Comparison of left ventricle mechanical dyssynchrony parameters in ischemic and non-ischemic patients using 13N-NH3 PET/CT

Angelica Mazzoletti,Domenico Albano,Francesco Bertagna,Claudio Tinoco Mesquita,Raffaele Giubbini

doi:10.1007/s12350-020-02466-w

Abstract

Background-AimThe relationship between perfusion pattern and stress-induced changes in Left Ventricular Mechanical Dyssynchrony (LVMD) has been previously described with controversial results using stress-rest perfusion imaging studies. The aim of this study was to assess the relationship between perfusion pattern and stress-induced changes in LVMD usingo regadenoson/rest13N-NH3 PET/CT. MethodsThere were 74 patients who underwent stress-rest 13N-NH PET/CT from January 2014 to October 2018 excluding patients with left bundle branch block, ventricular pacing and myocardial necrosis. The patients were divided into those with reversible perfusion defects at stress (Ischemic group, n = 18) and patients without reversible perfusion defects (non-ischemic group, n = 56). The LVMD parameters included: phase standard deviation (PSD) and phase histogram bandwidth (PHB), after stress and at rest. The ΔPSD (post-stressPSD-restPSD) and ΔPHB (post-stressPHB—restPHB) were calculated to measure stress-induced changes in LVMD. ResultsThere were no significant differences in LVMD parameters between post-stress and at rest in both groups. The PSD post-stress, ΔPSD and PHB post-stress were significantly higher in the ischemic group. ConclusionsUsing a vasodilator as a stress, the PSD and PHB post-stress and ΔPSD were significantly higher in the ischemic patients than the non-ischemic group, while there were no significant differences in each cohort between stress and rest indices.

Highlights

Left ventricular mechanical dyssynchrony (LVMD) is defined as the differences in the timing of onset of contraction between the different myocardial segments and it may have prognostic value for risk stratification.[1,2] LVMD by phase analysis of gated myocardial perfusion imaging (MPI) has emerged as a robust, automated, and reproducible technique to quantify mechanical dispersion.3 13N-ammonia (13N-NH3) may be used in PET/TC imaging and allows quantification of Mazzoletti et al Comparison of left ventricle mechanical dyssynchrony parametersJournal of Nuclear CardiologyÒ coronary flow reserve (CFR), myocardial blood flow (MBF) LV perfusion, wall motion, LV function and LVMD in patients with Coronary artery disease (CAD)
The aim of this study was to evaluate the relationship between perfusion pattern and stress-induced changes in LVMD using 13N-NH3 PET/CT after regadenoson stress and at rest
The CFR was calculated as the ratio of hyperemic to resting MBF; CFR e’’ 2.5 was considered as normal

Summary

Introduction

Left ventricular mechanical dyssynchrony (LVMD) is defined as the differences in the timing of onset of contraction between the different myocardial segments and it may have prognostic value for risk stratification.[1,2] LVMD by phase analysis of gated myocardial perfusion imaging (MPI) has emerged as a robust, automated, and reproducible technique to quantify mechanical dispersion.3 13N-ammonia (13N-NH3) may be used in PET/TC imaging and allows quantification of Mazzoletti et al Comparison of left ventricle mechanical dyssynchrony parametersJournal of Nuclear CardiologyÒ coronary flow reserve (CFR), myocardial blood flow (MBF) LV perfusion, wall motion, LV function and LVMD in patients with Coronary artery disease (CAD). Previous studies[4,5,6] with different radiotracers such as Rubidium-82 and 99mTc-sestamibi, demonstrated that stress-induced ischemia causes dyssynchronous contraction in the ischemic region, leading to worsening of LVMD, but no previous study has examined the use of 13N-NH3. The aim of this study was to evaluate the relationship between perfusion pattern and stress-induced changes in LVMD using 13N-NH3 PET/CT after regadenoson stress and at rest. Aim. The relationship between perfusion pattern and stress-induced changes in Left Ventricular Mechanical Dyssynchrony (LVMD) has been previously described with controversial results using stress-rest perfusion imaging studies. The aim of this study was to assess the relationship between perfusion pattern and stress-induced changes in LVMD usingo regadenoson/rest13N-NH3 PET/CT

Objectives

Methods

Results

Conclusion