Doctors in Italy say they have carried out a transplant on a baby using the world's smallest heart, Reuters reported.
The transplant occured last month but was recently made public.
The 16-month-old baby was suffering from dilated myocardiopathy, a disease that weakens the heart and may cause the organ to fail.
Instead of a real heart, surgeons at Rome's Bambino Gesu hospital, used a titanium device that weighs eleven grams and can pump 1.5 liters of blood per minute through the body, reported Technology Review.
The device was invented by Robert Jarvik, an American doctor and inventor, who was consulted before the surgery.
The titanium heart, which will soon be replaced by a real heart, was only previously only tested on animals.
The young boy had been in intensive care since one-month of age.
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