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Biomedical subjects

S G Ellis

Publications and source records attributed to S G Ellis.

At least 199 records · Page 11Linked to original sources
PubMed1990

Relationship between antecedent angina pectoris and short-term prognosis after thrombolytic therapy for acute myocardial infarction. Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) Study Group.

The relationship between preinfarction clinical status and short-term outcome was prospectively evaluated in 775 patients hospitalized with acute myocardial infarction after reperfusion therapy. It was anticipated that a history of angina preceding myocardial infarction by more than 7 days would be associated with more extensive underlying coronary artery disease and a more complicated in-hospital course. However, although this group did have a higher risk profile for coronary artery disease (hypertension 53.6% vs 37.2%; diabetes 22.5% vs 12.1%; hyperlipidemia 19.4% vs 9.8%; mean number of risk factors 2.2 vs 1.7, p = 0.0001), a higher incidence of multivessel disease (57.7% vs 39.6%, p less than 0.0001), worse baseline global left ventricular function (left ventricular ejection fraction 48.8% vs 51.3%, p = 0.03), and impaired function of the noninfarct zone (-0.05 vs +0.46 SD/chord, p = 0.002), the in-hospital course was less complicated than in the group without prior angina. Patients without antecedent angina had a higher rate of reocclusion of the infarct-related artery (13.6% vs 8.2%; p = 0.048). Although the difference did not reach statistical significance (7.2% vs 4.6%; p = 0.21), the in-hospital mortality rate was also higher in this group. These findings suggest that a history of prior angina is not necessarily associated with an unfavorable short-term prognosis after reperfusion therapy. This may be related to the greater prior use by this group of beta-adrenergic- and calcium channel-blocking agents (23.1% vs 8.5% and 20.7% vs 3.8%, respectively). It may also be related to the beneficial effects of collateral vessels, myocardial preconditioning, or differences in the native fibrinolytic system.

Aged↗
PubMed1990

Intravenous recombinant tissue-type plasminogen activator in patients with unstable angina pectoris. Results of a placebo-controlled, randomized trial.

Because thrombus formation may contribute to coronary obstruction in patients with unstable angina pectoris, we performed a pilot investigation to determine whether thrombolytic therapy can relieve coronary narrowing in this acute ischemic syndrome. Sixty-seven patients with rest angina and angiographic evidence of coronary stenosis were randomly assigned to receive either low-dose intravenous recombinant tissue-type plasminogen activator (rt-PA) (0.75 mg/kg over 1 hour), high-dose intravenous rt-PA (0.75 mg/kg over 1 hour; total dose, 100 mg over 6 hours), or intravenous placebo followed by repeat coronary angiography at 24-48 hours to assess change in the severity of coronary narrowing. Each patient also received oral aspirin and intravenous heparin. Mean values of coronary stenosis severity (percent of diameter reduction) declined to a similar extent in each group: placebo, 75 +/- 14% to 72 +/- 14% (p = 0.07); low-dose rt-PA, 75 +/- 16% to 71 +/- 18% (p = 0.03), and high-dose rt-PA, 82 +/- 11% to 77 +/- 17% (p = 0.18), with only the low-dose rt-PA group achieving statistical significance. Resolution of intracoronary filling defects, increase in antegrade flow grade, or both also occurred equally among the three groups. There was considerable variation in individual patient response. Between 29% and 50% of patients within each group demonstrated a decrease in stenosis severity, whereas 50% to 57% noted either improvement in antegrade flow or resolution of intracoronary thrombus. There was no difference in incidence of major bleeding events among the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Coronary morphologic and clinical determinants of procedural outcome with angioplasty for multivessel coronary disease. Implications for patient selection. Multivessel Angioplasty Prognosis Study Group.

To assess the likelihood of procedural success in patients with multivessel coronary disease undergoing percutaneous coronary angioplasty, 350 consecutive patients (1,100 stenoses) from four clinical sites were evaluated. Eighteen variables characterizing the severity and morphology of each stenosis and 18 patient-related variables were assessed at a core angiographic laboratory and at the clinical sites. Most patients had Canadian Cardiovascular Society class III or IV angina (72%) and two-vessel coronary disease (78%). Left ventricular function was generally well preserved (mean ejection fraction, 58 +/- 12%; range, 18-85%) and 1.9 +/- 1.0 stenoses per patient had attempted percutaneous coronary angioplasty. Procedural success (less than or equal to 50% final diameter stenosis in one or more stenoses and no major ischemic complications) was achieved in 290 patients (82.8%), and an additional nine patients (2.6%) had a reduction in diameter stenosis by 20% or more with a final diameter stenosis 51-60% and were without major complications. Major ischemic complications (death, myocardial infarction, or emergency bypass surgery) occurred in 30 patients (8.6%). In-hospital mortality was 1.1%. Stepwise regression analysis determined that a modified American College of Cardiology/American Heart Association Task Force (ACC/AHA) classification of the primary target stenosis (with type B prospectively divided into type B1 [one type B characteristic] and type B2 [greater than or equal to two type B characteristics]) and the presence of diabetes mellitus were the only variables independently predictive of procedural outcome (target stenosis modified ACC/AHA score; p less than 0.001 for both success and complications; diabetes mellitus: p = 0.003 for success and p = 0.016 for complications). Analysis of success and complications on a per stenosis dilated basis showed, for type A stenoses, a 92% success and a 2% complication rate; for type B1 stenoses, an 84% success and a 4% complication rate; for type B2 stenoses, a 76% success and a 10% complication rate; and for type C stenoses, a 61% success and a 21% complication rate. The subdivision into types B1 and B2 provided significantly more information in this clinically important intermediate risk group than did the standard ACC/AHA scheme. The stenosis characteristics of chronic total occlusion, high grade (80-99% diameter) stenosis, stenosis bend of more than 60 degrees, and excessive tortuosity were particularly predictive of adverse procedural outcome. This improved scheme may improve clinical decision making and provide a framework on which to base meaningful subgroup analysis in randomized trials assessing the efficacy of percutaneous coronary angioplasty.

Angiography↗
PubMed1990

Intracoronary stents: clinical and angiographic results.

Limitations of current forms of coronary angioplasty including abrupt vessel closure and delayed restenosis have led to the development of alternative nonsurgical methods of coronary revascularization. By scaffolding the arterial dissection and smoothing the endoluminal surface, intracoronary stenting may obviate the need for emergency coronary bypass surgery in patients who develop abrupt vessel closure following coronary angioplasty. As primary therapy, its use may prevent or delay restenosis in high-risk patients; however, due to potential patient selection bias, controlled studies are needed. Currently available intracoronary stents are limited by varying degrees of inflexibility, radiolucency, and thrombogenicity. These limitations have resulted in the development of innovative stent designs using radioopaque tantalum filaments and aggressive pharmacologic treatment with antiplatelet and anti-thrombotic therapy following stent deployment. Current experimental investigation into the feasibility of intracoronary stent coating with genetically engineered endothelial cells or slow release antiproliferative agents, such as colchicine or methotrexate, may further serve to lessen the frequency of late restenosis. The optimal patient selection criteria for the use of the intracoronary stent is currently the subject of intense clinical investigation.

Coronary Angiography↗
PubMed1990

Interventions in acute myocardial infarction.

Results of multiple studies have amply verified the benefit of urgent coronary revascularization for patients who have acute myocardial infarction (MI). Currently, intravenous thrombolytic therapy is the treatment of choice for many patients, especially those 75 years old or younger who present within 6 hours of symptom onset and who are without contraindications to thrombolytic therapy. Some patients treated within 6-24 hours of symptom onset may also benefit, but this remains unproven. The thrombolytic agents currently in use or being extensively evaluated include streptokinase, urokinase, tissue-type plasminogen activator (t-PA), anisoylated plasminogen streptokinase activator complex (APSAC or anistreplase), and single-chain urokinase-type plasminogen activator (scu-PA). The agent t-PA has the potential advantage of being clot selective and, thereby, relatively fibrinogen sparing, and its efficacy in terms of restoration of vessel patency is less dependent on the time of administration as compared with that of streptokinase and urokinase. It is not yet known whether this will translate into improved patient survival as compared with that achieved by the less-expensive agents streptokinase and APSAC. Treatment regimens of combination thrombolytic agents have been developed, but the optimal combinations have not yet been determined. Patients who are in cardiogenic shock and those in whom thrombolytic therapy is contraindicated can probably benefit from angioplasty or bypass surgery. Results of several studies have suggested that immediate angioplasty after successful thrombolysis is not beneficial; however, the potential benefit of angioplasty or bypass surgery for failed thrombolytic therapy is yet to be evaluated. Although many advances have been made, further research is clearly needed in the area of reperfusion.

Angioplasty, Balloon, Coronary↗
PubMed1989

Risk factors, time course and treatment effect for restenosis after successful percutaneous transluminal coronary angioplasty of chronic total occlusion.

Advances in technology and operator experience, and increased use of angiography early after myocardial infarction have led to greater use of percutaneous transluminal coronary angioplasty (PTCA) for chronic, total coronary artery occlusions. To better assess long-term outcome, 257 consecutive patients with successful PTCA of a total occlusion with late angiographic follow-up from 484 patients (53%) with PTCA success were reviewed. The mean +/- standard deviation patient age was 54 +/- 10 years, 79% were men, the duration of total occlusion was 11 +/- 15 weeks and the post-PTCA diameter stenosis was 24 +/- 12%. Eighty-two, 27 and 63% of patients received long-term aspirin, dipyridamole and warfarin therapy, respectively. Angiography at 8 +/- 8 months demonstrated restenosis (greater than or equal to 50% diameter stenosis) in 41% of patients restudied within 6 months and in 66% of patients restudied within 12 months by life table analysis. In multivariate regression analysis of 19 variables, 2 were independently correlated with the occurrence of restenosis: post-PTCA diameter stenosis greater than 30% (p = 0.02) and coronary artery dilated (left anterior descending and right coronary arteries greater than the left circumflex coronary artery) (p = 0.05). In log rank analysis that also considered the timing of angiographic detection of restenosis, dilatation of a proximal left anterior descending stenosis was also a significant predictor of restenosis (p = 0.01), and dilatation within 4 weeks of the presumed time of occlusion was only weakly predictive (p = 0.11).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1989

Incidence and predictors of early recurrent ischemia after successful percutaneous transluminal coronary angioplasty for acute myocardial infarction.

Two hundred forty consecutive patients with acute myocardial infarction treated within 48 hours by successful percutaneous transluminal coronary angioplasty (PTCA) were analyzed to determine the incidence and predictors of recurrent ischemic events during hospitalization. Thirty-nine patients had recurrent ischemia: 20 patients had chest pain or electrocardiographic changes requiring repeat PTCA or bypass surgery, or resulting in a second creatine kinase elevation suggestive of myocardial infarction; 12 had total occlusion of the dilated artery on follow-up angiography; and 7 had exercise-induced ischemia and greater than or equal to 70% diameter stenosis that required PTCA or bypass surgery before hospital discharge. In-hospital mortality was 15% in the recurrent ischemia group, compared to 1% in the group without recurrent myocardial ischemia (p less than 0.001). Angiographic follow-up before hospital discharge was obtained in 198 patients, including 38 of the 39 patients with ischemic events. Thus, the true incidence of recurrent ischemic events was between 39 of 199 and 39 of 240, or 16 and 20%. In multivariate analyses, recurrent ischemia was predicted by translesional gradient greater than 25 mm Hg (p = 0.001), dissection (p = 0.01) and post-PTCA Thrombolysis in Myocardial Infarction 2 flow pattern (p = 0.016). However, even in the absence of these risk factors recurrent ischemic events occurred in 13% of patients. Post-PTCA percent diameter stenosis (whether assessed by objective or visual assessment), degree of the early systemic fibrinolytic state, post-PTCA residual minimal diameter and concomitant use of thrombolytic agents were not predictive.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1989

Importance of stenosis morphology in the estimation of restenosis risk after elective percutaneous transluminal coronary angioplasty.

To determine the importance of predilatation stenosis morphology on the risk of restenosis after percutaneous transluminal coronary angioplasty (PTCA), 500 procedures were randomly chosen for analysis from 3,839 consecutive successful PTCA procedures. Angiographic follow-up was available for 308 patients (62%) at a mean of 7.3 +/- 3.4 months after PTCA. One dilated site was randomly chosen per procedure. One hundred and one sites had documented restenosis (greater than or equal to 50% mean diameter stenosis from multiple projections) by quantitative angiography (33% of all sites restudied and 20% of all sites dilated). Twenty-eight morphologic variables and 20 other angiographic, clinical and procedural variables were analyzed by an observer blinded to clinical outcome. Univariate analysis found post-PTCA percent stenosis greater than 30% (p = 0.005), bend point location (p = 0.01), post-PTCA gradient greater than 15 mm Hg (p = 0.02), angina class III to IV (p = 0.03), age (p = 0.04) and the absence of dissection (p = 0.04) to predict restenosis. Multivariate analysis found only 2 significant (p less than 0.05) independent predictors of restenosis: post-PTCA percent stenosis greater than 30% and bend point location. Restenosis occurred in 41% of lesions located at an end-diastolic vessel angle greater than or equal to 45 degrees compared with 28% in lesions on lesser bends. Thus, only 1 predilatation morphologic characteristic, stenosis location at a bend point, was an important independent predictor of restenosis, and should be considered when assessing patients for PTCA.

Angioplasty, Balloon↗
PubMed1989

Comparison of coronary angioplasty with medical treatment for single- and double-vessel coronary disease with left anterior descending coronary involvement: long-term outcome based on an Emory-CASS registry study.

The 3 to 5-year clinical outcomes of 627 consecutive patients selected for treatment with percutaneous transluminal coronary angioplasty (PTCA) at Emory University Hospital for one- or two-vessel coronary artery disease with involvement of the left anterior descending coronary artery, between July 1981 and June 1983, and 865 patients in the Coronary Artery Surgery Study with similar coronary artery disease involvement selected for medical therapy between 1975 and 1979 were compared. Cox analyses and stratified life table analyses were used to adjust for differences in 13 variables including concurrent medical therapy. Complete follow-up was obtained in 97% of PTCA patients and 99% of medically treated patients. After correction for baseline differences in significantly predictive variables, there was no difference between the relative risk of death after PTCA vs medical therapy (RR = 0.7; p = 0.36). However, results of analysis of prospectively defined subsets showed a potential survival benefit after PTCA for patients with an ejection fraction less than 50% (RR = 0.2; p = 0.02) and also for patients with two-vessel disease (RR = 0.2; p = 0.04). For the groups as a whole there was no difference in risk of infarction after PTCA and medical therapy (RR = 0.8; p = 0.58). However, for patients with 90% to 99% LAD stenosis there was a trend toward lessened risk of infarction after PTCA (RR = 0.6; p = 0.15). No patient subset had a higher risk of death or infarction with PTCA (p less than or equal to 0.15). The likelihood of later surgery was increased after PTCA (RR = 1.5; p = 0.002). Angina, employment, and activity levels were improved after PTCA. Thus PTCA compared to medical therapy was associated with improved functional status and may decrease the risk of death and infarction in certain patient subsets. However, bypass surgery was more often performed in patients initially treated with PTCA. These data should be interpreted in light of their nonrandomized study origin and generation from different clinical sites.

Activities of Daily Living↗
PubMed1989

Long-term follow-up of patients treated with coronary angioplasty for acute myocardial infarction.

Long-term follow-up data for patients treated with coronary angioplasty (PTCA) for acute myocardial infarction are limited. Therefore the long-term outcome of 336 consecutive patients treated with PTCA at a median of 4.5 hours (range 0.5 to 48 hours) from symptom onset was evaluated. The in-hospital mortality was 11.1% (37 patients). Follow-up is complete for 293 of 299 (98%) hospital survivors at a median of 24 months. Of patients discharged, the mean age was 55 +/- 11 years, 49% received intravenous thrombolytic therapy, 53% had multivessel coronary artery disease, and the mean ejection fraction was 48 +/- 10%. Post-discharge survival was 96.1% at 1 year and 93.6% at 2 years by life table analysis. Post-discharge survival was independently predicted by no prior myocardial infarction (96.9% versus 87.3% 2-year survival, p less than 0.001 by log rank analysis) and infarct artery patency at hospital discharge (which had its major impact on survival early after hospital discharge: [97.4% versus 93.4% 1-year survival but 94.2% versus 93.4% 2-year survival; overall p = 0.02]). For patients with analyzable ventriculograms at hospital discharge, ejection fraction greater than or equal to 40% was also a significant independent predictor of survival (98.1% versus 85.8% 2-year survival, p = 0.01). For patients with a successful PTCA, time from symptom onset to catheterization and angioplasty less than or equal to 4 hours versus greater than 4 hours was also an independent predictor of outcome (97.1% versus 91.4% 2-year survival; p = 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1989

Effect of 18- to 24-hour heparin administration for prevention of restenosis after uncomplicated coronary angioplasty.

Smooth muscle cell proliferation induced by intimal denudation similar to that produced by coronary angioplasty has been decreased by early and brief heparin administration in animal models. Heparin might also decrease the incidence of thrombus-induced postdenudation arterial obstruction, albiet at risk of bleeding. To evaluate the risks and benefits of heparin after coronary angioplasty, 416 patients (469 vessel sites) with successful coronary angioplasty without large dissection were randomized to heparin (titrated to partial thromboplastin time 1.5 to 2.5 times normal) or dextrose administered for 18 to 24 hours. Patients also had received heparin during angioplasty (usually 10,000 to 15,000 units), and they received aspirin for a period of 6 months. Heparin and dextrose groups were not different in the percentage of patients with male sex (74% in the heparin group and 75% in the dextrose group, p = NS), postangioplasty tear or dissection (30% in the heparin group and 30% in the dextrose group, p = NS), or postangioplasty percent stenosis greater than 35% (31% in the heparin group and 30% in the dextrose group, p = NS). Partial thromboplastin time during treatment in the heparin group was 56 +/- 22 seconds and in the dextrose group 27 +/- 9 seconds (p less than 0.001). Late angiographic follow-up (180 +/- 81 days) was achieved in 58.4% in the heparin group and 64.5% in the control group. Of patients with late angiographic follow-up, 41.2% and 36.7% randomized to heparin and dextrose, respectively, had documented restenosis (greater than or equal to 50% diameter stenosis at one or more the sites dilated) (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

Coronary angioplasty as primary therapy for acute myocardial infarction 6 to 48 hours after symptom onset: report of an initial experience.

Recent randomized trials in acute myocardial infarction suggest that infarct size reduction need not be achieved for intravenous streptokinase to improve patient survival. If this is the case, attempts to achieve late revascularization may be justified. To assess the results of late primary coronary angioplasty performed in the setting of acute myocardial infarction, the clinical and angiographic data as well as hospital outcome of 139 consecutive patients treated with coronary angioplasty without prior thrombolytic therapy 6 to 48 h after the onset of chest pain (late group) were compared with those of 117 patients treated with primary angioplasty less than 6 h after the onset of chest pain (early group); time to angioplasty was assessed as a covariate of survival. In the 139 patients treated greater than or equal to 6 h after the onset of chest pain, the mean age (+/- SD) was 57 +/- 12 years and the median time to angioplasty was 15 h; 61% had multivessel disease, 14% were in cardiogenic shock and the mean left ventricular ejection fraction was 44 +/- 12%. Angioplasty was successful (final diameter stenosis less than 70% and Thrombolysis in Myocardial Infarction [TIMI] flow grade greater than or equal to 2) in 78% of patients. Successful angioplasty was associated with a 5.5% in-hospital mortality rate, whereas unsuccessful angioplasty was associated with a 43% hospital mortality rate (p less than 0.001). Multivariate testing in all patients identified four independent predictors of in-hospital death: cardiogenic shock (p less than 0.001), unsuccessful angioplasty (p = 0.001), ejection fraction less than or equal to 30% (p = 0.002) and patient age (p = 0.004).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

Implications for patient triage from survival and left ventricular functional recovery analyses in 500 patients treated with coronary angioplasty for acute myocardial infarction.

The in-hospital course of 500 consecutive patients treated with coronary angioplasty for acute myocardial infarction was reviewed in relation to their clinical and angiographic presentation and angioplasty outcome to determine which patients benefit most from successful angioplasty in this setting. Patient age was 56 +/- 11 years (mean +/- SD) and 78% were men; 46% had anterior myocardial infarction, 49% received concomitant intravenous thrombolytic therapy, left ventricular ejection fraction was 47 +/- 11% and median time to angioplasty was 4.7 h (range 1 to 24). Angioplasty was successful in 78% of patients and partially successful in 7% of patients; the overall in-hospital mortality rate was 10.2%. Multivariate analysis found six independent correlates (p less than 0.05) of in-hospital mortality: left ventricular ejection fraction less than or equal to 30%, lack of postangioplasty infarct artery patency, age greater than 65 years, recurrent ischemia after successful angioplasty, emergency bypass surgery and arterial pressure on admission to the catheterization laboratory less than 100 mm Hg. After consideration of these predictors of survival in multivariate analyses, angioplasty success still was independently correlated with improved in-hospital survival for patients with cardiogenic shock (p = 0.002) and anterior myocardial infarction (p = 0.007). A trend toward an independent beneficial effect of successful angioplasty on survival was also noted in patients with inferior wall infarction and precordial ST segment depression (p = 0.063) and for all patients who were hypotensive on admission to the catheterization laboratory, regardless of the infarct site (p = 0.057).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1989

Intracoronary stents: will they fulfill their promise as an adjunct to angioplasty?

Coronary angioplasty as it is now performed has several limitations, including abrupt early arterial closure and delayed restenosis. To obviate these problems and to enhance the safety of the technique, several intracoronary stenting devices have been developed and are under investigation. This report reviews the scientific rationale behind stenting, the results of stenting in animal models and the early results in humans. In early clinical investigation, restenosis appears uncommon but abrupt, presumably thrombotic, occlusion has been reported despite aggressive anticoagulation. As long as the potential for this problem remains and the long-term consequences of placing these devices into arteries of great functional importance remain unknown, stent placement must be undertaken with great caution and should be performed under carefully monitored circumstances with meticulous patient follow-up.

Angioplasty, Balloon↗
PubMed1989

Combined tissue-type plasminogen activator and prostacyclin therapy for acute myocardial infarction. Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) 4 Study Group.

Current limitations of recombinant tissue-type plasminogen activator (rt-PA) therapy for acute myocardial infarction include failure to achieve recanalization in 25% of patients, reocclusion and reperfusion injury. Iloprost, a stable analogue of prostacyclin (PGI2), has been demonstrated to facilitate thrombolysis and reduce myocardial stunning in experimental models. To evaluate combined therapy, rt-PA (100 mg 3 h) and Iloprost (2 ng/kg per min for 48 h) were administered to 25 patients and then rt-PA alone (same dose) was given to an additional 25 patients with evolving myocardial infarction. At 90 min after drug administration, infarct-related vessel patency was observed in 11 (44%) of 25 who received rt-PA plus Iloprost compared with 15 (60%) of 25 who received rt-PA alone (p = 0.26). At 1 week, reocclusion had occurred in 3 (14%) of 21 patients who received combined therapy compared with 6 (26%) of 23 patients treated with rt-PA alone (p = 0.46). Ejection fraction increased significantly from baseline to 7 days for rt-PA alone whereas it decreased with combined therapy (rt-PA alone whereas it decreased with combined therapy (rt-PA alone: 47.3 +/- 11.5% at baseline to 50.4 +/- 9.8% at 7 days; rt-PA plus Iloprost: 51.3 +/- 10.1% at baseline to 49.0 +/- 9.4% at 7 days; difference between groups p = 0.05). At 4 h after therapy, fibrinogen decreased 33% for rt-PA plus Iloprost compared with a 52% for rt-PA alone (p = 0.001). Fibrinogen degradation products increased 60% more for rt-PA alone than for rt-PA plus Ilprost. Thus, the combination of rt-PA plus Iloprost at the doses employed did not improve immediate or follow-up coronary artery patency or left ventricular functional recovery compared with that achieved with rt-PA alone.

Cardiovascular Agents↗
PubMed1989

Randomized, double-blind, placebo-controlled trial of tissue plasminogen activator in unstable angina.

Angiographic, angioscopic and pathologic reports have recently demonstrated a high incidence of intracoronary thrombus in patients with unstable angina. To determine if thrombolysis could be beneficial when combined with maximal medical therapy, 40 patients with rest angina, angiographically documented coronary artery disease and pacing-induced ischemia were randomly assigned to intravenous recombinant tissue-type plasminogen activator (rt-PA, 150 mg/8 h) or placebo in a prospective double-blind trial. All patients received nitrates, a beta-adrenergic blocking agent, a calcium channel blocker, aspirin and heparin. Pacing thresholds for ischemia and quantitative coronary stenosis were measured before and after infusion of the study medication. Intracoronary thrombus was identified angiographically before infusion of the study medication in 16 patients; 7 received rt-PA and 9 received placebo. The ischemic pacing threshold in patients treated with rt-PA increased from 112 +/- 4 beats/min at baseline to 127 +/- 5 beats/min (p = 0.007) by the end of the infusion versus an insignificant change in patients who received placebo (from 116 +/- 4 to 119 +/- 4 beats/min, p = NS). In patients with intracoronary thrombus, the ischemic pacing threshold increased 26 +/- 7 beats/min with rt-PA treatment versus 0 +/- 3 beats/min with placebo (p = 0.004). In contrast, in patients without thrombus, there was no difference in ischemic pacing threshold increments between treatment groups (7 +/- 11 beats/min for rt-PA versus 6 +/- 5 beats/min for placebo, p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗