跨导管大动脉置换后心脏导电的变化背后的机制

IntroductionAortic regurgitation is characterized by the backward flow of blood from the aorta into the left ventricle during diastole and arises from the improper closure of the aortic valve. This condition results in left ventricular volume overload and can stem from both acute and chronic etiologies, each contributing uniquely to the disease's progression and symptomatology.Acute and Chronic CausesAcute aortic regurgitation often results from events that suddenly impair the integrity of the...

Aortic regurgitation (AR) is when the aortic valve does not close or seal properly, leading to backward blood circulation from the aorta into the left ventricle during diastole. Common causes of AR include rheumatic heart disease, congenital valve defects, and aortic root dilation. Managing AR requires a multifaceted approach to alleviate symptoms, preserve left ventricular function, and address the underlying cause of the regurgitation. Patients with symptomatic AR or significant left...

Arrhythmias are irregular heart rhythms occurring when the heart's electrical impulses become abnormal. These disturbances can lead to various symptoms, depending on their severity and the underlying cause. Some common factors contributing to arrhythmias include hypoxia, ischemia, electrolyte imbalances, excessive catecholamine exposure, drug toxicity, and muscle overstretching. Arrhythmias can be classified into two main types based on the rate and site of origin of abnormal heart rhythms.

Aortic valve regurgitation (AR) occurs when the aortic valve fails to close properly, allowing blood to flow backward from the aorta into the left ventricle. This backflow can result in two distinct clinical presentations: acute and chronic AR, each characterized by its own set of symptoms and physical findings.Acute Aortic RegurgitationAcute AR presents with a sudden onset of severe symptoms. Patients typically experience profound dyspnea (shortness of breath), chest pain, and signs of left...

IntroductionThe mitral valve, one of the heart's four valves, regulates blood flow. These valves have flaps that open and close to direct blood properly through the heart and body. During each heartbeat, the flaps open for blood to pass through and seal shut to prevent backflow. Specifically, the mitral valve opens to allow blood flow from the heart's upper left chamber to the lower left chamber. It then closes securely as the lower left chamber contracts to pump blood to the body, preventing...

Autorhythmicity is a term that refers to the heart's inherent ability to generate electrical signals and instigate muscle contractions. This self-regulating conduction system within the heart consists of two key components: the pacemaker cells and specialized conducting cells.
The pacemaker cells are located in two primary nodes: the sinoatrial (SA) node and the atrioventricular (AV) node. The SA node pacemaker cells can autonomously depolarize, triggering an action potential that leads to the...