Objective To investigate the changes and roles of myocardial adenosine triphosphate enzyme(ATPase) in the mechanism of cardiac dysfunction after blunt chest trauma（BCT）. Methods Thirtysix rabbits were divided into 6 groups with random number table, control group, 2 h group, 4 h group, 8 h group, 12 h group and 24 h group, 6 in each group. The models of BCT were established with BIMⅡ biological impact machine, catheterization technique was used through the right jugular artery into the left ventricle measure its pressure. The hemodynamics and the activities of ATPase in myocardial cell plasm, homogenate and mitochondria were measured at preinjury(control group), 2 h, 4 h, 8 h, 12 h and 24 h postinjury. Results Left ventricular endsystolic pressure(LVESP), the maximal ascending rate of left intraventricular pressure(+dp/dtmax), isovolemec pressure(IP) and the maximal physiological velocity(Vpm) decreased significantly at 2 h group after BCT(Plt;0.05）, and recovered to preinjury level in 4 h, 8 h and 12 h group during 4-12 h after BCT; isovolumic relaxation phase left ventricular pressure descending time constant (T). Left ventricular enddiastolic pressure(LVEDP) and the maximal descending rate of left intraventricular pressure(-dp/dtmax) were significantly higher （Plt;0.05, 0.01）. The activity of ATPase in homogenate, mitochondria and cell plasm decreased significantly at 2 h group and 4 h group after BCT（Plt;0.05, 001, respectively）, and 8 h group and 12 h group recovered after BCT. There was negative correlations between [CM(159mm]LVEDP and -dp/dtmax and the decrease of the activity of Na+-K+-ATPase in homogenate（r=-0.674, -0.691, Plt;0.05）, the Ca2+-ATPase in homogenate（r=-0.613,-0.642, Plt;0.05）, the Na+-K+-ATPase in mitochondria（r=-0.622,-0.616, Plt;0.05）,the Ca2+-ATPase in myocardial cell plasm（r=-0.672,-0.658, Plt;0.05）, the Na+-K+-ATPase in myocardial cell plasm（r=-0.627,-0.632,Plt;0.05）,and the Mg2+-ATPase in myocardial cell plasm（r=-0.677,-0.661, Plt;0.05）. Conclusion The left ventricular function is impaired obviously after BCT, especially in diastolic phase. The decrease of the activity of ATPase in myocardial cells may be one of the reasons of cardiac dysfunction after BCT.
Objective To investigate the changed rules of the cardiac functions in rabbits and to provide theoretical gists for clinical diagnosis and treatment after blunt chest trauma(BCT). Methods Using the models of moderate to severe BCT with BIM-Ⅱ Bio-impactor in 20 rabbits to examinate the cardiac functions with cardiac catheterization, the single photonemission computed tomography(SPECT) and the Doppler echocardiography at preinjury and 1h, 2h, 4h, 6h, 8h, 12h and 24h after BCT. Results Central venous pressure( CVP）, left ventricular enddiastolic pressure (LVEDP) and the decreasing time constant of left intraventricular pressure (T) at 24h after trauma were higher obviously than those before trauma (Plt;0.05,0.01). The -dp/dtmax at 24h after trauma was lower markedly than that before trauma (Plt;0.05 ). The ejection fraction(EF),1/3 EF, 1/3 ejection rate（1/3ER） and the ratio of 1/3 filling rate (1/3FR) to 1/3ER of the right ventricle at 24h after impacted were lower markedly than those before impacted (Plt;0.05). The peak filling rate, 1/3 filling fraction, 1/3 filling rate, the ratio of peak filling rate to peak ejection rate and the ratio of 1/3FR to 1/3ER of the left ventricular at 24h after impacted were lower obviously than those before impacted (Plt;0.05, 0.01). Conclusion The cardiac functions are changed significantly after BCT. The expressions of the right ventricular dysfunctions mainly are systolic dysfunction while the left ventricular dysfunctions are mainly diastolic dysfunction after BCT. All the cardiac catheterization, SPECT and the Doppler echocardiography are beneficial to the diagnosis of cardiac dysfunction after BCT. The SPECT is more exactitude and the Doppler echocardiography is more cheaper.
Abstract: Objective To investigate the effect of autologous bone marrow mesenchymal stem cells (MSCs) transplantation on cardiac function and their proliferation and differentiation in the post-infarct myocardium in rabbits. Methods Twenty New Zealand rabbits were randomly divided into two groups, the autologous bone marrow mesenchymal stem cells group (MSCs group,n=10) and control group (n=10). Myocardial infarct model was set up by ligation of the left anterior descending (LAD), two weeks after establishment of the infarct model,either 400μl of cell suspension (total cells 1×106) labled by 1,1’-dioctadecyl3,3,3’,3’-tetramethyl indocarbocyanine perchlorate (Dil) or a comparable volume of L-DMEM medium were autologously transplanted into several different points of the periphery of the scar respectively. To evaluate the heart function, echocardiography were performed before modeling,two weeks after modeling, 2 and 4 weeks after the cells transplantation for asurements of left ventricular end systolic diameter (LVESD) and left ventricular end diastolic diameter (LVEDD), tocalculate left ventricular eject fraction(LVEF) and left ventricular fractional shortening (LVFS). Meanwhile the myocardial contrast echocardiography (MCE) were performed for evaluating the blood perfusion of the post-infarct myocardium. Eight weeks after the transplantation, the animalswere undergoing euthanasia, specimens were acquired for pathology. Results Echocardiography indicated that:The LVEF and LVFS between two groups were fundamentally the same before modeling,two weeks after modeling respectively (0.72±0.08 vs. 0.71±0.04,0.56±0.11 vs. 0.55±0.09; 0.35±0.06 vs. 0.35±0.04, 0.24±0.08 vs. 0.23±0.03, Pgt;0.05), but those were improved significantly in group MSCs when compared with control group at two weeks and four weeks after the cells transplantation(0.71±0.05 vs. 0.60±0.05，0.72±0.07 vs. 0.62±0.08 and 0.34±0.03 vs. 0.29±0.01， 0.35±0.06 vs. 0.27±0.05 respectively,Plt;0.05). There were no differences in LVESD and LVEDD between two groups in any time points(Pgt;0.05). MCE showed the blood perfusion of the infarct myocardium were improved two and four weeks after the cell transplantation. Pathology indicated that Dil positive cells were survived in MSCs transplanted hearts, stained positively for αsarcomeric actin and desmin eight weeks after cell transplantation, HE slides indicated that the capillary density in all the cells transplanted hearts were much higher when compared with control group (38.6±7.6/mm2 vs. 21.4±3.9/mm2，Plt;0.05). ConclusionMSCs can differentiate into cardiomyocytes, improve myocardial perfusion and cardiac function when transplanted into ischemic myocardium.
Objective To investigate the perioperative changes of serum brain natriuretic peptide (BNP) concentrations in patients undergoing cardiac valve replacement. Methods There were 20 patients admitted to the study, the serum BNP concentrations were measured before cardiac surgery, 24 hours, 7days, 14 days, and 30 days after operation. The preoperative NYHA cardiac function and the left ventricular ejection fraction(LVEF) were measured by echocardiogram. Results The preoperative BNP level was the baseline, it elevated markedly and acutely to a peak value 24 hours after operation ( P =0.003), then the BNP decreased 7 days later, but was still higher than the concentration before operation ( P =0.015), 14 days later it reached to the concentration before operation, 30 days later it was mild lower than preoperative BNP level, but there was no significant difference. There was a positive correlation between NYHA and BNP ( r =0.69, P lt;0.05), but no correlation between LVEF and BNP( r =0.29, P gt;0 05). Conclusion The preoperative serum BNP concentration can reflect the preoperative cardiac function in patients undergoing cardiac valve replacement, the high BNP level indicates the poor cardiac function. The BNP sharply elevated in the early time after operation, then gradually decreased in the late phase postoperation.
Objective To study the influence of autologous bone mesenchymal stem cells (BMSCs) on myocardial structure and cardiac function after being implantated into acute infarcted myocardial site. Methods Bone marrow was aspirated from the posterosuperior iliac spine of Guizhou Xiang swine. After being isolated, cultured and co cultured with 5 azacytidine, either autologous BMSCs (total cells 2×10 6, experimental group, n =12), or a comparable volume of culture medium (control group, n =12), was injected into the left anterior descending(LAD) branch of coronary artery just distal to the ligation site of the LAD. The same volume of BMSCs or culture medium was injected into several spots in the infarcted myocardium. Echocardiographic measurements were performed three or six weeks after implantation to assess the myocardial structure and cardiac function. Results Left ventricular function, including eject fraction(EF), fractional shortening and wall thickening, were higher in experimental group when compared with control group. The thickness of the ventricular wall and septum was also found increased while the left ventricular chamber size was smaller in experimental group. Conclusion Implantation of BMSCs into the infarcted myocardium is believed to attenuate the remodeling process, inhibit the extent of wall thinning and dilatation of the ventricular chamber. BMSCs implantation may also improve the contractile ability of the myocardium and cardiac function.
Objective To observe the effect of BMSCs on the cardiac function in diabetes mellitus (DM) rats through injecting BMSCs into the ventricular wall of the diabetic rats and investigate its mechanism. Methods BMSCs isolated from male SD rats (3-4 months old) were cultured in vitro, and the cells at passage 5 underwent DAPI label ing. Thirty clean grade SD inbred strain male rats weighing about 250 g were randomized into the normal control group (group A), the DM group (group B), and the cell transplantation group (group C). The rats in groups B and C received high fat forage for 4 weeks and the intraperitoneal injection of 30 mg/kg streptozotocin to made the experimental model of type II DM. PBS and DAPI-labeledpassage 5 BMSCs (1 × 105/μL, 160 μL) were injected into the ventricular wall of the rats in groups B and C, respectively. After feeding those rats with high fat forage for another 8 weeks, the apoptosis of myocardial cells was detected by TUNEL, the cardiac function was evaluated with multi-channel physiology recorder, the myocardium APPL1 protein expression was detected by Western blot and immunohistochemistry test, and the NO content was detected by nitrate reductase method. Group C underwent all those tests 16 weeks after taking basic forage. Results In group A, the apoptosis rate was 6.14% ± 0.02%, the AAPL1 level was 2.79 ± 0.32, left ventricular -dP/dt (LV-dP/dt) was (613.27 ± 125.36) mm Hg/s (1 mm Hg=0.133 kPa), the left ventricular end-diastol ic pressure (LVEDP) was (10.06 ± 3.24) mm Hg, and the NO content was (91.54 ± 6.15) nmol/mL. In group B, the apoptosis rate was 45.71% ± 0.04%, the AAPL1 level 1.08 ± 0.24 decreased significantly when compared with group A, the LVdP/ dt was (437.58 ± 117.58) mm Hg/s, the LVEDP was (17.89 ± 2.35) mm Hg, and the NO content was (38.91±8.67) nmol/mL. In group C, the apoptosis rate was 27.43% ± 0.03%, the APPL1 expression level was 2.03 ± 0.22, the LV -dP/dt was (559.38 ± 97.37) mm Hg/ s, the LVEDP was (12.55 ± 2.87) mm Hg, and the NO content was (138.79 ± 7.23) nmol/ mL. For the above mentioned parameters, there was significant difference between group A and group B (P lt; 0.05), and between group B and group C (P lt; 0.05). Conclusion BMSCs transplantation can improve the cardiac function of diabetic rats. Its possible mechanismmay be related to the activation of APPL1 signaling pathway and the increase of NO content.
Objective To investigate effects of the autologous bone mesenchymal stem cells (MSCs) enriched by the small intestinal submucosa (SIS) film implantation on the myocardial structure, cardiac function, and compensator y circulation after myocardial infarction in the goats. Methods Sixteen black goats were selected and divided randomly into the control group (n=8)and the experimental group (n=8). The chronic myocardial infarction models were made by the ligation of the far end of the left anterior desc ending coronary artery. At the same time, MSCs were aspired from the thigh bone of the goats in the experimental group. MSCs were isolated by the centrifu gation through a percoll step gradient and purified by the plating culture and depletion of the non-adherent cells. Primary MSCs were cultured in the DMEM me dium supplemented with the fetal bovine serum in vitro. After that, the cultures were labeled by 5- BrdU. The active cells were transplanted into the SIS film. Six weeks after the ligation, the MSCs-SIS film was implanted by its being sutured onto the infarction area; whereas, the control group underwent a shamoperation. In both groups, echocardiographic measurements were performed before infarction, 6 weeks after infarction and 6 weeks after the MSC-collagen mplantion, respectively, to assess the myocardial structure and ca rdiac function. The left coronary artery angiography was performed with the digi tal subtraction angiography. Results In an assessment of the left ventricular function, at 6 weeks after operation, t he stroke volume and the ejection fraction of the control group and the experim ental group were 42.81±4.91, 37.06±4.75 ml and 59.20%±5.41%, 44.56%±4.23%, respectively (Plt;0.05). The enddisatolic volume and the endsystolic volume of the control group and the experimental group were 72.55±8.13, 83.31±8.61 ml and 29.75±5.98, 46.25±6.68 ml, respectively (Plt;0.05). The maximal velocity of peak E of contral group and experimental group were 54.8 5±6.35 cm/s and 43.14±4.81cm/s (Plt;0.01); and the maximal velocity of peak A o f control group and experimental grouop were 52.33±6.65 cm/s and 56.91±6.34 cm/s (Pgt;0.05). Echocowdiogr aphy sho wing a distinctly dilatation of left ventricle with the ventricular dyskinesia i n contral group, but without the ventricular dyskinesia in experimental group. T he selective-coronary evngiography revealed that the obvious compensatory circu l ation established between the anterior descending branch and the left circumflex branch in the experimental group. Conclusion Implantation of the autologus MSCs enriched by the SIS film can prevent dilatation of the left ventricular chamber and can improve the contractile ability of the myocardium, cardiac function, and collateral perfusion.
Objective To evaluate the efficacy of recombinant human brain natriuretic peptide (rhBNP) on Chinese patients with congestive heart failure by meta analysis. Methods Both foreign language databases including PubMed, EMbase, The Cochrane Library (Issue 3, 2009) and Chinese databases involving CBM, VIP and CJFD were searched to identify randomized controlled trials (RCTs) that reported the effect of rhBNP on the heart function (left ventricular ejection fraction (LVEF) and the recent level of improvement in cardiac function) and its side effects of Chinese patients with congestive heart failure. Two reviewers assessed the quality of each trial and extracted data independently. The Cochrane Collaboration’s RevMan 4.2.8 software was used for statistical analysis. Results Nineteen RCTs were included, all of which came from internal. The methodological quality of the included studies was good. The baseline data of each trial were comparable. The results of meta-analyses showed: (1) the improvement of LVEF was higher in the rhBNP group than that in the blank control group (WMD=7.22, 95%CI 3.15 to 11.291, P=0.000 5). The level of improvement in cardiac function was better in the rhBNP group than those in the blank control group (OR=5.48, 95%CI 1.61 to 18.65, P=0.007), the nitroglycerin group (OR=3.60, 95%CI 2.02 to 6.41, Plt;0.000 1), and the sodium nitroprusside group (OR=3.21, 95%CI 0.12 to 85.20, P=0.49). The incidence of side effects was lower in the rhBNP group than that in the nitroglycerin group (OR=0.23, 95%CI 0.11 to 0.47, Plt;0.000 1), and the sodium nitroprusside group (OR=0.30, 95%CI 0.11 to 0.82, P=0.02). Moreover, the results of sensitivity analysis were also consistent with the above findings. Conclusion Recombinant human brain natriuretic peptide can effectively improve the hemodynamics and cardiac function level of Chinese population of patients with heart failure. The treatment doses are safe and tolerant, so it is recommended to clinical use.
ObjectiveTo investigate the clinical significance of cardiac function index (CFI) and global ejection fraction (GEF), derived from single-indicator transpulmonary thermodilution technique, in assessment of cardiac function in critically ill patients. MethodsA prospective clinical observational study was conducted in the Intensive Care Unit of the First Affiliated Hospital of Guangzhou Medical University. Between January 2012 and December 2012, 39 patients who underwent PiCCO monitoring were recruited, including 18 cases with left ventricular systolic dysfunction and 21 cases without left ventricular systolic dysfunction. Both groups underwent transpulmonary thermodilution measurements and transthoracic cardiac ultrasonography. Pearson correlation analysis was conduced to assess the correlation between left ventricular ejection fraction (LVEF) and CFI and GEF. ROC curve was established to calculate the predicted threshold of CFI and GEF for diagnosing cardiac insufficiency. ResultsLVEF was significantly correlated with CFI and GEF (r=0.553, P < 0.005; r=0.468, P < 0.005). The area under ROC curve of CFI, GEF and LVEF for diagnosing cardiac insufficiency was 0.885, 0.862 and 0.903, respectively (P > 0.05 for comparison). The cut-off value of CFI for predicting cardiac insufficiency was 4.25/min, with a sensitivity of 77.8% and a specificity of 88.9%. The cut-off value of GEF for predicting cardiac dysfunction was 19.5/min, with a sensitivity of 88.9% and a specificity of 66.7%. ConclusionCFI and GEF measured by transpulmonary thermodilution correlate well with LVEF assessed by transthoracic echocardiography, both can be used for assessment of left ventricular systolic function.
ObjectiveTo evaluate the mid-term recovery of cardiac function after heart valve replacement and concomitant bipolar radiofrequency ablation for atrial fibrillation (AF). Methods Clinical data of 191 patients with heart valve disease and AF in the same surgical team of Xinqiao Hospital from January 2011 Jan to December 2013 was retrospectively analyzed. Heart valve replacement was performed for a control group (n=93), which includes 31 males and 62 females with their age of 48.33±7.55 years and AF duration of 4.80±2.03 years. Valve replacement and concomitant bipolar radiofrequency ablation was performed for a synchronism ablation group (n=98), which includes 27 males and 71 females with their age of 46.95±7.70 years and AF duration of 5.06±2.26 years. The echocardiogram, electrocardiogram and complications at hospitalization, 6 months, 1 year and 2 year after operation were analyzed. ResultsNo in-hospital death occurred. There were statistical differences in aortic cross-clamp time, cardiopulmonary bypass time, tricuspid ring, ICU stay, total volume of postoperative drainage between the two groups. All the patients were followed up for 2 years. Two years postoperatively, in the synchronism ablation group, 85 patients (86.73%) were followed up, 1 patient with cerebral embolism, 2 patients with cerebral hemorrhage. In the control group, 85 patients (91.40%) were followed up, 4 patients with cerebral embolism, 2 patients with cerebral hemorrhage. There were no death, cardiac rupture, and permanent cardiac pacemaker implantation in the two groups during the follow-up. One year and 2 years postoperative fractional shortening of the synchronism ablation group was significantly higher than those of the control group (37.18%±5.35% vs. 34.72%±6.40%, P=0.007; 37.95%±7.99% vs. 35.18%±5.15%, P=0.008). One year and 2 years postoperative left ventricular ejection fraction of the synchronism ablation group was significantly higher than that of the control group (66.27%±6.99% vs. 63.33%±8.14%, P=0.012). The rate of self-feeling cardiac function improvement in 1 year and 2 years after surgery of the synchronism ablation group was significantly higher than that of the control group (85.39% vs. 72.94%, P=0.005; 84.71% vs. 68.24%, P=0.005). ConclusionCardiac function of the mid-term after the valve replacement and concomitant bipolar radiofrequency ablation for atrial fibrillation obviously improves.