Aortic dissection and sport: physiologic and clinical understanding provide an opportunity to save young lives.

Understanding the relationship between acute type A aortic dissection and sport is crucial to prevent sudden cardiac death in seemingly healthy young individuals. Aerobic exercise produces only a modest rise in arterial blood pressure (140-160 mmHg) except at the highest levels of exertion, at which pressures between 180-220 mmHg are reached. Weight training, on the other hand, routinely produces acute rises in blood pressure to over 300 mmHg. This presents a danger for individuals with an unknown aortic aneurysm; the deteriorated mechanical properties of the aortic wall resulting from aneurysmal enlargement increase the susceptibility to aortic rupture when the high wall coincident with exertion exceeds the tensile strength of the aortic wall. Investigations by our group into the inciting events leading up to dissection have demonstrated a causal link between extreme exertion, severe emotional stress, and acute type A aortic dissection. Since aortic enlargement is often unknown to persons participating in weight training, especially in the youth population, a ìSnapShot Echocardiogramî screening program is been proposed; such a pilot program will raise awareness of the importance of pre-participation cardiac screening and allow for early detection of aneurysms as a means of preventing this ìsilent killerî from striking. As strong supporters of the numerous benefits of weight training, we encourage this activity in individuals without aneurysm; without aneurysm, wall tension does not reach dangerous levels, even at extremes of exertion. For individuals with known aortic dilatation, we recommend a program that limits their lifting to 50% of body weight in the bench press or equivalent level of perceived exertion for other specific strength exercises.