Prevalence of congenital heart disease among school children in Qinghai Province

Medical Problems of Chronic Hypoxia in Highlanders Living on the Tibetan Plateau

Ri-Li Ge. Medical problems of chronic hypoxia in highlanders living on the tibetan plateau. High Alt Med Biol. 00:00-00, 2024.-Health issues at high altitudes arise due to the lower atmospheric pressure and subsequent reduction in the partial pressure of oxygen in ambient air. While much research has been published on health problems of lowlanders who move to high altitudes, less is known about the medical challenges faced by long-term and permanent high-altitude residents, especially in the Qinghai-Tibetan plateau. In this review, we briefly summarized the chronic hypoxia-related health issues in highlanders, focusing on the specific population of the Qinghai-Tibetan plateau. It deals with important health problems for highlanders, including the main disease categories, from chronic mountain sicknesses and pulmonary hypertension (PH) to kidney, neurocognitive impairments, perinatal problems, and congenital heart defect. However, the most hallmark of disorders is excessive erythrocytosis associated with specific symptoms and signs, and high-altitude heart disease is characterized by excessive PH, right ventricular hypertrophy, and right heart failure. We also provide information on potential treatment strategies, including some traditional Tibetan medical practices and also a combination of Western medicine and traditional Chinese medicine to prevent and treat these conditions effectively. This mini-review is heavily based on a couple of decades of research carried out by Chinese high-altitude medical research groups at the Qinghai-Tibetan Plateau. We believe that this review will provide valuable perspective to researchers whose study interest and base lie in high altitude.

Elevated Perspectives: Unraveling Cardiovascular Dynamics in High-Altitude Realms

High-altitude regions pose distinctive challenges for cardiovascular health because of decreased oxygen levels, reduced barometric pressure, and colder temperatures. Approximately 82 million people live above 2400 meters, while over 100 million people visit these heights annually. Individuals ascending rapidly or those with pre-existing cardiovascular conditions are particularly vulnerable to altitude-related illnesses, including Acute Mountain Sickness (AMS) and Chronic Mountain Sickness (CMS). The cardiovascular system struggles to adapt to hypoxic stress, which can lead to arrhythmias, systemic hypertension, and right ventricular failure. Pathophysiologically, high-altitude exposure triggers immediate increases in cardiac output and heart rate, often due to enhanced sympathetic activity. Over time, acclimatisation involves complex changes, such as reduced stroke volume and increased blood volume. The pulmonary vasculature also undergoes significant alterations, including hypoxic pulmonary vasoconstriction and vascular remodelling, contributing to conditions, like pulmonary hypertension and high-altitude pulmonary edema. Genetic adaptations in populations living at high altitudes, such as gene variations linked to hypoxia response, further influence these physiological processes. Regarding cardiovascular disease risk, stable coronary artery disease patients generally do not face significant adverse outcomes at altitudes up to 3500 meters. However, those with unstable angina or recent cardiac interventions should avoid high-altitude exposure to prevent exacerbation. Remarkably, high-altitude living correlates with reduced cardiovascular mortality rates, possibly due to improved air quality and hypoxia-induced adaptations. Additionally, there is a higher incidence of congenital heart disease among children born at high altitudes, highlighting the profound impact of hypoxia on heart development. Understanding these dynamics is crucial for managing risks and improving health outcomes in high-altitude environments.

Epidemiology of Congenital Heart Defects in Perinatal Infants in Guangxi, China

Purpose

To explore the changing trends in the prevalence and epidemiological characteristics of congenital heart defects (CHDs) in perinatal infants (PIs) in Guangxi, China.

Patients and Methods

During 2016 and 2020, the Guangxi Birth Defects Monitoring Network (GXBDMN) monitored a total of 3627108 PIs in this study. The CHDs data for PIs can be obtained from the GXBDMN. The study analyzed the changing trends of total CHDs prevalence and each subtype of CHDs prevalence per year using prevalence-rate ratios (PRR). The correlation between characteristics (such as year, infant gender, maternal age, and quarter) and the prevalence of CHDs was also examined by the PRR.

Results

Between 2016 and 2020, 10817 PIs were diagnosed with CHDs, resulting in an overall CHDs prevalence of 29.82 [95% confidence intervals (CI): 29.26-30.38] per 10000 PIs. CHDs accounted for 24.50% of all types of BDs, making them the most common type of BDs. Atrial septal defect / patent foramen ovale (ASD/PFO), patent ductus arteriosus (PDA), ventricular septal defect (VSD), atrioventricular septal defect (AVSD), persistent left superior vena cava (PLSVC), and tetralogy of Fallot (TOF) were the 6 most common subtypes of CHDs. Together they accounted for 86.24% of all CHDs cases, with a total prevalence of 25.72 (95% CI: 25.20-26.24) per 10000 PIs. The study period saw a significant increase in the prevalence of CHDs (PRR = 1.300, 95% CI: 1.283-1.318), and the maternal age also played a significant role in this increase (PRR = 2.738, 95% CI: 2.428-3.087).

Conclusion

The prevalence of CHDs in Guangxi is rising and has an upward trend with maternal age. ASD/PFO, PDA, VSD, AVSD, PLSVC, and TOF were the top six subtypes of CHDs.

Congenital heart disease: types, pathophysiology, diagnosis, and treatment options

Congenital heart disease (CHD) is a structural abnormality of the heart and/or great vessels and patients with CHD are at an increased risks of various morbidities throughout their lives and reduced long-term survival. Eventually, CHD may result in various complications including heart failure, arrhythmias, stroke, pneumonia, and sudden death. Unfortunately, the exact etiology and pathophysiology of some CHD remain unclear. Although the quality of life and prognosis of patients with CHD have significantly improved following technological advancement, the influence of CHD is lifelong, especially in patients with complicated CHD. Thus, the management of CHD remains a challenge due to its high prevalence. Finally, there are some disagreements on CHD among international guidelines. In this review, we provide an update of the pathophysiology, diagnosis, and treatment in most common type of CHD, including patent foramen ovale, atrial septal defect, ventricular septal defect, atrioventricular septal defect, patent ductus arteriosus, coarctation of the aorta, transposition of the great arteries, congenitally corrected transposition of the great arteries, coronary anomalies, left and right ventricular outflow tract obstruction, tetralogy of Fallot and Ebstein anomaly. In particular, we focus on what is known and what is unknown in these areas, aiming to improve the current understanding of various types of CHD.

Epidemiological Survey of Congenital Heart Disease Among Children Aged from 2 to 18 in Suo County, Nagqu, Tibet

Lin, Tian, Huaping Jia, Yunming Li, Yongxing Xu, Bei Zhao, Dong Zheng, Hongfeng Yan, Meihui Zhao, Yanlei Li, Liping Xia, Fengxia Zhou, Cuiping Liu, Ke Ma, Ma Mi, and Jianwen Gu. Epidemiological survey of congenital heart disease among children aged from 2 to 18 in Suo County, Nagqu, Tibet. High Alt Med Biol. 00:000-000, 2024. Background: Studies have reported the prevalence of congenital heart disease (CHD) in parts of Tibet, but relative epidemiological surveys are rare. We aimed to explore the prevalence of CHD in children and its relationship with family history in Suo County, Nagqu, Tibet, an altitude of 3,980 meters. Methods: We recruited 4,002 children aged 2-18 years. Subjects underwent a family history investigation, cardiac auscultation, and clinical manifestation examination and then received echocardiographic screening. Results: The prevalence of CHD among children in Suo County was 0.97% (39 cases), much higher than the prevalence at sea level. The most common subtype was atrial septal defect, accounting for 53.9% of CHD, followed by patent ductus arteriosus (33.3%) and ventricular septal defect (12.8%). We also found that children whose mothers had previously borne children with CHD had a higher risk of CHD than those without (p = 0.002); other factors related to CHD during pregnancy, such as smoking, drinking, drug use, and viral infection, showed no statistical differences between children with and without CHD. Conclusions: The prevalence of CHD in children in Suo County is much higher than at low altitude, consisting mostly of simple forms with left-to-right shunt, with rare complex CHD. These results support implementing diagnostic and treatment plans to prevent CHD in Suo County.

[Closure of patent ductus arteriosus with OcclutechTM device, experience in an andean country]

Background and Objective

To communicate the experience in an Andean country with the OcclutechTM Duct Occluder device for the closure of patent ductus arteriosus.

Method

observational, retrospective, cross-sectional study with basic statistical analysis. Period: December/2014 to December/2022. Data: medical chart, reports of catheterization.

Results

Forty-six patients, female 71.3%, male 28.7%; age: 0.6-38 years-old (median [Me]: 5.2); weight: 6.3-60 kg (Me: 16.5). Origin: Andean 91.3%, coast 8.7%. Types of patent ductus arteriosus: E 54.4%, A 32.6%, D 13%. Minimum ductal diameter: 1.8-11.8 mm (Me: 3.5). Mean pulmonary artery pressure prior to occlusion: 14-67 mmHg (Me: 27). Pulmonary vascular resistance index prior to occlusion: 0.28-4.9 WU/m2 (Me: 1.3). Six of them were classified as hypertensive patent ductus arteriosus. Occlusion rate: 47.8% immediate, 81% at 24 hours, 100% after six months. Fluoroscopy time: 2-13.8 minutes (Me: 4). Complications: a migrated device. Follow-up: 1-6.5 years.

Conclusions

OcclutechTM Duct Occluder device was effective and safe for the closure of patent ductus arteriosus type E, A and D in low-altitude and high-altitude dwellers, whether they were children or adults, even when these ductus arteriosus were hypertensive.