What is the pulmonary artery? The pulmonary artery is also known as the pulmonary artery trunk. In air-breathing vertebrates, it is the artery that directs venous blood from the heart to the lungs. The pulmonary artery emanates from the right ventricle.
What is pulmonary hypertension? Pulmonary hypertension is defined as a mean pulmonary artery pressure >3.33kPa (25mmHg) at rest or >4kPa (30mmHg) during exercise. Since pulmonary vascular resistance is the ratio of the difference between mean pulmonary artery pressure and mean pulmonary venous pressure and pulmonary blood flow, i.e., mean pulmonary artery pressure is the sum of mean pulmonary venous pressure plus the product of pulmonary vascular resistance and pulmonary blood flow, all factors that cause an increase in pulmonary venous pressure, pulmonary blood flow and pulmonary vascular resistance can cause pulmonary hypertension. Pulmonary hypertension is divided into two categories: primary and secondary. Liu Chao, Cardiovascular Surgery Department, First Affiliated Hospital of Zhengzhou University
What congenital heart diseases are likely to be combined with pulmonary hypertension? Common congenital heart diseases that cause secondary pulmonary hypertension include: ventricular septal defect, main pulmonary artery window, atrial septal defect, patent ductus arteriosus, single ventricle, permanent arterial trunk, right ventricular double outlet, and complete atrial septal defect.
What are the symptoms of pulmonary hypertension? Symptoms of pulmonary hypertension include shortness of breath, easy fatigue, syncope, chest pain, and edema in the legs and ankles. In addition, cardiac auscultation may reveal hyper-P2. If not treated, the patient’s pulmonary hypertension can gradually worsen and even shorten life expectancy. Most of the symptoms associated with pulmonary hypertension stem from the failure of the right heart system. Because the right heart is the one that ejects blood into the lungs, if the pulmonary artery pressure increases gradually, the right ventricle becomes increasingly loaded and the symptoms described above occur.
Can pulmonary hypertension be treated? If pulmonary hypertension is caused by a congenital intracardiac defect, early surgical repair of the defect is an important means of completely correcting pulmonary hypertension. However, pulmonary hypertension can occur at all stages of the evolution of congenital heart disease, and the degree of pulmonary vascular disease is an important determinant of the clinical course and feasibility of surgical treatment. Severe pulmonary vascular disease in advanced stages is irreversible and can progress and become life-threatening even after surgical corrective surgery. Therefore, actively seeking effective ways to slow or improve the reconstruction of pulmonary vascular structures and the development of pulmonary hypertension due to high pulmonary blood flow is very important for the success of surgery and the improvement of its prognosis in patients with congenital heart disease.
What are the medical treatments for pulmonary hypertension?
1. Appropriate adjustment of daily physical activities. The intensity of physical activity of patients should be appropriate without symptoms (such as dyspnea, syncope and chest pain), and activities should be avoided after meals, in high and low temperatures.
2. Avoid going to hypoxic environment. Hypoxia can aggravate pulmonary vasoconstriction in patients with pulmonary hypertension. 1500 meters to 2000 meters above sea level is a mild low-pressure hypoxic area, therefore, patients should be advised to avoid such areas. The environment on commercial airplanes is similar to the state of 1500 meters to 2500 meters above sea level, and patients are advised to inhale oxygen while riding.
3. Prevention of infection. Patients with pulmonary hypertension are prone to lung infections and poorly tolerated. Pneumonia accounts for 7% of the total causes of death, and therefore should be diagnosed and treated early and aggressively. Influenza and pneumococcal vaccines are recommended. Patients who are given continuous prostacyclin by intravenous catheter should be alerted to infection by the catheter route if they develop persistent fever.
4. Women of childbearing age should use appropriate methods of contraception. Usually pregnancy and childbirth can worsen the condition of patients and lead to death, with the death rate of patients with severe pulmonary vascular disease being as high as 30% to 50%.
5.Hemoglobin level. Patients with pulmonary hypertension are poorly tolerant of reduced hemoglobin levels, and even mild anemia should be treated promptly. On the other hand, patients with prolonged hypoxemia (e.g., the presence of right-to-left shunt) often develop erythrocytosis and an elevated erythrocyte ratio. When patients have symptoms such as headache and inattention, accompanied by an erythrocyte ratio of more than 65%, bloodletting therapy can be considered to reduce blood viscosity and increase the ability of blood to release oxygen to tissues.
6.Psychotherapy. Patients with pulmonary hypertension have an early age of onset (median age of 40 years) and disrupt their previous lifestyle due to limited physical activity. Moreover, they are often influenced by incorrect information about the disease from lay people, so many patients have varying degrees of anxiety and/or depression. Therefore, patients should be provided with adequate information, actively treated in cooperation with their families and, if necessary, advised to receive treatment from a psychiatrist.
7.Medication includes oral synthetic prostacyclin and its analogues, type 5 phosphodiesterase inhibitors (Viagra), anticoagulants, diuretics, oxygen, digitalis, dopamine, calcium channel blockers, endothelin-1 receptor antagonists, combination therapy, etc.
8. Combined cardiopulmonary transplantation, atrial septal stoma.