Predicting the Risk of Thoracic Aortic Aneurysms and Dissection in Marfan Syndrome and the General Population

Abstract

Thoracic aortic dissection is a devastating event associated with high mortality and morbidity. Prevention via prophylactic aortic surgery in individuals deemed at high risk of dissection remains the primary management strategy. Prior studies describing the risk of dissection have been limited by small sample sizes and inclusion of heterogenous cohorts of patients with different underlying disease entities. Furthermore, most data describes older patient groups and there is a paucity of data for younger patients, such as those with Marfan syndrome. This thesis examines the risk of dissection for individuals in the general population, compared to those with thoracic aortic disease and individuals with Marfan syndrome. A “big data” approach is employed, through pooling available data to generate large sample sizes. Chapter 1 provides an introduction with an overview of the definition, epidemiology, known risk factors and current guideline recommendations regarding thoracic aortic dissection. Chapter 2 describes the incidence of dissection in the general population with large population studies and national registries, specifically focusing on the risk associated with age and sex. Chapter 3 focuses on patients with known thoracic aortic disease and examines the role of aortic diameter as a predictor of dissection in individuals with and without known thoracic aortic disease. Chapter 4 utilises individual patient data and grouped study data to examine the risk factors of thoracic aortic dissection in patients with Marfan syndrome. It also provides estimated event rates for patients based on age, sex and aortic diameter. Chapter 5 discusses the implications of the present findings, recommendations for surgery and directions for future research. The present thesis provides information about the risk of dissection, which will help guide decision-making for clinicians and patients about the appropriate timing of elective aortic surgery to prevent thoracic aortic dissection.