Primacor (milrinone) is a vasodilator/inotrope that is used in severe heart failure to improve symptoms. Potential side-effects include fatal arrhythmias and thus its use is strictly monitored. It is not uncommon for individuals awaiting heart transplant to require milrinone. It may be given either as a continous infusion or over a short period of time (sometimes refered to as a "milrinone tune-up". Milrinone does not improve survival but only improves symptoms in these individuals. You should continue to monitor your daily weights and symptoms and notify your doctor if there is a change in either of these.