Skip Navigation U.S. Department of Health and Human Services
Agency for Healthcare Research Quality
Archive print banner

Clinical Decisonmaking

This information is for reference purposes only. It was current when produced and may now be outdated. Archive material is no longer maintained, and some links may not work. Persons with disabilities having difficulty accessing this information should contact us at: Let us know the nature of the problem, the Web address of what you want, and your contact information.

Please go to for current information.

Patients with aortic dissection who have syncope are at high risk for life-threatening complications

Acute aortic dissection, which affects mostly hypertensive men between 40 and 60 years of age, occurs when blood seeps through a tear in the aorta, separating the outer and middle layers of the vascular wall. Many of these patients arrive at the emergency department (ED) suffering from chest pain or upper back pain. However, some patients may experience a brief loss of consciousness (syncope). These are the aortic dissection patients who are significantly more likely to have life-threatening complications such as stroke or cardiac tamponade (heart compression caused by the accumulation of fluid or blood in the pericardial sac), according to a study supported in part by the Agency for Healthcare Research and Quality (HS11540).

Physicians must be vigilant for these complications when patients suspected of acute aortic dissection arrive in the ED with syncope. A rapid bedside transthoracic echocardiogram should be performed in those with syncope to rule out cardiac tamponade, the most common cause of death in these patients, suggests Sanjay Saint, M.D., M.P.H., of the University of Michigan Medical School. Dr. Saint and colleagues used the International Registry of Acute Aortic Dissection to identify patients with acute aortic dissection at 18 referral centers in six countries and collected data on key clinical findings and outcomes via extensive questionnaires.

Overall, 13 percent of 728 patients had syncope, with 3 percent who had syncope having no symptoms of chest or back pain. Patients with syncope were more likely to die in the hospital than those without syncope (34 vs. 23 percent). They also were more likely to have cardiac tamponade (28 vs. 8 percent), stroke (18 vs. 4 percent), and other neurologic deficits such as coma (25 vs. 14 percent). However, nearly half of these patients had none of these complications as an explanation for their loss of consciousness.

See "Syncope in acute aortic dissection: Diagnostic, prognostic, and clinical implications," by Brahmajee K. Nallamothu, M.D., M.P.H., Rajendra H. Mehta, M.D., M.Sc., Dr. Saint, and others, in the October 15, 2002, American Journal of Medicine 113, pp. 468-471.

Return to Contents
Proceed to Next Article

The information on this page is archived and provided for reference purposes only.


AHRQ Advancing Excellence in Health Care