The rapid growth of cardiac catheterization has raised questions about the availability of less costly, "noninvasive" tests such as cardiac scintigraphy and echocardiography. To assess their availability and rates of use, we surveyed 3,778 non-federal short-term U.S. hospitals in June, 1983. Overall, 2,605 hospitals (69%) offered 201Tl myocardial perfusion scans, 2,580 (68%) 99mTc equilibrium gated blood pool scans, and 2,483 (67%) cardiac shunt scans; 1,679 hospitals (44%) offered M-mode and/or 2-dimensional echocardiography, and 768 (20%) pulsed Doppler echocardiography. Volumes of procedures varied enormously among hospitals capable of performing them. High volumes of both scintigraphy and echocardiography were performed in a small number of hospitals. Larger, voluntary, and teaching hospitals performed higher volumes of both procedures. Despite widespread availability of these "noninvasive" technologies, high volumes of both cardiac scintigraphy and echocardiography procedures are concentrated in a small number of U.S. hospitals.