Report of four pediatric cases with primary pulmonary hypertension: This disease has not yet been clearly associated with diffuse pulmonary vascular obstructive sexually transmitted diseases, hair abnormalities, pulmonary hypertension, or right ventricular involvement, which are rare clinical features of this disease. In the past, domestic case reports in adults have gradually increased; our hospital has recently treated four cases, indicating that this disease is not uncommon in pediatrics. The disease can occur from newborns to 80-year-olds, and it may affect children and young adults. The incidence in young adult women is higher, but there is no significant gender difference in the incidence among children. The disease exhibits a sporadic distribution, with some cases showing a familial tendency (e.g., family history). Although this disease sometimes shows spontaneous relief, the prognosis is generally poor, as the majority of cases are progressive. The younger the patient, the faster the progression of the disease.
Based on the literature and cases observed at our hospital, the clinical features of Bong disease are as follows: (1) Dyspnea on exertion, syncope, chest pain, hemoptysis, and other symptoms are common. Cyanosis and right heart failure appear later. (2) Pulmonary arteries and crisp valve areas exhibit a split second heart sound, hyperthyroidism, and a jet sound, with no noise or mild systolic murmurs. Severe pulmonary valve and/or tricuspid regurgitation may be present. (3) ECG reveals right axis deviation and right ventricular hypertrophy. (4) X-rays show enlargement of the right ventricle and right atrium, expansion of the pulmonary artery and its branches, and slender peripheral pulmonary vessels. (5) Ultrasound shows increased diameters of the right atrium and ventricle, along with pulmonary artery dilation.
There are no specific diagnostic methods based solely on symptoms, signs, x-rays, and ECG findings. Therefore, Bong disease has a high misdiagnosis rate. Clinical diagnosis of PPH is a diagnosis of exclusion. First, it must be confirmed that pulmonary hypertension indeed exists, and then congenital heart disease, left atrial disease, mitral valve disease, and pulmonary disease leading to pulmonary hypertension must be excluded. It is necessary to carefully inquire about the history and be familiar with the signs of pulmonary hypertension, ECG, and x-ray changes. Right heart catheterization and pulmonary angiography are the main diagnostic tools, but they carry risks, especially in advanced cases. Echocardiography detects a shallow crossing or disappearance of the pulmonary valve curve and notch signs of the CD segment for qualitative diagnosis of pulmonary hypertension. Two-dimensional echocardiography and acoustic contrast observations help exclude cardiovascular diseases that could lead to renewed pulmonary hypertension. In recent years, Doppler spectrum analysis has been used more frequently to estimate pulmonary artery pressure due to its non-invasive, safe, easy, and repeatable nature, making it advantageous for dynamic observation. Two cases underwent catheterization, confirming the diagnosis of PPH. Three cases at our hospital were diagnosed with PPH via ultrasound, reaching the same conclusion. For instance, refractory heart failure precluded catheterization, but pathological examination confirmed plexiform lesions as representative of high-pressure pulmonary vascular changes: (1) thickening of the muscular-type pulse middle layer; (2) muscularization of small arteries; (3) association vein intima ignorance of wall middle thickening and small artery muscle. Our hospital found significant hypertrophy in the middle layer of pulmonary arterioles in infants, consistent with the literature.