The upgraded laboratory can now treat a wider range of heart problems more quickly and effectively.

MonashHeart director Professor Ian Meredith said the $1.2million upgrade included converting the laboratory to a high-resolution biplane laboratory, which meant surgeons could examine the heart from two angles at the same time.

Professor Meredith said the upgrades to the laboratory would make a huge difference to patients.

"It means we can do more precise procedures more quickly and efficiently, with less radiation exposure to the patient," he said.

"We're ideally positioned to do more complex structural heart treatments."

The upgrades also paved the way for MonashHeart to treat children and adolescents.

"In the past they had to go to the Royal Children's Hospital - and they still do until we get approval (to treat them) - but it paves the way."

The unveiling - attended by Health Minister Daniel Andrews - comes days after the state government announced a $250million upgrade for Monash Children's, which has bipartisan support.

Professor Meredith said the lab was the first piece in the puzzle for improving services to children in the area. "This is the first piece of technology paving the way for more complex heart procedures. We're grateful to the government and Department of Health for supplying us with it."