Background
The aorta is the largest blood vessel in the body. It begins in the heart and provides oxygen to all parts of the body. Aortic dissection occurs when there is a tear in the inner wall of the aorta and bleeding occurs between the inner and outer walls of the blood vessel. It is a severe and often lethal complication. High blood pressure (hypertension) may be a key cause. Other risk factors may include connective tissue disorders, congenital vascular disease (abnormalities present at birth), aortitis (inflammation of the aortic wall), trauma or iatrogenic causes (problems resulting from medical treatment). Chronic type B aortic dissections are typically managed with medical therapy to reduce the stress on the aorta. Current practice guidelines suggest the use of beta-blockers as a first-line treatment.
Study characteristics
We searched scientific databases for randomized controlled trials (studies where people are randomly allocated to treated groups) comparing beta-blockers versus other drugs used in the treatment of hypertension. The studies had to include people with thoracic aortic dissection of any cause that had not been treated with surgery. The evidence is current to January 2014.
Key results
We found no randomized controlled trials.
Quality of the evidence
As of January 2014, there is no evidence to show that beta-blockers are superior to other antihypertensive medications as a first-line treatment. Randomized control trials are needed to determine the best treatment of chronic type B aortic dissections.
We did not find any RCTs that compared first-line beta-blockers with other first-line antihypertensive medications for the treatment of chronic type B TAD. Therefore, there is no RCT evidence to support the current guidelines recommending the use of beta-blockers. RCTs are required to assess the benefits and harms of beta-blockers and other antihypertensive medications as first-line treatment of chronic type B TAD.
Thoracic aortic dissection (TAD) is a severe and often lethal complication in people with hypertension. Current practice in the treatment of chronic type B aortic dissections is the use of beta-blockers as first-line therapy to decrease aortic wall stress. Other antihypertensive medications, such as calcium channel blockers (CCBs), angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs), have been suggested for the medical therapy of type B TAD.
To assess the effects of first-line beta-blockers compared with other first-line antihypertensive drug classes for treating chronic type B TAD.
We searched the Database of Abstracts of Reviews of Effects (DARE) for related reviews. We searched the Hypertension Group Specialised Register (1946 to 26 January 2014), the Cochrane Central Register of Controlled Trials (2014, Issue 1), MEDLINE (1946 to 24 January 2014), MEDLINE In-Process, EMBASE (1974 to 24 January 2014) and ClinicalTrials.gov (to 26 January 2014).
We considered randomized controlled trials (RCTs) comparing different antihypertensive medications in the treatment of chronic type B TAD to be eligible for inclusion. Total mortality rate was the primary outcome of this review. Secondary outcomes included total non-fatal adverse events relating to TADs and number of people not requiring surgical treatment.
Two review authors (KC, PL) independently reviewed titles and abstracts and decided on studies to include based on the inclusion criteria. We resolved discrepancies between the two review authors by discussion.
After a thorough review of the search results, we identified no studies that met the inclusion criteria.