ObjectiveTo explore the curative effects of Puerarin Injection associated with Irbesartan on decompensated chronic cor pulmonale heart failure. MethodsA total of 168 cases conforming to the diagnostic standards were randomized into control group (92 cases) and therapy group (76 cases). In the control group: Based on the results of sputum and X-ray, broad-spectrum antibiotics were firstly selected and used for 3 days after admission. Then sensitive antibiotics were selected according to the results of sputum culture and drug sensitivity test. Medicine for relieving cough and asthma, and apophlegmatisant were used routinely. Patients with heart failure were treated with Digoxin or diuresis. In addition to the above treatments, the therapeutic group were treated with Puerarin Injection 600mg and Irbesartan 75mg once a day. The two groups were both treated for 20 days. Results①The incipient slope, 0.8 slope, 0.5 slope and the minimal surplus were all significantly changed (P＜0.01) in therapeutic group after the treatment. There were significant difference in the incipient slope, 0.8 slope, 0.5 slope and the minimal surplus before and after treatment both in the control group and therapeutic group. ②The plasma viscosity and blood viscosity decreased observably (P＜0.01) after the treatment in the therapeutic group, and more obviously than that in the control group (P＜0.01). ③The arterial oxygen pressure (PaO2) and arterial oxygen saturation (SaO2) in the therapeutic group were enhanced more prominently than that of the control group (P＜0.01). ④The mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) decreased obviously in the therapeutic group after the treatment, and more observably than those in the control group (P＜0.01). ⑤The cardiac output and cardiac index were improved prominently in the therapeutic group after the treatment, and more obviously than that of the control group (P＜0.01). ⑥The heart functional capacity (NYHA) improved significantly after the treatment both in the control group and the therapeutic group (P＜0.05). ConclusionsPuerarin Injection and Irbesartan could remarkablely change the erytlu'ocyte deformabifity, improve the hemorheology, lower pulmonary hypertension, and improve the cardiac function and the clinical efficacy in decompensation stage.