With the widespread adoption of low-dose CT screening and the extensive application of high-resolution CT, the detection rate of sub-centimeter lung nodules has significantly increased. How to scientifically manage these nodules while avoiding overtreatment and diagnostic delays has become an important clinical issue. Among them, lung nodules with a consolidation tumor ratio less than 0.25, dominated by ground-glass shadows, are particularly worthy of attention. The therapeutic challenge for this group is how to achieve precise and complete resection of nodules during surgery while maximizing the preservation of the patient's lung function. The "watershed topography map" is a new technology based on big data and artificial intelligence algorithms. This method uses Dicom data from conventional dose CT scans, combined with microscopic (22-24 levels) capillary network anatomical watershed features, to generate high-precision simulated natural segmentation planes of lung sub-segments through specific textures and forms. This technology forms fluorescent watershed boundaries on the lung surface, which highly fit the actual lung anatomical structure. By analyzing the adjacent relationship between the nodule and the watershed boundary, real-time, visually accurate positioning of the nodule can be achieved. This innovative technology provides a new solution for the intraoperative positioning and resection of lung nodules. This consensus was led by four major domestic societies, jointly with expert teams in related fields, oriented to clinical practical needs, referring to domestic and foreign guidelines and consensus, and finally formed after multiple rounds of consultation, discussion, and voting. The main content covers the theoretical basis of the "watershed topography map" technology, indications, operation procedures, surgical planning details, and postoperative evaluation standards, aiming to provide scientific guidance and exploration directions for clinical peers who are currently or plan to carry out lung nodule resection using the fluorescent microscope watershed analysis method.

Objective To analyze the long-term outcome of modified Morrow surgery (interventricular septal cardiomyectomy) in the treatment of hypertrophic obstructive cardiomyopathy (HOCM) in children. Methods The clinical data of the children with HOCM (aged≤14 years) who underwent modified Morrow surgery from January 2010 to August 2022 in Guangdong Provincial People&#39;s Hospital were retrospectively analyzed, including changes in hospitalization status, perioperative period, and long-term 15-lead electrocardiogram and echocardiography. Results A total of 29 patients were collected, including 22 males and 7 females, aged 10.00 (5.00, 12.00) years. Five (17.9%) patients had New York Heart Association (NYHA) heart function grade Ⅲ or Ⅳ. Ventricular septal cardiomyectomy was performed in all patients. All 29 patients survived and their cardiac function recovered after operation. Before discharge, right bundle branch block was observed in 2 patients and left bundle branch block in 6 patients. After surgery, in the left ventricular septal cardiomyectomy, the left atrial diameter decreased (P＜0.001), left ventricular end-systolic diameter increased (P=0.009), the peak pressure gradient of left ventricular outflow tract decreased (P＜0.001), and the thickness of ventricular septum decreased (P＜0.001). The systolic anterior motion of mitral valve disappeared and mitral regurgitent jet area decreased (P＜0.001). The flow velocity and peak pressure gradient of right ventricular outflow tract also decreased in the patients who underwent right ventricular septal cardiomyectomy. The average follow-up of the patients was 69.03±10.60 months. All the patients survived with their NYHA cardiac function grading Ⅰ or Ⅱ. No new-onset arrythmia event was found. Echocardiography indicated that the peak pressure gradient of the left ventricular outflow tract remained low (P<0.001). Moderate mitral regurgitation occurred in 2 patients, and left ventricular outflow tract obstruction with moderate mitral regurgitation occurred in 1 patient after simple right ventricular septal cardiomyectomy. Conclusion Right ventricular or biventricular obstruction is frequent in the children with HOCM and they usually have more symptoms before surgery. Modified Morrow surgery can effectively relieve outflow tract obstruction and improve their cardiac function. The long-term outcome is satisfactory. However, the posterior wall of the left ventricle remains hypertrophic. Also, there is an increased risk of a conduction block.

Mitral valve replacement is one of the most common heart valve surgeries in China. In recent years, with the increase in degenerative valve diseases, older patients, and the progress of anti-calcification technology of biological valves, the proportion of mitral valve biological valve replacement has been increasing year by year. After the damage of traditional mitral valve biological valves, re-operation of valve replacement with thoracotomy is required. However, the adhesion between the heart and sternum, as well as the damage caused by cardiopulmonary bypass and cardiac arrest, can cause significant trauma to elderly patients and those with multiple organ dysfunction, leading to increased mortality and complication rates. In recent years, interventional valve surgery, especially transcatheter valve-in-valve surgery, has developed rapidly. This procedure can correct the damaged mitral valve function without stopping the heart, but there are still many differences between its technical process and conventional aortic valve replacement surgery. Therefore, organizing and writing multicenter expert recommendations on the technical process of transcatheter valve-in-valve surgery for damaged mitral valve biological valves is of great significance for the training and promotion of this technology.

Objective To investigate the current situation and health effects of indoor microbial pollution in Xi&#39;an, to analyze the purification effect of air purifiers on indoor microbial pollution, and to provide reference for improving the indoor environment. Methods Through stratified random sampling, 20 families from rural areas and 20 families from upwind and downwind urban areas respectively were selected from Xi&#39;an. Data was collected by questionnaire surveys and on-site environmental sampling. Non-parametric analysis and correlation analysis were used for statistical analysis. Results Overall, the standard-exceeding rate of total count of bacteria was 5.00%. The medians of the total count of bacteria and fungi were 312.50 cfu/m3 and 260.00 cfu/m³, respectively. In terms of health effects, the correlation between rhinitis and cold with total bacterial count was statistically significant (P<0.05), with the correlation coefficients of 0.182 and 0.223, respectively. Purification effect of air purifiers on microbial pollution was statistically significant (P<0.05). After opening for 2 hours, the total numbers of bacteria and fungi decreased significantly. Conclusion The occurrence risk of colds and rhinitis is increased by indoor microbial pollution. Air purifiers have a certain effect on decreasing the total number of bacteria and fungi. It is recommended to use air purifiers with high CADR of particulate matter, double-layer filter and sterilization and dehumidification function, and replace the filters regularly to reduce indoor microbiological contamination.

We reported a 26-year-old male who was diagnosed with apical hypertrophic cardiomyopathy with left ventricular aneurysm. The location of the hypertrophic myocardium and the extent of resection were accurately assessed preoperatively using 3D modeling and printing technology. Myectomy was performed via transapical approach, and the intraoperative exploration was consistent with the description of the preoperative 3D modeling. The patient underwent the surgery successfully without any complications during the hospitalization, and the cardiopulmonary bypass time was 117 min, the aortic cross-clamping time was 57 min, and the hospital stay time was 7 d. The postoperative echocardiography demonstrated left ventricular cavity flow patency. This case provides a reference for the management of patients with apical hypertrophic cardiomyopathy.

Objective     To evaluate the early clinical outcomes of the Renatus® balloon-expandable valve in the treatment of severe aortic stenosis. Methods    From November 2021 to April 2022, a total of 38 patients who received Renatus® balloon-expandable valve for severe aortic stenosis in Guangdong Provincial People&#39;s Hospital were included. There were 22 males and 16 females, with an average age of 73.7±5.3 years. Mean aortic gradient and peak aortic jet velocity at baseline, post-procedure, and follow-up were compared. Clinical outcomes including all-cause mortality, perivalvular leakage, serious adverse cardiovascular events and the occurrence of permanent pacemaker implantation were assessed. Results    All patients completed the procedure successfully without conversion to thoracotomy or perioperative death. The post-implant mean aortic pressure gradient was decreased from 41.5 (27.8, 58.8) mm Hg to 6.0 (3.0, 8.0) mm Hg, and the peak aortic jet velocity was also decreased from 4.1±0.9 m/s to 1.7±0.4 m/s (P<0.001). Pacemakers were required in 2 (5.3%) patients. The median follow-up time was 27.5 (23.0, 87.5) d, with a follow-up rate of 100.0%. The mean aortic gradient was 8.0 (7.0, 10.8) mm Hg and peak aortic jet velocity was 2.0±0.3 m/s, showing significant improvement compared with those in the preoperative period (P<0.001). No severe aortic regurgitation or paravalvular leak was observed. There was no serious cardiovascular adverse event or reoperative event during the study period. Conclusion    Transcatheter aortic valve replacement with the domestic Renatus® balloon-expandable valve system is a safe and effective procedure for selected patients with severe aortic stenosis who are at high risk or not candidates for surgical aortic valve replacement.

Objective    To determine the clinical efficacy of transcatheter aortic valve replacement (TAVR) for severe aortic regurgitation (AR) combined with severe mitral regurgitation (MR). Methods    The clinical data of 13 patients who underwent TAVR due to severe AR combined with severe MR from March 2018 to September 2021 in our hospital were retrospectively analyzed, including 10 males and 3 females with a mean age of 72.54±2.35 years. The echocardiographic findings of all patients were compared preoperatively and postoperatively. Results    Surgeries were performed successfully in all patients without intraoperative death or conversion to sternotomy. The operation time was 118.15±11.42 min, intraoperative blood loss was 100.00 (75.00, 250.00) mL, and the length of hospital stay after surgery was 9.00 (4.50, 11.00) d. The mean follow-up duration was 10.00 (6.50, 38.50) months, during which there were 2 patients with mild to moderate AR, 6 with mild AR, and 5 with no AR; meanwhile, severe MR decreased significantly (P=0.001) even without active intervention, including 4 mild to moderate MR and 9 mild MR patients. Compared to preoperative indexes, the left atrial diameter [46.00 (41.00, 52.50) mm vs. 35.00 (34.00, 41.00) mm, P<0.001], left ventricular end-systolic diameter [45.00 (36.00, 56.00) mm vs. 35.00 (28.00, 39.00) mm, P=0.002] and left ventricular end-diastolic diameter (62.62±2.40 mm vs. 51.08±2.49 mm, P<0.001) showed a decreasing trend during the follow-up. Conclusion    In selected patients with severe AR combined with severe MR, TAVR alone improves AR and combined MR at the same time.

Objective     To evaluate the safety and efficacy of transcatheter aortic valve replacement (TAVR) using the SAPIEN 3 system. Methods    This was a prospective, multicenter, single arm study in 4 centers in China. The clinical data of 50 patients with high-risk symptomatic severe aortic stenosis who underwent TAVR using the SAPIEN 3 system from June 2017 to June 2019 were analyzed, including 27 males and 23 females aged 76.8±6.1 years. Results    The Society of Thoracic Surgeon score was 6.0%±2.8%. Totally, 20.0% of patients had severe bicuspid aortic stenosis. The operation time was 41.8±16.5 min and the hospital stay time was 8.5±5.0 d. At the postoperative 30-day follow-up, no all-cause mortality occurred and the device success rate was 89.5%. Major vascular complications occurred in one (2.0%) patient,  stroke in one (2.0%) patient, new pacemaker implantation in one (2.0%) patient, as well as coronary artery obstruction in one (2.0%) patient. There was no moderate or moderate/severe paravalvular leak. The aortic pressure gradient was decreased from 49.2±16.2 mm Hg before the operation to 12.4±4.6 mm Hg at the postoperative 30-day follow-up, and the valvular area was increased from 0.6±0.3 cm2 to 1.3±0.3 cm2 (P<0.01). Moreover, the New York Heart Association classification in 83.7% of the patients was improved during the follow-up. Conclusion    This pre-marketing multicenter study has demonstrated the safety and effectiveness of transfemoral TAVR with the SAPIEN 3 transcatheter valve system in Chinese aortic stenosis patients at high risk for surgery.

An 81-year-old male patient was admitted to Guangdong Provincial People&#39;s Hospital due to chest distress and shortness of breath after activity for half a year. Examination after admission revealed severe aortic insufficiency, tricuspid aortic valve and extremely horizontal aorta with an aortic root angulation of 99°. The Society of Thoracic Surgeons score was 7%. And taking the strong demand of the patient and his family into consideration, we decided to perform transapical transcatheter aortic valve replacement after multidisciplinary evaluation. The procedure was successfully performed by means of low deployment land zone and traction of pre-exist Prolene suture. Three-month follow-up confirmed the normal function of aortic prosthetic valve without residual regurgitation. This case provides a reference for the interventional treatment in patients with extremely horizontal aorta.

Objective    To determine the clinical efficacy of transapical transcatheter mitral valve-in-valve treatment for patients with deteriorated mitral bioprosthesis after aortic-mitral double valve replacement. Methods    The clinical data of 9 patients who underwent transapical transcatheter mitral valve-in-valve implantation after aortic-mitral double valve replacement due to mitral bioprosthesis deterioration from May 2020 to January 2021 in our hospital were retrospectively analyzed, including 4 males and 5 females with a mean age of 72.44±7.57 years. Results    Surgeries were performed successfully in all patients with no conversion to median sternotomy. The mean procedural time was 101.33±48.49 min, the mechanical ventilation time was 23.11±26.54 h, the ICU stay was 1.89±1.05 d and the postoperative hospital stay was 6.11±2.02 d. Residual mild mitral regurgitation was only observed in 1 patient. Only 1 patient needed postoperative blood transfusion. No major complications were observed in all patients. There was no death in postoperative 90 days. Conclusion    For patients with deteriorated mitral bioprosthesis after aortic-mitral double valve replacement, transapical transcatheter mitral valve-in-valve implantation achieves good clinical results and effectively  improves the hemodynamics without increasing the risk of postoperative left ventricular outflow tract obstruction. The surgery is feasible and effective.