Assessment of myocardial washout of Tc-99m-sestamibi in patients with chronic heart failure: Comparison with normal control

Background: In contrast to (TlCl)-Tl-201, Te-99m-sestamibi shows very slow myocardial clearance after its initial myocardial uptake. In the present study, myocardial washout of Te-99m-sestamibi was calculated in patients with non-ischemic chronic heart failure (CHF) and compared with biventricular parameters obtained from first-pass and ECG-gated myocardial perfusion SPECT data. Methods and Results: After administration of Tc-99m-sestamibi, 25 patients with CHF and 8 normal controls (NC) were examined by ECG-gated myocardial perfusion SPECT and planar data acquisition in the early and delayed (interval of 3 hours) phase. Left ventricular ejection fraction (LVEF, %), peak filling rate (PFR, sec(-1)), end-diastolic volume (LVEDV, ml) and end-systolic volume (LVESV, ml) were automatically calculated from the ECG-gated SPECT data. Myocardial washout rates over 3 hours were calculated from the early and delayed planar images. Myocardial washout rates in the CHF group (39.6 +/- 5.2%) were significantly higher than those in the NC group (31.2 +/- 5.5%, p < 0.01). The myocardial washout rates for the 33 subjects showed significant correlations with LVEF (r = -0.61, p < 0.001), PFR (r = -0.47, p < 0.01), LVEDV (r = 0.45, p < 0.01) and LVESV (r = 0.48, p < 0.01). Conclusion: The myocardial washout rate of Tc-99m-sestamibi is considered to be a novel marker for the diagnosis of myocardial damage in patients with chronic heart failure.