Can we provide reperfusion therapy to all unselected patients admitted with acute myocardial infarction?

OBJECTIVES: This study sought to assess the maximal rate of acute Thrombolysis in Myocardial Infarction (TIMI) grade 3 patency that can be achieved in unselected patients. BACKGROUND: Early and complete (TIMI grade 3 flow) reperfusion is an important therapeutic goal during acute myocardial infarction. However, thrombolysis, although widely used, is often contraindicated or ineffective. The selective use of primary and rescue percutaneous transluminal coronary angioplasty (PTCA) may increase the number of patients receiving reperfusion therapy. METHODS: A cohort of 500 consecutive unselected patients with acute myocardial infarction were prospectively treated using a patency-oriented scheme: Thrombolysis-eligible patients received thrombolysis (n = 257) and underwent 90-min angiography to detect persistent occlusion for treatment with rescue PTCA. Emergency PTCA (n = 193) was attempted in patients with contraindications to thrombolysis, cardiogenic shock or uncertain diagnosis and in a subset of patients admitted under "ideal conditions." A small group of patients (n = 38) underwent acute angiography without PTCA. Conventional medical therapy was used in 12 patients with contraindications to both thrombolysis and PTCA. RESULTS: Ninety-eight percent of patients received reperfusion therapy (thrombolysis, PTCA or acute angiography), and angiographically proven early TIMI grade 3 patency was achieved in 78%. Among patients with TIMI grade 3 patency, thrombolysis alone was the strategy used in 37%, emergency PTCA in 40% and rescue PTCA after failed thrombolysis in 15%; spontaneous patency occurred in 8%. CONCLUSIONS: Reperfusion therapy can be provided to nearly every patient (98%) with acute myocardial infarction. Rescue and direct PTCA provided effective early reperfusion to patients in whom thrombolysis failed or was excluded.     

Diabetic retinopathy should not be a contraindication to thrombolytic therapy for acute myocardial infarction: review of ocular hemorrhage incidence and location in the GUSTO-I trial. Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries

OBJECTIVES: This study sought to evaluate the incidence of ocular hemorrhage in patients with and without diabetes after thrombolytic therapy for acute myocardial infarction. BACKGROUND: Ocular hemorrhage after thrombolysis has been reported rarely. However, there is concern that the risk is increased in patients with diabetes. In fact, diabetic hemorrhagic retinopathy has been identified as a contraindication to thrombolytic therapy without clear evidence that these patients have an increased risk for ocular hemorrhage. METHODS: We identified all suspected ocular hemorrhages from bleeding complications reported in patients enrolled in the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO)-I trial. Additional information was collected on a one-page data form. We compared the incidence and location of ocular hemorrhages in patients with and without diabetes. RESULTS: There were 40,899 patients (99.7%) with information about diabetic history and ocular bleeding. Twelve patients (0.03%) had an ocular hemorrhage. Intraocular hemorrhage was confirmed in only one patient. There were 6,011 patients (15%) with diabetes, of whom only 1 had an ocular hemorrhage (eyelid hematoma after a documented fall). The upper 95% confidence intervals for the incidence of intraocular hemorrhage in patients with and without diabetes were 0.05% and 0.006%, respectively. CONCLUSIONS: Ocular hemorrhage and, more important, intraocular hemorrhage after thrombolytic therapy for acute myocardial infarction is extremely uncommon. The calculated upper 95% confidence interval for the incidence of intraocular hemorrhage in patients with diabetes was only 0.05%. We conclude that diabetic retinopathy should not be considered a contraindication to thrombolysis in patients with an acute myocardial infarction.     

Percutaneous transluminal coronary angioplasty in acute myocardial infarction. A prospective controlled study

In the present study we compared the outcome of primary percutaneous coronary angioplasty (PTCA) (PTCA without prior or concomitant administration of thrombolytic drugs) in 82 consecutive patients with acute myocardial infarction (AMI) with the outcome of 82 AMI patients, who were treated with intravenous thrombolysis. The thrombolysis patients were prospectively matched to the angioplasty patients regarding age, sex, duration of symptoms and infarct localisation. The in-hospital mortality was 3.7% in the PTCA group versus 4.9% in the thrombolysis group. Thrombolysis-treated patients had increased use of diuretics and ACE-inhibitors as compared to PTCA-treated patients. The mean ejection fraction was 52 +/- 11% in the PTCA group versus 47 +/- 10% (p = 0.01) in the thrombolysis group. We conclude that initial Danish experience with primary PTCA is promising, and that this treatment may favourably affect the outcome of acute myocardial infarction.     

Does PTCA in acute myocardial infarction affect mortality and reinfarction rates? A quantitative overview (meta-analysis) of the randomized clinical trials

BACKGROUND: Percutaneous transluminal coronary angioplasty (PTCA) is often performed after acute myocardial infarction (AMI) either as an adjuvant to thrombolytic therapy or instead of thrombolysis. The effect of PTCA in AMI on mortality and reinfarction has remained unclear, with the available randomized trials indicating inconsistent results. METHODS AND RESULTS: A systematic overview (meta-analysis) of the randomized trials was conducted to assess the effect of PTCA in AMI on mortality and reinfarction rates. Data from 7 trials in which primary PTCA was evaluated and 16 trials in which PTCA after thrombolysis was studied were included in this overview, comprising a total of 8496 patient. The trials represented different approaches to the timing of PTCA after AMI. The trials of PTCA after thrombolytic therapy were also categorized according to the different protocols with respect to the routine or elective character of PTCA in the invasive group. A reduction in short-term (6 week) mortality (odds ratio, 0.56; 95% CI, 0.33, 0.94) and in the combined outcome of short-term mortality and nonfatal reinfarction (odds ratio, 0.53; 95% CI, 0.35, 0.80) was observed in the trials comparing primary PTCA with thrombolytic therapy. In contrast, in trials in which an approach of thrombolysis and PTCA was compared with thrombolytic therapy alone, there was no important difference in early mortality, with an apparent reduction in mortality between 6 and 52 weeks. The lower mortality between 6 and 52 weeks among 6-week survivors seemed to be restricted to the subgroup of trials in which PTCA was used as a routine strategy (odds ratio, 0.58; 95% CI, 0.39, 0.87). CONCLUSIONS: Although the analyses of the various categories of trials suggest that primary PTCA may be more beneficial than thrombolytic therapy in AMI, these data should be interpreted cautiously unless confirmed by larger studies. In contrast, the addition of various other strategies of PTCA to thrombolytic therapy does not convincingly indicate a clinically different outcome than if a more conservative strategy is followed, in which PTCA is used only if clinically indicated. Some specific strategies, however, such as rescue PTCA in high-risk patients with occluded arteries, may be of benefit.     

Thrombolysis in myocardial infarction-outcome optimization methods

Early reperfusion in acute myocardial infarction (AMI) has been shown to reduce the extent of myocardial necrosis and to improve short and long term prognosis. Gender, smoking, age and site of infarct location may be regarded as prognostic factors for the outcome of AMI and of thrombolytic therapy with streptokinase (STK). The aim of this study was to identify factors, which are related to the results of thrombolytic therapy by STK in AMI. 156 patients (122 males and 34 females) treated with STK were retrospectively analyzed: they were subdivided into 3 groups according to the presumed success of thrombolytic therapy based on the accepted clinical and angiographic TIMI flow criteria. Group 1 = successful (88 patients), group 2 = probably successful (20 patients) and group 3 = failed thrombolysis (48 patients). Multiple regression analysis showed that Killip class (p = 0.0005), time from pain onset to thrombolysis initiation (p = 0.02) and the time of the day in which thrombolysis began (p = 0.037) are independent major predictive factors for successful thrombolytic therapy by STK in AMI. Gender, age, smoking and some risk factors are not of similar predictive power. These results may guide us in the optimization of thrombolytic therapy by STK in AMI, different dose regimens for different times of day and probably preference for primary PTCA in the early morning hours.     

Percutaneous transluminal coronary angioplasty (PTCA) as primary therapy in acute myocardial infarct

BASIC PROBLEM AND OBJECTIVE: Percutaneous transluminal coronary angioplasty (PTCA) is being increasingly considered as an alternative to thrombolytic treatment of acute myocardial infarction. Studies performed so far, some on selected groups of patients, have produced high initial results of success. This prospective study was undertaken to determined primary success, complications and recurrence after primary PTCA in acute myocardial infarction (AMI). PATIENTS AND METHODS: Primary treatment in the form of immediate PTCA of the infarct vessel was undertaken in 111 patients (84 men, 27 women; mean age 58.6 +/- 10.3 years) with AMI. PTCA was judged successful if the infarct vessel had been reopened to perfusion grade 3 and restenosis was < 50%. No thrombolytic treatment was given, but heparin infusions were given during and for 24-48 hours after the procedure. 13 patients (11.7%) were in cardiogenic shock or required cardiopulmonary resuscitation for infarct-related arrhythmias. RESULTS: The primary success rate of PTCA for the whole group was 91% (101 of 111 patients), but only 77% (ten of 13) among patients in cardiogenic shock and (or) after resuscitation. Acute re-occlusion (0-6 days after PTCA) occurred in seven patients. Eight patients (7.2%) died during the hospital phase (0-4 weeks), seven of whom had been in shock or required resuscitation (death rate 54%). The overall complication rate of the intervention was 6.3%. No emergency aortocoronary bypass was necessary. Repeat coronary angiography was performed in 71 of the 101 successfully treated patients 6 or 12 weeks after the PTCA. Re-occlusion was demonstrated in four (5.6%), a restenosis of more than 50% in 25% of patients. Mean left ventricular ejection fraction, obtained by planimetry from the levocardiogram was 58.6 +/- 9.3%. CONCLUSION: PTCA, performed immediately after acute myocardial infarction is an effective therapeutic measure with a high primary success rate.     

Intracoronary administration of the combined fibrinolytic therapy a in patient with acute myocardial infarction and end-stage coronary heart disease - a case report]

Classical thrombolytic treatment in acute myocardial infarction is able to reach reperfusion in 60-80% of patients, however in 5-10% of cases reoclusion occurs. Primary percutaneous coronary intervention (PCI) offers the potential for a higher rate of reperfusion and a lower rate of bleeding events. Recently, advances in platelet inhibition and PCI procedures have led to the combination of all the approaches. Facilitated PCI or the use of elective PCI after pharmacological reperfusion therapy can combine the best aspects of thrombolysis and mechanical revascularization in acute myocardial infarction. However, in some cases PCI cannot be performed. This paper describes a patient with acute myocardial infarction successfully treated with intracoronary infusion of alteplase and GP IIb/IIIa inhibitor.     

Lions and tigers and bears, oh my!

OBJECTIVE: To examine the use of thrombolytic treatment in acute myocardial infarction when faced with perceived contraindications to treatment and to explore the justification for withholding treatment in such clinical situations. METHODS: Interview survey of all doctors responsible administering thrombolysis to patients with acute myocardial infarction at a teaching hospital in the UK from March to May 1997. RESULTS: 20 doctors were interviewed and asked whether they would give or withhold thrombolysis in a series of 19 clinical situations. These included patients presenting with both an acute myocardial infarction and one of the following associated conditions: a confirmed gastrointestinal haemorrhage, a suspected gastrointestinal haemorrhage, a peptic ulcer, an abdominal aortic aneurysm, a recent cerebrovascular accident, a known intracranial aneurysm, a known intracranial tumour, a recent dental extraction, recent surgery, severe hypertension, proliferative diabetic retinopathy, a history of bleeding diathesis, coma, recent cardiopulmonary resuscitation, pregnancy, menstruation, and a recent central venous puncture. In all but one of the clinical situations (definite current gastrointestinal haemorrhage) there was wide variation in response as to what constitutes a contraindication to thrombolytic treatment. Overall, a substantial proportion of doctors (35%-95%) would withhold treatment on account of any one of these clinical histories. CONCLUSION: Clinicians may be withholding thrombolysis in acute myocardial infarction on account of perceived contraindications for which there is little or no evidence of increased haemorrhagic risk. An effective treatment for acute myocardial infarction is probably being underused.     

Long-term beneficial effect of late reperfusion for acute anterior myocardial infarction with percutaneous transluminal coronary angioplasty

BACKGROUND: Although the short-term and long-term beneficial effects of early coronary revascularization by primary PTCA or thrombolytic therapy have been established for acute myocardial infarction, thrombolytic therapy >24 hours after the onset of acute myocardial infarction has not been shown to improve clinical outcome. The purpose of this study was to assess the effect of late revascularization by primary PTCA over a 5-year period. METHODS AND RESULTS: Eighty-three patients with initial Q-wave anterior myocardial infarction >24 hours after onset were randomized into a PTCA group (n=44) and a no-PTCA group (n=39). Long-term follow-up was conducted with regard to end points, which included cardiac death, nonfatal recurrence of myocardial infarction, and development of congestive heart failure. Left ventricular ejection fraction and regional wall motion at 6 months after myocardial infarction were similar in the 2 groups. Left ventricular end-diastolic and end-systolic volume indexes were significantly smaller in the PTCA group than in the no-PTCA group (P<0.0001). With cardiac events as end points, a 5-year Kaplan-Meier event-free survival analysis revealed that the no-PTCA group had a worse prognosis than the PTCA group (P<0.0001). Patency of the infarct-related artery, left ventricular ejection fraction, end-diastolic volume index, and end-systolic volume index were significantly associated with cardiac events by a Cox proportional hazards analysis (hazard ratios 0.120, 0.845, 1.065, and 1.164, respectively). CONCLUSIONS: In initial Q-wave anterior myocardial infarction, we conclude that even with late reperfusion, PTCA had beneficial effects on cardiac events over the 5-year period after myocardial infarction, with the prevention of left ventricular dilation after myocardial infarction being a possible mechanism.     

Effect of the antitumor drug lonidamine on glucose metabolism of adriamycin-sensitive and -resistant human breast cancer cells

The efficacies of direct percutaneous transluminal coronary angioplasty (PTCA) and thrombolysis for the treatment of acute myocardial infarction were investigated in 80 patients treated within 12 hours of the onset of myocardial infarction by either PTCA (39 patients) or thrombolytic therapy (41 patients) followed by conservative care. The therapeutic approach was selected according to the treatment strategy at each of the 16 participating centers before the admission of the patients. The two treatment groups were closely matched in clinical characteristics except for the history of hypertension which occurred more in the thrombolysis group (22/39 vs 12/41, p = 0.026). The mean time before starting reperfusion therapy from the onset of symptoms was shorter in the thrombolysis group (2.3 +/- 1.5 vs 5.3 +/- 5.7 hours, p = 0.0001). Chest pain resolved more quickly in the PTCA group. Serial changes in the mean numbers of abnormal Q waves and mean values of the sum of elevated ST-segments on the electrocardiograms were similar in both groups. Serial changes of wall motion abnormality index on echocardiograms were similar in both groups. Coronary angiography after 4 weeks showed the thrombolysis group had greater residual luminal stenosis in the infarct-related artery. Left ventriculography after 4 weeks showed the PTCA group had better mean ejection fraction (68.1 +/- 11.2% vs 58.7 +/- 14.2%, p = 0.0263). Death (3/39 vs 1/41) and cardiac events (6/39 vs 6/41) after 4 weeks were similar in both groups. There was no significant difference in death and cardiac events between these two groups. However, the PTCA group had less severe residual luminal stenosis in the infarct-related artery and better left ventricular function after 4 weeks than the thrombolysis group.     

Observations of the treatment of women in the United States with myocardial infarction: a report from the National Registry of Myocardial Infarction-I

BACKGROUND: To determine whether there are sex differences in the demographics, treatment, and outcome of patients with acute myocardial infarction in the United States, data from the National Registry of Myocardial Infarction-I from September 1990 to September 1994 were examined. METHODS: The National Registry of Myocardial Infarction-I is a national observational database consisting of 1234 US hospitals in which each hospital submits data from each patient with acute myocardial infarction to a central data collection center. For these analyses, the following variables were examined in 354 435 patients with acute myocardial infarction: demographics; use of medical therapy including thrombolytic agents; use of procedures including cardiac catheterization, percutaneous transluminal coronary angioplasty, and coronary artery bypass surgery; length of hospital stay; adverse events (stroke, major bleeding, or recurrent myocardial infarction); and causes of death. RESULTS: In comparison with men, women experiencing acute myocardial infarction in the United States are older, with 55.7% older than 70 years. Women have a higher mortality rate than men even when controlled for age and die less often from arrhythmia but more often from cardiac rupture whether or not thrombolytic therapy is used. Treatment with aspirin, heparin, or beta-blockers is less frequent in women. When thrombolytic therapy is used, women are treated an average of almost 14 minutes later than men and experience a greater incidence of major bleeding. Cardiac catheterization, percutaneous transluminal coronary angioplasty, and coronary artery bypass surgery are used less often in women. CONCLUSIONS: Observations from the National Registry of Myocardial Infarction-I document important sex differences in demographics, treatment, and outcome of patients with acute myocardial infarction in the United States.     

Influence of cigarette smoking on rate of reopening of the infarct-related coronary artery after myocardial infarction: a multivariate analysis

OBJECTIVES: This study sought to determine whether the reopening of the infarct-related vessel is related to clinical characteristics or cardiovascular risk factors, or both. BACKGROUND: In acute myocardial infarction, thrombolytic therapy reduces mortality by restoring the patency of the infarct-related vessel. However, despite the use of thrombolytic agents, the infarct-related vessel remains occluded in up to 40% of patients. METHODS: We studied 295 consecutive patients with an acute myocardial infarction who underwent coronary angiography within 15 days (mean [+/- SD] 6.7 +/- 3.2 days) of the onset of symptoms. Infarct-related artery patency was defined by Thrombolysis in Myocardial Infarction trial flow grade > or = 2. Four cardiovascular risk factors--smoking, hypertension, hypercholesterolemia and diabetes mellitus--and eight different variables-age, gender, in-hospital death, history of previous myocardial infarction, location of current myocardial infarction, use of thrombolytic agents, time interval between onset of symptoms, thrombolytic therapy and coronary angiography--were recorded in all patients. RESULTS: Thrombolysis in current smokers and anterior infard location on admission were the three independent factors highly correlated with the patency of the infarct-related vessel (odds ratios 3.2, 3.0 and 1.9, respectively). In smokers, thrombolytic therapy was associated with a higher reopening rate of the infard vessel, from 35% to 77% (p < 0.001). Nonsmokers did not benefit from thrombolytic therapy, regardless of infarct location. CONCLUSIONS: These observational data, if replicated, suggest that in patients with acute myocardial infarction, thrombolytic therapy may be most effective in current smokers, whereas nonsmokers and ex-smokers may require other management strategies, such as emergency percutaneous transluminal coronary angioplasty.     

Possibilities and limitations of thrombolysis. Benefits and risk in acute myocardial infarct, lung embolism, pelvic and leg vein thrombosis as well as cerebrovascular accidents

The indications for thrombolytic therapy in acute myocardial infarction, pulmonary embolism, deep venous thrombosis and ischemic stroke are reviewed on the basis of a risk-benefit analysis. There is strong evidence that thrombolysis benefits the majority of patients with acute myocardial infarction. Nevertheless, the overall proportion of patients actually receiving this therapy is disappointingly low (10-30%). Efforts are mainly required in minimizing delays in initiating thrombolysis (patient, doctor, in-hospital) and in providing thrombolytic therapy to an extended proportion of qualifying patients. This implies that many traditional but inappropriate exclusion criteria (e.g. age, presentation 6 to 12 hours after onset of symptoms, hypertension, reinfarction, brief cardiopulmonary resuscitation) are unfounded. Depending on duration of symptoms, infarct localization and age, we favor a differentiated thrombolytic regimen with rt-PA or streptokinase. In contrast to acute myocardial infarction, the risk-benefit ratio for the other thrombotic disorders discussed favours thrombolytic therapy only in a minority of carefully selected patients.     

Thrombolytic therapy of acute myocardial infarct--current status and new developments

Timely initiation of thrombolytic therapy can achieve coronary reperfusion, a reduction in infarct size, a preservation of left ventricular function and a reduction in mortality. It is therefore an established procedure in acute myocardial infarction. The major drawback is an increased rate of bleeding. As a consequence thrombolytic therapy is at present withheld from many patients with contraindications. Other problems include relative inefficacy of presently available thrombolytic agents and early reocclusion of primarily successfully reperfused vessels. New approaches to optimize the risk/benefit ratio for the patient and to make thrombolytic therapy available to more patients include new antithrombin and antiplatelet agents as adjunctive therapy, synergistic combinations of plasminogen activators, mutants of t-PA and prourokinase, chimeric molecules and antibody-targeted thrombolysis.     

Dietary-sodium-induced cardiac remodeling in spontaneously hypertensive rat versus Wistar-Kyoto rat

OBJECTIVE: To determine lengths and causes of pre- and in-hospital delays in thrombolytic treatment. DESIGN: A prospective national survey covering 48 of the 51 Finnish university, central and general hospitals to obtain basic data before the start of a public campaign to shorten patient-related delay in acute myocardial infarction. SUBJECTS: One thousand and twelve consecutive patients with acute myocardial infarction who received thrombolytic therapy over 3 months in 1995 and who represent 40% of all patients with confirmed acute myocardial infarction. RESULTS: The median interval between onset of infarction symptoms and initiation of thrombolytic therapy was 160 min (30-647). Only 13% of the patients received thrombolysis within 60 min and 38% within 120 min. The median time from the onset of symptoms to the call for help was 60 min (5-491), and no difference was found in patients with or without a history of previous myocardial infarction (60 and 64 min, respectively). Only 52% of the patients called to the dispatch centre. The median delay from calling for help to hospital arrival was 40 min (10-170). The median in-hospital door-to-needle thrombolysis delay was 40 min (12-196). In 13% of hospitals the median delay was more than 60 min. The emergency physician encountered difficulties in decision making in 33% of cases. CONCLUSIONS: Only 38% of the patient received thrombolysis within 2 h of onset of symptoms. Patient-related delay before they sought help accounted for the major portion of the total treatment delay. Thus the findings emphasize the importance of prompt action when people are confronted with an acute heart attack. Reorganizing the emergency medical service and emergency department routines is also a necessary target to shorten thrombolysis delays. The delay attributable to transporting patients could be shortened by initiating thrombolytic treatment in the pre-hospital setting. In Finnish hospitals, door-to-needle delay was acceptable in cases with clear indications for thrombolysis. However, emergency physicians often had diagnostic difficulties, which led to remarkably longer in-hospital delays.     

Improvement in the treatment of acute myocardial infarct by the establishment of a thrombolysis unit in a cardiology servic

INTRODUCTION AND OBJECTIVES: Lack of available beds in the coronary care unit, makes time to thrombolysis still too long. Although fibrinolytic therapy is administered in the emergency department in most hospitals, mean in-hospital delay continues to be long. Our purpose was to improve the treatment of these patients and to evaluate if this delay could be shortened by creating a thrombolysis unit for the treatment of patients with acute myocardial infarction. METHODS: A thrombolysis unit in the cardiology department was set up to treat patients with acute myocardial infarction who couldn't be admitted directly in the coronary care unit because of lack of available beds. Time to treatment in both groups of patients were compared. RESULTS: Two hundred twenty-five patients with acute myocardial infarction and ST-segment elevation were included: 86 (38%) of them were admitted to the thrombolysis unit and the other 139 (62%) to the coronary care unit. There were no differences in baseline characteristics or in the pre-hospital delay between both groups. Time from hospital admission to thrombolysis was 59 minutes in patients treated in the thrombolysis unit versus 70 minutes in those treated in the coronary care unit (p < 0.001), and time from the admission to both units to fibrinolytic therapy was of 20 minutes versus 30 minutes respectively (p < 0.0001). There were no differences between both groups in the incidence of complications. CONCLUSIONS: In-hospital delay in thrombolysis remains too long. Implementation of a thrombolysis unit in the cardiology department shortens this delay and offers the possibility to treat patients with acute myocardial infarction at least as well as in the coronary care unit, without dependence on the availability of free beds in this unit.     

Immediate angioplasty compared with the administration of a thrombolytic agent followed by conservative treatment for myocardial infarction. The Mayo Coronary Care Unit and Catheterization Laboratory Groups

BACKGROUND: Immediate angioplasty and the administration of a thrombolytic agent followed by conservative treatment are two approaches to the management of acute myocardial infarction, but these methods have not been compared prospectively. METHODS: We enrolled 108 patients with acute myocardial infarction in a randomized trial designed to test the hypothesis that immediate angioplasty (without previous thrombolytic therapy) may result in greater myocardial salvage than the administration of a thrombolytic agent followed by conservative treatment. The primary end point was the change in the size of the perfusion defect as assessed at admission and discharge by tomographic imaging with technetium-99m sestamibi, a myocardial perfusion agent that can measure myocardium at risk and final infarct size. RESULTS: End-point data were available for 56 patients randomly assigned to receive tissue plasminogen activator (mean [+/- SD] time to start of infusion, 232 +/- 174 minutes after the onset of chest pain) and 47 patients randomly assigned to receive angioplasty (first balloon inflation at 277 +/- 144 minutes). In the case of anterior infarction, myocardial salvage as assessed by imaging with technetium-99m sestamibi was 27 +/- 21 percent of the left ventricle for 22 patients in the thrombolysis group, as compared with 31 +/- 21 percent for 15 patients in the angioplasty group. For infarcts in all other locations, myocardial salvage was 7 +/- 13 percent for 34 patients in the thrombolysis group and 5 +/- 10 percent for 32 patients in the angioplasty group. After adjustment for infarct location, the difference in mean salvage between groups was 0 (P = 0.98), with a 95 percent confidence interval of +/- 6 percent of the left ventricle. CONCLUSIONS: In patients with acute myocardial infarction, immediate angioplasty does not appear to result in greater myocardial salvage than the administration of a thrombolytic agent followed by conservative treatment, although a small difference between these two therapeutic approaches cannot be excluded.     

Serial changes of plasma plasminogen activator inhibitor activity in acute myocardial infarction: difference between thrombolytic therapy and direct coronary angioplasty

The fibrinolytic system is impaired in patients with acute myocardial infarction (AMI). The primary regulatory element of fibrinolytic activity is plasminogen activator inhibitor (PAI). There are no reports, however, on the serial changes of PAI activity after thrombolysis or coronary angioplasty in patients with AMI undergoing emergency coronary angiography. This study was designed to examine the difference in the change of fibrinolytic activity between patients with AMI who underwent thrombolytic therapy with recombinant tissue-plasminogen activator (rTPA) and those who underwent direct percutaneous coronary angioplasty (PTCA). We measured the serial changes of PAI activity and tissue plasminogen activator (TPA) antigen after rTPA therapy or direct PTCA. Twenty-two patients received emergency coronary angiography and were treated with rTPA intravenously. Twenty patients underwent direct PTCA. Plasma PAI activity levels were increased on admission and further increased within 24 hours in patients treated with rTPA and in those treated with direct PTCA. In the thrombolysis group, there were two peaks in plasma PAI activity levels (IU/ml) at 4 hours (27.0 +/- 2.9) and at 16 hours (25.6 +/- 2.5) after the initiation of rTPA infusion. However, in the direct PTCA group, there was one peak of PAI activity (IU/ml) at 16 hours (23.9 +/- 2.7) after the initiation of direct PTCA. In conclusion, the PAI activity has two peaks in the thrombolysis group and one peak in the direct PTCA group.     

Thrombolysis following myocardial infarct. European Secondary Prevention Study

For evaluation of the management of patients with acute myocardial infarction, all cases of ten Zurich hospitals (278, 184 men and 94 women) in the period from 1 January to 31 March 1993 were analyzed retrospectively. 223 patients were released from hospital, 55 died. A follow-up was done 6 months after the patient's discharge by means of a questionnaires to the family doctor (return rate: 65.9%). 48.5% of patients were referred to hospital within the first 6 h. after onset of symptoms, 64% within the first 12 h. 28% (n = 76) of the patients received a thrombolytic therapy, of which 91% (n = 69) got streptokinase and 9% (n = 7) got tissue plasminogen activator. In 81% of the cases the thrombolytic therapy was done within the first hour in hospital, in accumulated 97% of the cases within two hours. In the age group under 65 years (39% of the patients, n = 109), 48 patients received thrombolysis (odds ratio [OR] = 1.0). In the age group between 65 and 74 years (24.5 % of the patients, n = 68), 19 patients received thrombolysis (OR: 0.49; 95% CI: 0.42-0.99; p < 0.05), and in the age group over 74 years (36.5% of the patients, n = 101), 9 patients were received thrombolysis (OR: 0.12; 95% CI: 0.05-0.28; p < 0.0001). 31% of the patients (n = 46) received a coronary angiography, 15% (n = 22) had coronary angioplasty, and 11% (n = 1) received coronary bypass surgery. There is evidence that there should be more importance attached to early hospitalization, if acute myocardial infarction is suspected. Thereby age alone should be considered as a contraindication for thrombolytic therapy. The issue of assumed underuse of thrombolytic therapy should be investigated all over Switzerland.     

The 60 Minutes Myocardial Infarction Project. Characteristics on admission and clinical outcome in patients with reinfarction compared to patients with a first infarction

PURPOSE: The purpose of the study was to evaluate parameters that characterize patients with myocardial reinfarction as compared to patients with a first infarction in clinical practice, and possibly to determine their clinical outcome. METHODS: The 60 minutes Myocardial Project is a German multicentre prospective observational study in which 136 hospitals are participating. Fourteen thousand, nine hundred and eighty consecutive patients with acute Q wave myocardial infarction were included from July 1992 to September 1994. RESULTS: Out of these 14,980 patients, there were 2854 (19%) with reinfarction and 12,126 (81%) with a first infarction. Patients with a reinfarction arrived at the hospital 24 min earlier than patients with a first infarction (pre-hospital delay 156 vs 180 min; P < 0.001); the door-to-needle time with reinfarction was longer (38 vs 30 min; P < 0.001); however, patients with reinfarction were older (69 vs 66 years; P < 0.001), had a lower rate of a diagnostic first ECG (54 vs 71%; P < 0.001) and received thrombolytic therapy less frequently than patients with a first infarction (46 vs 52%; P < 0.001). A low number of patients received primary PTCA ( n = 205) since only a few hospitals offered a primary PTCA service at the time the study was performed. In patients with reinfarction, there were more reasons as to why thrombolytic therapy was not given (24 vs 21%; P < 0.001). Left bundle branch block occurred more frequently in patients with reinfarction (15 vs 8%; P < 0.001). The intra-hospital course in patients with reinfarction was associated with an increase of complications and intra-hospital death (23 vs 15%; P < 0.001. CONCLUSIONS: Although reinfarction patients arrived earlier at hospital than patients with a first infarction, the former received thrombolytic therapy less frequently than the latter. Patients with reinfarction were older, more frequently had a non-diagnostic ECG on admission and had a higher rate of contraindications against thrombolytic therapy.