Assessment of regional left ventricular function using gated radionuclide angiography.

A simple method for the assessment of regional left ventricular (LV) function using gated radionuclide angiography is described. The method divides the LV region of interest in the left anterior oblique view into quadrants using a count-weighted center point and a transparent overlay. The regional ejection fraction (EF) was determined at rest and during upright bicycle exercise for each of 3 quadrants identified as posterior, septal and apical. The study group consisted of 50 patients with chest pain. Nine of these patients had normal coronary arteries and 41 had significant coronary artery disease (CAD). Regional EF measurements were highly reproducible at rest and exercise in all regions. Regional EF values at rest were compared with the subjective assessment of wall motion on the contrast ventriculogram and were significantly lower in regions with abnormal wall motion. Regional EF increased with exercise in all patients with normal coronary arteries. In patients with CAD and normal regional wall motion at rest, the regional exercise response was significantly more sensitive (p = 0.004) than global exercise response and marginally more sensitive (p = 0.06) than the subjective assessment of exercise wall motion on visual radionuclide images in the diagnosis of CAD. These results suggest that the measurement of regional LV function may be useful in the noninvasive diagnosis of CAD.