Interestingly, we found that when MPO was expressed in CAD ECFCs (n = 8, MPO gene expression = 5, no MPO gene expression = 3), it increased mROS production% (mean increase: 31.65 ± 11.81%, CI: 0.24% to 63.07%, p < 0.05) and mitochondrial mass% (mean increase: 26.44 ± 8.72%, CI: 3.95% to 48.93%, p < 0.05) whilst decreasing functional mitochondria% (mean decrease: 32.01 ± 6.31%, CI: −48.41% to −15.60%, p < 0.01) (Figure 3A–C). The gene discussed is MPO; the disease is coronary artery disorder.