Painless acute aortic dissection. - Diagnostic, prognostic and clinical implications.-

Acute aortic dissection (AAD) classically presents as sudden, severe chest, back, or abdominal pain. However, there have been several documented cases presenting with atypical features. The clinical characteristics and outcomes of patients with painless AAD were investigated.

The study group comprised 98 patients (53 males, 45 females; 66 ± 12 years) with AAD admitted to hospital from 2002 to 2007: 16 patients (17%) had no pain (painless group) and 82 patients had pain (painful group). In 81% of the painless group and 70% of the painful group there was a type A dissection. The painless group more frequently had a persistent disturbance of consciousness (44% vs. 6%, P < 0.001), syncope (25% vs. 1%, P < 0.001) and a focal neurologic deficit (19% vs. 2%, P = 0.006) as presenting symptoms. Imaging study findings were not significantly different. Cerebral ischemia (50% vs. 1%, P < 0.001) and cardiac tamponade (38% vs. 13%, P = 0.01) were more frequent complications in the painless group. In-hospital mortality was not significantly different (19% vs. 15%). However, the painless group had a more unfavorable functional outcome on overall performance category (P < 0.001).

Painless AAD may be more frequent than previously reported. Painless AAD patients often present with a disturbance of consciousness or a neurologic deficit, and have a higher morbidity than painful AAD patients.