Changes by two-dimensional echocardiography in the myocardial appearance of patients with end-stage renal disease.

A retrospective study of the clinical and biochemical data of all patients with end-stage renal disease who underwent 2-dimensional echocardiography at Tulane Medical Center between 1982 and 1986 was performed. Complete echocardiographic data were available for comparison in 53 patients. Highly reflective echoes were judged to be present in the myocardium of 81% of the patients. This characteristic is described as a "glistening speckled appearance." Patients with this characteristic had significantly greater left ventricular mass index (p = 0.0021).

Overview of randomized trials of intravenous heparin in patients with acute myocardial infarction treated with thrombolytic therapy.

Intravenous heparin is routinely given after thrombolytic therapy for patients with acute myocardial infarction in the United States and in some, but by no means all, other countries. Several trials have documented improved infarct-artery patency in patients treated with heparin; however, none was large enough individually to assess the effect of heparin on clinical outcomes. We performed a systematic overview of the 6 randomized controlled trials (1,735 patients) to summarize the available data concerning the risks and benefits of intravenous heparin versus no heparin after thrombolytic therapy. Mortality before hospital discharge was 5.1% for patients allocated to intravenous heparin compared with 5.6% for controls (relative risk reduction of 9%, odds ratio 0.91, 95% confidence interval 0.59 to 1.39). Similar rates of recurrent ischemia and reinfarction were observed among those allocated to heparin therapy or control. The rates of total stroke, intracranial hemorrhage, and severe bleeding were similar in patients allocated to heparin; however, the risk of any severity of bleeding was significantly higher (22.7% vs 16.2%; odds ratio 1.55, 95% confidence interval 1.21 to 1.98). There was no significant difference in the observed effects of heparin between patients receiving tissue-type plasminogen activator and those receiving streptokinase or anisoylated plasminogen streptokinase activator complex, or between patients who did and did not receive aspirin. The findings of this overview demonstrate that insufficient clinical outcome data are available to support or to refute the routine use of intravenous heparin therapy after thrombolysis. It is not known if these findings are due to lack of statistical power, inappropriate levels of anticoagulation, or lack of benefit of intravenous heparin. Large randomized studies of heparin (and of new antithrombotic regimens) are needed to establish the role of such therapy.

Effect of heparin on coronary arterial patency after thrombolysis with tissue plasminogen activator in acute myocardial infarction.

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

Adjunctive therapy in thrombolysis for acute myocardial infarction.

The value of prompt coronary reperfusion utilizing thrombolytic therapy during acute myocardial infarction has been well established. However, new data indicates that although rapid reperfusion is imperative, this positive effect may, in fact, be partially or totally negated if patency is not sustained and complete. The following manuscript discusses the role of adjunctive agents in thrombolysis that are essential in preventing coronary reocclusion. It is this important function that serves to prevent recurrent ischemia and reinfarction, thereby improving resultant left ventricular function. This, in turn, should have a positive effect on post-thrombolytic mortality. The data presented in this paper supports high dose, titrated intravenous heparin and aspirin as required adjunctive therapy to thrombolytic treatment in the setting of acute myocardial infarction.

An angiographic assessment of alteplase: double-bolus and front-loaded infusion regimens in myocardial infarction. DouBLE Study Investigators. Double Bolus Lysis Efficacy.

BACKGROUND: This study was designed to investigate the efficacy of alteplase double-bolus dosing compared with the front-loaded 90-minute infusion regimen in patients with acute myocardial infarction. Recent pilot studies have suggested that bolus dosing may provide improved efficacy in establishing early, complete, and sustained patency of the infarct-related artery in the thrombolytic treatment of acute myocardial infarction. METHODS AND RESULTS: In this multicenter, randomized, open-label trial, 461 patients with acute myocardial infarction received 100 mg alteplase as a front-loaded 90-minute infusion (15 mg bolus, then 50 mg over a 30-minute period, then 35 mg over a 60-minute period) or double bolus (two 50 mg bolus injections 30 minutes apart). All patients also received intravenous heparin and oral aspirin during and after alteplase treatment. The 90-minute angiographic patency rates were 74.5% in the double-bolus group and 81.4% in the infusion group (p = 0.08). Patency rates were also comparable for the two groups at 60 minutes (76.8% vs 77.5%) and 24 hours (95.5% vs 93.5%) after initiation of treatment. In-hospital mortality rates were 4.5% in the bolus group and 1.3% in the infusion group (p = 0.04); 30-day mortality rates were 4.5% and 1.7%, respectively (p = NS). The two-groups were comparable in frequency of all other adverse events. CONCLUSIONS: Double-bolus alteplase administration produced reperfusion rates comparable to front-loaded infusion, but in-hospital and 30-day mortality rates were higher in the double-bolus group. These findings are in agreement with those of the COBALT megatrial, which also reported a trend to higher mortality rates with double-bolus dosing.