Fatal Aortic Rupture from Nonpenetrating Chest Trauma

Abstract

A 22-year-old man died following a side impact blow in an automo-bile accident. Necropsy showed a large tear in the posterior wall of the aorta approximately 12 mm distal to the insertion of ligamentum arteriosum (Figures 1 and 2). Subadventitial hemorrhage was prominent in the descending thoracic aorta. Th e left pleural space contained large quantities of blood. Traumatic aortic rupture is the second most common cause of death in victims of blunt chest trauma from motor vehicle ac-cidents (1–3). Death usually (85%) occurs at the crash scene (2–4). Aortic rupture was responsible for about 15% of the deaths due to automobile accidents until seat belts and air bags were introduced. Seat belts seem to be more eff ective than air bags in reducing traumatic aortic injury (TAI) after blunt frontal motor vehicle crashes (5). Data from the National Automotive Sampling System Crashworthiness Data System between 1993 and 1998 indicated that seat belts reduced the incidence of TAI from 2.66% to 0.49% in crashes where an airbag did not deploy. Airbags alone do not signifi cantly reduce TAI in survivors of frontal motor vehicle crashes. Airbags are more eff ective in those using seat belts, together reducing the incidence from 0.49% to 0.29% (5). According to Christopher and colleagues (6), among patients with TAI, 71% were dri-vers, 23% were front-seat passengers, and 6% were back-seat passengers (6). Although most reports focused on frontal impact crashes, side impact accidents also are a major cause of TAI, especially after the introduction of seat belts (7, 8). Th e direc-tion of the crash impact was known in 672 patients from the National Automotive Sampling System registry between 1998 and 2002; among those, 57% were frontal, 18% were at the driver's side, 16% at the passenger's side, 2% in the rear, and 6% in a nonhorizontal direction (6).