Plasma BNP levels in normal subjects are about 0–20 pg/mL and plasma BNP levels are increased in left ventricular hypertrophy [3], myocardial infarction [4,5], coronary artery disease [6], pulmonary hypertension [7], and heart failure [8,9], according to the severity of the disease. This evidence concerns the gene NPPB and pulmonary arterial hypertension.