Eisenmenger (I-sun-meng-uhr) syndrome is a complication of a heart defect that you're born with (congenital).

CNN: Eisenmenger syndrome

While hospitalized it was discovered that Moore had bleeding around his heart and a more severe complication involving his brain injury.

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The precocious 6-year-old was born with a congenital heart defect and had a complication with a tube inserted in his right leg, leading to an amputation above his knee.

CNN: Double amputee loses legs, finds a cause

None of the participants in the study had suffered a heart attack, death or other serious complication at a six-month follow-up after their procedure.

BBC: Scientists 'wake' heart muscle

It is not clear the additional expense and higher complication rate of the new gadget is worth it for all heart patients, doctors say.

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