Pulmonary oligemia maneuver can alleviate pulmonary artery injury during pulmonary thromboendarterectomy procedure / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pulmonary thromboendarterectomy (PTE) has evolved as a treatment of choice for chronic thromboembolic pulmonary hypertension (CTEPH). This study aimed to characterize if pulmonary oligemia maneuver (POM) can alleviate pulmonary artery injury during PTE procedure.</p><p><b>METHODS</b>A total of 112 cases of CTEPH admitted to Beijing Anzhen Hospital from March 2002 to August 2011 received PTE procedure. They were retrospectively classified as non-POM group (group A, n = 55) or POM group (group B, n = 57). Members from group B received POM during rewarming period, whereas members from group A did not.</p><p><b>RESULTS</b>There were three (5.45%) early deaths in group A, no death in group B (0) (Fisher's exact test, P = 0.118). Six patients in group A needed extracorporeal membrane oxygenation (ECMO) as life support after the PTE procedure, no patients in group B needed ECMO (Fisher's exact test, P = 0.013). The patients in group B had a shorter intubation and ICU stay, lower mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR), higher partial pressure of oxygen in artery (PaO2) and arterial oxygen saturation (SaO2) and less medical expenditure than patients in group A. With a mean follow-up time of (58.3 ± 30.6) months, two patients in group A and one patient in group B died. The difference of the actuarial survival after the procedure between the two groups did not reach statistical significance. Three months post the PTE procedure, the difference of residual occluded pulmonary segment between the two groups did not reach statistical significance (P = 0.393).</p><p><b>CONCLUSION</b>POM can alleviate pulmonary artery injury, shorten ICU stay and intubation time, and lower down the rate of ECMO after PTE procedure.</p>

Application of intraoperative arterial pressure-based cardiac output monitoring for patients undergoing coronary artery bypass grafting surgery / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>For patients undergoing off-pump coronary artery bypass grafting (OPCABG), it is important to establish a hemodynamic monitoring system to obtain powerful parameters for better intraoperative treatment. This study aimed to observe the clinical feasibility of arterial pressure-based cardiac output (APCO) for cardiac output (CO) monitoring and to evaluate the correlation between APCO and pulmonary artery catheter (PAC) for CO measurement for patients undergoing OPCABG intraoperatively.</p><p><b>METHODS</b>Fifty patients of American Society of Anaesthesiologists (ASA) classification II-III, undergoing elective OPCABG at Beijing Anzhen Hospital were randomly enrolled into this study. All patients were assigned to CO monitoring by PAC and APCO simultaneously. Patients with pacemaker, severe valvular heart disease, left ventricular ejection fraction (EF) < 40%, cardiac arrhythmias, peripheral vascular disease, application of intra-aortic balloon pump (IABP) and emergent diversion to cardiac pulmonary bypass were excluded. The radial artery waveform was analyzed to estimate the stroke volume (SV) and heart rate (HR) continuously. CO was calculated as SV ' HR; other derived parameters were cardiac index (CI), stroke volume index (SVI), systemic vascular resistance (SVR), and systemic vascular resistance index (SVRI). PAC was placed via right internal jugular vein and the correct position was confirmed by PAC waveforms. Continuous cardiac output (CCO), CI and other hemodynamic parameters were monitored at following 5 time points: immediate after anesthesia induction (baseline value), anastomosis of left internal mammary artery to left anterior descending artery (LAD), anastomosis of left circumflex (LCX), anastomosis of posterior descending artery (PDA) and immediate after sternal closure.</p><p><b>RESULTS</b>In the 50 patients, preoperative echocardiography measured left ventricular EF was (52.8 ± 11.5)%, and 35 patients (70%) showed regional wall motion abnormalities. The correlation coefficient of CO monitored by APCO and PAC were 0.70, 0.59, 0.78, 0.74 and 0.85 at each time point. The bias range of CI monitored from both APCO and PAC were (0.39 ± 0.06) L×min(-1)×m(-2), (0.48 ± 0.12) L×min(-1)×m(-2), (0.26 ± 0.06) L×min(-1)×m(-2), (0.27 ± 0.06) L×min(-1)×m(-2), (0.30 ± 0.05) L×min(-1)×m(-2) at each time point. The results of SVR by two hemodynamic monitoring techniques had good correlation during OPCABG. The variation trends of SVR were opposite comparing with the results of CO. SVR collected from PAC obtained the highest value of (1220.0 ± 254.0) dyn×s×cm(-5) at PDA anastomosis, but the highest value obtained from APCO was (1206.0 ± 226.5) dyn×s×cm(-5) in LCX anastomosis.</p><p><b>CONCLUSIONS</b>APCO is feasible in hemodynamic monitoring for patients undergoing OPCABG. The results of hemodynamic monitoring derived from APCO and PAC are closely correlated. Its characterizations of timely, accurate and continuous display of hemodynamic parameters are also obviously demonstrated in the present study.</p>

High volume practice proved the safety of off-pump coronary artery bypass surgery in left main coronary artery lesions: a two-year single center experience / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Left main coronary artery (LMCA) stenosis has been recognized as a risk factor for early death among patients undergoing coronary artery bypass grafting (CABG). This study aimed to assess if LMCA lesions pose an additional risk of early or mid-term mortality and/or a major adverse cardiac and cerebrovascular event (MACCE) after off-pump coronary artery bypass grafting (OPCABG), compared with non-left main coronary artery stenosis (non-mainstem disease).</p><p><b>METHODS</b>From January 1, 2009 to December 31, 2010, 4869 patients had a primary isolated OPCABG procedure at Beijing Anzhen Hospital. According to the pathology of LMCA lesions, they were retrospectively classified as a non-mainstem disease group (n = 3933) or a LMCA group (n = 936). Propensity scores were used to match the two groups, patients from the non-mainstem disease group (n = 831) were also randomly selected to match patients from the LMCA group (n = 831). Freedom from MACCE in the two groups was calculated using the Kaplan-Meier method.</p><p><b>RESULTS</b>The difference in the mortality and the rate of MACCE during the first 30 days between the non-mainstem disease group and the LMCA group did not reach statistical significance (P = 0.429, P = 0.127 respectively). With a mean follow-up of (12.8 ± 7.5) months and a cumulative follow-up of 1769.6 patient-years, the difference in the freedom from MACCEs between the two groups, calculated through Kaplan-Meier method, did not reach statistical significance (P = 0.831).</p><p><b>CONCLUSION</b>Analysis of a high volume of OPCABG procedures proved that LMCA lesions do not pose additional early and mid-term risk to OPCABG. Therefore, a LMCA lesion is as safe as non-mainstem disease lesion during the OPCABG procedure.</p>

Myocardial autophagy variation during acute myocardial infarction in rats: the effects of carvedilol / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The loss of cardiac myocytes is one of the mechanisms involved in acute myocardial infarction (AMI)-related heart failure. Autophagy is a common biological process in eukaryote cells. The relationship between cardiac myocyte loss and autophagy after AMI is still unclear. Carvedilol, a non-selective alpha1- and beta-receptor blocker, also suppresses cardiac myocyte necrosis and apoptosis induced by ischemia. However, the association between the therapeutic effects of carvedilol and autophagy is still not well understood. The aim of the present study was to establish a rat model of AMI and observe changes in autophagy in different zones of the myocardium and the effects of carvedilol on autophagy in AMI rats.</p><p><b>METHODS</b>The animals were randomly assigned to a sham group, an AMI group, a chloroquine intervention group and a carvedilol group. The AMI rat model was established by ligating the left anterior descending coronary artery. The hearts were harvested at 40 minutes, 2 hours, 24 hours and 2 weeks after ligation in the AMI group, at 40 minutes in the chloroquine intervention group and at 2 weeks in other groups. Presence of autophagic vacuoles (AV) in the myocytes was observed by electron microscopy. The expression of autophagy-, anti-apoptotic- and apoptotic-related proteins, MAPLC-3, Beclin-1, Bcl-xl and Bax, were detected by immunohistochemical staining and Western blotting.</p><p><b>RESULTS</b>AVs were not observed in necrotic regions of the myocardium 40 minutes after ligation of the coronary artery. A large number of AVs were found in the region bordering the infarction. Compared with the infarction region and the normal region, the formation of AV was significantly increased in the region bordering the infarction (P < 0.05). The expression of autophagy- and anti-apoptotic-related proteins was significantly increased in the region bordering the infarction. Meanwhile, the expression of apoptotic-related proteins was significantly increased in the infarction region. In the chloroquine intervention group, a large number of initiated AVs (AVis) were found in the necrotic myocardial region. At 2 weeks after AMI, AVs were frequently observed in myocardial cells in the AMI group, the carvedilol group and the sham group, and the number of AVs was significantly increased in the carvedilol group compared with both the AMI group and the sham group (P < 0.05). The expression of autophagy- and anti-apoptotic-related proteins was significantly increased in the carvedilol group compared with that in the AMI group, and the positive expression located in the infarction region and the region bordering the infarction.</p><p><b>CONCLUSIONS</b>AMI induces the formation of AV in the myocardium. The expression of anti-apoptosis-related proteins increases in response to upregulation of autophagy. Carvedilol increases the formation of AVs and upregulates autophagy and anti-apoptosis of the cardiac myocytes after AMI.</p>

Changes of lung microvascular permeability in blunt chest trauma, endotoxemia and their combined injury in rats / 第三军医大学学报

Objective　To observe the changes of the microvascular permeability after blunt chest trauma (BCT), endotoxemia and their combined injury in rats. Methods　After the establishment of the rat models of BCT, endotoxemia and their combined injury in the right lungs, the fluorescein sodium (FINa) content was measured with flurospectrophotometer in lungs 0.5, 1, 4 and 8 h after injury. Results　There was an early obvious increase of the microvascular permeability in the impact lateral (peak at half an hour after injury), and a delayed increase in the contralateral lung (peak at the 8th h) in the BCT group. The FINa content was higher in endotoxemia group than in the BCT group(P<0.05), and lower than that in the combined injury group(P<0.05) in the contralateral lung. Conclusion　Results indicate that there were different pathophysiologic processes among the 3 kinds of injury and the FINa content is a useful index to manifest the changes of microvascular permeability in tissues.

Changes of lung microvascular permeability in blunt chest trauma, endotoxemia and their combined injury in rats / 第三军医大学学报

Objective　To observe the changes of the microvascular permeability after blunt chest trauma (BCT), endotoxemia and their combined injury in rats. Methods　After the establishment of the rat models of BCT, endotoxemia and their combined injury in the right lungs, the fluorescein sodium (FINa) content was measured with flurospectrophotometer in lungs 0.5, 1, 4 and 8 h after injury. Results　There was an early obvious increase of the microvascular permeability in the impact lateral (peak at half an hour after injury), and a delayed increase in the contralateral lung (peak at the 8th h) in the BCT group. The FINa content was higher in endotoxemia group than in the BCT group(P<0.05), and lower than that in the combined injury group(P<0.05) in the contralateral lung. Conclusion　Results indicate that there were different pathophysiologic processes among the 3 kinds of injury and the FINa content is a useful index to manifest the changes of microvascular permeability in tissues.