Left ventricular dyssynchrony assessment by phase analysis from gated PET-FDG scans

Abstract

Accurate LV dyssynchrony assessment by phase analysis of gated PET-FDG scans is feasible, allowing assessing myocardial viability and severe LV dyssynchrony in one scan.

Effect of stress testing on left ventricular mechanical synchrony by phase analysis of gated positron emission tomography in patients with normal myocardial perfusion

“…While most of the literature has been exclusively performed with gated SPECT, there is growing interest in using gated PET [8] which offers better image quality and information on viability among other factors. It is important to decide which gated images to use to derive dyssynchrony indices (stress versus rest), at least in patients with normal MPI.…”

“…The 4DM software has not been validated in gated PET studies, but the analysis algorithm was extrapolated from gated SPECT studies. However, a recent paper with a small number of patients showed gated PET images yielded similar dyssynchrony indices to SPECT for patients who had both studies using the same algorithm of the Emory Cardiac Toolbox (ECTb) (R00.88) [8], and the 4DM software has also been validated against the ECTb [10]. In addition, there was a lack of an independent and gold standard reference for mechanical dyssynchrony.…”

“…The method depends on extracting count distribution from each slice of the left ventricular (LV) short axis data set and submitting it to a Fourier transform to generate a phase distribution [7]. Most of the studies have been done on gated single photon emission computed tomography (SPECT) studies, and recently limited data have become available with positron emission tomography (PET) [8]. A recent study has shown that the dyssynchrony indices derived from low tracer dose rest SPECT images are significantly higher than those obtained from high tracer dose stress images [9].…”

Relationships between left ventricular asynchrony and myocardial blood flow

“…26 BW is expressed in units of degrees, such that a full 360°spans the R-R interval, an approach that has been applied both to SPECT and PET data. 27 Previous studies using 82 Rb PET established gender-specific normal limits for rest BW (males: 50.8°± 18.7°, females: 44.4°± 44.9°) and stress BW (males: 38.1°± 13.3°, females: 32.0°± 13.5°). 13 We categorized severity of asynchrony as follows:…”

The role of PET quantification in cardiovascular imaging

“…The functional measurements from PET may also include phase and dyssynchrony analysis. Although these techniques have not been extensively validated with PET, measurements of histogram bandwidth and phase standard deviation from 15 O-water and 18 FDG PET scans, were found to be very well correlated with SPECT (16). Recently, in the analysis of 486 patients, left ventricular mechanical dyssynchrony was found to be an independent predictor of all-cause mortality in ischemic cardiomyopathy (17).…”