Do stress echocardiography and myocardial perfusion imaging have the same ability to identify the low-risk patient with known or suspected coronary artery disease?

Although both stress myocardial perfusion imaging and echocardiography may have significant prognostic value, the annual death/myocardial infarction rate appears to be much higher in patients with a negative stress echocardiogram. This may greatly limit its ability to act as a "gatekeeper" for additional invasive and interventional procedures.