Operation on Fetus's Heart Valve Called a 'Science Fiction' Success.

Reports on how doctors at Children's Hospital, Boston, Massachusetts, corrected a deadly heart defect in a fetus. Comments of cardiologists Stanton Perry and Audrey Marshall, who operated to open a narrowed valve in the fetus' heart; Information on the disorder, hypoplastic left heart syndrome, which is fatal if untreated; Details of the operation; How this is the first time the approach has worked in the United States; Outlook for the child, who was born six weeks early.