Hypokinesis and akinesis areas are those areas that contribute little or nothing to the contraction of the heart and are often the result of formed scar tissue in the heart muscle after an MI.
As your husband has had two MI's, it is not so very surprising that those areas are found.
Luckily for your husband, the area's of hypo/akinesis are in locations that do not affect his EF very much.
An EF of 50-55% is only just outside the normal range of 55-70%.