When there is heart failure that reduces the amount of blood/oxygen to the heart muscles with each heartbeat. Your father has concomitant medical issues associated with respiratory problems.
If the concomitant health issues are successfully treated, there may be some help with an implant of a pump for the heart failure. Former Vice President **** Cheney, 69, who underwent surgery recently to implant a pump to assist his heart, "may be only one step away from a heart transplant, according to cardiac experts". It can also be used as a permanent device.
Sorry to hear of the health problems your father has and thanks for sharing. Hope it works out for your father and there is improvement. Take care.