Use of phase analysis of gated SPECT perfusion imaging to quantify dyssynchrony in patients with mild-to-moderate left ventricular dysfunction

作者：Atchley Allen E; Trimble Mark A; Samad Zainab; Shaw Linda K; Pagnanelli Robert; Chen Ji; Garcia Ernest V; Iskandrian Ami E; Velazquez Eric J; Borges Neto Salvador^*

来源：Journal of Nuclear Cardiology, 2009, 16(6): 888-894.

DOI：10.1007/s12350-009-9136-3

• Mechanical dyssynchrony
• cardiac resynchronization therapy
• heart failure
• SPECT imaging

CRT has been shown to be beneficial in the majority of patients with NYHA class III-IV symptoms, prolonged QRS duration, and an EF a parts per thousand currency sign35%. The use of imaging modalities to quantify dyssynchrony may help identify patients who may benefit from CRT, but do not meet current selection criteria. We hypothesize that patients with mild-to-moderate LV dysfunction have significant degrees of mechanical dyssynchrony.
We compared phase analysis measures of mechanical dyssynchrony from gated SPECT imaging in patients with mild-to-moderate LV dysEF 35-50%, n = 93), with patients with severe LV dysEF a parts per thousand currency sign 35%, n = 167), and with normal controls (EF a parts per thousand yen 55%, n = 75). Furthermore, we evaluated the relationships between QRS duration and dyssynchrony and determined the prevalence of dyssynchrony in patients with mild-moderate LV dysfunction.
Patients with mild-moderate LV dysfunction have more dyssynchrony than normal controls (phase SD 37.7A degrees vs 8.8A degrees, P < .001 and bandwidth 113.5A degrees vs 28.7A degrees, P < .001), but less dyssynchrony than patients with severe LV dysphase SD 37.7A degrees vs 52.0A degrees, P < .001 and bandwidth 113.5A degrees vs 158.2A degrees, P < .001). In the cohort of patients with LV EF 35-50%, there were only weak correlations between QRS duration and dyssynchrony (phase SD, r = 0.28 and bandwidth, r = 0.20). There were 73 patients with LVEF 35-50% and QRS duration < 120 milliseconds of which 21 (28.8%) had mechanical dyssynchrony. Overall, 37% of patients with mild-to-moderate LV dysfunction had significant degrees of mechanical dyssynchrony.
This is the largest reported study evaluating mechanical dyssynchrony in patients with mild-moderate LV dysfunction using phase analysis of gated SPECT imaging. In this study, approximately one-third of patients with mild-to-moderate LV dysfunction had significant LV mechanical dyssynchrony. With further study, phase analysis of gated SPECT imaging may help improve patient selection for CRT.

• 出版日期2009-12