I. Overview of perivalvular leakage: Perivalvular leakage PVL is a unique complication after heart valve replacement, with an incidence of 2%-15%, and is the most common cause of reoperation after valve replacement. Foreign data report a higher incidence of perivalvular leakage in mitral valves than in aortic valves (12.6% > 2.3%) and rarely in tricuspid and pulmonary valves. Whether the incidence of perivalvular leakage is higher in bioprosthetic valves than in mechanical valves is still debated. The primary cause of perivalvular leakage is surgical damage to the annulus, resulting in poor healing of the annulus and suture ring. This is followed by suture tearing due to inflammation. Mild PVL has no clinical symptoms, and when regurgitation is more pronounced it manifests as malaise, dizziness, and fever, with a characteristic murmur in the appropriate auscultatory area. There are also some patients who present with hemolytic anemia and functional insufficiency. Patients may have clinical symptoms immediately after the procedure or years after the procedure. Classification of periprosthetic leaks: Mechanical periprosthetic leaks, biological periprosthetic leaks, and stent periprosthetic leaks are classified according to the type of valve: mitral valve PPL (periprostheticleaks) are classified into three types according to the size of the leak (based on the results of intraoperative exploration), namely, small (1-2 mm), medium (3-5 mm), and large (6-15 mm), of which the cases The distribution was 43%; 27% and 30%, respectively. Based on transesophageal echocardiography, mitral PPL was classified into 4 degrees, namely, micro-regurgitation: instantaneous flow <1 ml, with the regurgitant column close to the orifice; mild regurgitation: instantaneous regurgitant flow of 1-5 ml, with the regurgitant column occupying less than 1/3 of the left atrial long axis and width <25 px; moderate regurgitation: instantaneous regurgitant flow of 5-10 ml, with the regurgitant column occupying 1/3 to 1/2 of the left atrial long axis and width 1 to 50 px; and severe regurgitation: instantaneous regurgitant flow of 5-10 ml, with the regurgitant column occupying 1/3 to 1/2 of the left atrial long axis and width 1 to 50 px. ～For aortic PPL, the regurgitant column is considered mild if it reaches the edge of the mitral leaflet, moderate if it reaches between the tendon and papillary muscle, and severe if it reaches below the papillary muscle to the apex. Detection of perivalvular leaks: 1. Ultrasound detection: ① Transthoracic ultrasound (TTE) is a common method for detecting perivalvular leaks. Color Doppler is more sensitive and can clearly show perivalvular high-speed regurgitant signals. Two-dimensional images are less sensitive and can clearly show perivalvular fissures in only some cases. ② Transesophageal ultrasound (TEE) shows the size and location of the leak, and the tiny regurgitant bundle more clearly than transthoracic ultrasound. ③Three-dimensional ultrasound can more clearly identify the relationship between perivalvular leaks and valve leaflets, and the structure of perivalvular leaks and surrounding tissues, which is a guide before and after perivalvular leak sealing. In addition to identifying perivalvular leaks, ultrasound can also evaluate leaflet function, the relationship between the leak and prosthetic valve position, and determine whether there is a combination of thrombus, redundancy, and infective endocarditis. In addition, ultrasound can guide the interventional treatment of perivalvular leaks. Intracardiac ultrasound (ICE) is invasive and has a greater significance in the diagnosis, monitoring, and interventional guidance of perivalvular leaks. 2.Contrast examination: It is the best method to confirm the diagnosis and can guide the choice of treatment. Perivalvular leaks have no tendency to close spontaneously and tend to expand with prosthetic valve activity, especially when the left atrioventricular cavity is significantly enlarged and the annulus is diseased; in addition, perivalvular leaks are easily complicated by prosthetic valve endocarditis, so they should be treated actively. The treatment of perivalvular leaks has traditionally been surgical, with both repair and reoperative prosthetic valve replacement. Surgical reoperation is associated with higher risks and increased mortality. Since 1992, there have been a number of reports of successful PPL closure via femoral artery puncture with the placement of a blocking parachute. The choice of the occluder depends on the location, size and shape of the perivalvular leak and the distance from the leaflet. Contraindications to perivalvular leak occlusion: perivalvular leaks with recent valve replacement; unstable swaying replacement valves; active infective endocarditis; bulky growths around perivalvular leaks; fresh thrombus at the site of infection or operation; and recent arterial system embolism. Devices for blocking perivalvular leaks: There is no specific blocking umbrella for closure of PPL; commonly used are double-sided umbrella, spring ring, atrial defect blocking umbrella, myocardial ventricular defect blocking umbrella, and PDA blocking umbrella. PPL of the aortic valve is often treated by retrograde approach (Retrograde transarterial approach) to the aortic valve via the femoral artery or the radial artery. PPL of the mitral valve is usually performed by puncturing the interatrial septum via the venous route (Antegrade transseptal approach) as the access route. Complications of interventional therapy: mainly prosthetic valve dehiscence, thrombosis, infective endocarditis, prosthetic valve leaflet functional impairment, hemolytic anemia, arterial system embolism and blocker dislodgement embolism, etc. V. Prospects for perivalvular leaks With the increase in surgical valve replacement procedures, the number of patients with perivalvular leaks is also increasing, and interventional therapy provides an excellent treatment option for such patients. With the continuous development of intra-cardiac ultrasound (ICE) and three-dimensional ultrasound technology, better detection methods and more accurate guidance for interventional treatment can be provided for perivalvular leaks. In addition, with the further design and development of special interventional devices and instruments for perivalvular leaks, interventional treatment for perivalvular leaks will flourish, and patients with perivalvular leaks will gain greater benefits from interventional treatment to the greatest extent.