Cardiac allograft vasculopathy (CAV) is a coronary artery disease, but unlike the common type where plaque clogs the arteries, in this case the lining of the blood vessels starts to thicken and close in. CAV is discovered and monitored with coronary angiography (left heart catheterization), sometimes with the addition of an IVUS (intravascular ultrasound) catheter, usually annually or semi-annually. According to the International Society for Heart and Lung Transplantation, about one-third of patients will be diagnosed with CAV within the first five years after heart transplant. Who gets it is not well understood, but probably often has to do with conditions during surgery (including such things as how quickly the heart perfuses) and might be exacerbated by post-transplant conditions such as rejection or certain infections, such as CMV - that is, mostly things you can't do anything about other than trying to stay healthy. Because the heart is deneverated (nerves cut) at transplant, there is no pain or symptoms, so (gulp!) it presents as silent myocardial ischemia (blockage of blood flow to the heart) leading to heart failure or sudden death. Treatment options are limited. The first step is a change in medications, because some (like everolimus) can help stop the progression. Depending on where in the blood vessel it occurs, it can occasionally be treated with stents or bypass grafting, but if it progresses, generally the only cure is a new heart transplant. Scary stuff, but it doesn't progress in everyone (sometimes even reverses and goes away), and can be monitored at annual check-ups to make sure all stays well. That's always the hope!