Comparison of gated N-13 ammonia PET and gated Tc-99m sestamibi SPECT for quantitative analysis of global and regional left ventricular function.

BACKGROUND: The aim of this study was to compare global and regional left ventricular function in patients with coronary artery disease (CAD), obtained by use of Cedars-Sinai quantitative gated single photon emission computed tomography (QGS), for gated nitrogen 13 ammonia (NH(3)) positron emission tomography (PET) and technetium 99m sestamibi (MIBI) single photon emission computed tomography (SPECT).

METHODS AND RESULTS: Fifty-one patients with CAD underwent gated N-13 NH(3) PET and gated MIBI SPECT. The end-diastolic volume, end-systolic volume, and ejection fraction were calculated by use of QGS. The quantitative regional wall motion (WM) and wall thickening (WT) scores for 20 segments in the myocardium were also measured by QGS. The end-diastolic volume, end-systolic volume, and ejection fraction measured by N-13 NH(3) PET showed highly significant correlation with those measured by MIBI SPECT (r = 0.97, r = 0.97, and r = 0.84, respectively). The mean correlation of WM and WT on an individual patient basis between N-13 NH(3) PET and MIBI SPECT was 0.81 and 0.84, respectively. The circumferential variation of WM and WT in 20 segments showed a similar pattern with N-13 NH(3) PET and MIBI SPECT.

CONCLUSION: Gated N-13 NH(3) PET combined with QGS provides information on both global and regional left ventricular function comparable to that obtained by gated Tc-99m perfusion myocardial SPECT in CAD patients.