Should all patients undergo cardiac catheterization after a myocardial infarction?

Between one half and two thirds of patients who survive an acute myocardial infarction (AMI) may be at low risk for future complications and hence can be managed with medical therapy. However, the remaining patients are prone to future complications, which by and large occur within the subsequent 3 months and include cardiac death, recurrent AMI, unstable angina, and congestive heart failure. Current available methods for risk stratification include a good clinical evaluation, rest and stress electrocardiograms (preferentially combined with radionuclide imaging), and possibly two-dimensional stress echocardiography. In patients unable to exercise, pharmacologic perfusion scintigraphy affords a powerful means to identify high-risk patients. Patients deemed to be at high risk should be referred for cardiac catheterization and myocardial revascularization. The practice of performing routine cardiac catheterization after an AMI has led to an over use of resources in the United States. Such a practice is not based on any scientific evidence of enhanced benefit. In fact, in other Western world countries where only selected patients are referred for cardiac catheterization, patient survival appears to be similar to that in the United States. In conclusion, most patients after AMI, whether treated with thrombolytic therapy or not, can be managed conservatively and risk stratified on the basis of noninvasive testing, after which patients deemed to be at high risk should undergo invasive evaluation.