Abstract
Funding Acknowledgements
Type of funding sources: None.
Introduction
Most 82Rubidium-(Rb)-Positron emission tomography (PET) studies for myocardial perfusion, dipyridamole was used as vasodilator. Less data is available for adenosine and regadenoson.
Purpose
Therefore, the aim was to evaluate the influence of adenosine and regadenoson on left ventricular ejection fraction (LVEF), myocardial blood flow (MBF) and hemodynamics in vasodilator 82Rb-PET.
Methods
Consecutive patients (n = 2299) with suspected or known coronary artery disease (CAD) undergoing 82Rb-PET were studied and compared according to CAD status and normal/abnormal PET (abnormal defined as summed stress score ≥4). Differences between stress and rest values (LVEF, MBF, hemodynamics) were calculated. The threshold of stress LVEF able to exclude a relevant ischemia (as defined by ≥10% myocardium ischemic based on SDS score) was assessed.
Results
Rest and stress LVEF differed significantly depending on CAD status and scan results. In patients with suspected CAD, rest/stress LVEF were 68 ± 12% and 73 ± 12% (p < 0.001), in patients with prior CAD 60 ± 14% and 63 ± 15% (p < 0.001). LVEF during stress increased 5 ± 6% in normal compared to 1 ± 8% in abnormal PET (p < 0.001). Global rest MBF (rMBF), stress MBF (sMBF) and myocardial flow reserve (sMBF/rMBF) were significantly higher in suspected CAD patients compared to prior CAD patients (1.3 ± 0.5, 3.3 ± 0.9, 2.6 ± 0.8 and 1.2 ± 0.4, 2.6 ± 0.8, 2.4 ± 0.8 ml/g/min, respectively, p < 0.001), and in normal versus abnormal scans, irrespective of CAD status (no CAD: 1.4 ± 0.5, 3.5 ± 0.8, 2.8 ± 0.8 and 1.2 ± 0.8, 2.5 ± 0.8, 2.2 ± 0.7; known CAD: 1.3 ± 0.4, 3.1 ± 0.8, 2.7 ± 0.8 and 1.1 ± 0.4, 2.3 ± 0.7, 2.2 ± 0.7 ml/g/min, respectively, p < 0.001). LVEF and hemodynamic values were similar for adenosine and regadenoson stress. Stress LVEF ≥70% excluded relevant ischemia with a negative predictive value (NPV) of 94% (CI 92-95%).
Conclusions
Rest/stress LVEF, LVEF reserve and MBF values are lower in abnormal compared with normal scans. Adenosine and regadenoson seem to have similar effect on stress LVEF, MBF and hemodynamics. A stress LVEF ≥70% has a high NPV to exclude relevant ischemia.
P3714The correlation between left ventricular ejection fraction by echocardiography and positron emission tomography
