Thoracoscopic mitral valve replacement is a common minimally invasive cardiac surgery procedure. However, small annulus, severe calcification of the annulus, and severe thickening of the posterior valve leaflet or sub valvular structure are the difficulties of thoracoscopic mitral valve replacement. Improper treatment can easily lead to left ventricular rupture or prosthesis-patient mismatch. This paper reports a thoracoscopic mitral bioprosthesis replacement case using the chimney technique in Guangdong Provincial People's Hospital and summarizes its operating key points. The patient was a 68-year-old female, weighing 36 kg. The preoperative diagnosis was rheumatic mitral stenosis and atrial fibrillation, the preoperative transthoracic echocardiogram showed the left ventricular end-diastolic diameter was 39 mm. The surgical effect was satisfactory. The patient was in good condition at the follow-up 2 months after the operation.

Objective The CRISPR/Cas9 system was utilized to generate an Apoe knockout mice model to support further investigations of the role of Apoe in lipid metabolism and atherosclerosis.Methods Two single guide RNAs designed for Apoe in C57BL/6J mice were co-injected with Cas9 mRNA into fertilized eggs,followed by transplantation into ICR recipient mice to obtain F0 generation mice.KO mice were identified by polymerase chain reaction(PCR)screening of tail DNA.Apoe mRNA expression in various tissues was assessed by quantitative real-time PCR and lipid indexes were measured in serum samples.Lipid accumulation in the inner lining of aortic vessels was detected by oil red O staining.Results PCR and sequencing confirmed the successful construction of Apoe KO mice(C57BL/6-Apoeem1/Nifdc).Apoe mRNA levels were significantly reduced in the liver,brain,spleen,kidney,and lung tissues of Apoe KO homozygous mice(Apoe-/-),as shown by reverse transcription quantitative real-time PCR.Serum total cholesterol and low-density lipoprotein cholesterol levels were increased in Apoe-/-mice,and high-density lipoprotein cholesterol levels were decreased in male Apoe-/-mice.Extensive lipid plaques were observed in the inner lining of the arteries in Apoe-/-mice compared with WT mice,under normal chow consumption conditions.Conclusions This study successfully established an Apoe KO mice model exhibiting a typical abnormal lipid metabolism phenotype with arterial lipid accumulation,even without a high-fat diet intervention.This work provides background data for the Apoe KO mice resource and a new model for the study of abnormal lipid metabolism.

Objective We generated ob mice(C57BL/6N-Lepem1/Nifdc)with Lep gene knockout(ob/ob)using the CRISPR/Cas9 system,to establish a suitable animal model for preclinical drug evaluation for clinical diseases such as diabetes.Methods According to the principle of CRISPR/Cas9 target design,single guide RNA targeting the mouse Lep gene was designed for transcription in vitro,and microinjected with Cas9 mRNA into mouse zygotes.Mouse tail DNA was extracted and detected by polymerase chain reaction and sequencing,followed by mating of positive and wild-type mice.Blood biochemistry and liver pathology were assessed in homozygous ob mice.Results Eight positive mice were identified and a stable mouse strain was selected for further breeding.Serum triglycerides,total cholesterol,and alanine aminotransferase levels were significantly higher in homozygous ob mice than in wild-type mice,and liver pathology showed inflammatory infiltration and lipid vacuolar transformations.Conclusions We successfully established a Lep gene knockout mouse model,which will provide an important addition to the national rodent experimental animal database and an animal model for preclinical drug evaluation.

Objective The CRISPR/Cas9 system was utilized to generate an Apoe knockout mice model to support further investigations of the role of Apoe in lipid metabolism and atherosclerosis.Methods Two single guide RNAs designed for Apoe in C57BL/6J mice were co-injected with Cas9 mRNA into fertilized eggs,followed by transplantation into ICR recipient mice to obtain F0 generation mice.KO mice were identified by polymerase chain reaction(PCR)screening of tail DNA.Apoe mRNA expression in various tissues was assessed by quantitative real-time PCR and lipid indexes were measured in serum samples.Lipid accumulation in the inner lining of aortic vessels was detected by oil red O staining.Results PCR and sequencing confirmed the successful construction of Apoe KO mice(C57BL/6-Apoeem1/Nifdc).Apoe mRNA levels were significantly reduced in the liver,brain,spleen,kidney,and lung tissues of Apoe KO homozygous mice(Apoe-/-),as shown by reverse transcription quantitative real-time PCR.Serum total cholesterol and low-density lipoprotein cholesterol levels were increased in Apoe-/-mice,and high-density lipoprotein cholesterol levels were decreased in male Apoe-/-mice.Extensive lipid plaques were observed in the inner lining of the arteries in Apoe-/-mice compared with WT mice,under normal chow consumption conditions.Conclusions This study successfully established an Apoe KO mice model exhibiting a typical abnormal lipid metabolism phenotype with arterial lipid accumulation,even without a high-fat diet intervention.This work provides background data for the Apoe KO mice resource and a new model for the study of abnormal lipid metabolism.

Objective We generated ob mice(C57BL/6N-Lepem1/Nifdc)with Lep gene knockout(ob/ob)using the CRISPR/Cas9 system,to establish a suitable animal model for preclinical drug evaluation for clinical diseases such as diabetes.Methods According to the principle of CRISPR/Cas9 target design,single guide RNA targeting the mouse Lep gene was designed for transcription in vitro,and microinjected with Cas9 mRNA into mouse zygotes.Mouse tail DNA was extracted and detected by polymerase chain reaction and sequencing,followed by mating of positive and wild-type mice.Blood biochemistry and liver pathology were assessed in homozygous ob mice.Results Eight positive mice were identified and a stable mouse strain was selected for further breeding.Serum triglycerides,total cholesterol,and alanine aminotransferase levels were significantly higher in homozygous ob mice than in wild-type mice,and liver pathology showed inflammatory infiltration and lipid vacuolar transformations.Conclusions We successfully established a Lep gene knockout mouse model,which will provide an important addition to the national rodent experimental animal database and an animal model for preclinical drug evaluation.

Objective To analyze the application of virtual reality technology and mixed reality techniques in our hospital before and during intraoperative evaluation of complicated congenital heart diseases .Methods Methods Retrospectively ana-lyze the clinical treatment, surgical decision-making, intraoperative and early prognosis of 11 children with complicated congen-ital heart disease assessed by virtual reality technology and mixed reality techniques.The time of operation was 34-121 min, CPB time was 26-101 min, the clamping time of aorta was 18-56 min.There was no operative death.Results All 11cases were assessed by virtual reality technology and mixed reality technology before surgery .Personalized surgical strategies were made based on the evaluation results.All patients had undergone operations successfully.Compared with traditional surgical methods, fewer surgical incisions and shorter operation time were required.And it improved the surgical results.Conclusion Virtual reality technology and mixed reality technology have a great advantage in preoperative and intraoperative evaluation of complex congenital heart diseases.They can optimize surgical strategies, shorten operation time, and reduce surgical trauma. They are worthy of further promotion and application in clinical practice.

Objective To evaluate the value of three-dimensional(3 D) printing technique in the diagnosis and treatment of complex congenital heart disease(CHD).Methods From March 2016 to February 2018,40 patients with complex CHD underwent heart CT scanning.The CT images were imported to Standard Template Library(STL) files after 3D reconstruction and then exported for 3D printing.The 3D printed models were then used for decision making and navigation during surgery.Results Thirty patients were indicated for surgical operation.Three patients underwent single ventricular repair,and biventricular repair were operated on 27 patients.The 3D printed models were quite in accordance with the actual anatomical findings in all the patients.And all the procedures carried on were exactly same as planned based on 3D printed model.Conclusion The 3D printing may help improve the diagnosis and treatment level in complex CHD.

Objective To evaluate the results of thoracic endovascular aortic repair (TEVAR) for chronic type B aortic dissection.Methods From September 2005 to January 2013,30 patients with chronic type B aortic dissection received TEVAR.All patients were followed for 2-90 months [mean (33 ±25) months].Results All of the procedures finally achieved technical success.However,during TEVAR,there were transient endoleaks in 8 patients including type Ⅰ endoleaks in 3 patients,type Ⅱ endoleaks in 5 patients and persistent endoleaks in 3 patients which are type Ⅳ endoleaks.Type Ⅰ and type Ⅱ endoleaks were successfully managed during the procedures.There was no mortality or major complication during the perioperative period.Three patients died during follow-up:one patient died of carcinoma of the colon and two patients died of the complications of secondary interventions related to aortic dissection.Totally there were seven patients receiving secondary interventions.The Kaplan Meier actuarial survival curve showed a 5-year survival rate of 87.9％ and the 5-year survival rate without secondary intervention was 72.8％.Conclusions Early and midterm results showed that TEVAR was effective in treating chronic type B aortic dissection.