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Advanced heart failure(AHF)is a global epidemic with high morbidity and mortality.Heart transplantation has been the main method for the treatment of AHF.However, for the extreme shortage of organ donations, heart transplanta-tion is no obvious increase.Left ventricular assist devices(LVADs)have become a viable therapeutic approach as a bridge to heart transplantation, as well as destination therapy or part of the bridge to recovery.This review focuses on the therapeutic effect with VAD, current controversies and prospects.
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Objective To observe the pathophysiological change of right heart remodeling model of beagle dogs caused by tricuspid regurgitation. Methods Six beagle dogs were separated to TR group and sham operation group randomly and equally. The anterior and posterior leaflets of tricuspid valve of beagle dogs from TR group were cut off under direct vision on the beating heart. The echocardiography data were measured pre-operation and post-operation 3, 6, 12 months respectively and autopsy results were acquired after the sacrifice of two animals who had been raised for 18 months. Results The operation was successful and survival 100%. The weight of TR group increased, and the echocardiography showed right atrium and ventricle enlargement and right heart dysfunction. The autopsy of TR group found myocardial fibrosis , liver cirrhosis and ascites. All of the results indicated the occurrence of right heart remodeling and right heart failure. There is no significant difference in sham operation group before or after operation. Conclusion The myocardial fibrosis is one of the pathological basis of right heart remodeling.
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BACKGROUND:Calcium metaphosphate has excel ent biocompatibility, degradability, and cel affinity. Human bone marrow mesenchymal stem cel s can grow and proliferate in the pores of the porous calcium metaphosphate, but less is known about calcium metaphosphate nanoparticles. OBJECTIVE:To prepare calcium metaphosphate nanoparticles, and to analyze the effect of calcium metaphosphate nanoparticles at different concentrations on apoptosis of human bone marrow mesenchymal stem cel s by flow cytometry. METHODS:The calcium metaphosphate nanoparticles were prepared by wet bal mil ing. Scanning electron microscopy and transmission electron microscopy were used to observe the morphology of the calcium metaphosphate nanoparticles, and the crystal structure of nanoparticles was analyzed by X-ray diffraction. Calcium metaphosphate nanoparticles were mixed in the CYAGON Oricel TM basal medium, and the concentrations of calcium metaphosphate nanoparticles in the medium were 10, 1, 0.1 mg/L. Human bone marrow mesenchymal stem cel s were cultured for 7 days in the above-mentioned media, and apoptosis of human bone marrow mesenchymal stem cel s was analyzed by flow cytometry. RESULTS AND CONCLUSION:Calcium metaphosphate nanoparticles were successful y prepared by wet bal mil ing, irregular in shape, and the mean diameter was 10-30 nm. X-ray diffraction results showed the crystal structure of nonaparticles was mainlyβ-Ca(PO3)2. The cel ratio of G0/G1 phase and G2/M phase in 10 mg/L group was obviously higher than that in 1, 0.1 mg/L groups (P<0.01). The cel apoptosis rates during the early, middle, late stages in 10 mg/L group were obviously higher than those in 1, 0.1 mg/L groups (P<0.01), and the total cel apoptosis was also significantly increased in 10 mg/L group (P<0.01). These findings indicate that human bone marrow mesenchymal stem cel s proliferation can be inhibited by calcium metaphosphate nanoparticles, and apoptosis rate is increased significantly when the concentration of calcium metaphosphate nanoparticles increases from 1 mg/L to 10 mg/L.
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BACKGROUND:The mechanical valves used in the adult Luo-Ye pump have a large size and great destruction to blood, which are not suitable for infant ventricular assist pump. Therefore, designing and producing a high molecular valve with smal size and low incidence of thrombosis is a research hotspot. OBJECTIVE:To design and produce a valve of 20 mL infant Luo-Ye pump, and to test its basic functions and fatigue properties. METHODS:The size and shape of valve was designed with MASTERCAM software, polyurethane valve was obtained through producing the valve model and plastic injection;the static leakage, pressure drop and fatigue resistance of polyurethane valve were tested according to the ISO5840 requirements. RESULTS AND CONCLUSION:The polyurethane trefoil valve was produced, but the failure rate of plastic injection was high;the basic function of the trefoil valve met the ISO5840 requirements bascial y;after continuously operated 1.0×107 times, stroke volume of 20 mL Luo-Ye pump was changed 5.2%, and two polyurethane valves and valve leaflets did not change and damage. Polyurethane trefoil valve was designed and produced successful y;polyurethane valves could meet the needs of 20 mL Luo-Ye pump, which already have the ability to clinical trials.
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<p><b>OBJECTIVE</b>To summarize the experience with surgical correction of tetralogy of Fallot in adults over 40 years of age.</p><p><b>METHODS</b>From November 1985 to July 2008, 9 male and 11 female patients aged 41-53 years (mean 46.3±3.5 years) underwent total surgical correction for tetralogy of Fallot. Twelve patients had preoperative NYHA class III cardiac function. The common comorbidities included infective endocarditis, cerebral abscess, cerebral infarction, renal dysfunction, and tricuspid insufficiency. Surgical corrections were carried out at the anatomical or physiological level.</p><p><b>RESULTS</b>Nineteen patients received right ventriculotomy to relieve right ventricular outflow obstruction and for ventricular septal defect closure, and 1 patient had Fontan operation. Two patients died after the surgery for heart failure and ventricular fibrillation. The average cardiopulmonary bypass time, aortic clamp time, and postoperative ventilation time was 142.9±36.3 min, 89.9±25.1 min, and 72.0±17.5 h, respectively. Postoperative low cardiac output syndrome occurred in 5 cases, septic shock in 1 case, secondary renal failure in 1 case, and bleeding in 2 cases. Echocardiography showed a significant postoperative reduction of the mean right ventricular outflow tract velocity from 4.29±1.36 m/s to 2.13±0.83 m/s (P<0.01); the right ventricular longitudinal dimension exhibited no significant changes postoperatively (57.1±6.7 mm vs 55.1±7.0 mm, P=0.65).</p><p><b>CONCLUSIONS</b>Surgical correction of the tetralogy of Fallot in patients over 40 years is highly risky and requires appropriate management of cardiac failure, careful myocardial protection, and thorough intracardiac lesion correction to decrease surgical complications.</p>
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Adult , Female , Humans , Male , Middle Aged , Tetralogy of Fallot , General Surgery , Treatment OutcomeABSTRACT
Objective To evaluate the risk factors for the postoperative acute renal failure requiring dialysis (ARF-D)after heart valve surgery. Methods Adult patients (age≤18 years) underwent valve surgery with preoperative serum creatinine ＜300 μmol/L were included between January 2005 and December 2008. Fifty patients developed ARF-D within 30 days postoperatively (ARF-D group). While random 220 patients had the same operation without ARF-D served as the control group. Univariate analysis and multivariable logistic regression were used to identify risk factors of ARF-D after valve surgery.Results The incidence of ARF-D was 1.78%, and the early mortality rate was 65.5%. Multivariate analysis identified the following independent risk factors of ARF-D: age, previous cardiac surgery, preoperative serum creatinine, NYHA class Ⅳ,and low cardiac output syndrome. ARF-D group had a longer hospital stay and ICU stay than that of the control group ( P ＜0.001 ). Conclusion Conclusion ARF-D had a higher mortality rate and longer hospital stay following heart valve surgery.Age, previous cardiac surgery, preoperative serum creatinine, NYHA class Ⅳ, and low cardiac output syndrome were the independent risk factors of ARF-D after heart valve surgery.
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Objective To validate of the Chinese system for cardiac operative risk evaluation (SinoSCORE) in Cantonese surgery patients. Methods Data from Guangdong Cardiovascular Institute in the period January 2004 through December 2008 were analyzed on 2462 Cantonese heart surgery patients. First, compared risk factors of this series and database of SinoSCORE, and then calculated the additive score of each patients and evaluate the discrimination and calibration of sinoSCORE in Cantonese patients. Results There were some differences between the risk factors of patients from two groups. The gender,smoking, diabetes, hyperlipemia, hypertension, chronic pulmonary diseases, stroke, cardiovascular surgery history, left main disease, atrial fibrillation/atrial flutter, pulmonary arterial hypertension, concomitant coronary surgery and concomitant valve surgery in Cantonese patients were different between two groups. However, The SinoSCORE was able to predict the in-hospital mortality of senior patients with good discrimination ( Hosmer-Lemeshow test, P = 0. 34 ) and calibration ( the area under the receiver operating characteristic curve, 0.84, P ＜ 0.01 ). Conclusion SinoSCORE was able to predict the in-hospital mortality of Cantonese heart surgery patients.
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Objective To analyze causes for postoperative coxa vara and anti-rotation nail cutting-out after treatment of brittle femoral intertrochanteric fractures with proximal femoral nails ( PFN ).Methods An retrospective study was done on 227 patients with intertrochanteric fracture treated with PFN from June 2006 to February 2009. The causes for postoperative coxa vara and anti-rotation nail cutting-out were analyzed. Harris score was used to evaluate the functional recovery of the hip joint. Results Of all, 221 patients were followed up for 12-48 months (mean 23 months) and six patients were died from serious internal disease within one year. According to Harris evaluation system, the results were excellent and good in 183 patients, fair in 30 and poor in 14. Postoperative coxa vara and anti-rotation nail cuttingout occurred in 16 patients, eight of whom received reoperation to remove internal fixation and skeletal traction at abducent position and the other eight received prosthetic replacement. Conclusions Treatment of proximal femoral fracture with PFN requires a high precision of reduction and operation. Many factors including lateral cortical bone conditions of tuberosity, postoperative patient's cognitive condition,use of improved Jensen-Evans classification and Singh's classification may affect operation outcome.
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Objective To investigate the surgical technique and outcomes of replacement of chordae tendineae in mitral valve repair, and evaluate the value of real-time three-dimensional transesophageal echocardiography in the perioperative period. Methods Thirty-one patients with mitral valve prolapse underwent mitral valve repair using chordae tendineae replacement concomitant with implantation of valveplasty ring. A 4-0 Goretex sutures was used for reconstruction of artificial chordae. Realtime three-dimensional transesophageal echocardiography was performed in all the patients during the preoperative, intraoperatire, and postoperative periods. The length of the chordae tendineae under the A1 section of the anterior leaflet and the P1 section of the posterior leaflet were measured and considered the normal length of chordae tendineae by real-time three-dimensional transesophageal echocardiography preoperatively. These pre-determined normal chordal lengths helped intraoperatively to approximate the length of the artificial chordae used and postoperatively to gauge the success of the procedures. The same values were used again postoperatively to gauge the success of intervention. Full flexible valveplasty rings were used in all the patients.Results There was no operative death. The mean cardiopulmonary bypass (CPB) and aortic cross clamp time were ( 142. 0 ±31.2 ) min and (98.0 ± 22.5 ) min, respectively. One patient' s intraoperative echocardiography upon termination of CPB showed persistent severe mitral regurgitation and was converted to mitral valve replacement. This patient was not included in the study group. The mean number of artificial chordae per patient was (2.0 ± 1.5 ) , range from 1 to 3. The mean preoperatively measured normal chordal length was ( 21.0 ± 2.5 ) mm, and the mean postoperative artificial chordal length was ( 20.0 ± 2.2 )mm. The difference was not significant. The follow-up interval was from 3 to 30 months and the follow-up rate was 98%. During the follow-up period, there was no late death. Trace mitral regurgitation (MR) was detected in 15 patients, mild and moderate MR were detected in 1 for each. No severe MR was detected. The freedom from reoperation was 100% during follow-up.There were no documented artificial chordae ruptures. Conclusion Conclusion Artificial chordal replacement with Gore-tex suture in mitral valve repair in this group of patients with mitral valve prolapse appears to have satisfactory early and mid-term results. Real-time three-dimensional transesophageal echocardiography plays a critical role in this technique. Real-time threedimensional transesophageal echocardiography can exactly predict the length of artificial chordae, which is helpful to improve the outcomes of mitral valve repair. However, longer term follow-up and larger series are required to validate our findings.
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Objective: To evaluate the mitral, aortic and tricuspid valve replacement for rheumatic heart disease. Methods: From June 1990 to June 2001, 941 patients underwent valve replacement. Among them, 24 patients underwent simultaneously mitral, aortic and tricuspid valve replacement. There were 17 females and 7 males, with mean age of 36 years (ranged from 18 to 59 years). Eight patients had previous closed mitral valvotomy. Eleven patients complicated with left atrium thrombus, 16 with hapotomeglia, and 8 with ascites. The X ray results showed that the C/T ratio was 0.66 to 0.91. The heart function (NYHA) was class III in 9, and class IV in 15. All patients had combined mitral, aortic valve lesions associated with severe tricuspid valve regurgitation. Results: One patient died postoperatively with an operative mortality of 4.2%. 23 patients followed up from 20 to 36 months (mean, 26.4 months). There was no thrombolism and anticoagulant related hemorrhage. The echocardiography demonstrated the diameter of left atrium right ventricle, and LVDd significantly decreased after operation. The heart function was also significantly improved. Conclusion: The combination of mitral, aortic and tricuspid valve replacement could achieve a satisfactory result with low mortality and better recovery of heart function.
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Objective: This study was undertaken to explore the effect of left ventricular assist device (LVAD) on failing heart after myocardial ischemia. By detecting the changes of plasma atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and cardiac troponin I (cTnI) levels within 6 hours after the implantation of LVAD, we review the basis on which neurohormones may be used to determine prognoses of failing heart and choose an optimal predictor. Methods: 15 adult healthy dogs were divided into 3 groups randomly. The LVAD was implanted in LA-AO bypass in all three groups. Myocardial ischemia was induced by ligating the main left anterior descending coronary artery (LAD). In group A, after a ligation of 10 minutes, the myocardium was reperfused for 6 hours. In group B, after a ligation of 40 minutes, the myocardium was reperfused for 6 hours. In group C, after a ligation of 40 minutes, the LVAD was used for LV support for 6 hours. Results: After 6 hours reperfusion,in group C, the hemodynamics was significantly improved, the ANP, BNP and cTnI were return to normal level, and myocardial ultrastructure was recovered significantly. While in group B, the hemodynamic, the neurohormones, and myocardial ultrastructure were worse. Relational analysis demonstrated that ANP and cTnI levels were influenced by hemodynamics obviously, but there was a weak relationship between circulating BNP and hemodynamics. Plasma BNP level was able to identify the cardiac function status. Conclusion: LVAD can be beneficial to improve cardiac function and can reduce the plasma levels of ANP, BNP and cTnI. Plasma BNP level can identify the cardiac function status. Those findings indicated that plasma BNP determination provides important prognostic information about cardiac function and may be a better prognostic indicator.
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Objective To evaluate the effects of leucocyte-depleting filtration on systemic inflammatory response in patients undergoing valve surgery. Methods Fifty-two patients underwent elective mitral valve or mitral and aortic valves replacement surgery in this study. Patients were randomly divided into two groups. Each group (n=26) was placed on the same cardiopulmonary bypass (CPB) circuit except for the arterial line filter. One group of patients (CG) used the TERUMO ordinary arterial line filter as a control, and the Pall LG-6 leucocyte-depleting arterial line filter and TERUMO ordinary arterial line filter were incorporated into the arterial line of extracorporeal circuit in a parallel way in the EG. The leukocyte-depleting filters were used from 5-10 minutes before aortic cross clamp release to the end of CPB. Intra- and postoperative variables consist of leucocyte counts, serum levels of cytokines and complement C_3, body temperature and the usage of antibiotics. Statistical analysis with indepent-samples t-tests, paired-samples t-test, correlate and chi-square (SPSS11.5) was performed on all data to test for significant differences. A P value of
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To compare the effects on hemodynamics of univentricular support with that of biventricular support on experimental ischemic biventricular dysfunction so as to provide experimental basis for clinical usage of the Luo-Ye pump. Eight canines were placed with a left ventricular assist device (LVAD; left atrial-aorta bypass) and a right ventricular assist device (RVAD; right atrial-pulmonary artery bypass). Left anterior descending coronary artery(LAD) was ligated, three minutes later, the proximal of right coronary artery (RCA) was ligated to establish animal madel of acute ischemic biventricular dysfunction. First start the LVAD, and then RVAD was started five minutes later. The hemodynamic data were recorded including central venous pressure(CVP), cardiac output (CO), mean artery pressure(MAP), and pulmonary artery pressure(PAP) and pulmonary capillary wedge pressure (PCWP). During biventricular assist devices (BVAD) the hemodynamics were improved remarkably, MAP increased from 37.4 +/- 8.8 mmHg to 84.2 +/- 9.7 mmHg (P < 0.01) (the normal level), CO increased from 0.82 +/- 0.1 L/min to 1.33 +/- 0.12 L/min (P < 0.01), CVP decreased from 14.6 +/- 2.3 cmH2O to 4.2 +/- 1.5 cmH2O (P < 0.01), PCWP decreased significantly from 14 +/- 3.9 mmHg to 1.6 +/- 0.9 mmHg. These data suggest that LVAD during biventricular dysfunction could not improve the hemodynamics to normal level. Howere BVAD could increase CO and MAP to normal level and decrease heart work and myocardial oxygen consumption, which could help to improve myocardial metabolism and myocardial function. Therefore, BVAD is the first choice in treating severe biventricular dysfunction which was not respond to drug therapy and intra-aortic balloon pump (IABP).
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Animals , Dogs , Heart-Assist Devices , Hemodynamics , Myocardial Ischemia , Ventricular Dysfunction , General SurgeryABSTRACT
Electrocardiac signal is one of the most important signals which is used to trigger ventricular assist device (VAD), and the delay time of VAD assistance is very important to get a satisfied result. Proper delay will give VAD relatively enough time to assist, avoiding left heart failure caused by the collision of the heart and VAD during systolic phase. This becomes much more important when the left atrium drainage is insufficient. The aim of our study is to set up an equation to calculate the delay time by RR interval. We try to set up an equation about RR and R-Ao like: R-Ao = A x (RR)n + B(A and B are constant). RR represents the RR interval and R-Ao represents the duration of the period between the peak point of QRS and the point of aortic valve closing; First, calculate RR according to weighting average method, and then, calculate the anticipant R-Ao according to the before-mentioned equation. After adjustment, R-Ao will be used as assistance delay time. R-R interval was measured in 457 selected pediatric patients who were undergiong left heart catheterization and who did not have arrhythmias. From the ECG recording during catheterization, R-R interval was measured while R-Ao was obtained from aortic pressure wave chart; Plot graphs with R-Ao as dependent variable and (RR)n as independent variable; find out correlating model and calculate the arguments A and B of R-Ao = A x (RR)n + B. The results showed that the relation between (RR)1/3 and R-Ao is the most significant, the relation coefficient is 0.733, the regress coefficient is -0.182 (P < 0.001) and the interception is 1.070. This means that R-Ao = (-0.182) (RR) 1/3 + 1.070. The likelyhood degrees of different sections differ markedly. When heart rate is less than 120 beats per min. The relation argument is about 0.733 while 0.45 when heart rate is more than 120 beats per min, Therefore, we can use the equation R-Ao = (-0.182) (RR)1/3 + 1.070 to calculate R-Ao when heart rate is less than 120 beats per min.
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Adolescent , Child , Child, Preschool , Humans , Algorithms , Counterpulsation , Methods , Electrocardiography , Heart , Physiology , Heart-Assist Devices , Signal Processing, Computer-AssistedABSTRACT
Objective To summarize the experience of radical treatment of tetralogy of fallot in adults.Method Between Nov. 1985 and May 2005,115 patients over 18 years of age with tetralogy of fallot underwent total surgical correction.Longitudinal or oblique right ventriculotomy was used to ensure complete release right ventricular outflow obstruction and complete ventricular septal defect closure.Transannular patches were used in 74 patients,right ventricular outflow tract(RVOT) patches in 37 cases,primary closure of right ventricle in 5 cases,respectively.One patient had separate pulmonary main artery and RVOT enlargement.Results Seven patients had residual septal defect and 3 cases suffered from residual RVOT obstruction.Severe cardiac output syndrome occurred in 10 patients and 6 patients died early postoperatively with the mortality rate of 5.22%.Conclusion By careful surgical management,the treatment of total correction in adult patients may result in good effectiveness.
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Objective: To investigate the possible pathogenesis and report the postoperative results of the late tricuspid regurgitation (TR) after left cardiac valve replacement. Methods: 56 patients developed severe TR after left cardiac valve replacement, including 10 patients with normal prosthesis valve function (group A) and 46 patients with prosthesis valve dysfunction (group B). Four patients underwent mitral valve replacement (MVR) and 6 patients underwent mitral and aortic valve replacement (DVR) in group A. In group B, 36 patients received MVR, 4 aortic valve replacement (AVR) and 6 DVR. Ten patients underwent tricuspid De Vega annuloplasty and 46 patients' tricuspid valves were normal during the initial operation. The surgical treatment of tricuspid valve included tricuspid valve replacement (TVR) in 9 and tricuspid valve plasty (TVP) in 47 at the second operation. Results: Two patients died postoperatively with hospital mortality of 3.6%. The 54 survivors were followed up from 6 to 132 months, mean 79.4 months. The heart function improved significantly in 8 after TVR and 40 after TVP. However, echocardiography showed moderate TR in 5 and severe TR in 1 patient after TVP and medical treatment was needed. Conclusion: The sustained pulmonary hypertension, irreversible right heart impairment, resumption of left ventricular function and sustained atrial fibrillation may be responsible for the development of late TR after left cardiac valve replacement. TVR may achieve a reliable result for severe functional TR and rheumatic tricuspid valve lesion. In some patients with TVP during the follow up, the TR might become more serious.