Public condition directory
Browse public condition summaries from China medical resources by stable specialty category.
Sinus arrest
The heart's pacemaker is called the sinoatrial (SA) node. The SA node is controlled by the nervous system and is responsible for initiating electrical impulses that stimulate the heart muscle to contract and pump blood. Sinus arrest, also known as sinus standstill, refers to a temporary cessation of electrical impulse generation by the SA node, leading to a temporary halt in atrial or entire heart activity.
View detailsMultivalvular heart disease
Multivalvular heart disease refers to a condition affecting two or more heart valves simultaneously. Among these, combined mitral and aortic valve disease is clinically more common. It frequently occurs in the elderly, primarily manifesting as various symptoms caused by heart failure, such as dyspnea, easy fatigability, palpitations, and arrhythmias.
View detailsMitral annular calcification
The mitral valve is located between the left atrium and the left ventricle, and its main function is to prevent blood from flowing backward. Mitral annular calcification refers to the deposition of calcium salts around the heart valve, causing the valve to narrow or fail to close properly. Mild cases of this condition are asymptomatic, while severe cases may present with symptoms such as dyspnea, hemoptysis, and coughing.
Mitral stenosis
The mitral valve is located between the left atrium and the left ventricle. Its function is to ensure blood flows from the left atrium into the left ventricle and prevent backflow. Mitral stenosis refers to the narrowing of the mitral valve opening, which obstructs blood flow from the left atrium into the left ventricle. When blood accumulates in the left atrium, it may backflow into the lungs, causing pulmonary hypertension, and in severe cases, lead to heart failure. This condition is relatively common, predominantly affecting young and middle-aged adults between 20 and 40 years old, with a higher incidence in females than males.
View detailsReflex syncope
Reflex syncope, also known as neurally mediated syncope, is primarily caused by an intermittent and inappropriate response of cardiovascular reflexes that control the circulatory system to stimuli under normal conditions. This leads to vasodilation and/or bradycardia, resulting in a decrease in arterial blood pressure and reduced global cerebral perfusion, thereby causing transient loss of consciousness. Typical symptoms include sweating, hot skin, nausea, and pallor.
View detailsJunctional escape beat
Normal heartbeats originate in the sinoatrial node. When the sinoatrial node malfunctions or experiences conduction abnormalities, the origin of the heartbeat becomes abnormal. When the heartbeat originates in the atrioventricular node or bundle of His, located between the atria and ventricles (atrioventricular junctional area), it is called an atrioventricular junctional escape beat. Symptoms may include dizziness, fatigue, syncope, and intermittent palpitations.
View detailsPulmonary valve insufficiency
Pulmonary regurgitation refers to the inability of the pulmonary valve to close properly due to organic or functional damage, leading to blood flowing back from the pulmonary artery into the right ventricle during ventricular diastole, causing hemodynamic disturbances. This condition often co-occurs with other cardiovascular diseases, especially in patients with pulmonary hypertension. Isolated congenital pulmonary regurgitation is rare. In the early stages, this condition often presents with no specific symptoms. As the disease progresses, symptoms of right heart failure may appear, such as bilateral lower extremity edema, abdominal distension, and dyspnea.
View detailsPulmonary regurgitation
The pulmonary valve is a heart valve located between the right ventricle and the pulmonary artery. It acts as a one-way valve, preventing blood from flowing back from the pulmonary artery into the right ventricle. If the pulmonary valve cannot close completely, allowing blood to flow back from the pulmonary artery into the right ventricle, it is called pulmonary regurgitation. It is important to note that physiological pulmonary regurgitation, which causes mild backflow, is very common in healthy individuals and generally does not require any treatment or progress further. The symptoms of this condition are non-specific and difficult to distinguish from the symptoms of the primary disease. Main symptoms include cough, chest pain, palpitations, and susceptibility to respiratory infections. As the disease progresses, symptoms of right heart failure may appear, such as edema, hepatomegaly, and dyspnea.
View detailsPulmonary valve stenosis
The pulmonary valve is located between the right ventricle and the pulmonary artery. When the right ventricle ejects blood into the pulmonary artery, the pulmonary valve opens. After ejection, the pulmonary valve closes to prevent blood regurgitation. This process is crucial for pulmonary circulation and cardiac function. Pulmonary valve stenosis refers to a narrowing of the pulmonary valve, supravalvular, or subvalvular regions, which increases resistance during right ventricular ejection, affecting pulmonary blood circulation and increasing the burden on the right ventricle. Over time, this can lead to a series of problems, including heart failure.
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