in the cells or the secretion of t-PA or PAI-1 into the medium. At 24 h, t-PA secreted into conditioned medium was 7.0 +/- 1.4 ng/2 x 10(6) cells (n = 9) and PAI-1 was 300 +/- 13 IU/2 x 10(6) cells (n = 9), whereas the content of t-PA mRNA was 2.2 pg/micrograms of RNA and PAI-1 mRNA was 180 pg/micrograms of RNA. During reoxygenation, however, t-PA antigen and PAI-1 activity as well as mRNA for PAI-1 decreased proportionally to the duration of anoxia, to reach 27 +/- 1.0, 49 +/- 2.0, and 47 +/- 14% of control values, respectively, within 24 h of anoxia. t-PA mRNA also decreased significantly during reoxygenation following anoxia, but the extent could not be accurately quantitated. Addition, during anoxia, of a 200 micrograms/ml concentration of the superoxide anion radical scavenger superoxide dismutase or of a 5 mM concentration of the iron chelator deferoxamine mesylate prevented the subsequent decrease of t-PA antigen during reoxygenation; addition of these compounds during reoxygenation had no effect. Superoxide dismutase, but not deferoxamine mesylate, when added during anoxia prevented the subsequent decrease in PAI-1 activity. These studies suggest that the marked alteration of endothelial cell fibrinolysis during anoxia followed by reoxygenation is most likely mediated by a mechanism dependent on oxygen radicals. Impaired endothelial cell fibrinolysis may contribute to the pathophysiology of ischemia/reperfusion injury.
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PMID:Oxygen radicals generated during anoxia followed by reoxygenation reduce the synthesis of tissue-type plasminogen activator and plasminogen activator inhibitor-1 in human endothelial cell culture. 212 75

Infarct artery patency rates at 90 minutes after coronary thrombolysis using recombinant tissue-type plasminogen activator (rt-PA) with and without concurrent heparin anticoagulation have been shown to be comparable. The contribution of heparin to efficacy and safety after thrombolysis with rt-PA is unknown. In this pilot study, 84 patients were treated within 6 hours of onset of acute myocardial infarction (mean of 2.7 hours) with the standard dose of 100 mg of rt-PA over 3 hours. Forty-two patients were randomized to receive additionally immediate intravenous heparin anticoagulation (5,000 U of intravenous bolus followed by 1,000 U/hour titrated to a partial thromboplastin time of 1.5 to 2.0 times control) while 42 patients received rt-PA alone. Coronary angiography performed on day 3 (48 to 72 hours, mean 57) after rt-PA therapy revealed infarct artery patency rates of 71 and 43% in anticoagulated and control patients, respectively (p = 0.015). Recurrent ischemia or infarction, or both, occurred in 3 (7.1%) anticoagulated patients and 5 (11.9%) control patients (difference not significant). Mild, moderate and severe bleeding occurred in 52, 10 and 2% of the group receiving anticoagulation, respectively, and 34, 2 and 0% of patients in the control group, respectively (p = 0.006). These data indicate that after rt-PA therapy of acute myocardial infarction, heparin therapy is associated with substantially higher coronary patency rates 3 days after thrombolysis but is accompanied by an increased incidence of minor bleeding complications.
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PMID:Effect of heparin on coronary arterial patency after thrombolysis with tissue plasminogen activator in acute myocardial infarction. 212 2


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