Exercise-induced XXXX : a substrate for @entity944 in athletes?

@entity1 @entity712 @entity944 @entity1184 @entity1283 @entity10804 @entity1540 @entity299 @entity1162 @entity943
@entity1283 is a general term signifying an increase in cardiac mass in response to applied stress. In mild, early @entity1184 , cardiac myocyte contractile performance may be normal or enhanced, whereas in severe @entity1184 associated with @entity712 , myocyte contraction is reduced in amplitude and increased in duration. In contrast to the varied contractile response, the duration of electrical excitation shows similar changes in both mild and severe @entity1184 . Action potential duration in mid-myocardial and sub-epicardial layers is increased, which is associated with @entity943 (in a similar manner to the @entity1162 from other causes), based on afterdepolarizations and enhanced @entity10804 . Single-cell studies following exercise training in animal models show that exercise-induced @entity1283 displays features similar to mild, compensated @entity1184 from other causes. Developed shortening of unloaded single cells is increased or unchanged, and developed force in single myocytes is enhanced. Action potential duration is increased, apart from in the sub-endocardial layer. As with mild @entity1184 from other causes, this will be pro-arrhythmic because of altered dispersion of repolarization and enhanced @entity10804 . Major abnormalities of the ECG in @entity1 include frequent and complex @entity1540 , ST segment changes and prolongation of repolarization. In this review a case is presented for regarding exercise-induced @entity1283 as being no different from mild @entity1283 resulting from other, pathological causes. The cellular electrophysiological changes are sufficient to account for many of the abnormalities of the ECG, including high-grade @entity1540 . @entity944 in trained athletes who have no evidence of specific @entity299 may be a direct consequence of @entity1283 and altered repolarization.
