Many factors drive increased use.
Picard
Michael H
MH
D002309:Cardiology / Q000639:trends; D002318:Cardiovascular Diseases / Q000000981:diagnostic imaging; D004452:Echocardiography / Q000191:economics* / Q000706:statistics & numerical data*; D006801:Humans; D006278:Medicare / Q000191:economics*; D010818:Practice Patterns, Physicians' / Q000191:economics; D014481:United States