<prompt> Answer this question truthfullyWhat are the guidelines to follow for performing echocardiography?  <response>: <reason> Class I Assessment of infarct size andor extent of jeopardized myocardium. In-hospital assessment of ventricular function when the results are used to guide therapy. In-hospital or early postdischarge assessment of the presenceextent of inducible ischemia whenever baseline abnormalities are expected to compromise electrocardiographic interpretation. Assessment of myocardial viability when required to define potential efficacy of revascularization. Class IIa In-hospital or early postdischarge assessment of the presenceextent of inducible ischemia in the absence of baseline abnormalities expected to compromise ECG interpretation. Re-evaluation of ventricular function during recovery when results are used to guide therapy. Assessment of ventricular function after revascularization. Class IIb Assessment of late prognosis greater than or equal to 2 years after acute myocardial infarction. Class III Routine re-evaluation in the absence of any change in clinical status. 