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

Despite the compelling relationship between early treatment and outcome from reperfusion therapy in patients with acute myocardial infarction, significant delays in early treatment are imposed by the patient, prehospital systems, and hospital processes and protocols used in the identification and treatment of patients with myocardial infarction. A survey instrument designed to determine the prevalence of hospital policies and protocols that might delay or expedite treatment with thrombolytic therapy in patients with acute myocardial infarction was completed by 524 hospital participating in the National Registry for Myocardial Infarction (NRMI). Participating hospitals had treated 17,646 patients with tissue plasminogen activator. The door to drug time for the entire population of patients treated at each hospital was available. Door to drug times were compared between those hospitals that had a positive response to a policy and those that had a negative response to that policy. Among respondent hospitals, thrombolysis was excluded by protocol in 34.4% for age above 75 and in 55% for presentation after 6 hours of chest pain onset. Furthermore, 29.4% of hospitals required routine laboratory testing other than electrocardiography (ECG), including chest x-ray, prior to determination of eligibility for thrombolysis. Door to drug times were shorter in those hospitals with prehospital 12-lead ECG availability, assessment of the 12-lead ECG by the emergency department nurse and physician as soon as it was available, and initiation of thrombolysis by the emergency physician (in patients with clear-cut ST elevation myocardial infarction) without bedside cardiology consultation. Door to drug times were longer in those hospitals in which predecision laboratory results were required, written informed consent was mandated, and drug was initiated in the cardiac intensive care unit rather than in the emergency department itself. Door to drug times were not significantly different in those hospitals with a designated chest pain center compared with those operating under a focused patient care protocol. We conclude that the earliest possible hospital treatment of acute myocardial infarction patients may be precluded by multiple components of emergency department policies and process, many of them inappropriate for safe, efficient, and effective identification and management of these patients.
 ...
PMID:Hospital Protocols and Policies that may Delay Early Identification and Thrombolytic Therapy of Acute Myocardial Infarction Patients. 1060 59

Hepatocyte growth factor (HGF), a cytokine involved in tissue regeneration, angiogenesis and lateral vessel growth, is secreted as a biological-inactive, single-chain precursor named pro-HGF. In case, of tissue injury pro-HGF is proteolytically cleaved at the extracellular locus by serine proteases. Results obtained from in vitro experiments showed that urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) can cleave single-chain HGF. In this study we measured serum HGF levels in patients with acute myocardial infarction (MCI). Two groups of patients were compared. One group (n = 7) was treated with a conventional therapy and the other group (n = 7) was subjected to a thrombolytic therapy with recombinant tissue-type plasminogen activator (rtPA). Serum samples were collected at time of admission and subsequently 12-16 hours, 20-30 hours and 50-60 hours after onset of chest pain. At admission and before administration of rtPA, serum HGF levels peaked at 16.8 +/- 2.2 ng/ml in the lysed group and at 20.7 +/- 6.5 ng/ml in the non-lysed group. Levels then continuously declined, reaching lowest values 50-60 hours after onset of chest pain (3.2 +/- 1.3 ng/ml in the group treated with rtPA versus 4.4 +/- 0.9 ng/ml in the non-lysed group). No statistical significant difference could be detected between the two groups at any time. We suggest that serine proteases other than tPA are involved in HGF activation in vivo.
 ...
PMID:Hepatocyte growth factor plasma levels after myocardial infarction are not affected by recombinant tissue-type plasminogen-activator therapy. 1070 4

The objective of this study were to assess the impact of a quality assurance effort on the door-to-needle time and the choice of thrombolytic agent for the management of acute myocardial infarction in the emergency department. The study design involved a prospective collection of data on a series of consecutive patients who received a thrombolytic agent for a presumed acute myocardial infarction. The study was carried out in the emergency department of a major university urban tertiary care center. A total of 349 patients were studied from September 1989 to March 1994. The quality assurance program began in 1989 and included chart review of all patients receiving thrombolytic therapy, with special attention to all patients with door-to-needle times >60 minutes to identify causes for delay. Feedback was directed to pharmacy, nursing, and physician staff. Biannual reports were distributed throughout the hospital and the emergency department. Nursing-specific feedback led to the development of protocols for all aspects of the delivery of thrombolytic agents. The choice of thrombolytic agent was not dictated by the protocol, but the physician staff was continuously updated on the results of the latest clinical trials comparing one thrombolytic agent with another. The mean age was 58 years for men and 67 years for women in this cohort consisting of 78% men and 22% women. Thirty-seven percent of the myocardial infarctions were in an anterior location and 56% were in an inferior location. The median duration of chest pain before presentation to the emergency department was 120 minutes. Hospital mortality was 3%. Median door-to-needle time fell from 46 (1989-1991) to 36 (1992-1994) minutes, P& < 0.01. The percentage of patients with a door-to-needle time >60 minutes decreased from 35% (1989-1991) to 16% (1992-1994) minutes, P < 0.0001. Corresponding with the ISIS-3 report, there was a significant increase in the proportion of patients receiving streptokinase over the first 3 years of the study (P < 0.0001), which changed to a trend toward increased utilization of tissue plasminogen activator with the GUSTO report in the final 6 months of the study. In conclusion, a quality assurance program led to a significant reduction in the door-to-needle time, and recent megatrials were found to influence the choice of thrombolytic agent used.
 ...
PMID:Impact of a Simple Inexpensive Quality Assurance Effort on Physician's Choice of Thrombolytic Agents and Door-to-Needle Time: Implication for Costs of Management. 1076 10

Previous reports indicate that patients who do not develop Q waves after thrombolytic therapy are a different population with a better long-term survival than those who do develop Q waves. However, the use of resources, quality of life, and health status of this population have not been fully evaluated. Using data from the Economics and Quality of Life subset of the Global Utilization of Streptokinase and tPA for Occluded Arteries study, we examined 30-day and 1-year mortality, use of resources, and quality-of-life measures among 1,830 of 3,000 patients with acute myocardial infarction and ST-segment elevation treated with thrombolytic therapy. At hospital discharge, 555 patients (30.2%) had not developed Q waves. These patients had lower mortality than patients with Q waves at 30 days (1.6% vs 4.5%, p <0.01) and at 1 year (4.7% vs 6.8%, p <0.04). Recurrent chest pain and dyspnea were similar at 30 days and 1 year. Patients without Q waves had significantly more angiography and trends toward higher readmission, revascularization, and use of calcium antagonists at 30 days. Angiography, revascularization, readmission, and quality of life were equivalent from 30 days to 1 year, with no sign of late instability. Logistic regression analysis showed an association between in-hospital revascularization and better survival and quality of life at 1 year. Conversely, there was no association between in-hospital use of calcium antagonists and outcome to explain the lower mortality in non-Q-wave patients. The absence of Q waves after thrombolytic therapy is a marker of success, implying better prognosis and equivalent quality of life, use of resources, and health status than for patients with Q-wave acute myocardial infarction and no sign of long-term unstable clinical course.
 ...
PMID:Use of resources, quality of life, and clinical outcomes in patients with and without new Q waves after thrombolytic therapy for acute myocardial infarction (from the GUSTO-I trial). 1086 87

In acute myocardial infarction (AMI), immediate beta-blocker therapy reduces the incidence of reinfarction and recurrent chest pain in patients receiving tissue plasminogen activator (t-PA). Data from the Thrombolysis in Myocardial Infarction (TIMI)-2 trial also raises the possibility that such therapy may reduce the rate of intracranial hemorrhage (ICH). We reviewed data obtained from 60,329 patients treated with t-PA who were enrolled in the National Registry of Myocardial Infarction 2. Of the 60,329 in the study cohort, 23,749 patients (39.4%) were treated with immediate beta-blocker therapy and 542 patients (0.9%) developed an ICH. In a multivariate model that included all covariates known to be associated with the development of ICH, immediate beta-blocker therapy was associated with a 31% reduction in the ICH rate (odds ratio 0.69, 95% confidence intervals 0.57 to 0.84). Thus, in the present study, the use of immediate beta-blocker therapy in patients with AMI treated with t-PA was associated with a significant reduction in ICH. This finding supports the observations made in the TIMI 2 trial and serves to reinforce the recommendations made by the American College of Cardiology/American Heart Association task force that immediate beta-blocker therapy should be administered to all patients with AMI who do not have contraindications to this therapy.
 ...
PMID:Intracranial hemorrhage rates and effect of immediate beta-blocker use in patients with acute myocardial infarction treated with tissue plasminogen activator. Participants in the National Registry of Myocardial Infarction-2. 1107 95

The goal of this study was to examine the relationship between contrast agent type (ionic vs. nonionic) and angiographic, electrocardiographic, and clinical outcomes after thrombolytic administration. Ionic or nonionic contrast agents were selected in a nonrandomized fashion for 90-min angiography and percutaneous coronary intervention (PCI) following thrombolytic administration in the TIMI 14 trial [tissue plasminogen activator (tPA) or reteplase (rPA) vs. low-dose lytic + abciximab]. There was no relationship between contrast agent type and overall patency, rate of TIMI grade 3 flow, or corrected TIMI frame counts (CTFCs) in open culprit arteries and in post-PCI patency rates or post-PCI CTFCs. In patients treated with ionic contrast, ejection fractions at 90 min were slightly but significantly lower (56.2 +/- 16.5, n = 122, vs. 59.8 +/- 14.4, n = 322; P = 0.02), chest pain duration was longer (2.8 +/- 4.1 hr, n = 255, vs. 1.7 +/- 3.6, n = 550; P = 0.0003), and complete ST segment resolution was less frequent (41.5% vs. 50.8%; P = 0.04). While there was no difference in epicardial blood flow, ionic contrast agent use was associated with poorer ST segment resolution, longer chest pain duration, and poorer ejection fractions, perhaps as a result of microvascular dysfunction.
 ...
PMID:Impact of contrast agent type (ionic versus nonionic) used for coronary angiography on angiographic, electrocardiographic, and clinical outcomes following thrombolytic administration in acute myocardial infarction. 1132 10

The effect of acute myocardial infarction on plasma levels of testosterone in men is unclear. No previous studies have evaluated the bio-available fraction of testosterone. Low plasma testosterone levels have been associated with several risk factors for myocardial infarction, including an unfavorable fibrinolytic profile. In a prospective, case control study, we examined changes in plasma levels of sex hormones, including bio-available testosterone, in patients with acute myocardial infarction and in control subjects. In addition, changes in hormone levels in patients were compared with alterations in the fibrinolytic profile. Thirty male patients admitted with chest pain were studied. Twenty two had acute myocardial infarction and eight had non-specific chest pain. Plasma levels of total and bio-available testosterone, 17beta-estradiol, sex hormone binding globulin and insulin were measured at baseline and throughout admission. In addition, fibrinolytic factors (plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA) and fibrinogen) were measured in patients who received fibrinolysis. Height and weight, and the subsequent development of heart failure or myocardial dysfunction were also recorded. Patients had lower levels of bio-available testosterone (2.07 +/- 0.75 nmol/L vs. 5.3 +/- 1.7 nmol/L, p < 0.05) and higher levels of 17beta-estradiol (87.9 +/- 39.5 pmol/L vs. 48.1 +/- 18.4 pmol/L, p < 0.001) than controls. Total and bio-available testosterone levels fell acutely following myocardial infarction (11.9 +/- 3.8 nmol/L to 9.7 +/- 3.3 nmol/L, p < 0.05; 1.95 +/- 0.76 nmol/L to 1.55 +/- 0.67 nmol/L, p < 0.05). This reduction was associated with elevation of PAI-I activity and reduction of tPA activity, independent of changes in plasma insulin levels. Patients with lower baseline levels of testosterone and higher levels of 17beta-estradiol had a relatively pro-thrombotic fibrinolytic profile and increased risk of complications. In conclusion, total and bio-available levels of testosterone fall following acute myocardial infarction in men, in association with adverse changes in fibrinolytic profile. It is not clear whether this association represents a direct effect of testosterone on thrombotic tendency but warrants further investigation.
 ...
PMID:Bio-available testosterone levels fall acutely following myocardial infarction in men: association with fibrinolytic factors. 1248 66

Direct PTCA is a treatment of choice in patients with acute myocardial infarction with ST segment elevations (STEMI). Fibrinolysis remains important modality of treatment in these patients. Currently, there are more then 100 tissue plasminogen activator mutants available with different fibrin specificity. In a clinical practice, tissue-type plasminogen activator (t-PA), recombinant tissue-type plasminogen activator (rt-PA), tenecteplase (TNK-tPA) and lanoteplase (n-PA) are most important examples. Fibrinolytic treatment in STEMI patients should be used in patients presenting in first 4 hours after beginning of chest pain, when it is sure, that direct PTCA cannot be started within next 90 minutes. Concomittant therapy of acute STEMI patients consists of anticoagulans, antiplatelet and antiagregatory treatment.
 ...
PMID:[Fibrinolytic therapy in acute myocardial infarct]. 1463 19

To determine whether tenecteplase (TNK-t-PA), a bioengineered variant of tissue-type plasminogen activator (t-PA) designed to accelerate thrombolysis, exhibits favorable properties compared with those of alteplase, 266 men were studied </=6 hours after the onset of symptoms and signs of acute myocardial infarction. The primary end point was the rapidity of recanalization as judged from analysis of serial changes in the concentrations in blood of isoforms of creatine kinase-MM in serially obtained blood samples. Additional end points included enzymatically estimated infarct size and mortality. Patients were treated quite promptly after the onset of symptoms. The interval from the onset of chest pain to recanalization seen with TNK-t-PA was 208 +/- 10 (SE) minutes compared with 237 +/- 9 minutes seen with alteplase (p = 0.04). Thirty-day mortality was low with the use of the 2 agents (2%). TNK-t-PA appears to induce recanalization more rapidly than alteplase, and thrombolysis initiated early after the onset of symptoms is associated with remarkably low mortality.
 ...
PMID:Comparison of rapidity of coronary recanalization in men with tenecteplase versus alteplase in acute myocardial infarction. 1519 14

Patent foramen ovale is considered as a potential risk factor for stroke owing to paradoxic embolism, leading to the question "to close or not to close the patent foramen ovale". We report a 26-year-old woman with chest pain, dyspnoea, sudden severe pain in both legs and paraplegia. Thoracic and abdominal computed tomography revealed massive pulmonary embolism and complete obstruction of the abdominal aorta. Interventional removal of the aortic thrombus was undertaken using the Fogarty catheter technique via the femoral arterial approach. As a result of worsening of cardiopulmonary function during the procedure, additional local thrombolysis, with a total of 50 mg recombinant tissue plasminogen activator, and fragmentation of the thrombus in the right pulmonary artery were performed via a femoral vein approach. Ultrasound studies revealed a patent foramen ovale of about 12 mm diameter with a significant right to left shunt. Under favourable conditions, a patent foramen ovale may allow the escape of a thrombus, sufficient to cause a potentially fatal pulmonary embolism, into the arterial system, where it can be removed by interventional manoeuvres.
 ...
PMID:Patent foramen ovale as lifesaving purging valve. 1681 88


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>