Continuous measurement of subarachnoid pressure in the severely asphyxiated newborn.

1818 Objectives To determine the correlation between the noninvasive assessment of coronary flow reserve (CFR), the amount of coronary artery calcium, and myocardial ischemia in patients (pts) with known and or suspected ischemic coronary artery disease (CAD). Methods Fifty-five pts (29 male), mean age 69± 4 year old referred for chest pain and/or shortness of breath, underwent rest and hyperemia (32 dypiridamole,23 regadenoson) (13)N-ammonia non contrast-enhanced standard cardiac PET/CT. Regional and per coronary vessel MBF was assessed in absolute units with (13)N-ammonia PET/CT. Total and per coronary vessel calcium score (CAC) was assessed by Agatston score. Qualitative perfusion was defined by a 17 LV segment model using a 5 point scale (with 0 = normal and 4 = severe defect). Ischemia was defined as summed stress score (SSS) ≥ 4 plus summed differential score (SDS) ≥ 2 and scar was defined as SSS ≥ 4 and SDS ≤ 2. Stress LV EF and LV volumes were also determined. Results Thirty five pts with a SSS <4 (LVEF 64+-8) had a total CAC of 480 HU (Group 1). Of those 20 pats with a SSS ≥ 4, 14 have a SDS ≥ 2 (LVEF 43 ±10) and a total CAC 2019 (Group 2), while 6 pts have a SDS ≤ 2 (LVEF 30 % ± 18) and total CAC 1,012 (group 3). Hyperemic MBF was significantly higher in Group 1 (2.39 ± 0.7ml/min /g) compared to Group 3 (1.38 ± 0.50 ml/min/g, p < 0.05), and a trend was established with group 2 (2.27 ± 0.64 ml/min/g). The same correlation was noted for CFR (2.59 ± 0.70; 2.20 ±0.6; 1.91 ± 0.6) for Groups 1 to 3, respectively. Conclusions This study suggests a correlation trend between the total CAC and hyperemic MBF, though, it depicts a variable relationship with the presence of myocardial ischemia. Conversely, ,as expected, hyperemic MBF is blunted in those patients with severe left ventricular dysfunction and extensive CAC