Potential pitfalls in the diagnosis of aortic dissection

The primary objective of our study was to identify clinical issues contributing to delay in the diagnosis of nontraumatic aortic dissection.

Retrospective observational study.

A 425-bed community based, university-affiliated teaching hospital.

Medical records were analyzed for physiologic, clinical, and outcome variables in 32 consecutive patients who presented to our hospital with non-traumatic aortic dissection over a three-year period (1995-1997).

The mean time to diagnosis was 10.7 hours (range 0.5-72 hours). The time to diagnosis and clinical variables did not differ between type A and type B aortic dissections (8.7 vs 11.4 hours; P = 0.54). The diagnosis of aortic dissection was not entertained initially in 44% (14/32) of patients, leading to a significant delay in diagnosis compared to patients with suspected aortic dissection on admission (15.0 vs 4.5 hours; P = 0.008). Lack of a widened mediastinum on chest roentgenography (18.7 vs 6.6 hours; P = 0.026) and lack of hypertension (< 140/90 mmHg) at presentation (14.9 vs 7.1 hours; P = 0.03) were associated with a delayed diagnosis of aortic dissection as compared to presence of either finding. The presence or absence of chest or back pain, resting ECG changes, and a past medical history of hypertension did not correlate with time to diagnosis. There was a trend toward earlier diagnosis when the initial diagnostic modality was transesophageal echocardiography as compared to computed axial tomography (CAT) scan (7.7 vs 10.1 hours; P = 0.20).

Patients with aortic dissection are frequently normotensive and may lack typical chest roentgenographic findings at presentation. A high index of clinical suspicion for aortic dissection is essential to avoid potentially fatal delays in its diagnosis.