Situs Inversus Totalis is a rare condition in which the organs of the body are placed in a mirror-image of the normal positioning. Specifically, the chest and abdomen organs are positioned on the right side of the body instead of its normal locations on the left. 

The heart, the primary chest organ, is located in the right chest also in contrast to its usual position in the left. Situs Inversus Totalis patients have all of their chest and abdomen organs reversed. An interesting point is that, in x-ray tests, these organs will appear in a mirror-image.

This condition is present at birth and occurs once in about every 6,000 to 8,000 births. 

 Source of Picture: http://science.howstuffworks.com/life/human-biology/reversal-of-organ1.htm  This picture shows the normal organ placement specifically compared to the positioning of a person with Situs Inversus Totalis.  

 Source of Picture: http://science.howstuffworks.com/life/human-biology/reversal-of-organ1.htm 

This picture shows the normal organ placement specifically compared to the positioning of a person with Situs Inversus Totalis.