目的 探讨血浆脑钠肽（BNP）及血清肌钙蛋白I（cTNI）含量改变在老年患者发生充血性心力衰竭时的临床意义。 方法 选择2010年7月－2012年8月住院的各种老年心脏病患者117例，根据纽约心功能分级分为4组（心功能Ⅰ级组、Ⅱ级组、Ⅲ级组、Ⅳ级组），分别检测血浆BNP、血清cTNI及心肌酶[肌酸磷酸激酶（CK）、肌酸磷酸激酶同工酶（CK-MB）]进行组间比较，同时与健康老年组进行对比。 结果 ① 老年慢性充血性心力衰竭各组（心功能Ⅱ～Ⅳ级）血浆BNP水平均高于健康对照组及心功能正常组（心功能Ⅰ级组）；且心功能Ⅳ级组BNP水平＞心功能Ⅲ级组＞心功能Ⅱ级组。各组之间比较差异有统计学意义，但心功能Ⅰ级组与健康对照组血浆BNP水平无明显差异。② 各组之间CK及CK-MB水平差异均无统计学意义。③ 充血性心力衰竭各组（心功能Ⅱ～Ⅳ级组血清cTNI水平均高于健康对照组及心功能正常组（心功能Ⅰ级组）；且心功能Ⅳ级组cTNI水平＞心功能Ⅲ级组＞心功能Ⅱ级组。各组之间比较差异有统计学意义，而心功能Ⅰ级组及健康对照组血清cTNI水平差异无统计学意义。 结论 血浆BNP水平及血清cTNI水平在老年患者发生心力衰竭时随心力衰竭程度加重而逐渐升高，两者均对慢性充血性心力衰竭的临床诊断具有重要参考意义。
Objective To identify clinical significance of high level cardiac troponin I （cTnI） in the early postoperative period of off-pump coronary artery bypass grafting （OPCAB） and its predictive value for early clinical outcomes. Methods A total of 240 patients undergoing isolated OPCAB in the Department of Cardiac Surgery of People’s Hospitalof Peking University during 2011 were recruited in the study. There were 164 males and 76 females with their age of 36-83（62.07±8.24） years. Serum cTnI levels in 4-6 hours and 12-18 hours after OPCAB were monitored. Influential factors and its predictive value for early clinical outcomes of OPCAB were analyzed. Binary logistic regression analysis，correlation analysis and receiver operating characteristic （ROC） curve were performed for statistic analysis. Results Serum cTnI level in 4-6 hours after OPCAB （TNI0） was 1.28±0.40 ng/ml，and serum cTnI level in 12-18 hours after OPCAB （TNI1） was 3.60±0.74 ng/ml. Binary logistic regression analysis revealed that graft number was significant influential factors of TNI0 （P=0.000） and TNI1 （P=0.010）. Serum cTnI level in 12-18 hours after OPCAB was significantly correlated with early clinicaloutcomes of OPCAB （P＜0.05），but the correlational relationship was not b （correlation coefficient＜0.5）. ROC curveanalysis showed that serum cTnI level in 12-18 h after OPCAB had higher predictive value for patient prognosis （P＜0.05）. Serum cTnI level higher than 1.49 ng/ml in 12-18 h after OPCAB had good predictive value for postoperative ECG changes，use of intra-aortic balloon pump （IABP） and in-hospital mortality. Conclusions Serum cTnI level increases in varying degrees in the early postoperative period of OPCAB. Together with ECG changes，serum cTnI level can be used for early diagnosis of perioperative myocardial infarction with significant predictive value for early clinical outcomes of OPCAB.
Objective To investigate the effect of polyethylene glycolbovine hemoglobin (PEG-bHb), which was used as an oxygen carrier in cardioplegic solution, on the protection of isolated rat hearts. Methods The hearts of 32 male SD rats were harvested and transferred to Langendorff circuit. They were divided into 4 groups according to cardiocplegia: St.Thomas group (group A), 1∶2 PEG-bHb group (group B), 1∶4 PEG-bHb group (group C) and 1∶8 PEG-bHb group (group D). After 20min balance period, hearts were perfused with cold (4℃) cardioplegic solutions, and preserved at 30℃ for 60min, then reperfused. Levels of cardiac troponin I (cTn I) and adenosine triphosphate(ATP) contant in coronary effuent were detected, and ultrastructures of myocardium were observed. Results After reperfusion, cTn I contant of group A were higher (F=52.955,Plt;0.05) and ATP contant were lower (F=68.757,Plt;0.05) than those in group B, group C and group D. Myocardial water contant were lower in group B and group C(F=3.048,Plt;0.05). Conclusion PEG-bHb in cardioplegic solutions can provide better myocardial protection during ischemia.
Objective To investigate whether single cycle ischemic preconditioning （IP） improves the myocardial preservation in patients undergoing cardiac valve replacement. Methods From August 2002 to April 2006, 85 patients who had chronic heart valve disease and required cardiac valve replacement were randomly divided into two groups. IP group, 47 allocated to receive IP and arrested with 4 C St. Thomas＇ Hospital cardioplegic solution during cardiopulmonary bypass（CPB）, preconditioning was accomplished by using single cycle of 2 minutes occlusion of aorta followed by 3 minutes of reperfusion before cross-clamping. Control group, 38 allocated to receive 4 C St. Thomas＇ Hospital cardioplegic solution alone. Myocardial protective effects were assessed by determinations of creatinine kinase-MB isoenzyme （CK-MB） and cardiac troponin I（cTnI）, ST-T changes, ventricular arrhythmias and other clinical data in ICU. Results Serum CK-MB and cTnI concentrations were increased postoperatively in two groups. At 24, 48 and 72h after operation, values of CK-MB in IP group was significantly lower than that in control group （P〈0.05）, cTnI at 24 and 48h after operation also less in IP group （P〈0.05）. The duration for patients needed for antiarrhythmic drugs in IP group was lower than that in control group （P〈0.05）. Compared with control group, fewer inotropic drugs were used in IP group. As a result, ICU stay time in IP group was shorter than that in control group （P〈0.05）. Conclusion IP enhances the myocardial protective effect when it was used with hypothermic hyper kalemic cardioplegic solution in patients undergoing cardiac valve replacement, IP significantly reduces the postoperative increase of CK-MB, cTnI and plessens the severity of postoperative ventricular arrhythmias.