New clinical practice guidelines have been published today, and are intended to act as “guard rails” to determine the treatment options and best practices for managing patients with type B aortic dissection. An important update in the document is the potential for earlier endovascular treatment in patients with uncomplicated type B aortic dissection at higher risk of progressive disease.
The guidelines, produced jointly by the Society of Thoracic Surgeons (STS) and the American Association for Thoracic Surgery (AATS) are published online today in The Annals of Thoracic Surgery and The Journal of Thoracic and Cardiovascular Surgery. The new document offers evidence-based recommendations that include employing a “stepwise approach” to the evaluation and treatment of patients with uncomplicated type B aortic dissection, followed by close clinical surveillance.
“There has been an explosion of information in the form of research reports of varying quality regarding the treatment of type B dissection over the past decade,” said author G Chad Hughes from Duke University Medical Center (Durham, USA). “This guideline is unique in providing surgeons with a comprehensive, up-to-date summary of the state of the evidence, while also serving as ‘guard rails’ that outline treatment options and best practices in certain scenarios. This is a first for any document in the field of type B dissection management.”
A dissection of the aorta occurs when a tear develops within its wall. Type B describes the location of the tear, originating in the descending part of the aorta in the chest and potentially extending into the abdomen.
According to the guideline, aggressive medical therapy is the first step and considered the gold standard for managing patients with uncomplicated type B dissection, while open surgery should be reserved for complicated cases.
Importantly, the guidelines recognise advances in less invasive treatment options for the disease, including the new role of earlier endovascular treatment such as thoracic endovascular aortic repair (TEVAR) in patients with uncomplicated type B aortic dissection. In the early phase of treatment, surgery previously was reserved for patients who had complicated type B dissection; in later phases, for patients who had progression of their disease. Now, the guidelines suggest that surgeons may be able to identify subsets of patients with uncomplicated type B dissection who have a higher risk of progressive disease and treat them earlier with TEVAR—before progression develops. However, this recommendation remains secondary to medical management, and patient selection still needs to be better defined in the future.
For complicated type B dissection patients, TEVAR or open surgery, depending on the anatomy, should be the first-line treatment, according to the guideline. The collective data demonstrated improved outcomes with TEVAR for these patients compared to open surgery or medical therapy alone.
The guideline also states that for some type B dissection patients—such as those with connective tissue disorders or chronic dissections—whose disease has progressed despite medical therapy, a “more durable” open surgical repair may be recommended over TEVAR.
“We expect this guideline to improve the quality of care of patients with type B aortic dissection by providing surgeons the most up-to-date summary of when and how to effectively use which therapies, whether open surgery, endovascular therapy, or a combination of the two over the lifetime of the patient,” said Dawn S Hui (The University of Texas Health Science Center at San Antonio, San Antonio, USA).
“In contrast to individual studies, clinical practice guidelines are unique because they are a high-quality summary and synthesis of what is already known about this topic,” added Hui. “Guidelines are written according to a scientifically rigorous process. Thus, they can help resolve conflicting findings of different studies or define what treatment options are best for specific circumstances.”