Why our hearts fail: research

Australian researchers have made several new heart failure discoveries in an innovative world-first project examining cryo-preserved human hearts, procured after transplantation, in the Sydney Heart Bank.

Scientists at the Heart Research Institute and The University of Sydney’s Charles Perkins Centre studied the molecules in hearts removed at the time of transplantation, revealing what happens inside them when they stop working.

“What’s really intriguing is that we were able to use human hearts donated over many years and curated in the Sydney Heart Bank, the world’s largest human heart bank based at the Charles Perkins Centre,” says Dr John O’Sullivan, cardiologist and Cardiometabolic Disease Group leader at the Heart Research Institute and Charles Perkins Centre. “Using this unique resource, we determined how the heart deals with injury and clotting, and how heart failure differs between men and women.”

The work is published in the prestigious international journal Nature Communications.

Heart failure is where the heart is unable to pump blood around the body. The two most common types of heart failure requiring heart transplantation are that caused by a heart attack, and that resulting from an enlarged and weakened heart. Over half a million Australians have heart failure, with 61,000 new cases diagnosed each year, costing $2.7 billion per annum. Progress in understanding the molecular underpinnings of heart failure has been hampered by lack of access to human heart tissue.

The Heart Research Institute and Charles Perkins-led research teams used the Sydney Heart Bank, located at the Charles Perkins Centre, directed by colleague Dr Sean Lal, Clinical Academic Cardiologist at the University of Sydney and Royal Prince Alfred Hospital, to study 44 failing hearts that have been removed during transplantation at St Vincent’s Hospital over the past 30 years.

“We used advanced techniques to screen this heart tissue and measure thousands of proteins and other small molecules,” explains Dr O’Sullivan, joint senior author on the paper with Dr Lal. “We then compared hearts with advanced heart failure with tissue from non-diseased hearts, matched for age, gender, and BMI, for a deep understanding of how they differ.”

Researchers found changes in many important processes in the heart, including mechanisms that generate energy for the heart, mechanisms that deal with injury, clotting mechanisms, and processes that maintain structural integrity.