Identification and transport of patients with acute myocardial infarction for thrombolytic therapy.

The concepts of acute, potentially reversible coronary artery thrombosis and myocardial salvage by early coronary thrombolysis using pharmacologic agents and/or percutaneous transluminal coronary angioplasty have evolved rapidly since 1980. Broad, general application of these methods awaited clear data on efficacy and safety of proposed treatment regimens, and in May 1987 streptokinase was recommended for approval by the Food and Drug Administration for intravenous use in patients with acute myocardial infarction. A second, more promising drug, recombinant tissue-type plasminogen activator, was approved by the FDA in November 1987. Thrombolysis is now accepted therapy for patients with acute myocardial infarction. Rapid identification of the patient with acute myocardial infarction plays an important role in treatment, because thrombolytic therapy is maximally effective if begun within four hours of the onset of symptoms. Care must be taken in selecting patients for treatment to ensure that an acute myocardial infarction is in evolution and that a medical condition predisposing to hemorrhage is not present. Cost of treatment and risk of complications must be considered before initiating therapy. In many patients, thrombolytic therapy can be considered only the first step in treatment, because of the relatively frequent occurrence of reocclusion and reinfarction after initial thrombolysis. If cardiac catheterization, angioplasty, and open heart surgery facilities are not readily available, transfer to a tertiary care center is indicated for high-risk patients, such as those with large anterior infarction, vacillating pain, or previous myocardial infarction. Transfer is safe if carried out promptly by critical care transport teams experienced in cardiac care.