Abstract
BACKGROUND: This study aimed to evaluate the impact of Enhanced External Counterpulsation (EECP) therapy on myocardial blood flow (MBF) during stress and rest conditions, as well as coronary flow reserve (CFR). These parameters were assessed using non-invasive oxygen-15-labeled water ([(15)O]H(2)O) positron emission tomography/computed tomography (PET/CT) myocardial perfusion imaging (MPI). METHODS: Seven patients (six male, mean age 61.67 ± 9.33 years) with coronary artery disease completed 35 sessions of EECP therapy. All patients underwent [(15)O]H(2)O PET/CT MPI during rest and adenosine-induced stress conditions before and after EECP treatment, within a one-month period. MBF and CFR were measured, and a paired t-test was used to evaluate the significance of EECP's effects (p < 0.05). RESULTS: In a per-patient analysis, one patient had a normal [(15)O] H(2)O PET/CT MPI study, while six had abnormal scans at pre-EECP, with no changes post-EECP. However, significant increases in stress MBF were observed per vascular territories (p = 0.023) and within the 17-segment model (p = 0.002) following EECP. Subgroup analysis showed a significant rise in stress MBF in segments with initially low stress MBF (p = 0.002) and in rest MBF in segments with normal pre-EECP stress MBF (p = 0.001). CFR increased significantly in segments with initially abnormal CFR (p = 0.0003) and decreased in segments with normal CFR (p = 0.007). CONCLUSION: In our small study group, EECP significantly improved MBF and CFR, particularly in stress-induced regions with significant CAD, as confirmed by [(15)O]H(2)O PET/CT MPI.