The surgeons implanted artificial valves inside the leaky ones whilst the hearts continued to beat rather than stopping them and using a bypass.
Both patients had a condition called mitral valve regurgitation, where the valve between the left ventricle and left atrium isn't able to close properly making blood flow back into the lungs instead of to the aorta.
Suitable for patients not suitable for surgery
Cardiologist Dr Paul Jansz said he hoped the new approach would offer hope for heart patients who were not suitable candidates for surgery.
"The significant thing is that we don't have to stop the heart, so we don't have to put the patient through all the extra rigors of heart surgery," Dr Jansz said.
The first operation took place at Sydney's St Vincent's Hospital in November last year, and after six weeks the patient did not experience complications.
A second operation took place earlier this week when a team of 16 specialists, including surgeons, echocardiographers, anaesthetists, nurses and industry engineers – who designed the valves – took part.
The device, shaped like a flower, crafted from the heart tissue of a pig, is sewn into a metal cage and secured to the heart's apex with string.
Fellow cardiologist Dr David Muller said the treatment was much less invasive for patients and much more secure within the heart once implanted.
"The unique part of this device is that it's tethered to the apex of the heart."
"There should be no downside to putting it in and trying it.
"It's a … much better tolerated procedure for patients who are not well."
