风湿性心脏病合并肺动脉高压瓣膜置换病人血浆肾上腺髓质素的变化及作用

目的　观察风湿性心脏病(风心病)合并肺动脉高压病人瓣膜置换术前后血浆肾上腺髓质素(AM)、内皮素-1（ET-1）、一氧化氮(NO)及肺血流动力学的变化。方法　37例风心病病人手术前后采用放射免疫法测定血浆AM、ET-1浓度，采用测定血浆亚硝酸盐/硝酸盐含量来反映NO水平，采用Swan-Ganz浮导管测定肺血流动力学指标。结果　严重肺动脉高压组病人术前血浆AM、ET-1水平明显高于正常肺动脉压组(P＜0.05)；术后1周各组血浆AM水平都有不同程度的下降，而严重肺动脉高压组血浆ET-1水平无明显下降；术后严重肺动脉高压、肺动脉高压组血浆NO水平有一个降低及再恢复的过程；术前血浆AM/ET-1比值水平与肺血管阻力呈负相关(r=－0.503，P＜0.01)，术后48h血浆AM/ET-1比值与平均肺动脉压、肺血管阻力呈负相关（r=－0.524、－0.551，P＜0.05）。结论　AM在风心病肺动脉高压的形成和术后缓解过程中发挥了拮抗ET-1的作用，血浆AM/ET-1的比值与术后肺动脉高压的改善有关。

The changes of perioperative plasma level of adrenomedullin and its effects in rheumatic heart disease patients with pulmonary hypertension

Objective: To study the perioperative changes of plasma levels of adrenomedullin (AM), endothelin 1 (ET 1), nitric oxide (NO) concentration and pulmonary circulation in the rheumatic heart disease (RHD) patients with pulmonary hypertension. Methods: The plasma concentrations of AM and ET 1 were measured by radioimmunoassay in 37 RHD patients with pulmonary hypertension. The blood sample was taken from central vein. The plasma NO levels were measured as their metabolites NO 2/NO 3. The pulmonary hemodynamic variables were measured by right sided heart catheterization with Swan Ganz catheter. Results: Before operation, the plasma concentrations of AM and ET 1 in patients with severe pulmonary hypertension were significantly higher than those with normal pulmonary pressure (P<0.05). After surgery, the plasma concentrations of AM in all patients decreased to some degrees. However, the plasma concentrations of ET 1 in the patients with severe pulmonary hypertension were still as high as in preoperation. The plasma NO levels in the patients with pulmonary hypertension showed a continuos decrease after operation, then a slow rise going back to normal levels. The ratio of preoperative plasma levels of AM and ET 1 (AM/ET 1) was negatively correlated with pulmonary vascular resistance, and the ratio of AM/ET 1) at the 48th hour after operation was negatively correlated with mean pulmonary artery pressure and pulmonary vascular resistance. Conclusion: The plasma concentrations of AM are increased in RHD patients with pulmonary hypertension, which may help to attenuate action of increased ET 1 level and play an important role in regulated the perioperative pulmonary circulation.