NPPB and coronary artery disorder: Biochemical markers used to diagnose CHD include NT-proBNP, a hormone released by the atria and ventricles in response to stretching from volume or pressure overload, 5-HIAA, a serotonin metabolite and chromogranin A, a less sensitive and specific protein secreted by neuroendocrine tumors, can be elevated in the serum of patients with CHD and rising levels correlate well with disease progression [2, 4, 17, 20].