These findings indicated that BPA significantly reduced BNP levels in inoperable CTEPH patients (standard mean difference = −0.7 pg/mL, 95% CI: [−0.88, −0.61], P = .000) with mild heterogeneity (I2 = 30.9%) (Figure 3C). This evidence concerns the gene NPPB and chronic thromboembolic pulmonary hypertension.