Role of phase parameters on gated myocardial perfusion SPECT 3 months after coronary bypass graft surgery (CABG) for the prediction of delayed reverse remodeling in patients with patent grafts and perfusion improvement after CABG

Abstract

Purpose:

Phase analysis using gated myocardial perfusion single photon emission computed tomography (GMPS) is a tool used to assess left ventricular (LV) dyssynchrony. We attempted to investigate the role of LV dyssynchrony assessed by GMPS using phase analysis for the prediction of LV function after coronary artery bypass surgery (CABG).

Methods:

A total of 40 patients who received off pump CABG with patent graft 1 yr after CABG were enrolled retrospectively. All patients underwent GMPS before and 3 mo and 1 yr after CABG. Using the Emori Cardiac Toolbox, both phase histogram bandwidth (PBW) and phase standard deviation (PSD) derived by phase analysis were used for the analysis, in addition to the conventional parameter. For the evaluation of heart function, transthoracic echocardiography was also performed.

Results:

One year after CABG, 16 out of 40 patients exhibited reverse remodeling. All of these patients showed significant improvement in perfusion (paired t-test, p<0.05) 3 mo after CABG. Using stepwise logistic regression with forward selection, PBW 3 mo after CABG was able to predict reverse remodeling 1 yr after CABG (odds ratio [OR] 1.03, p<0.05). Using receiver operating characteristic curve analysis, PBW 3 mo after CABG had the largest area under the curve to detect reverse remodeling with a cutoff value of 82 (sensitivity 0.94, specificity 0.58, p<0.001).

Conclusion:

In the prediction of reverse remodeling, early postoperative LV dyssynchrony had predictive value.