Anticipatory Valsalva-type response as a contributory factor in low impact blunt traumatic aortic rupture

Abstract

Despite a range of trauma scenarios, fatal blunt injury to the chest commonly results from rupture of the aorta at the isthmus. The aetiology whereby blunt traumatic aortic rupture predictably occurs at the isthmus remains uncertain, and although a number of theoretical mechanisms have been proposed, no direct evidence exists supporting any one process. In addition, it is uncertain why some individuals who are exposed to relatively minor blunt trauma, sustain this injury. We have previously developed a finite element model in an attempt to simulate the large number of interdependent variables in this complex cardiopulmonary dynamic. This has led us to the conclusion that the physiological state at the moment of impact is important and that there may be a point of susceptibility to low impact blunt traumatic rupture in the cardiopulmonary dynamic. This manuscript suggests and develops an hypothesis based on the putative contribution of an anticipatory Valsalva-type response at the moment of impact and discusses possible mechanisms on how this might contribute to low impact blunt traumatic aortic rupture in individuals who sustain relatively minor trauma.