Objective:To fundamentally solve the problems of valve dysfunction caused by limited size of artificial valve, high requirements for implantation technology, destruction of subvalvular structure and proliferation of fibrous endothelial tissue. We have developed a prosthetic valve with zero left ventricular occupancy. The valve frame is appropriately higher than the existing products, slightly chimney shaped, fully accommodates the movement of the valve leaves in the valve frame, and completely supraannular surgical implantation. This study uses this valve for preclinical animal test.Methods:Seven sheep underwent the replacement of the artificial valve under the direct vision of cardiopulmonary bypass. Warfarin was used for anticoagulation for 6 months 24 hours after operation. The blood biochemistry, anticoagulation and cardiac color Doppler ultrasound were detected after operation. The sheep were killed 180 days later for autopsy to observe whether the artificial valve caused thromboembolism. The efficacy and safety of valve were observed.Results:Two of the seven sheep died within 24 hours after operation, and five survived for a long time. Later, they were killed at 180 days. The mechanical properties of the artificial valve were good, and there was no thromboembolism around the artificial valve and important organs. The tissue layer of suture ring has been completely organized and endothelial cells, and the thickness of tissue layer is about 0.6-1.0 mm. The mitral valve of experimental animals can be opened and closed freely, with smooth surface and no abnormal echo. The follow-up of color Doppler ultrasound showed that the left ventricular ejection fraction was normal (0.60-0.70) before and 6 months after operation. The results of cross valve pressure difference and blood flow velocity of artificial valve were good (vmean was far lower than 5 mmHg(1 mmHg=0.133 kPa) and pmean was lower than 1 m/s) , suggesting that the hemodynamic performance of artificial valve was good. Left ventricular retrograde angiography showed that the artificial valve was completely located in the left atrium with good position and normal opening and closing. There was no obvious perivalvular leakage and other abnormalities. Within 7 days of blood test, the indexes of surgical stress were more abnormal than those before operation. At 12 and 24 weeks, there were no obvious abnormalities in blood routine test, liver and kidney function and other blood test indexes of animals in each group.Conclusion:The new chimney shaped mechanical valve implanted completely above the mitral annulus has good wear resistance, histocompatibility, antithrombotic and hemodynamic performance.

Objective:To introduce the early results of total aortic arch replacement (TAA) without cardiopulmonary bypass (CPB) and without interruption of cerebral blood supply, using the technique of arch branches preferential reconstruction and whole brain perfusion for brain protection.Methods:Between June 2020 and March 2021, a total of 9 Stanford type A aortic dissection patients we performed total arch replacement by using the technique of arch branches preferential reconstruction and whole brain perfusion without cardiopulmonary bypass and without interruption of blood supply to the brain. The method of this reconstruction technique is as follows: A 24F aortic cannula was inserted into the true lumen at the root of the transverse innominate artery (IA) to connect one end of the artery for cardiopulmonary bypass. The access was connected to 14F artery via Y-connector and inserted into IA cavity to maintain blood supply to brain. Without cardiopulmonary bypass, the 10 mm branch of the four branch artificial blood vessel was anastomosed with the innominate artery IA. The perfusion collateral was connected to the second end of the artery of CPB (single pump and double tubes) to continue to supply blood for IA. The left common carotid artery (LCA) and left subclavian artery (LSCA) were reconstructed by the same method. When IA and LCA were anastomosed, the distal blood supply was not interrupted. After the three branches of the aortic arch were anastomosed, we started to turn the machine, then cooled down and blocked the ascending aorta to further complete the operation of the aortic root and arch. During the period of lower body circulatory arrest, the whole brain was perfused with low flow.Results:No intraoperative death or perioperative complications occurred in all patients, and they were discharged smoothly. The cardiopulmonary bypass time was (192.4±58.1) min, the aortic clamping time was (128.3±52.4) min, the lower body circulatory arrest time was (29.1±1.3) min, and the postoperative awake time was (8.2±3.7) h.Conclusion:Off-pump arch branches preferential reconstruction can provide physiological whole brain perfusion, shorten the cardiopulmonary bypass time and aortic occlusion time, and the operation is safe and effective.

Bone homeostasis is a relative balance between bone formation and resorption. Signal transducer and activator of transcription 3 (STAT3), which is closely related to bone homeostasis, takes part in multiple intracellular and extracellular signal pathways. STAT3 participates in the process of osteoblast differentiation regulated by several factors. It can also maintain bone homeostasis by regulating the recruitment, differentiation and activation of osteoclasts. In addition, STAT3 is involved in the interaction between osteoblasts and osteoclasts. Patients with STAT3 mutations can have several inherited bone metabolism diseases. Furthermore, STAT3 plays a critical role in load-driven bone remodeling. Mechanical stimulation promotes osteoblast differentiation and bone formation through activating or enhancing STAT3 expression during bone remodeling process. This review summarizes the participation of STAT3 in maintaining bone homeostasis together with its possible mechanisms and discusses the connection between STAT3 and mechanical stimulation in bone remodeling, so as to provide a potential pharmacological target for the treatment of bone diseases.

Depression is a common psychiatric disorder, and approximately 30% patients with depression do not respond effectively to standard antidepressant medication; this condition is termed treatment resistant depression (TRD) and its neurobiological mechanism remains unclear. Neuroimaging techniques can non-invasively explore changes in brain structure, function and metabolism. These techniques have been applied in neurobiological research of TRD and revealed critical abnormalities in brain structure, function and metabolism in fronto-limbic system. In this paper, we reviewed the latest progress in neuroimaging researches on TRD, providing new insight and imaging evidence for further neurobiological studies of TRD.

Objective To study the clinical significance of serum hs-CRP level in smokers with carotid atherosclerosis (CA) and analyze its difference in subtypes of CA.Methods Two hundred and ninety-eight smokers with CA served as a smoker group and 120 non-smokers with CA served as a non-smoker group,50 healthy smokers without CA served as control group 1 and 50 healthy non-smokers served as control group 2.Their serum hs-CRP level was measured by colloid-enhanced immunoturbidimetry.Smokers were divided into stable plaque group and unstable plaque group.Effect of smoking on serum hs-CRP level in CA patients was analyzed.Results The serum hs-CRP level was significantly higher in smoker group and control group 1 than in non-smoker group and control group 2 (7.26±4.24 mg/L vs 3.56±2.28 mg/L,4.34±2.74 mg/L vs 3.17± 1.68 mg/L,P＜0.05).The smoking index was positively related with the serum hs-CRP level (r=0.395,P＜0.01).The number of daily smoked cigarettes was significantly greater in unstable plaque group than in stable plaque group (P＜0.05).The recurrence rate of ischemic stroke was significantly higher in smokers with a high serum hs-CRP level than in those with a low serum hs-CRP level (11.36％ vs 2.00％,P＜0.01).Conclusion Smoking can increase the serum hs-CRP level in CA patients,which is closely related with the stability of plaques and the recurrence of ischemic stroke.

Objective To summarize the experience with resurgery for recurrent valvular heart diseases.Methods From June 2004 to June 2015, 28 patients (15 males and 13 females) with ages ranging from 44 to 67 years (55.6±6.5 years) with recurrent heart valve disease underwent resurgery. The reasons for resurgery included perivalvular leakage (7 cases), bioprosthetic valve decline (6 cases in mitral valve and 3 in tricuspid valve), mechanical prostheses dysfunction (2cases), infective endocarditis after valve replacement (2 cases), restenosis of repaired native valve (1 case), and severe tricuspid insufficiency after left-side valve surgery (7 cases). Resurgery included mitral valve replacement in 18 patients and tricuspid valve replacement in 10. All the patients underwent third or fourth or even fifth cardiac surgery for valve replacement.Results There were 2 hospital deaths with a mortality of 7.1% (2/28). The main causes of early-stage deaths were low cardiac output syndrome. The main postoperative complications were respiratory failure in 3, low cardiac output syndrome in 2, reexploration for bleeding in 2 and serious infectious shock in 1. All the patients were found with the great improvement in heart function and the re-implanted prostheses worked well during follow-up.Conclusions Although resurgery for recurrent heart valve disease poses a continuing challenge to cardiac surgeon, it could be performed with the satisfactory results. The keys to a successful cardiac resurgery include appropriate operational timing, refined surgical technique and reasonable perioperative managements.

BACKGROUND:Our preliminary study found that the monocusp valves made of ultramicropore expanded
polytetrafluoroethylene (ePTFE) revealed no significant thrombus, calcification, or degradation 20 weeks after implanted into the descending aorta and the left pulmonary artery in sheep, which verified the good property of ePTFE. However, the surface of ePTFE in the left pulmonary artery was covered with obvious neointima.
OBJECTIVE: To assess the biocompatibility of phosphorylcholine-coated ePTFE.
METHODS:ePTFE surface was modified by phosphorylcholine derivative. Then the changes of surface shape, tensile stress at yield and elasticity modulus, water contact angle, and protein absorption capacity of ePTFE after surface modification were observed. (1) Hemolytic test: the leaching solution of phosphorylcholine-coated ePTFE, leaching solution of uncoated ePTFE, normal saline, and distiled water were added to the diluted human blood, respectively. (2) Platelet count test: the phosphorylcholine-coated ePTFE, uncoated ePTFE, high density
polyethylene, and Zymosan A were added to the whole blood samples from healthy volunteers, respectively.
(3) Platelet activation test: the phosphorylcholine-coated ePTFE, uncoated ePTFE, γ-Globulins, and Zymosan A
were added to the whole blood samples from healthy volunteers, respectively.
RESULTS AND CONCLUSION: The mean micropore diameter of ePTFE was significantly decreased after
phosphorylcholine coating (P < 0.001). The hydrophilicity and the ability of suppressing protein adsorption were
significantly strengthened after phosphorylcholine coating (P < 0.001). Phosphorylcholine coating did not influence
ePTFE in biomechanical properties and hemolytic test. The platelet count test and platelet activation test demonstrated that phosphorylcholine coating significantly improved anti-thrombus function of ePTFE. So, phosphorylcholine coating can enhance anti-thrombus function, suppress protein adsorption, and improve biocompatibility of ePTFE.

OBJECTIVETo investigate the role of left atrial appendage (LAA) closure for cerebral ischemic stroke prevention following mitral valve replacement.

METHODSRetrospective data on 860 consecutive adult patients undergoing mitral valve replacement between January 2008 and January 2013 were analyzed. There were 414 male and 446 female patients, with a mean age of (53 ± 12) years. The patients were divided into two groups according to whether the left atrial appendage was closed during operation: LAA closure group (n = 521) and non-LAA closure group (n = 339).Early mortality, postoperative cerebral ischemic stroke and the risk factors for cerebral ischemic stroke were assessed. Multivariate analysis was performed using logistic regression analysis.

RESULTSCompared with non-LAA closure group, LAA closure group had higher proportion of female gender, higher percentage of patients with cardiac insufficiency, pulmonary hypertension and left atrial thrombus, higher incidence of mechanical valve implantation and concurrent tricuspid surgery, and larger preoperative diameter of left atrium, but lower proportion of hypertension and patients undergoing coronary artery bypass surgery, and shorter aorta cross clamping time (χ² = 6.807 to 122.576, t = -2.818 and 3.756, all P < 0.05). There were no differences in exploratory thoracotomy for bleeding and in-hospital mortality between the two groups. Postoperative cerebral ischemic stroke occurred in 12 patients (1.4%). The incidence of cerebral ischemic stroke in LAA closure group was significantly lower than in non-LAA closure group (0.6% vs.2.7%, χ² = 6.452, P = 0.011).Logistic regression analysis showed that LAA closure was a significant protective factor for postoperative cerebral ischemic stroke (OR = 0.189, 95% CI: 0.039 to 0.902, P = 0.037) while history of cerebrovascular disease (OR = 4.326, 95% CI:1.074 to 17.418, P = 0.039) and preoperative diameter of left atrium (OR = 1.509, 95% CI: 1.022 to 1.098, P = 0.002) being the independent risk factors for postoperative cerebral ischemic stroke. The subgroup analysis showed that, for atrial fibrillation patients, LAA closure was a strong protective factor (OR = 0.064, 95% CI: 0.006 to 0.705, P = 0.025), but LAA closure was not a significant predictive factor (OR = 1.902, 95% CI: 0.171 to 21.191, P = 0.601) in non-atrial fibrillation patients.

CONCLUSIONConcurrent LAA closure during mitral valve replacement is safe and effective to reduce the early postoperative risk of cerebral ischemic stroke in atrial fibrillation patients.

Adult ; Aged ; Atrial Appendage ; surgery ; Atrial Fibrillation ; Brain Ischemia ; complications ; prevention & control ; Coronary Artery Bypass ; Female ; Heart Valve Prosthesis Implantation ; Hospital Mortality ; Humans ; Incidence ; Male ; Middle Aged ; Mitral Valve ; Mitral Valve Insufficiency ; surgery ; Nervous System Diseases ; Retrospective Studies ; Risk Factors ; Stroke ; prevention & control ; Thrombosis

OBJECTIVETo analysis the influence of surgical revascularization on different timing after ST-elevation myocardial infarction (STEMI) on patients with coronary artery disease and left ventricular dysfunction.

METHODSClinical data of 225 patients admitted from January 2003 to July 2012 with history of STEMI and left ventricular dysfunction (ejection faraction<50%) who underwent isolated coronary artery bypass grafting was retrospectively reviewed. There were 186 male and 39 female patients. According to the timing of surgical revascularization after STEMI, the patients were divided into early revascularization group (ER group, <21 days), mid-term revascularization group (MR group, 21 to 90 days) and late revascularization group (LR group, >90 days). There were 20 male and 9 female patients in ER group with mean age of (63 ± 10) years, 48 male and 16 female in MR group with mean age of (63 ± 8) years, 118 male and 14 female in LR group with mean age of (62 ± 10) years, respectively. Thirty-day post-operative mortality and major complications were determined as the endpoints to evaluate the early results of operation.

RESULTSThe 30-day post-operative mortality were 3.4%,0 and 2.3% among three groups respectively and there was no statistic difference between groups (χ(2) = 2.137, P = 0.330).Low cardiac output syndrome mortality were 13.8%, 3.1% and 2.3% among three groups respectively and there was statistic difference between groups (χ(2) = 8.344, P = 0.015). The ejection fractions was significantly improved in all the three groups from 42% ± 6%, 41% ± 6% and 42% ± 6% preoperatively to 46% ± 7%, 45% ± 10% and 45% ± 9% postoperatively (t = -3.378 to -2.339, all P < 0.05). The left ventricular end diastolic dimension were significantly reduced in MR group and LR group from (54 ± 6) mm and (55 ± 6) mm preoperatively to (47 ± 8) mm and (49 ± 9) mm postoperatively (t = 5.634, 5.885; P = 0.000). There was no significant change in ER group pre- and postoperatively ((51 ± 6) mm vs.(49 ± 7) mm, t = 1.524, P = 0.133).

CONCLUSIONSThe patients with coronary artery disease and left ventricular dysfunction can benefit from surgical revascularization on different timing after STEMI, presenting as the reverse of left ventricle remodeling and the improvement of left ventricle function. The short-term results are mainly determined by the patients' condition, surgical technique and the level of perioperative management.It is recommended for this patient cohort to accept surgical revascularization three weeks after STEMI.

Aged ; Cardiovascular Diseases ; Coronary Artery Bypass ; Coronary Artery Disease ; surgery ; Coronary Disease ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; surgery ; Myocardial Ischemia ; Retrospective Studies ; Time Factors ; Ventricular Dysfunction, Left ; Ventricular Function, Left