For patients with CHD and CTD, we observed eight common correlations, namely age and mPAP (negative); PVR and RVSP (positive); mPAP and RVSP (positive); CD4+ and CD4+/CD8+ (positive); CD45+ and CD4+ (positive); CD4+ and CD3+ (positive); PVR and mPAP (positive); and age and PLT, which was positive in CHD patients but negative in CTD patients. The gene discussed is CD8A; the disease is coronary artery disorder.