Allograft Dysfunction in Heart Transplant

This study is looking at heart transplant recipients to better understand why some transplanted hearts stop working well over time — a condition called allograft dysfunction. Researchers are using a special type of MRI to assess the health of the transplanted heart. **You may be eligible if...** - You are 18 years or older - You received a heart transplant at least 3 months ago **You may NOT be eligible if...** - You had a confirmed episode of acute heart rejection in the past 3 months - You have had a recent heart attack or signs of heart blockage in the past 3 months - You have uncontrolled asthma or COPD (chronic lung disease) - You have a history of major seizures - You have certain types of heart rhythm problems (second or third degree heart block, sick sinus syndrome) - You have a pacemaker or other implanted electronic device that is not compatible with MRI - Your kidney function is significantly reduced (GFR below 30) - You have had a serious allergic reaction to MRI contrast dye or certain heart stress medications - Your blood pressure or heart rate is outside safe ranges - You have severe claustrophobia Talk to your doctor to see if this trial is right for you.