Reproducibility of diastolic function parameters in repeated ECG-gated SPECT myocardial perfusion imaging and echocardiography.

OBJECTIVE

To study the reproducibility of diastolic function parameters from myocardial perfusion imaging (MPI) using ECG-gated single photon emission computed tomography (SPECT), and echocardiography in repeated imaging.

METHODS

We studied the reproducibility of MPI diastolic function parameters peak-filling rate (PFR) and time to peak filling (TTPF) as well as echocardiographic parameters E/A, E/e', and E-wave deceleration time (DT). The study population consisted of 21 patients who underwent routine MPI with repeated rest acquisition and echocardiography. In a test-retest setting, appropriate diastolic measures were successfully obtained using SPECT in 20 patients, with E/A measured in 18, E/e' in 17, and DT in 16 patients.

RESULTS

We found that PFR was well reproducible with the intraclass correlation coefficient (ICC) 0.887, and coefficient of variation (CV%) 10.5. However, TTPF was poorly reproducible (ICC 0.012, and CV% 17.5). E/A was highly reproducible (ICC 0.963, and CV% 12.5). Decent reproducibility was observed for E/e' (ICC 0.809, and CV% 18.6) and DT (ICC 0.833, and CV% 12.0). We further studied the correlation between these parameters. PFR (EDV/s) had negative correlation with DT (r = -0.538, p = 0.039) and E/A had positive with E/é (r = 0.689, p = 0.002). No other significant correlations were observed (p > 0.05 for all). We also examined how parameters classified patients as normal or abnormal regarding the diastolic function. E/A and E/e´, as well as E/A and PFR showed similar classifications in 88% of cases, with a Kappa value of 0.433, p = 0.074 for both.

CONCLUSIONS

PFR obtained from repeated SPECT studies, along with the E/A ratio, is highly reproducible.