Risk stratification by nuclear imaging
Nuclear imaging of the heart is useful in risk stratification. A normal perfusion image after adequate stress would mean a very low cardiac event rate of less than one percent. Similarly, small fixed defect with normal global left ventricular function also indicates good prognosis.
The high risk subsets are those with reversible defects in more than one vascular territory, those with perfusion defects in left anterior descending (LAD) coronary artery territory, as it is the most important coronary artery, post-stress left ventricular dysfunction with left ventricular dilatation, abnormal wall motion, decreased left ventricular ejection fraction (LVEF) or increased lung uptake indicating pulmonary congestion as a result of left ventricular dysfunction.