Answer:
In some instances, the heart valves from pigs are used in heart-valve transplantation operations in humans. (Other options include human valves, bovine and artificial. )
Other organs from pigs are not adapted to function in the human body; organs from pigs are not routinely used in transplantation (because they do not work.) In some very rare instances, an animal organ may be used to bridge a gap (3-5 days) for a very ill patient, until a human organ can be found. This situation is exceptionally rare, and to reiterate, xenotransplantation is a very uncommon occurance.
Currently, there is research investigating how organs in pigs could be made more "humanised" so that they would be suitable for human use. Furthermore, making them suitable for human use from this method would also have the benefit of being able to "customise" the organ to the patient -the DNA could be made as similar as necessary to the structure of the patients original organ, which negates the need for toxic immunosuppressives post-transplant. However this technique is years away from being used in general transplantation.