In patients with microvascular dysfunction and ischemia and no obstructive coronary arteries (INOCA) who underwent positron emission tomography, those who had CRP > 3 mg/L had a more severe impairment of coronary flow reserve (2.14 ± 0.33 vs. 3.16 ± 0.76; p = 0.001); furthermore, a negative correlation between CRP levels and coronary flow reserve (R = −0.49, p = 0.02) was shown [63]. This evidence concerns the gene CRP and ischemia.