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We evaluated the feasibility and effectiveness of the right vertical sub-axillary incision used for the closure of ventricular septal defect. 100 patients (55 males and 45 females) who consecutively underwent surgical repair of their ventricular septal defect at our institution from January 2020 to November 2021 were retrospectively reviewed. Technique considerations were right thoracotomy with a vertical mid-axillary line mini-incision, and central cannulation for cardiopulmonary bypass. Median age was 13 months; median weight was 8.7 kg. The mean cardiopulmonary bypass time and aortic cross-clamp time were 67 ± 16 minutes, 51 ± 15 minutes respectively. The ICU stay was 2.2 ± 1.2 days, mechanical ventilation time was 12.9 ± 28.2 hours, postoperative hospital stays was 9.9 ± 4.9 days. Morbidities were pneumonia (20%); surgical site infection (3%); subcutaneous emphysema (44%); transient arrythmias (10%). There was no conversion to another approach. There was no early or mid-terms mortality with a mean follow up of 15.8 ± 5.2 months. All patients are in a good health status. No significant residual defects were found on their last follow-up echocardiography. In conclusion, the ventricular septal defect’s closure via right thoracotomy at Vietnam National Children’s Hospital is a safe and feasible procedure with excellent cosmetic results.

Background: This study evaluates mortality and intermediate outcomes of the arterial switch operation (ASO) for transposition or Taussig-Bing anomaly with single sinus coronary artery (CA) anatomy in a high-volume cardiac program in Vietnam. Methods: We retrospectively reviewed and performed risk factor analysis pertaining to 41 consecutive patients who presented with single sinus CA anatomy and who underwent ASO from January 2010 to December 2016 in our center. Results: The median age at operation was 43 days [interquartile range (IQR): 20-65] and the median weight was 3.6 kg (IQR: 3.4-4.0). Four in-hospital deaths (9.8%), of which one was related to coronary insufficiency. There were no late deaths, with a median follow-up time of 7.2 years. Survival for all patients with single sinus CA was 90.2% at 1 year and remained constant at 5 years and 10 years after ASO. The presence of a coexisting aortic arch anomaly was the only risk factor for overall mortality identified in this study (hazard ratio: 8.66, P = .031, 95% confidence interval: 1.21-61.92). There were three cardiac reoperations. Freedom from reintervention after ASO for patients with single sinus CA at 1 year, 5 years, and 10 years were 97.3%, 91.9%, and 91.9%, respectively. Interestingly, among all patients undergoing ASO during this time period (n = 304), single-sinus CA anatomy was not a risk factor for overall death ( P = .758). Conclusions: In a high-volume cardiac program in a lower middle-income country like Vietnam, ASO can be safely performed with single sinus CA anatomy, irrespective of the presenting coronary anatomy.

Pulmonary atresia with ventricular septal defect is a complex congenital heart defect whose management varies depending on the anatomy of pulmonary circulation and surgeon’s preferences. The surgical outcomes of complete repair in small infants and neonates in Vietnam have been seldomly reported. We reported our medium-term results of complete repair of this complex lesion using valved conduit in infants and neonates at our institution. The study included 25 patients with the body weight of less than 5kg who underwent definitive repair using valved conduit between January 2016 and December 2021. The median age at surgery was 66 days (IQR 45 – 116 days), and the mean body weight was 4 kg (3 – 5). Most (96%) attended all follow-up visits, and the average follow-up time was 37.4 months (8.4 – 69.3). There was 1 in-hospital death and 2 late mortalities. The 30-days and 5 years survival rate were 96% and 83%, respectively. One patient required conduit replacement at 3 years post operative because of conduit failure. The proportion of patients with freedom from conduit replacement at 5 years was 95%. Three cases required balloon dilatation of the left pulmonary artery due to stenosis. Freedom from all reinterventions and reoperations at 5 years was 52%. Definitive repair of this type of complex heart defect in small infants can be performed safely and resulted in good surgical outcomes.

Joint communications and sensing (JCAS) is envisioned as a key feature in future wireless communications networks. In massive MIMO-JCAS systems, hybrid beamforming (HBF) is typically employed to achieve satisfactory beamforming gains with reasonable hardware cost and power consumption. Due to the coupling of the analog and digital precoders in HBF and the dual objective in JCAS, JCAS-HBF design problems are very challenging and usually require highly complex algorithms. In this paper, we propose a fast HBF design for JCAS based on deep unfolding to optimize a tradeoff between the communications rate and sensing accuracy. We first derive closed-form expressions for the gradients of the communications and sensing objectives with respect to the precoders and demonstrate that the magnitudes of the gradients pertaining to the analog precoder are typically smaller than those associated with the digital precoder. Based on this observation, we propose a modified projected gradient ascent (PGA) method with significantly improved convergence. We then develop a deep unfolded PGA scheme that efficiently optimizes the communications-sensing performance tradeoff with fast convergence thanks to the well-trained hyperparameters. In doing so, we preserve the interpretability and flexibility of the optimizer while leveraging data to improve performance. Finally, our simulations demonstrate the potential of the proposed deep unfolded method, which achieves up to 33.5% higher communications sum rate and 2.5 dB lower beampattern error compared with the conventional design based on successive convex approximation and Riemannian manifold optimization. Furthermore, it attains up to a 65% reduction in run time and computational complexity with respect to the PGA procedure without unfolding., This paper has been submitted to Journal of Selected Topics in Signal Processing

In the karst regions of Vietnam, there are many different terrains. The most important one is karst polje. Because there are a lot of residential areas and important economic regions. Based on the study of Geomorphology, geological structure analysis, Geophysics document analysis, and karstification process research at Lang Son karst polje. The author gives conclusions: Lang Son karst polje was formed from the limestone of Bac Son Formation, 700 – 800 m thick. Lang Son karst polje was formed from anticline structure, the limestone of Bac Son Formation that has high karstification level. Lang Son karst polje has only one karst aquifer which is a water supply source for residential areas in Lang Son city. This karst aquifer distributes in limestone blocks of the Bac Son Formation. Geohazards on Lang Son karst polje include collapse, sinkhole, flood, and pollution of water. Among them, the most dangerous one is the collapse of the underground karst caves.

Objectives Aortopulmonary window (APW) associated with interrupted aortic arch (IAA) is a rare cardiac malformation with significant mortality and morbidity. This study aimed to report the intermediate outcomes of single-stage stage repair concentrating on the surgical techniques and postoperative reintervention for this rare cardiac lesion. Methods Eleven patients were diagnosed with IAA-associated APW and underwent single-stage surgical repair at Vietnam National Children’s Hospital. Results The APW anatomy types were the types I, II, and III in 1, 4, and 6 patients, respectively. The IAA morphology was type A in nine patients and type B in two patients. The median age was 27 (interquartile range [IQR] 6–79) days, and median weight was 3.5 (IQR 2.8–4.5) kg. The aortic arch was repaired using direct end-to-side tissue anastomosis in seven patients, and patch aortoplasty was performed in four patients. Six patients underwent APW closure with an intra-aortic baffle, and five patients required right pulmonary artery detachment and reimplantation. One early death occurred. Four patients required reinterventions: one patient required reoperation due to aortic stenosis and three required balloon angioplasty for either recurrent aortic arch stenosis (n = 1) or right pulmonary stenosis (n = 2) with a mean follow-up time of 3.1 (IQR 0.5–4.3 years). Conclusions Single-stage repair of IAA-associated APW can be achieved with good survival outcomes in children. However, the need for repeat reintervention or reoperation remains high, and the growth of both the aorta and pulmonary arteries should follow carefully with patient’s growth. Clinical registration number VNCH-RICH-18-96

The cytidine deaminases APOBEC3A and APOBEC3B (A3B) are prominent mutators of human cancer genomes. However, tumor-specific genetic modulators of APOBEC-induced mutagenesis are poorly defined. Here, we utilized a screen to identify 61 gene deletions that increase A3B-induced mutations in yeast. Also, we determined whether each deletion was epistatic with UNG1 loss, which indicated whether the encoded factors participate in the error-free bypass of A3B/Ung1-dependent abasic sites or suppress A3B-catalyzed deamination by protecting against aberrant formation of single stranded DNA (ssDNA). Additionally, we determined that the mutation spectra of A3B-induced mutations revealed genotype-specific patterns of strand-specific ssDNA formation and nucleotide incorporation across APOBEC-induced lesions. Combining these three metrics we were able to establish a multifactorial signature of APOBEC-induced mutations specific to (1) failure to remove H3K56 acetylation, which results in extremely high A3B-induced mutagenesis, (2) defective CTF18-RFC complex function, which results in high levels of A3B induced mutations specifically on the leading strand template that synergistically increase with loss of UNG1, and (3) defective HR-mediated bypass of APOBEC-induced lesions, which were epistatic with Ung1 loss and result from increased Rev1-mediated C-to-G substitutions. We extended these results by analyzing mutation data for human tumors and found BRCA1/2-deficient breast cancer tumors display 3- to 4-fold more APOBEC-induced mutations. Mirroring our results in yeast, for BRCA1/2 deficient tumors Rev1-mediated C-to-G substitutions are solely responsible for increased APOBEC-signature mutations and these mutations occur on the lagging strand during DNA replication. Together these results identify important factors that influence the dynamics of DNA replication and likely the abundance of APOBEC-induced mutation during tumor progression as well as a novel mechanistic role for BRCA1/2 during HR-dependent lesion bypass of APOBEC-induced lesions during cancer cell replication.

The development of the Fifth Generation (5G) New Radio (NR) provides several significant advantages when compared to the fourth generation (4G) Long Term Evolution (LTE) in mobile communications. Due to the outstanding characteristics of Low-Density Parity-Check (LDPC) codes such as high decoding performance, high throughput, low complexity, they have been accepted as the standard codes for the 5G NR. In this paper, we propose two LDPC decoding algorithms: Hybrid Offset Min-Sum (HOMS) and Variable Offset Min-Sum (VOMS), which are aimed at improving the error correction performance. The main idea of the HOMS/VOMS algorithm is to apply modified factors to both variable-nodes and check-nodes updated processing in order to compensate the extrinsic messages overestimation of the MS-based algorithms and increase the protection ability for degree-1 variable-nodes. The simulation results show that at the Bit-Error-Rate (BER) of 10-5, the proposed HOMS/VOMS algorithm achieves the decoding gain up to 0.2 dB compared to the Offset Min-Sum (OMS) algorithm, with a slight increase in decoding complexity.

One-bit digital-to-analog converters (DACs) are a practical and promising solution for reducing cost and power consumption in massive multiple-input multiple-output (MIMO) systems. However, the one-bit precoding problem is NP-hard and even more challenging in frequency-selective fading channels compared to the flat-fading scenario. While block-wise processing (BWP) can effectively address the inter-symbol-interference (ISI) in frequency-selective fading channels, its computational complexity and processing delay can be too high for practical implementation. An alternative solution to alleviate the processing complexity and delay issues is symbol-wise processing (SWP) which sequentially designs the transmit signals. However, existing SWP work leaves unwanted interference for later signal designs. In this paper, we propose an SWP approach which can efficiently address the ISI even at the symbol rate. The idea is to design the transmit signal to not only be beneficial for its time slot, but also to provide constructive interference for subsequent symbols. We develop two active ISI processing methods that significantly outperform a conventional approach, one of which that even outperforms the BWP approach at low SNR., 5 figures, conference

Cell-free massive MIMO is a promising technology for beyond-5G networks. Through the deployment of many cooperating access points (AP), the technology can significantly enhance user coverage and spectral efficiency compared to traditional cellular systems. Since the APs are distributed over a large area, the level of favorable propagation in cell-free massive MIMO is less than the one in colocated massive MIMO. As a result, the current linear processing schemes are not close to the optimal ones when the number of AP antennas is not very large. The aim of this paper is to develop nonlinear variational Bayes (VB) methods for data detection in cell-free massive MIMO systems. Contrary to existing work in the literature, which only attained point estimates of the transmit data symbols, the proposed methods aim to obtain the posterior distribution and the Bayes estimate of the data symbols. We develop the VB methods accordingly to the levels of cooperation among the APs. Simulation results show significant performance advantages of the developed VB methods over the linear processing techniques., 6 pages, 3 figures, conference

Mục tiêu: Nhận xét kết quả điều trị đóng xương ức thì hai ở bệnh nhi sau phẫu thuật tim mở tại Bệnh viện Nhi Trung ương. Đối tượng và phương pháp: Hồi cứu mô tả trên 61 bệnh nhi phẫu thuật tim mở và được đóng xương ức thì hai sau phẫu thuật từ tháng 5/2020 đến tháng 4/2021. Kết quả: Trong 61 bệnh nhân được nghiên cứu, tuổi trung vị là 2 (1 - 11,5) tháng, cân nặng trung vị là 4,5 (3,4 - 7,8) kg, thời gian đóng xương ức thì 2 trung bình là 46 giờ. Chỉ định để hở xương ức sau phẫu thuật chủ yếu do hội chứng cung lượng tim thấp (55,7%). Tỷ lệ thành công đóng xương ức là 60/61 bệnh nhân (98,4%). Tỉ lệ tử vong trong nhóm nghiên cứu là 13,1%. Các yếu tố nguy cơ ảnh hưởng tới tử vong có ý nghĩa thống kê bao gồm: Chỉ số lactat khi ra Khoa Hồi sức ngoại tim mạch, thời gian thở máy kéo dài, thời gian nằm hồi sức kéo dài, nhiễm trùng xương ức, nhiễm khuẩn huyết sau mổ, ECMO sau mổ. Kết luận: Đóng xương ức thì 2 là một phương pháp hỗ trợ hiệu quả đối với bệnh nhân có tình trạng huyết động không ổn định sau khi phẫu thuật tim mở phức tạp ở trẻ em trong giai đoạn hậu phẫu sớm.

Massive multiple-input multiple-output (MIMO) communications using low-resolution analog-to-digital converters (ADCs) is a promising technology for providing high spectral and energy efficiency with affordable hardware cost and power consumption. However, the use of low-resolution ADCs requires special signal processing methods for channel estimation and data detection since the resulting system is severely non-linear. This paper proposes joint channel estimation and data detection methods for massive MIMO systems with low-resolution ADCs based on the variational Bayes (VB) inference framework. We first derive matched-filter quantized VB (MF-QVB) and linear minimum mean-squared error quantized VB (LMMSE-QVB) detection methods assuming the channel state information (CSI) is available. Then we extend these methods to the joint channel estimation and data detection (JED) problem and propose two methods we refer to as MF-QVB-JED and LMMSE-QVB-JED. Unlike conventional VB-based detection methods that assume knowledge of the second-order statistics of the additive noise, we propose to float the noise variance/covariance matrix as an unknown random variable that is used to account for both the noise and the residual inter-user interference. We also present practical aspects of the QVB framework to improve its implementation stability. Finally, we show via numerical results that the proposed VB-based methods provide robust performance and also significantly outperform existing methods., 14 pages, 7 figures, submitted for journal publication

Compressible mixing layer instabilities are of importance to a wide range of environmental and industrial applications. Past studies have focused on either ideal-gas or real-fluid thermodynamic regimes of single-species mixing layers. However, mixing layers of binary mixtures at supercritical conditions, commonly encountered in fuel injection systems, introduce additional complexities due to the added compositional degree-of-freedom. Moreover, the effect of strong variations in thermodynamic response functions across the Widom line on the binary mixing layer stability remains poorly understood. Thus, the objective of this study is to examine the coupling between the hydrodynamic instability and the real-fluid thermodynamics across the Widom line and its effects on the overall binary mixing layer dynamics. To this end, we develop a linear stability analysis of the full binary-species compressible transport equations coupled with the PC-SAFT equation of state. Analysis shows the existence of a novel instability mechanism that arises from juxtapositioning of the Widom-line transition and the hydrodynamic inflection point. This novel thermodynamically induced instability mechanism has the net effect of destabilizing the binary mixing layer at lowering supercritical conditions towards the critical pressure point. This is in contrast to previous stability analyses of supercritical single-species mixing layers, where increasing pressure destabilizes the flow due to its effect on reducing the density stratification. The discovered thermodynamically induced instability mechanism of binary mixing flows highlights the need for an extension of classical instability criteria to incorporate the effect of strong variations in the thermodynamic response functions across the Widom line on mixing layer instability.

In this study, Bi0.5(Na1–xKx)0.5SnO3 (BNKS) ceramics (x = 0, 0.1, 0.2, 0.3, and 0.4) were fabricated via ultrasound wave before milling. The time of ball milling decreased from 20 to 1 h. The X-ray diffraction patterns show that the BNKS has a single-phase structure. When the potassium content increases, the phase structure of the ceramics changes from rhombohedral to tetragonal. When sintered at 1100 °C and x = 0.2, the ceramics’ physical properties are the best with the mass density of 5.59 g/cm3, the electromechanical coupling constants kp of 0,31 and kt of 0.27, the remanent polarization of 11.9 µC/cm; the dielectric constant εr of 1131, and the highest dielectric constant emax of 4800.

The optimal training of the highly specialized congenital heart surgeon is a long and complex process, which is a significant challenge in most parts of the world. The World Society for Pediatric and Congenital Heart Surgery (WSPCHS) has established the Global Council on Education for Congenital Heart Surgery as a nonprofit organization with the goal of assessing current training and certification and ultimately establishing standardized criteria for the training, evaluation, and certification of congenital heart surgeons around the world. The Global Council and the WSPCHS have reviewed the present status of training and certification for congenital cardiac surgery around the world. There is currently lack of consensus and standardized criteria for training in congenital heart surgery, with significant disparity between continents and countries. This represents significant obstacles to international job mobility of competent congenital heart surgeons and to the efforts to improve the quality of care for patients with Congenital Heart Disease worldwide. The purpose of this article is to summarize and document the present state of training and certification in congenital heart surgery around the world.

The purpose of this paper is to approximate a given map by the pertinent Euler-Lagrange-Jensen generalized quintic functional map, and by the Euler-Lagrange-Jensen alternative generalized quintic functional map. The obtained results are extensions of certain stability results from Banach spaces to quasi-Banach spaces. The obtained results are supported by the examples.

Objectives: This study evaluates the results of applying primary sutureless technique in surgical repair of total anomalous pulmonary venous connection at Children Heart Center, Vietnam National Children's Hospital. Methods: A retrospective study was conducted to evaluate the short-term outcomes of primary sutureless repair for all patients diagnosed with obstructed total anomalous venous connection (TAPVC) from July 2015 to December 2016. Results: There were 25 patients undergoing primary sutureless repair during the study period. The mean age and the mean weight are 77.00 ± 23.26 days and 3.93 ± 1.16 kg, respectively. There were 19/25 (76%) cases with preoperative respiratory failure with 14 cases (56%) requiring mechanical ventilation before surgery, of which 9 patients (36%) had life-threatening acute pulmonary edema from before emergency surgical repair. There were 17 cases admitted to the hospital with cardiogenic shock. Evaluation of transthoracic echocardiography showed 15 cases of supracardiac TAPVC, 5 cases of infracardiac TAPVC, 2 cases of intracardiac, 2 cases of mixed, and 1 case of partial TAPVC. The mean aortic cross-clamp time was 65.40 ± 23.34 minutes, the average cardiopulmonary bypass time was 119.72 ± 34.85 minutes, the mean surgery time was 200.04 ± 39.42 minutes. 9 cases underwent circulatory arrest and 7 cases underwent low-flow bypass during surgery. 3 patients died in the postoperative period, of which 2 from septic shock and multi-organ failure, 1 patient from respiratory failure after extubation due to laryngomalacia. The reoperation rate was 2/25 as a consequence of recurrent pulmonary vein stenosis. Conclusions: The primary sutureless repair for obstructed anomalous pulmonary venous connection is safe and favorable. Long-term outcomes follow-up are essentially required.

Objective: This study focuses on primary outcomes of one-stage repair for interrupted aortic arch (IAA) from a single institution from Vietnam. Methods: Between 2012 and September 2017, 27 patients underwent one-stage repair in Children Heart Center, National Hospital of Pediatrics. Kaplan-Meier survival analysis plotted survival and freedom from reoperation curves from follow-up data. Results: Median age was 53 days (range, 9 days to 5 months) and weight was 3.5 kg (range, 2.3 to 6.5 kg). IAA type A in 16 cases (59.3%), IAA type B in 11 case (40.7%). Associated anomalies were ventricular septal defect in 20 (74.1%), aortopulmonary window in 4 (14.8%), truncus arteriosus in 3 (11.1%). Fourteen patients (51.9%) have left ventricular outflow tract obstruction (LVOTO). Median follow-up was 17 months (range, 1 day to 71 months). Survival rates at 30 days, 1 year and 5 years were 81.5%, 77,6% and 77,6% respectively. There were 5 early deaths in hospital, 4 deaths related to nosocomial infection with positive results in blood culture or endotracheal tube, the other was sudden death. One late death after 4 months was caused by severe pulmonary artery stenosis after total repair of interrupted aortic arch associated with truncus arteriosus. There were 5 late reoperations or balloon angioplasty, reoperation for LVOTO in 3, right ventricular outflow tract reconstruction in 1, the other required balloon angioplasty for recurrence of aortic arch stenosis. Conclusion: Primary outcomes of one-stage repair for interrupted aortic arch are safe in our institution. Long-term outcomes evaluation is needed for this complex congenital heart disease.

Ventilator-associated pneumonia (VAP) has emerged as a critical issue in the intensive care unit (ICU) because of its high burden on patients and medical staff. Here, we examined the potential for reducing VAP incidence through physical oral care interventions without any medication.This prospective interventional study compared VAP incidence during an 8-month baseline period (usual oral care) and a 9-month intervention period (physical oral care with sponge brush) among patients who received mechanical ventilation for48 h in a tertiary care hospital in Vietnam from 2017 to 2019. Physical oral care was provided by general ICU nurses who had been trained by dentists and infection control nurses. VAP was diagnosed using the Clinical Pulmonary Infection Score.In total, 423 patients were enrolled in the baseline group and 454 patients were enrolled in the intervention group; 303 and 300 patients, respectively, were included in the analysis. Two hundred thirty-eight VAP episodes were identified: 135 (44.6%) during the baseline period and 103 (34.3%) during the intervention period. Univariate analysis revealed significant reduction of VAP occurrence in the intervention period (odds ratio = 0.65; 95% confidence interval = 0.47-0.90; P = 0.010). The incidences of VAP per 1000 ventilator-days were 63.4 (135/2128) during the baseline period and 48.4 (103/2128) during the intervention period (P = 0.038).Physical oral care without any medication (e.g., chlorhexidine) reduced VAP incidence in the ICU. This method could be used to reduce VAP incidence, particularly in countries with limited medical resources.

TÓM TẮT Mục tiêu: Phẫu thuật chuyển vị đại động mạch hiện nay đã trở thành phẫu thuật thường quy điều trị cho các bệnh nhân chuyển gốc động mạch. Nghiên cứu này được tiến hành nhằm đánh giá kết quả điều trị của phẫu thuật chuyển vị đại động mạch tại Trung tâm Tim mạch trẻ em-Bệnh viện Nhi Trung ương. Phương pháp: Từ tháng 2 năm 2010 đến tháng 12 năm 2016, tổng số 304 bệnh nhân đã được tiến hành phẫu thuật chuyển vị đại động mạch tại Trung tâm Tim mạch trẻ em-Bệnh viện Nhi Trung ương được thu thập đủ dữ liệu và đưa vào nghiên cứu. Kết quả: Trong nhóm nghiên cứu, tỷ lệ nam/nữ là 225/79 (2.85/1). Có 149 bệnh nhân (49%) chuyển gốc động mạch-vách liên thất nguyên vẹn, 106 bệnh nhân (34.8%) chuyển gốc động mạch-thông liên thất và 49 bệnh nhân (16.2%) thất phải hai đường ra thể chuyển gốc động mạch-bất thường Taussig-Bing. Tuổi phẫu thuật trung bình của nhóm nghiên cứu là 49,94 ± 47,43 (1- 320 ngày tuổi) ngày, cân nặng trung bình của nhóm phẫu thuật là 3,67 ± 0,77 kg (2,1-6.7kg). Có 156 bệnh nhân (51.3%) được phá vách liên nhĩ bằng bóng, 102 bệnh nhân (33.6%) được truyền Prostaglandin E1 trước phẫu thuật, 2 bệnh nhân được huấn luyện thất trái trước phẫu thuật. Trong nhóm nghiên cứu, có 28 bệnh nhân (9.2%) hẹp eo động mạch chủ hoặc thiểu sản quai động mạch chủ, và 3 bệnh nhân (1%) gián đoạn quai động mạch chủ được tiến hành phẫu thuật sửa chữa 1 thì với kỹ thuật tưới máu não chọn lọc. Thời gian cặp động mạch chủ trung bình là 131,43±37,65 phút (56-279 phút), thời gian chạy máy trung bình 191,96±81,17 phút (92-924 phút). Có 4 bệnh nhân cần ECMO hỗ trợ sau phẫu thuật. Có 25 bệnh nhân (8.2%) bệnh nhân tử vong tại bệnh viện, 5 bệnh nhân tử vong muộn sau khi xuất viện (1.6%). Có 7 bệnh nhân (2.3%) cần được phẫu thuật lại trong thời gian theo dõi sau phẫu thuật trên tổng số 225 bệnh nhân theo dõi liên tục sau phẫu thuật (49 bệnh nhân mất liên lạc hoặc không khám lại). Phân tích hồi quy đa biến logistic cho thấy nguy cơ tiên lượng tử vong tại bệnh viện bao gồm các yếu tố sau: tổn thương quai động mạch chủ. [(Odds Ratio: OR) = 7.3); để hở xương ức (OR=5.9); nhiễm trùng phổi (OR= 5.1); nhiễm khuẩn huyết (OR= 30.9); suy gan (OR=33.9); và loạn nhịp sau phẫu thuật (OR=5.6). Yếu tố tiên lượng nguy cơ phẫu thuật lại có liên quan đến tổn thương quai động mạch chủ (OR=29.6). Kết luận: Kết quả phẫu thuật chuyển vị đại động mạch tại Trung tâm Tim mạch trẻ em-Bệnh viện Nhi Trung ương là khả quan và an toàn. Một nghiên cứu với thời gian theo dõi dài hơn và với số lượng bệnh nhân nhiều hơn là hoàn toàn cần thiết. ABSTRACT OUTCOMES OF ARTERIAL SWITCH OPERATION AT NATIONAL CHILDREN’S HOSPITAL, HANOI, VIETNAM Objective: The arterial switch operation (ASO) has now become a routine treatment for patients with transposition of the great arteries (TGA). This study was conducted to evaluate the surgical results of ASO at Children Heart Center, National Children’s Hospital, Hanoi, Vietnam. Methods: From February 2010 to December 2016, a total of 304 patients underwent ASO at Children Heart Center have collected to this study. Results: In the study group, the ratio of male/female was 225/79 (2.85/1). There were 149 patients (49%) TGA-intact ventricular septum, 106 patients (34.8%) TGA-ventricular septal defect, and 49 patients (16.2%) of double outlet of the right ventricle-transposition’s type (Taussig-Bing variant). The mean age of the patients was 49.94 ± 47.43 days (1- 320), the mean weight was 3.67 ± 0.77 kg (2.1-6.7). There were 156 patients (51.3%) performed atrial septostomy, 102 patients (33.6%) were infused with Prostaglandin E1 before surgery, and 2 patients underwent left ventricular training before ASO. In the study group, 28 patients (9.2%) have coarctation of the aorta or aortic arch hypoplasia, 3 patients (1%) have interrupted aortic arch, who underwent 1 stage repair with regional cerebral perfusion. The aortic cross clamp time was 131.43 ± 37.65 minutes (56-279), the bypass time was 191.96 ± 81.17 minutes (92-924). Four patients need ECMO support after surgery. 25 patients (8.2%) died in-hospital, 5 died late after discharge (1.6%). There were 7 patients (2.3%) who required reoperation during follow-up after surgery, in a total of 225 patients monitored continuously after surgery (49 patients lost follow-up or did not re-examine). Multivariate logistic regression analysis showed the prognostic risk factors of hospital mortality including the following factors: aortic arch anomaly (OR = 7.3); open sternum (OR = 5.9); lung infection (OR = 5.1); sepsis (OR = 30.9); liver failure (OR = 33.9); and postoperative arrhythmias (OR = 5.6). The prognostic risk factors for reoperation are aortic arch anomaly (OR = 29.6). Conclusions: Mid-term results of ASO in Children Heart Center-National Children’s Hospital are excellent. Further investigation is necessary.

TÓM TẮT Mục tiêu: Đường mổ dọc theo đường nách giữa bên phải đã được thực hiện cho phẫu thuật tim hở với tính thẩm mĩ cao và hiệu quả tương đương đã dần thay thế cho đường mổ giữa xương ức. Mục đích của nghiên cứu này nhằm đánh giá hiệu quả và mức độ an toàn của đường mổ dọc theo đường nách giữa bên phải cho sửa chữa những bệnh tim bẩm sinh đơn giản ở trẻ em tại Bệnh viện Nhi Trung Ương. Phương pháp: Trong thời gian từ tháng 8 năm 2019 đến tháng 12 năm 2020, các bệnh nhân được tiến hành phẫu thuật tim hở áp dụng đường mổ dọc theo đường nách giữa bên phải tại Bệnh viện Nhi Trung ương được thu thập vào nghiên cứu này. Kết quả: Trong thời gian tiến hành nghiên cứu, có tổng số 99 trường hợp được thu thập vào nghiên cứu. Tuổi phẫu thuật trung bình 52,96 ± 44,97 tháng (5-181), cân nặng trung bình 15,31 ± 8,65 kg (6-54). Có 43 bệnh nhân được tiến hành vá thông liên nhĩ lỗ thứ phát, 40 bệnh nhân vá thông liên thất, 8 bệnh nhân sửa chữa bệnh thông sàn nhĩ thất bán phần, 8 bệnh nhân thông liên nhĩ lỗ xoang tĩnh mạch kèm theo bất thường tĩnh mạch phổi bán phần bên phải, trong đó có 2 bệnh nhân được thực hiện kĩ thuật Warden cải tiến. Thời gian cặp động mạch chủ và chạy máy trung bình của các bệnh nhân trong nhóm nghiên cứu lần lượt là 40,08 ± 22,70 (10-118) phút và 60,65 ± 27,18 (25-172) phút. Không có bệnh nhân tử vong tại viện và không có tử vong muộn. Không có trường hợp nào phải chuyển cách tiếp cận đường mổ khác. 1 bệnh nhân phải mổ lại để mở rộng lỗ PFO và đặt ECMO hỗ trợ do suy tâm trương thất trái sau mổ, 1 bệnh nhân cần đặt máy tạo nhịp vĩnh viễn do block nhĩ thất hoàn toàn sau mổ thông sàn nhĩ thất bán phần. Kết quả theo dõi siêu âm sau mổ không có thông liên nhĩ và thông liên thất tồn lưu, không có trường hợp nào hở trung bình-nặng van 2 lá và van 3 lá. Thời gian theo dõi trung bình là 6,91±3,85 (2-18) tháng. Vết mổ liền tốt, ngực và vú ở trẻ gái không có biến dạng khi khám lại. Kết luận: Kết quả phẫu thuật sử dụng đường mổ dọc nách giữa bên phải tại Bệnh viện Nhi Trung ương có mức độ an toàn và hiệu quả cao cho sửa chữa bệnh tim bẩm sinh đơn giản ở trẻ em, với mức độ chấn thương thấp và tính thẩm mĩ cao. Đây là phương pháp tiếp cận phẫu thuật có thể cân nhắc thay thế cho phẫu thuật đường giữa xương ức với những trường hợp cụ thể và thích hợp. ABSTRACT Mini-invasive open heart surgery for children by the right vertical infra-axillary approach: Short term results at Vietnam National Children’s Hospital Objectives: The right vertical infra-axillary incision has been applied for open‐heart surgery with a higher cosmetic result and comparable outcomes, and was considered as an alternative to standard median sternotomy. This study aimed to evaluate the efficacy and safety of the right vertical infra-axillary incision for the correction of simple congenital heart defects in children at National Hospital of Pediatric. Methods: From August 2019 to December 2020, a consecutive of patients who underwent open heart surgery via the right vertical infra-axillary incision in our center was collected to this study. Results: There were 99 childrens who underwent open heart surgery using the right vertical infra-axillary incision for simple congenital heart defects correction during the study period. The mean age 52,96 ± 44,97 months (5-181) and the mean weight 15,31 ± 8,65 kg (6-54). There were 43 patients undergoing ASD closure, 40 patients underwent VSD closure, 8 patients have partial atrioventricular septal defect, 8 patients have partial anomalous pulmonary venous connection with 2 patients underwent modified Warden procedure. The mean aortic cross clamp time and cardiopulmonary bypass time were 40,08 ± 22,70min (10-118) and 60,65 ± 27,18min (25-172), respectively. There were no hospital deaths and late deaths. There was no patient required conversion to sternotomy approach. 1 patient needed reoperation to enlarge PFO with ECMO support due to heart failure, and successfully withdrawn ECMO after 3 days. 1 patient with complete AV block requires permanent pacemaker placement. Follow-up echocardiography showed no residual ASD or VSD, no moderate-severe tricuspid and mitral regurgitation. All patients are in excellent condition with a mean follow-up of 6,91 ± 3,85 (2-18) months. The incision healed well, and the thorax with the breast showed no deformity at the latest follow-up. Conclusions: The surgical outcomes of open heart surgery using the right vertical infra-axillary incision is safe and high effective for corrective of simple congenital heart defects in children, with lower trauma and higher cosmetic results. This approach provides a good alternative to the standard median sternotomy with individual selected patients.

Background Methamphetamine use could jeopardize the current efforts to address opioid use disorder and HIV infection. Evidence-based behavioral interventions (EBI) are effective in reducing methamphetamine use. However, evidence on optimal combinations of EBI is limited. This protocol presents a type-1 effectiveness-implementation hybrid design to evaluate the effectiveness, cost-effectiveness of adaptive methamphetamine use interventions, and their implementation barriers in Vietnam. Method Design: Participants will be first randomized into two frontline interventions for 12 weeks. They will then be placed or randomized to three adaptive strategies for another 12 weeks. An economic evaluation and an ethnographic evaluation will be conducted alongside the interventions. Participants: We will recruit 600 participants in 20 methadone clinics. Eligibility criteria: (1) age 16+; (2) Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) scores ≥ 10 for methamphetamine use or confirmed methamphetamine use with urine drug screening; (3) willing to provide three pieces of contact information; and (4) having a cell phone. Outcomes: Outcomes are measured at 13, 26, and 49 weeks and throughout the interventions. Primary outcomes include the (1) increase in HIV viral suppression, (2) reduction in HIV risk behaviors, and (3) reduction in methamphetamine use. COVID-19 response: We developed a response plan for interruptions caused by COVID-19 lockdowns to ensure data quality and intervention fidelity. Discussion This study will provide important evidence for scale-up of EBIs for methamphetamine use among methadone patients in limited-resource settings. As the EBIs will be delivered by methadone providers, they can be readily implemented if the trial demonstrates effectiveness and cost-effectiveness. Trial registration ClinicalTrials.gov NCT04706624. Registered on 13 January 2021. https://clinicaltrials.gov/ct2/show/NCT04706624

OBJECTIVES The outcomes of the single-stage surgical repair of aortic arch hypoplasia (AAH) and/or coarctation of the aorta (CoA) associated with ventricular septal defect (VSD) remain controversial, especially in a lower middle-income country. This study reports the results of a single-stage repair protocol at our institution for AAH/CoA with VSD using selective cerebral perfusion. METHODS This retrospective study included 100 consecutive patients who underwent single-stage repair via median sternotomy using selective cerebral perfusion for AAH/CoA with VSD from July 2010 to March 2017. RESULTS The patients consisted of 65 males and 35 females. The median age of the patients was 67 days (range 4–2266 days); the median weight was 3.8 kg (range 2.1–15 kg). The average cardiopulmonary bypass time was 132 ± 28 min, the aortic cross-clamp time was 92 ± 23 min and the selective cerebral perfusion time was 33 ± 10 min. The survival rate of all patients was 94.7 ± 2.3%, with an in-hospital mortality of 5% and no late mortality at a median follow-up of 37 months (range 4–96 months). Four patients required reoperation due to recoarctation. The overall event-free survival rate following surgery was 87.1%. The median pressure gradient across the anastomosis at the last follow-up was 8.3 ± 2.8 mmHg. Multivariate logistic regression analysis revealed proximal aortic arch obstruction as a predictor of mortality (odds ratio = 3.8). The aortic isthmus diameter was identified as a predictor for reintervention by Cox regression (hazard ratio = 6.7). CONCLUSIONS Single-stage repair for AAH/CoA with VSD is safe and feasible in a developing country.

Transgender women are at higher risk of HIV infection, however, there is a lack of information about HIV infection and related factors among transgender women in Vietnam. From February 2018 to June 2018, 456 transgender women were recruited in the study using Respondent-Driven Sampling technique. Participants completed the computer-based questionnaire and were tested for HIV serostatus. Multivariable logistic regression was used to identify factors related to HIV infection. The prevalence of HIV infection was 77 (16.5%), of which 19 (24.7%) were not aware of their HIV-positive status prior to the study. Factors associated with HIV infection included popper use (aOR 2.01, p = 0.044) and having regular male partner(s) (aOR 0.42, p = 0.006). More efforts are needed to reduce the high prevalence of HIV infection, such as expanding the reach of HIV screening and prevention programs to the transgender women population, particularly for substance users. Electronic supplementary material The online version of this article (10.1007/s10461-020-02867-5) contains supplementary material, which is available to authorized users.

Irradiated star apples at the minimum absorbed dose of 400 Gy for phytosanitary purpose in Vietnam have been already approved to import to US. In this study, the fresh star apples were treated with electron beams at doses of 0.4, 0.6, 0.8 and 1.0 kGy to evaluate its effect on quality of fruits. The results showed that electron beam radiation doses of 0.4 kGy and 0.6 kGy did not affect to the surface color and percentage of weight loss of fruits. There was significant difference in overall acceptability score with the values of 3.95, 3.92 and 2.45 between irradiated fruits at 0.4, 0.6 kGy and the control (0 kGy) respectively after 6 days in storage at the ambient conditions (temperature of 26±1oC and humidity of 85-90%). Thus, dose range between 0.4 and 0.6 kGy should be used to extend the shelf life of star apple fruits. Because of the low penetration depth of electron beams onto products, dose uniformity ratio (DUR) in the standard carton box for packaging the star apple fruits as well as absorbed doses outside and inside of fruits were calculated.

Suspended sediment concentration (c) has been considered a critical environmental factor in reef habitats; however, the values and variations of c are not evident in a unique reef mainly created by crustose coralline algal concretions compared to abundant studies in coral reefs. The results of real-time and long-term monitoring of waves and c over the intertidal algal reef are reported because of the construction of an offshore industrial harbor near the reef. The real-time monitoring systems were based on techniques, including optical backscatter sensors (OBSs) for measuring c, pressure sensors for measuring waves, data loggers, and wireless networks for data transmission. The instruments sampled every hour and ran continuously and automatically for years. The OBS measurement was compared and validated with biweekly water sampling. A good correlation between the results of the two methods was observed. Nevertheless, more calibrations of OBSs in different seasons reduced the variance between the two methods over a year-long timescale. The year-long data showed a remarkable seasonal variation in c. The average c was approximately 140 mg/l during the winter season, while it was only approximately 70 mg/l during the summer season. The observed c was higher than that in other coral reef environments; the elevated and highly variable c, ranging from approximately 0 to 500 mg/l, may be one factor that creates the unique algae reef environment. The year-long measurement of waves and c showed that the variation in c was mainly due to the variation in waves in different seasons and was well correlated with the wave-induced bed shear stress. The real-time and long-term data measured by the system will aid in better understanding and providing useful environmental data for accessing future environmental changes and protecting reef habitats.

We develop a theoretical trade model based on classical welfare economics and apply it empirically to both importers and exporters of shrimp, the most traded seafood, to determine the effects of the Covid-19 pandemic on the excess supply and excess demand of shrimp industry. We consider two time periods and compare these to the base period before the pandemic. Period 1 (March���June 2020): there is a net economic loss globally of $194 million due to lockdowns. Period 2 (July 2020���June 2021): there is a net welfare gain globally of $885 million due to increased shrimp demand. Overall, the global net economic gain was $692 million. For the United States alone, shrimp consumers gained $470 million while shrimp producers gained $24 million, which is relatively consistent with the net quasi-consumer gain of $475 million due to the Covid-19 pandemic.

Presentation 24411

The body plan of animals is laid out by an evolutionary-conserved HOX code which is colinearly transcribed after zygotic genome activation (ZGA). Here we report that SMCHD1, a chromatin-modifying enzyme needed for X-inactivation in mammals, is maternally required for timely HOX expression. Using zebrafish and mouse Smchd1 knockout animals, we demonstrate that Smchd1 haplo-insufficiency brings about precocious and ectopic HOX transcription during oogenesis and embryogenesis. Unexpectedly, wild-type offspring born to heterozygous knockout zebrafish smchd1 mothers exhibited patent vertebrate patterning defects. The loss of maternal Smchd1 was accompanied by HOX epi-mutations driven by aberrant DNA methylation. We further show that this regulation is mediated by Lrif1, a direct interacting partner of Smchd1, whose knockout in zebrafish phenocopies that of Smchd1. Rather than being a short-lived maternal effect, HOX mis-regulation is stably inherited through cell divisions and persists in cultured fibroblasts derived from FSHD2 patients haploinsufficient for SMCHD1. We conclude that maternal SMCHD1/LRIF1 sets up an epigenetic state in the HOX loci that can only be reset in the germline. Such an unusual inter-generational inheritance, whereby a phenotype can be one generation removed from its genotype, casts a new light on how unresolved Mendelian diseases may be interpreted.

Presentation 24167

To maintain and improve an amateur athlete’s fitness throughout training and to achieve peak performance in sports events, good nutrition and physical activity (general and training specifically) must be considered as important factors. In our context, the terminology “amateur athletes” represents those who want to practice sports to protect their health from sickness and diseases and improve their ability to join amateur athlete events (e.g., marathons). Unlike professional athletes with personal trainer support, amateur athletes mostly rely on their experience and feeling. Hence, amateur athletes need another way to be supported in monitoring and recommending more efficient execution of their activities. One of the solutions to (self-)coaching amateur athletes is collecting lifelog data (i.e., daily data captured from different sources around a person) to understand how daily nutrition and physical activities can impact their exercise outcomes. Unfortunately, not all factors of the lifelog data can contribute to understanding the mutual impact of nutrition, physical activities, and exercise frequency on improving endurance, stamina, and weight loss. Hence, there is no guarantee that analyzing all data collected from people can produce good insights towards having a good model to predict what the outcome will be. Besides, analyzing a rich and complicated dataset can consume vast resources (e.g., computational complexity, hardware, bandwidth), and this therefore does not suit deployment on IoT or personal devices. To meet this challenge, we propose a new method to (i) discover the optimal lifelog data that significantly reflect the relation between nutrition and physical activities and training performance and (ii) construct an adaptive model that can predict the performance for both large-scale and individual groups. Our suggested method produces positive results with low MAE and MSE metrics when tested on large-scale and individual datasets and also discovers exciting patterns and correlations among data factors.

Mục tiêu: Đánh giá kết quả trung hạn phẫu thuật sửa chữa bệnh thông sàn nhĩ thất toàn bộ và các yếu tố liên quan có ảnh hưởng tới kết quả phẫu thuật tại Trung tâm Tim mạch trẻ em, Bệnh viện Nhi Trung ương. Đối tượng và phương pháp: Chúng tôi tiến hành nghiên cứu hồi cứu đánh giá kết quả trung hạn của các bệnh nhân đã phẫu thuật sửa chữa thông sàn nhĩ thất toàn bộ từ tháng 4/2015 đến tháng 7/2019 tại Trung tâm Tim mạch, Bệnh viện Nhi Trung ương. Kết quả: Có tổng số 51 bệnh nhân nghiên cứu, tuổi trung bình phẫu thuật là 263 ngày (95 - 3478 ngày), cân nặng trung bình phẫu thuật là 5,8kg (3,7 - 23kg). Có sự khác biệt về thời gian chạy máy tim phổi nhân tạo và thời gian cặp động mạch chủ giữa 2 nhóm 1 miếng vá và 2 miếng vá (p

Background: This study was conducted to evaluate the surgical results of the arterial switch operation for Taussig-Bing variants, at a single institution in a lower-middle income country. Methods: Between June 2010 and December 2018, all consecutive patients diagnosed with Taussig-Bing variants who underwent the arterial switch operation and ventricular septal defect closure were included in the study. Results: A total of 72 patients of Taussig-Bing variants who underwent arterial switch operation and ventricular septal defect closure. There were 10 early deaths (13.9%) and 2 late deaths (2.8%). Intraoperative ventricular septal defect enlargement [hazard ratio (HR) 7.23, 95% confidence interval (CI) 3.1294-16.7167; P < 0.001], secondary aortic cross clamping (HR 28.38, 95% CI 4.8427-166.3484; P < 0.001), post-operative pneumonia (HR 5.64, 95% CI 1.2724-24.9917; P = 0.023), and post-operative sepsis (HR 5.28, 95% CI 1.3512-20.6553; p = 0.017) were risk factors for overall mortality by competing risk analysis. Sixty patients (83.3%) required septoparietal trabeculation division/resection during the arterial switch operation in an attempt to avoid right ventricular outflow tract obstruction. The reoperation rate for right ventricular outflow tract obstruction at last follow up was 6% (3 patients). The estimated freedom from reoperation for right ventricular outflow tract obstruction at 1 year, 5 year and 9 year was 98.3%, 91.9% and 91.9 , respectively. Conclusions: The results of arterial switch operation for Taussig-Bing variants were satisfactory in the operative setting of a lower-middle income country, and performing extensive septoparietal trabeculation division might reduce the reintervention rate for right ventricular outflow tract obstruction in these patients.

Objective: Data on the management and outcomes of acute myocarditis treated with extracorporeal membrane oxygenation (ECMO) among low- and middle-income countries are limited. This study aimed to determine the short-term outcomes and also identify factors associated with ECMO use among children with acute myocarditis at a tertiary children's hospital in Vietnam.Methods: A single-center, retrospective observational study was conducted between January 2016 and February 2021. Pediatric patients with acute myocarditis, aged 1 month to 16 years, were included.Results: In total, 54 patients (male, 46%; median age, 7 years) with acute myocarditis were included; 37 of them received ECMO support. Thirty percent (16/54) of the patients died, and 12 of them received ECMO. Laboratory variables that differed between survivors and non-survivors included median left ventricular ejection fraction (LVEF) at 48 h (42 vs. 25%; p = 0.001), platelet count (304 g/L [interquartile range (IQR): 243–271] vs. 219 g/L [IQR: 167–297]; p = 0.014), and protein (60 g/dl [IQR: 54–69] vs. 55 [IQR: 50–58]; p = 0.025). Among patients who received ECMO, compared with the survivors, non-survivors had a low LVEF at 48 h (odds ratio (OR), 0.8; 95% confidence interval (CI): 0.6–0.9; p = 0.006) and high vasoactive-inotropic score (OR, 1.0; 95% CI: 1.0–1.0; p = 0.038) and lactate (OR, 2.8; 95% CI, 1.2–6.1; p = 0.013) at 24 h post-ECMO.Conclusions: The case fatality rate among children with acute myocarditis was 30 and 32% among patients requiring ECMO support. Arrhythmia was an indicator for ECMO in patients with cardiogenic shock.

Đặt vấn đề: Phẫu thuật sửa toàn bộ tứ chứng Fallot đã được tiến hành tại Việt Nam với kết quả ngắn hạn khả quan, tuy nhiên kết quả lâu dài sau phẫu thuật thì vẫn chưa được làm rõ. Nghiên cứu này của chúng tôi được tiến hành nhằm đánh giá kết quả dài hạn sau phẫu thuật sửa toàn bộ tứ chứng Fallot tại Trung tâm Tim mạch - Bệnh viện Nhi Trung ương. Đối tượng - phương pháp: Các bệnh nhân được phẫu thuật sửa toàn bộ tại Trung tâm Tim mạch - Bệnh viện Nhi Trung ương trong thời gian từ tháng 12 năm 2006 đến tháng 12 năm 2020 được thu thập bệnh án và được đưa vào nghiên cứu. Kết quả: Trong thời gian nghiên cứu, có tổng số 532 trường hợp được phẫu thuật sửa toàn bộ tứ chứng Fallot tại Trung tâm Tim mạch - Bệnh viện Nhi Trung ương. Tuổi phẫu thuật trung bình của các bệnh nhân trong nhóm nghiên cứu là 11.7 tháng (8.8 - 17.4). Trong nhóm nghiên cứu có 11 trường hợp tử vong sớm sau phẫu thuật (2.1%) và 2 trường hợp tử vong muộn sau phẫu thuật (0.4%). Tỷ lệ bệnh nhân cần mổ lại trong nhóm nghiên cứu là 2.3% (12 bệnh nhân). Thời gian theo dõi trung bình sau phẫu thuật là 40.4 ± 26.27 tháng. Triệu chứng suy tim trên lâm sàng theo Ross tại thời điểm khám lại cuối cùng cho thấy phần lớn các bệnh nhân không có biểu hiện suy tim trên lâm sàng, chỉ có duy nhất 1 bệnh nhân Ross - III. Kết quả siêu âm kiểm tra tại thời điểm khám lại cuối cùng cho thấy có: 144 bệnh nhân (27%) có hở van ĐMP tự do, 42 bệnh nhân (7.9%) hở phổi mức độ trung bình, có 90 bệnh nhân (16.9%) có tình trạng giãn thất phải sau mổ ở các mức độ, và 2 trường hợp hở van ba lá mức độ trung bình nặng. Kết quả kiểm tra điện tim cho thấy hình ảnh block nhánh phải chiếm tỷ lệ 54.2%; hình ảnh giãn thất phải chiếm tỷ lệ 68.2%, và 2.3% bệnh nhân có hình ảnh block nhĩ thất độ I. Kết luận: Kết quả lâu dài sau phẫu thuật sửa toàn bộ tứ chứng Fallot tại Trung tâm Tim mạch - Bệnh viện Nhi Trung ương là tốt. Theo dõi lâu dài sau phẫu thuật là cần thiết đối với nhóm bệnh tim bẩm sinh phức tạp này nhằm đánh giá nguy cơ tử vong muộn và các yếu tố liên quan tới mổ lại của bệnh nhân. ABSTRACT RESULTS OF TOTAL CORRECTION FOR TETRALOGY OF FALLOT IN CHILDREN HEART CENTER - NATIONAL CHILDREN’S HOSPITAL VIETNAM Objective: Long term results of treatment for total correction of tetralogy of Fallot is unknow in Vietnam. We conduct this study to evaluate the long - term results of surgical treatment for tetralogy of Fallot in Children Heart Center, National Children Hospital, Hanoi, Vietnam. Methods: A retrospective study was conducted to evaluate the long - term outcome after total correction for tetralogy of Fallot in Children Heart Center - National Children Hospital, Hanoi, Vietnam since December 2006 to December 2020. Results: There were 532 patients operated during the study period. The median patient age was 11.7months (8.8 - 17.4). The hospital mortality was 11 patients (2.1%), and the late mortality was 2 patients (0.4%). There were 12 patients required re - operation during follow up, with the median time of follow - up was 40.4 ± 26.27months. According to Ross classification about heart failure, the majority of the patient have no heart failure, and only 1 patient have Ross - III. The echocardiography at the last visit shows: 144 patients (27%) have free pulmonary regurgitation, 42 patients (7.9%) have moderate pulmonary regurgitation, and 90 patients (16.9%) have right ventricle enlargement, with 2 patients have severe tricuspid valve regurgitation. The electrocardiogram shows: right bundle block was 54.2%; right ventricular dilation was 68.2%, and 2.3% of the patient have first degree of atrioventricular block. Conclusion: Long term results of total correction for tetralogy of Fallot in Children Heart Center, National Children Hospital are good. Further investigation is needed to evaluate the late mortality and morbidity in this complex heart disease. Key words: Tetralogy of Fallot, total correction, long term results.

Objectives: To evaluate the outcomes of arterial switch operation (ASO) in a subgroup of patients who had intramural coronary arteries at National Children’s Hospital. Methods: From 2010 to 2016, 304 patients underwent ASO at National Children’s Hospital. In which, eighteen (5.9%) had intramural coronary arteries. These medical records of these patients were collected and retrospectively reviewed. Results: There were 10 male and 8 female in this group of patients. Patients with intramural coronary arteries had transposition of the great arteries (83.3%, n = 15) or Taussig - Bing anomaly (16.7%, n = 3). At the time of surgery, mean age was 69.5 ± 81.5 [11 - 321] days and mean weight was 3.9 ± 1.1 [2.5 - 6.3] kg. Mean bypass time and mean aortic cross - clamped time were 235 ± 90 [168 - 564] minutes and 149 ± 29 [100 - 255] minutes respectively. There were 3 deaths (16.7%): two hospital deaths (at 6 days and 26 days after ASO), one death after discharge (2 months later). One patient lost follow - up. Other 14 patients are in a good health status after discharge and free of re - intervention or reoperation related to the total correction with the mean follow - up time of 68.0 ± 38.5 [2 - 113] months. Conclusions: Intramural coronary arteries remain a rare coronary anatomic variant following ASO. The outcomes of ASO in this subgroup of patients is quite favorable. Long - term follow - up is necessary.

The air quality index (AQI) forecast in big cities is an exciting study area in smart cities and healthcare on the Internet of Things. In recent years, a large number of empirical, academic, and review papers using machine learning (ML) for air quality analysis have been published. However, most of those studies focused on traditional centralized processing on a single machine, and there had been few surveys of federated learning (FL) in this field. This overview aims to fill this gap and provide newcomers with a broader perspective to inform future research on this topic, especially for the multi-model approach. In this survey, we went over the works that previous scholars have conducted in AQI forecast both in traditional ML approaches and FL mechanisms. Our objective is to comprehend previous research on AQI prediction including methods, models, data sources, achievements, challenges, and solutions applied in the past. We also convey a new path of using multi-model FL, which has piqued the computer science community’s interest recently.