(AP) — A 2-pound Michigan newborn dubbed "Mighty Girl" by her parents is one of the smallest babies in the world to undergo a heart procedure to open up a blocked artery caused by a congenital defect. Dr. Joseph Vettukattil, who performed the pulmonary balloon valvuloplasty at DeVos Children's Hospital in Grand Rapids, has done 300 such procedures over 20 years, but the smallest patient on which he performed it was 4 pounds. In follow-up checks with health specialists, Alexandra slipped further down the growth track. In the neonatal intensive care unit, Alexandra remains active, kicking her legs and pulling on tubes.