When a patient weighs only 6.4 pounds, certain procedures can get tricky. That was the case for Buttercup, an 11-month-old Morkie (Maltese-yorkie mix), who suffered from a deadly congenital cardiac defect. At most hospitals, Buttercup would have had to go through a more invasive and painful surgery to fix her condition, but the cardiology team at the Cornell University Hospital for Animals performed a highly unusual procedure to keep her at her healthiest. College of Veterinary Medicine/Provided Buttercup, an 11-month-old Morkie, had a common congenital heart condition, which surgeons at the Cornell University Hospital for Animals fixed with a rare procedure.