Aortic aneurysm and hypotension were among the clinical features identified as putting patients at high risk for acute aortic dissection in a case-control study.
Robert Ohle, MSc, MA, MB, FRCPC, from the department of emergency medicine, the Ottawa Hospital Research Institute, University of Ottawa, Ontario, Canada, and colleagues conducted a historical matched case-control study of adults presenting to two tertiary care EDs or one regional cardiac referral center with possible acute aortic dissection between 2002 and 2014.
The researchers analyzed 194 patients with nontraumatic acute aortic dissection confirmed by CT or echocardiography and 776 age- and sex-matched controls who had a triage diagnosis of truncal pain but no clear diagnosis upon basic investigation (mean age, 65 years; 67% men).
Ohle and colleagues found that acute aortic dissection could be ruled out by absence of abrupt-onset pain (sensitivity = 95.9%; negative likelihood ratio = 0.07; 95% CI, 0.03-0.14).
They determined the following factors can help rule in a diagnosis of acute aortic dissection:
- presence of tearing/ripping pain (specificity = 99.7%; positive likelihood ratio = 42.1; 95% CI, 9.9-177.5);
- aortic aneurysm (specificity = 97.8%; positive likelihood ratio = 6.35; 95% CI, 3.54-11.42);
- hypotension (specificity = 98.7%; positive likelihood ratio = 17.2; 95% CI, 8.8-33.6);
- pulse deficit (specificity = 99.3%; positive likelihood ratio = 31.1; 95% CI, 11.2-86.6);
- neurologic deficits (specificity = 96.9%; positive likelihood ratio = 5.26; 95% CI, 2.9-9.3); and
- a new murmur (specificity = 97.8%; positive likelihood ratio = 9.4; 95% CI, 5.5-16.2).
“Patients with one or more high-risk feature ... should be considered high risk, whereas patients with no high-risk and multiple low-risk features (absence of abrupt-onset pain, history of ischemic heart disease and diabetes) are at low risk for acute aortic dissection,” the researchers wrote.
History of ischemic heart disease decreased the probability of an acute aortic dissection diagnosis, but this was “likely due to it being a risk factor for an alternative diagnosis such as acute coronary dissection,” Ohle and colleagues wrote.
“Ohle [and colleagues] have done a great job at telling us how acute aortic dissection presents to emergency departments,” Lane McNeil Smith, MD, PhD, assistant professor, Lexington Emergency Medicine, Wake Forest Baptist Health, said in a press release. “Are we finally on the verge of a decision rule for this disease that improves our miss rate without ballooning nontherapeutic imaging and costs? This study is a step in the right direction and the authors are in a good position to find the right balance of improved accuracy and increased cost.” – by Erik Swain
Disclosures: The authors and Smith report no relevant financial disclosures.