The deepening of our understanding on the cardiac electrophysiology mechanism and the progress on cell transplantation technique have expanded our view in treating various kinds of cardiac diseases. Over the past few years literatures have reported many kinds of cell transplantation techniques for treating various types of bradyarrhythmias, such as complete heart block and sinoatrial node dysfunction, and impressive achievements have been made by far. This review discusses the advantages and flaws of the existing strategies and the future of biological pacemakers.

Valvular disease is a commonly seen heart disorder,valve replacement is an effective approach to treat valve disorders.Both the mechanic valves and bioprosthesis used now have their own defects,making it important for the cardio surgery field to develop some kind of ideal valves.With the development of tissue engineering techniques,the tissue engineering valves are thought to have great potential and bright clinical future,and now it has become a hot point in cardiac surgery.This article is to evaluate the frame materials,resource of tissue cells and implantation, in vitro pre adaptation testing and in vivo animal experiment results,and the existing problems are pointed out in the present study.

Chest wall resection and reconstruction remains a severe challenge for reconstructive surgeons,which often leads to conservative treatment regimens in clinical practice,consequently resulting in poor outcomes(high morbidity and mortality).In recent 20 years,advances in muscle flap surgery and availability of chest reconstructive prosthesis have encouraged the surgeons to take an active attitude toward chest wall resection;many "unresectable" lesions now have a chance to be resected and cured.This article reviews the problems concerning the principles for chest wall resection,reconstruction,prosthesis selection,etc.in chest wall reconstruction.

Objective To report the outcome of surgical treatment of prosthetic valve endocarditis (PVE). Methods From 1990 to Aug 2003, 21 patients with PVE were operated on, including 5 acute PVE and 16 subacute PVE. Blood culture was positive in 13 cases. Echocardiographic findings showed aortic and mitral valve leakage in 6 and 3 cases respectively. Aortic and mitral vegetation was found in 3 and 5 cases, respectively. Mechanical valve was used to replace mitral valve in 11 cases, aortic valve in 10 cases. Ascending aortic false aneurysm was resected, and ascending aorta repaired in one case. Vegetations were found in all cases, mitral annulus abscess in 7 cases and myocardial abscess in 3, aortic annulus abscess in 8 and myocardial abscess in 4. Results There were 5 early-death, 3 due to recurrence of infection, 2 due to multiorgans failure. One late death was due to fungus infection. The survivors were followed up from 4 months to 13 years, one case had recurrence of PVE and died after ineffective medical treatment. Conclusion Early diagnosis of PVE, optimal timing of surgery, radical debridement of infected tissue, and utilizing sensitive and high dose of antibiotics perioperatively, are the key factors to improve the surgical outcome.

Objective To investigate the application of a novel degradable biomaterial artificial chest wall as a chest wall prosthesis and explore the feasibility of its use in chest wall reconstruction. Methods A full-thickness chest wall defect of 10?10 cm was created in 8 dogs and then repaired with short chitin fiber reinforced polycaprolactone (PCL) plate. The situation of the implanted chest wall prosthesis and the progress of the regeneration of the chest wall tissue were observed dynamically postoperatively by X-ray, CT and histological examinations. Results No operative and peri-operative deaths were observed, no flail chest and paradoxical movement, no infection and severe complications occurred. Artificial chest wall prosthetic integrated tightly with chest wall ribs and muscle tissue around. New bone tissue obviously regenerated around both resection ends of the ribs in 4 months. The chest wall prosthesis was tightly enveloped by thick fibrous tissue in 6 months. Conclusion Degradable chitin fiber reinforced PCL biomaterial has excellent properties such as fine biocompatibility, optimal mechanical properties, fine flexibility and elasticity and translucent to X-rays. It is a prospective material for chest wall reconstruction.

Objective To summarize the methods and experiences of aortic arch surgery. Methods In 75 aortic arch operations, 74 were performed by using deep hypothermic circulatory arrest (DHCA), including retrograde cerebral perfusion (RCP) in 54 cases and antegrade selective cerebral perfusion (SCP) in 20 cases. Surgical procedures included ascending aortic and hemiarch grafting in 53 cases, which concomitantly included stent placement intra decending aorta in 11, patching of arch intimal tear in 6 and of decending aortic one in 3. Ascending and total arch grafting in 20 cases,which concomitantly included traditional elephant trunk procedure in 12 and stent placement intra decending aorta in 4. Simple arch aneurysm resection in 1 and arch grafting in 1. Concomitant procedures included Bentall procedure in 17 cases, AVR in 12, Cabrol procedure in 3, mitral valvuloplasty in 5 and aortic valvuloplasty in 9. DHCA time ranged from 9 to 120 min (mean 42.3 min). Results Operative mortality was 6.7%. The most common complications were respiratory insufficiency(11 cases), renal insufficience(7 cases) and temporary mental anomaly(9 cases). Conclusion DHCA+RCP and DHCA+SCP are both effective while the latter is more suitable for complex aortic arch surgery. The choice of surgical procedures depends on the nature of lesion and location of intimal tear. Preoperative condition and surgical technique are the essential factors to success in aortic arch surgery.

Objective To investigate the long-term morphologic and functional changes of the tricuspid valve after mitral valve replacement. Methods The tricuspid valve function was evaluated by Doppler echocardiography in 903 patients who underwent mitral valve replacement during recent 10 years. Tricuspid regurgitation and annular dilatation in various degrees were found in all patients preoperatively. 686 patients underwent Kay annuloplasty or DeVega annuloplasty, 106 patients underwent tricuspid ring annuloplasty, and 201 untreated. Results Among 201 patients who did not undergo tricuspid annuloplasty, severe tricuspid regurgitation developed in 46 during 2 to 3 years follow-up. One out of 16 patients who underwent tricuspid ring annuloplasty developed moderate tricuspid regurgitation 2 years after operation. Of 686 patients who underwent Kay annuloplasty or DeVega annuloplasty, 150 developed moderate or severe tricuspid regurgitation during 3~5 years after operation. Conclusion Tricuspid annular dilatation, right heart impairment and severe pulmonary hypertension are responsible for the development of late tricuspid regurgitation after mitral valve replacement. For the patient who underwent mitral valve replacement ,tricuspid annuloplasty should be performed when annular dilatation was found, even without tricuspid regurgitation and tricuspid ring annuloplasty should be performed in patient with severe tricuspid regurgitation and obvious tricuspid annular dilatation.

Objective: To determine whether paroxetine would be effective in the treatment of patients with chronic insomnia and to compare efficacy of paroxetine and estazolam on chronic insomnia. Methods: 74 patients with chronic insomnia were divided into 2 groups, receiving treatments of paroxetine and estazolam respectively. All of the subjects were assessed with Pittsburgh Sleep Quality Index (PSQI) and sleep diary. Results: 1. On the eighth day of treatment, estazolam group showed improvement, all the indexes of sleep were better than those before treatment and those of paroxetine group; 2. On the fifteenth day of treatment, paroxetine group showed improvement, all the indexes of sleep were better than those before treatment and those of estazolam group, while the indexes of the estazolam group returned to pre-treatment level. 3. At the end of treatments and 3 months' follow up, paroxetine group still showed better effect in sleep indexes than estazolam group and the pre-treatment level. Conclusion: paroxetine is effective in the treatment of chronic insomnia and shows long-term effect.

Objective To design and prepare a new prosthesis of chest wall by selecting and integrating the appropriate biodegradable materials,and to evaluate the efficiency and safety of the prepared prosthesis in order to explore the feasibility of reconstruction of an extensive chest wall defect.Methods Three types of chest wall prostheses,polydioxanone(PDO)mesh,chitin fiber reinforced polycaprolactone(CFRP)plate and CFRP strip,were designed and prepared to fulfill the function of chest wall.A canine model of the chest wall resection and reconstruction was reproduced to evaluate these porstheses.15 adult mongrel dogs were subjected to extensive resection of anterior-lateral chest wall and reconstruction with chest wall prosthesis.Chest wall stability,the degradative process of the prosthetic materials and regeneration of the chest wall tissue postoperatively were recorded dynamically by macroscopic inspection and histopathologic examinations,so as to provide valuable scientific data for improving chest wall prosthesis.Results The implanted PDO mesh was well integrated with autogenous connective tissue 8 weeks after operation,degraded gradually and reabsorbed completely within 24 weeks.It provided adequate support to the chest wall and achieved satisfy cosmetic and functional repair.CFRP plate was the best in chest wall stabilization among the three groups,and paradoxical respiratory movement was efficiently relieved with CFRP rib,and it had a better biological compatibility.There was no obvious morphological change in the CFRP material after it was implanted for 24 weeks.Conclusion The synthetic prostheses developed here showed excellent biocompatibility,and they fulfilled the function in providing chest wall stabilization.Each prosthesis has its respective favorable properties in chest wall reconstruction,and all of them are valuable in clinic application in the management of complicated chest wall defects.

Objective To evaluate the therapeutic efficacy of peritoneal dialysis(PD) for acute renal failure(ARF) subsequent to cardiac surgical procedures in adults.Method Clinical data of 125 consecutive adult patients,admitted from Feb.1997 to Nov.2007,with ARF subsequent to cardiac surgery and undergone PD,were analyzed retrospectively.The levels of creatinine(Cr),blood urea nitrogen(BUN),albumin and kalium ion([K+]) were compared before and after PD.Results Of 8451 consecutive adult patients undergone operations on heart,358 cases(4.2%) experienced ARF,and 125 cases(1.5%) required PD.In 117 patients performed PD,[K+] declined to normal level within one day,BUN and Cr were 10.5?3.6mmol/L and 129.3?41.6?mol/L at the third day after PD respectively,significantly lower than those before PD(P