Abstract： Objective To explore clinical outcomes of nitroglycerin perfusion via the aortic root before heart re-beating for patients undergoing heart valve replacement. Methods A total of 254 patients with valvular heart diseases underwent heart valve replacement in Beijing Anzhen Hospital from January 2008 to December 2011. According to whether or not they received nitroglycerin perfusion via the aortic root before heart re-beating during cardiopulmonary bypass （CPB）， all the 254 patients were randomly divided into two groups， the nitroglycerin group and the control group. There were 134 patients in the nitroglycerin group including 57 males and 77 females with their average age of 58.47±12.34 years. They received aortic root perfusion of 5 mg nitroglycerin diluted into 20 ml after full de-airing of the heart， and repeated aspiration was performed 8 to 10 times before heart re-beating during CPB. Aortic cross-clamp was released after the heart showed signs of automatic re-beating， and the aortic root was squeezed in high frequency by hand to make sure that the aorta was squeezed to close each time. In the control group， there were 120 patients including 64 males and 56 females with their average age of 61.85±11.97 years. Patients in the control group received routine procedures of CPB except nitroglycerin perfusion before heart re-beating. Automatic heart re-beating rate， CPB supporting time after heart re-beating， postoperative usage of inotropic drugs， mechanical ventilation time， perioperative morbidity and length of hospital stay were compared between the 2 groups， and patients were followed up and further evaluated. Results There was no in-hospital death. CPB supporting time after heart re-beating（12.32±9.76 min vs. 23.43±10.33 min， t=-1.233， P=0.000）， dopamine usage［3.45±2.33 μg/ （kg?min） vs. 5.67±3.12 μg/ （kg?min） ， t=-0.943 ， P=0.034］ and epinephrine usage ［0.026±0.013 μg/ （kg?min） vs. 0.056±0.021 μg/ （kg?min） ， t=-0.822 ， P=0.027］ of the nitroglycerin group were significantly shorter or lower than those of the control group. Automatic heart re-beating rate of the nitroglycerin group was significantly higher than that of the control group ［97.01% vs. 66.67 % ， χ 2 =-2.115 ， P=0.000］. A total of 121 patients in the nitroglycerin group were followed up for 2-36 months， and 13 patients were lost during follow-up. There was no death during follow-up. Conclusion For patients undergoing heart valve replacement， some myocardial protection strategies including nitroglycerin perfusion via the aortic root before heart re-beating， use of norepinephrine， and aortic root squeezing in high frequency by hand can significantly increase the automatic heart re-beating rate， shorten the CPB supporting time after heart re-beating， and improve postoperative clinical outcomes.
Abstract： Objective To observe myocardial protective effect of sevoflurane used in the whole process of cardiopulmonary bypass（CPB）. Methods A total of 150 patients older than 18 years who underwent cardiac surgery under CPB in Fu wai Hospital from January 2010 to November 2011 were enrolled in this double-blind and randomized controlled study. All the patients were randomly divided into three groups：Sevoflurane pretreatment group （Group A，n=50），whole-process Sevoflurane group （Group B，n=50），and whole-process intravenous anesthesia group （Group C，n=50）. Radial artery pressure and other hemodynamic parameters were continuously measured for all the patients. At following time points: CPB beginning （T1），aortic declamping （T2），3 hours after aortic declamping （T3），and 24 hours after aortic declamping （T4），serum concentrations of cardiac troponin I （cTnI） and other parameters were measured by enzyme-linked immunosorbent assay （ELISA）. Results There were 31 males and 19 females at age of 60.43±3.24 years in group A，28 males and 22 females at age of 59.88±4.12 years in group B，31 males and 19 females at age of 58.76±3.87 years. There was no statistical difference in mean arterial pressure （MAP），central venous pressure （CVP），pulmonary artery wedge pressure （PAWP） and heart rate （HR） at respective time points among the 3 groups （P＞0.05）. At T1 and T2，there was no statistical difference in cardiac index （CI） among the 3 groups （P＞0.05）. At T3，there was no statistical difference in CI between Group A and Group C（F=3.382，P=0.845），but CI of Group B was significantly higher than that of Group A and C（F=3.382，3.382； P=0.033，0.020）. At T4，CI of Group B was significantly higher than that of Group A and C （F=13.324，13.324； P=0.005，P=0.000），and CI of Group A was significantly higher than that of Group C （F=13.324，P=0.024）. At T1 and T2，there was no statistical difference in serum concentrations of creatinine kinase MB （CK-MB），cTnI，interleukin-6 （IL-6） and tumor necrosis factor alpha （TNF-α） among the 3 groups （P＞0.05）. At T3 and T4，serum concentrations of CK-MB，TNF-α，IL-6 and cTnI of Group C were significantly higher than those of Group A，and serum concentrations of CK-MB，TNF-α，IL-6 and cTnI of Group A were significantly higher than those of Group B （F=531.616，5.410，3.5813，3.160，1.126，4.702，7.819，5.424，all P=0.000）. Conclusion Sevoflurane used in the whole process of CPB has definite myocardial protective effect which is ber than that of Sevoflurane pretreatment.
Abstract: Objective To evaluate myocardial protection effect of different myocardial protective strategies for patients undergoing double valve replacement （DVR） . Methods From Jun. 2005 to Dec. 2005, 32 patients with predominant aortic valve stenosis undergoing DVR in Xinqiao Hospital were included in this study. These patients were randomly divided into four groups with 8 patients in each group： （1） antegrade perfusion group：Cold-blood cardioplegia was delivered antegradely through aortic root, and mitral valve replacement （MVR）was performed. Then cold-blood cardioplegia was delivered antegradely through left and right coronary ostia, and aortic valve replacement （AVR） was performed； （2）retrograde perfusion group：Cold-blood cardioplegia was delivered retrogradely and intermittently through coronary sinus, and DVR was performed； （3）antegrade＋retrograde perfusion group：The route of cold-blood cardioplegic infusion was antegrade during MVR procedure first and then retrograde during AVR procedure；and （4）beating heart group：Oxygenated blood from cardiopulmonary bypass machine was delivered retrogradely and continuously through coronary sinus, and DVR was performed with beating heart. Early clinical outcomes were observed. Serum cardiac troponin I （cTnI） was measured by enzyme-linked immunosorbent assay（ELISA）. Serum creatine kinase-MB （CK-MB） and myocardial lactic acid release rate were measured by Hitachi7150 Automatic Chemistry Analyzer. Myocardial mitochondria malondialdehyde （MDA） level was measured through thiobarbituric acid reagent species analysis. Results All the 32 patients survived their surgery and were discharged successfully. Myocardial lactic acid release rate at 80 min after aortic cross-clamping, serum cTnI and CK-MB on the first postoperative day, myocardial mitochondria MDA levels of beating heart group were 13.59%±6.27%,（1.17±0.25） ng/ml, （56.43±16.50） U/L and（2.18±1.23） nmol/（ng.prot）respectively, all significantly lower than those of retrograde perfusion group ［（33.49%±8.29%, （1.82±0.58 ）ng/ml, （78.31±21.27） U/L （5.07±2.35） nmol/（ng.prot），P＜0.05］ and antegrade＋retrograde perfusion group［20.87%±7.22%, （1.49±0.23） ng/ml,（66.67±19.13） U/L,（4.34±1.73） nmol/（ng.prot），P＜0.05］, but not statistically different from those of antegrade perfusion group ［18.83%±5.97%, （1.41±0.32） ng/ml, （63.21±37.52） U/L, （3.46±1.62） nmol/ （ng.prot），P＞0.05］. Conclusion All the four myocardial protective strategies are effective myocardial protection methods for DVR patients. Continuous retrograde perfusion with beating heart and intermittent antegrade perfusion can provide better myocardial protection, and therefore are preferred for DVR patients. The combination of antegrade and retrograde perfusion is easy to administer and does not negatively influence surgical procedures. Retrograde perfusion is also effective as it takes only a short time.