Relationship of quantitative parameters of myocardial perfusion SPECT and ventricular arrhythmia in patients receiving cardiac resynchronization therapy

Abstract

Lower LVEF, larger scar and/or more dyssynchrony assessed by MPS were related to the development of ventricular arrhythmia for patients with CRT, and further defibrillator implantation may be considered for these patients.

A perfect tool for comprehensive evaluation of myocardial perfusion and function: Stress PET imaging

“…In our previous SPECT studies, we had similar observations that significant correlation was noted between myocardial scar (expressed as area of resting myocardial perfusion defect) and phase SD in heart failure patients with cardiac resynchronization therapy (CRT). 11 In addition, we further demonstrated that myocardial scar interfered with the normal propagation of mechanical activation, resulting in more heterogeneous activation sequences and thus contributing to the development of ventricular arrhythmia. 12 Since the invention of the phase analysis technique from ECG-gated MPI with SPECT by Chen et al in 2005, 13 it has led this imaging modality to discover a ''New World'' in nuclear cardiology.…”

“…15,16 Our group further demonstrated that myocardial scar burden (area with activity less than 50% of maximal myocardial uptake), LVEF, and LV dyssynchrony as assessed by gated SPECT MPI were significantly correlated to the development of ventricular arrhythmia (ventricular tachycardia or ventricular fibrillation) in patients with heart failure who had received CRT. 11 As shown in Figure 1A, those (group A) with better ventricular systolic function (LVEF [ 29%), smaller infarcted myocardium (scar burden \ 23%), and less LV dyssynchrony (phase SD \ 50°) had significantly better survival than the others (group B) for the development of ventricular arrhythmia. The latter (group B) had a hazard ration of 5.16 (compared to group A).…”

Impact of cardiac reverse remodeling after cardiac resynchronization therapy assessed by myocardial perfusion imaging on ventricular arrhythmia

“…17 Episodes of VT and/or VF detected by the implanted device were validated by two electrophysiologists. 18,19 Electrocardiography (ECG) All patients received two intrinsic ECGs, one was performed before the CRT and the other was performed after transient turn-off of CRT for about 30 minutes before. Intrinsic QRS duration (iQRSd) was measured from the initial to the end of QRS wave.…”

Myocardial substrate after cardiac resynchronization therapy and the risk of ventricular arrhythmias

“…and dyssynchrony. 17 Although these risk prediction tools show great promise, they need to be prospectively validated in clinical studies.…”