A Multicenter, Prospective, Randomized Control Study on the Optimal Intervention Approach for High-risk Type B Aortic Dissection

Aortic dissection is characterized by its sudden onset, rapid progression, and life-threatening nature, with a natural mortality rate of 25% within 24 hours and 50% within 48 hours. As China's socioeconomic development accelerates and the population continues to age, the incidence of aortic dissection has been rising year by year. According to the China Cardiovascular Health and Disease Report 2022, cardiovascular diseases are now the leading cause of death among urban and rural residents in China. It is estimated that 245 million people in China suffer from hypertension, a major risk factor for aortic dissection. The Sino-RAD study on aortic dissection indicates that, compared to Western countries, China exhibits a "high incidence, early onset" trend, which is related to poor hypertension control. The average age of Chinese aortic dissection patients is 51.8 years, about 10 years younger than in Western countries, which significantly affects life expectancy and imposes a heavy economic burden on healthcare.

Type B aortic dissection refers to dissections originating from the left subclavian artery and beyond. Since 1999, when thoracic endovascular aortic repair (TEVAR) was first introduced internationally, there has been a revolutionary shift in the surgical treatment of B-type aortic dissection, transitioning from highly invasive open surgeries to minimally invasive endovascular treatments. This shift has greatly reduced perioperative mortality and complications. China's treatment of Type B aortic dissection has kept pace with international advancements. Data from the National Center for Cardiovascular Diseases Quality Control shows that from 2017 to 2022, the number of TEVAR surgeries in China increased from 13,709 per year to 24,076 per year, a growth of 75.6%. The number of hospitals performing TEVAR surgeries also increased from 627 to 1,050. However, with the increase in cases, clinical challenges have also emerged.

Type B aortic dissection patients exhibit both common and individual characteristics. Currently, for acute Type B dissections, regardless of subtype, most patients undergo proximal endovascular repair during the subacute phase, while a "watch and wait" strategy is adopted for dissections distal to the descending aorta. This single treatment approach carries potential risks, including inappropriate indications, mistimed interventions, and uncertain prognoses.

Our team has already established a database and imaging library with nearly ten thousand cases. Building on the study of acute complex, non-complex, penetrating ulcers, and intramural hematomas, we are delving deeper into acute high-risk subtypes and localized contrast enhancement of the aortic wall for more refined classifications. For patients with different classifications and at various stages of dissection, such as hyperacute, acute, and subacute phases, it is critical to develop individualized treatment strategies. These strategies may include optimal medical treatment, proximal endovascular repair alone, or a combination of proximal repair and distal petticoat techniques.

Therefore, large-scale clinical research is urgently needed to identify the best intervention timing and methods, based on refined classifications, to establish personalized, stratified diagnosis and treatment strategies for different patients.