Assessment of left ventricular diastolic dyssynchrony and its influencing factors early after acute myocardial infarction by SPECT gated myocardial perfusion imaging: an experimental study / 中华核医学与分子影像杂志

ABSTRACT

Objective:To evaluate the left ventricular diastolic dyssynchrony (LVDD) and its influencing factors early after acute myocardial infarction (AMI) using phase analysis of SPECT gated myocardial perfusion imaging (GMPI).Methods:Bama miniature swines ( n=16) were subjected to establish AMI models. GMPI was performed before and 1 d after AMI to obtain the extent of myocardial perfusion defect (Extent, %) and left ventricular systolic dyssynchrony (LVSD)/LVDD parameters, namely the phase histogram bandwidth (PBW) and phase standard deviation (PSD). Meanwhile, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), and the ratio of early to late peak mitral diastolic flow (E/A) were obtained by echocardiography. Independent-sample t test, paired t test and Pearson correlation analysis were used to analyze the data. Results:Sixteen AMI swines were successfully created. Compared to baseline, Extent, LVEDV and LVESV significantly increased on 1 d after AMI ( t values -11.14, -4.55, -6.12, all P<0.001), while LVEF and E/A significantly decreased ( t values 10.16, 2.18, P<0.001, P=0.046). GMPI showed that the LVDD parameters PBW and PSD increased significantly on 1 d after AMI when compared to those at baseline((142.25±72.06)° vs (33.06±8.98)°, (56.15±26.71)° vs (12.51±5.13)°; t values -6.11, -6.60, both P<0.001). There were significant differences between LVSD parameters and LVDD parameters (PBW (109.06±62.40)° vs (142.25±72.06)°, PSD (44.40±25.61)° vs (56.15±26.71)°; t values -2.73, -2.20, P values 0.016, 0.044). LVDD parameters PBW, PSD were negatively correlated with E/A after AMI ( r values -0.569, -0.566, P values 0.021, 0.022), and positively correlated with the Extent ( r values 0.717, 0.634, P values 0.002, 0.008). The phase analysis of SPECT GMPI to evaluate LVDD showed good intra-observer and inter-observe reproducibility (intraclass correlation coefficient (ICC) 0.953-0.984, all P<0.001). Conclusions:LVDD occurs early on 1 d after AMI, and can reflect left ventricular diastolic dysfunction. The Extent is correlated with LVDD significantly. Phase analysis of SPECT GMPI is an accurate method to evaluate LVDD and left ventricular diastolic function.