Coronary thrombolysis for evolving myocardial infarction

An acute thrombus at the site of an atherosclerotic obstruction is the usual cause of myocardial infarction. Thrombolytic therapy is an exciting new therapy for reducing the extent of myocardial infarction by lysing intracoronary clots. Such therapy has now been widely applied by: prolonged intravenous infusion of streptokinase during the first 24 hours of infarction; intracoronary infusion of streptokinase, urokinase, or tissue plasminogen activator; early, high dose, brief duration intravenous infusion of streptokinase; or intravenous infusion of tissue plasminogen activator. Intracoronary streptokinase or urokinase achieves reperfusion of the coronary artery in 75% of patients and is associated with serious bleeding in 4.8% of patients. Intravenous infusion of streptokinase achieves reperfusion of the coronary artery in 50 to 80% of patients. The incidence of serious bleeding with intravenous streptokinase averaged 0.8% in 5 studies of 237 patients and was 12.8% in 1 additional study of 80 patients. Salvage of the jeopardised myocardium and improvement in left ventricular function occurred when coronary reperfusion was achieved. Mortality in streptokinase-treated patients was significantly reduced at 30 days and at 6 months after infarction in the single randomised mortality study done to date; however, more data are needed on this important question. Reocclusion after thrombolysis averages 17% in patients treated with streptokinase by either intracoronary or intravenous infusion. The newly reperfused coronary artery has been stabilised in some patients by coronary bypass surgery or percutaneous transluminal angioplasty, but further studies are needed to define criteria for appropriate patient selection for these procedures.

Coronary thrombolysis by intravenous streptokinase in acute myocardial infarction: acute and follow-up studies

Coronary arteriography was performed before, immediately after, and 9 to 14 days after administering i.v. streptokinase (850,000 to 1,500,000 IU) to 43 patients within 6 hours of myocardial infarction. Ventricular function was determined by contrast ventriculography before and 9 to 14 days later and by radionuclide studies at clinical follow-up 8 months later. Early reperfusion occurred in 49% of patients, but in only 35% was it sustained. In patients with sustained reperfusion, early ventricular dysfunction was significantly reduced 9 to 14 days and 10 months later, and frequency of infarction, sudden death, and angina pectoris was not increased at follow-up. No serious bleeding occurred.

Nightmares and trauma: a comparison of nightmares after combat with lifelong nightmares in veterans

In this study the chronic traumatic nightmares of men who had been in combat were found to differ from the lifelong nightmares of veterans with no combat experience in that they tended to occur earlier in the sleep cycle, were more likely to be replicas of actual events, and were more commonly accompanied by gross body movements. Traumatic nightmares may arise out of varying stages of sleep and are not confined to REM sleep alone. The group with lifelong nightmares showed evidence of thought disorder on the Rorschach. The men with posttraumatic stress disorder had failed to psychologically integrate their traumatic experiences and used dissociation as a way of dealing with strong affects.

High-dose, brief intravenous streptokinase early in acute myocardial infarction

An acute thrombus at the proximal border of a high-grade atherosclerotic obstruction is the usual cause of myocardial infarction. Although intracoronary thrombolysis is potentially an exciting new therapy for reducing the extent of myocardial infarction by lysing coronary clot, a number of major difficulties limit its widespread application. It is a complex procedure requiring intracoronary visualization and infusion within a few hours of onset of symptoms. Since intravenous streptokinase could be widely applied if effective, we and others have wondered whether high-dose, brief-duration intravenous streptokinase infusion given early in myocardial infarction would lyse coronary clots without bleeding. To date we have treated 13 patients within 6 hours of onset of symptoms and with ECG and angiographic evidence of typical myocardial infarction caused by coronary clot. Clot lysis and angiographically proved coronary reperfusion were achieved in 6 patients within 1 hour of starting a systemic intravenous infusion of 850,000 IU of streptokinase. Schroeder et al., in Berlin, West Germany, achieved angiographically proved coronary reperfusion in 11 of 21 patients with acute myocardial infarction following a 30-minute intravenous streptokinase infusion of 500,000 IU. Neuhaus et al., in Göttinen, West Germany, achieved angiographically proved coronary reperfusion in 24 of 39 similar patients within 48 minutes by intravenous infusion of 1,700,000 IU of streptokinase. In these three studies, no serious bleeding occured; left ventricular function was improved in patients who achieved coronary reperfusion. We conclude that rapid intracoronary clot lysis and coronary reperfusion can be achieved early in myocardial infarction by brief-duration systemic intravenous infusion of high-dose streptokinase without a high incidence of serious bleeding.

The anturane reinfarction trial

The Anturane Reinfarction Trial evaluated the effect of sulfinpyrazone (Anturane) (200 mg four times a day) vs placebo on cardiac mortality rates among patients recently recovered from an acute myocardial infarction. This study involved 1558 eligible patients who were observed for an average period of 16 months (maximum 2 years). The trial differed from studies on other platelet-active drugs in that it was designed as a clinical efficacy study rather than an "intent-to-treat" trial, and all patients were entered within a very narrow window, i.e., 25-35 days after infarction, which allowed for the drug to be evaluated against the natural history of mortality after an acute myocardial infarction. At the end of the trial, there were 105 analyzable cardiac deaths among eligible patients. 62 in the placebo group and 43 in the sulfinpyrazone group; this represented a reduction in mortality rate by sulfinpyrazone of 32% and was of borderline statistical significance (p = 0.044-0.058 using three methods of analysis). This reduction was attributable primarily to a significant reduction in sudden death (37 in the placebo group vs 22 in the sulfinpyrazone group, sudden death mortality reduction of 43%, p = 0.023-0.041). Interpretation of the data by time period and cause revealed that the effect of sulfinpyrazone was restricted to the prevention of sudden death during the high-risk period for this event, i.e., the first 6 months after trial entry (24 in the placebo group vs six in the sulfinpyrazone group, sudden death mortality reduction of 74%, p = 0.001-0.003).

Sulfinpyrazone: a review of its pharmacological properties and therapeutic use

Sulfinpyrazone1 has long been recognised as a potent uricosuric agent, but has more recently been studied extensively as a platelet inhibitor and antithrombotic agent. It is active in man following oral administration and has been reported to be effective in reducing the incidence of transient ischaemic attacks, thromboembolism associated with vascular and cardiac prostheses, recurrent venous thrombosis, arteriovenous shunt thrombosis and sudden cardiac death following myocardial infarcton. Sulfinpyrazone has not been demonstrated to be effective in preventing or reducing the risk of stroke or death in patients with cerebrovascular disease with a recent history of cerebral or retinal ischaemioc attacks. The normal total dose of sulfinpyrazone as an antithrombotic agent is 800mg daily. The drug has been used continuously for up to 4 years with no serious adverse reactions or laboratory abnormalities. There has been no apparent diminution of effect with time. Sulfinpyrazone is not a substitute for conventional anticoagulant agents (e.g. the coumarin derivatives) in the treatment of venous thrombosis, but is an important drug for the treatment of conditions associated with arterial thrombosis and possibly for the prophylaxis of recurrent venous thrombosis.

Drug trials in myocardial infarction. Lessons to be learned from the Anturane Reinfarction Trial

Drug intervention trials in myocardial infarction are unlikely to prove an effect unless planning takes into consideration: (1) the multiple causes for cardiac mortality after myocardial infarction, and the likelihood that the drug being tested is unlikely to affect all of these causes; (2) the different mortality rates at different periods following the qualifying infarct; (3) the contribution of each cause to the total mortality encountered during each period; and (4) the elimination of the various dilution factors which plague those trials based only on an intention to treat rather than on the efficacy of the drug when administered properly to eligible patients. Prospective studies should be designed with these points in mind. Otherwise one will be confronted with the usual criticisms and scepticism associated with a retrospective analysis. In this regard, the Anturane Reinfarction Trial represents an advance in trial design, and the lessons to be learned from it provide a basis for further improvements.

[Sulfinpyrazone in the prevention of sudden death after myocardial infarction (author's transl)]

The results of the Anturane Reinfarction Trial, a randomized, double-blind, multicenter clinical trial, represent the data on 1558 patients who received either sulfinpyrazone or placebo for an average of 16 months, starting 25 to 35 days after a documented myocardial infarction. All but one of the 106 deaths at 24 months were cardiac. In the sulfinpyrazone group the reduction in cardiac mortality was 32 per cent (P =0,058) and the reduction in sudden death was 43 per cent (P = 0,041). The benefit of sulfinpyrazone was attributable to a reduction in sudden death during the second through seventh month after infarction, when there were 24 sudden deaths in the placebo group and only six in the sulfinpyrazone group - a sulfinpyrazone - induced 74 per cent reduction in the calculated mortality rate (P = 0,003).

Controlled trial of low-dose heparin and sulfinpyrazone to prevent venous thromboembolism after operation on the hip

A randomized, double-blind controlled trial of low-dose heparin combined with sulfinpyrazone to prevent deep-vein thrombosis after operation on the hip was carried out. In a group of seventy-three patients after arthroplasty, postoperative thrombosis of the veins of the lower limbs occurred in 51 per cent of the control patients and in 36 per cent of the treated patients. In a fracture group of thirty patients, thrombosis occurred in 75 per cent of the control patients and in 36 per cent of the treated patients. These differences are of borderline statistical significance in the fracture group and are of no statistical significance in the arthroplasty group. However, a 36 per cent incidence of venous thrombosis in the drug-treated patients is too high to justify recommendation of the regimen tested without careful monitoring of patients by tests designed to detect thrombosis. Then, appropriate anticoagulant therapy can be instituted if necessary.

Preventing pulmonary embolism with heparin in low doses

The introduction of low-dose heparin prophylaxis of thrombosis in deep leg veins represents a major advance in clinical medicine. It approaches an ideal form of prophylaxis in that it can be given easily to large numbers of patients at risk, requires no monitoring, is relatively safe, and, used widely, should save many lives. Conservative estimates are that 5,000 postoperative deaths and a comparable number of medical deaths can be avoided in the United States alone. Further inroads on this important problem will require additional developments, some of which are well under way.