[Evaluation of cardiac function by radioisotope angiography]

Cardiac function can be assessed with noninvasive radionuclide technique. Radioisotope angiography can be performed either using equilibrium acquisition or first pass technique. The most commonly generated measurements are as follows; 1) chamber-to-chamber transit time, 2) cardiac output, 3) left-to-right shunt ratio, 4) left and right ventricular ejection fractions, 5) left ventricular end-diastolic and end-systolic volumes, 6) regional wall motion, 7) peak ejection rate, and 8) peak filling rate. The ejection fraction, the systolic function and the diastolic function are calculated from ventricular volume curves. The left ventricular volume can be determined by two approaches, the geometric method using the left ventricular image to calculate the area and length of the chamber, and the count-based method. Generally, left ventricular wall motion is observed in right anterior oblique(RAO) view for the first pass method and the left anterior oblique(LAO) view for the equilibrium method. On the other hand, three dimensional multigated imaging was superior in allowing evaluation of left ventricular wall motion in all directions and in assessment of the left ventricular function. Three dimensional multigated imaging is very useful for observation of both left ventricular wall motion and left ventricular function in patients with ischemic heart disease, because it is a noninvasive examination. The quantitative gated myocardial SPECT(QGS) was considered to be useful for assessment of left ventricular function and myocardial perfusion.