Irish-based scientists have for the first time measured the fatigue strength of the chord-like tendons in the heart or heart strings.
The research on chordae tendineae will help scientists to understand how much repeated stress the tendons can take before rupturing.
This in turn should help understanding of the problems that disease and age can lead to in this important part of the heart.
The heart-strings study was carried out by the researchers at the Advanced Materials and BioEngineering Research Centre (AMBER), based at Trinity College Dublin.
Enabling normal blood flow, the chords live in the mitral valve, which lies between the left atrium and left ventricle in the heart.
One of the leading causes of leaking valves in the heart is the rupturing of these chords.
The condition can cause high blood pressure, tiredness, dizziness and chest pain and, in extreme chronic cases, can lead to heart failure.
Published in the journal Acta Biomaterialia the study looked at how much pressure the chords could take before snapping.
"These results are important because although there are predictor scales or models correlating stress levels with specific diseases, we have to date been missing the link relating those stress levels to the time before rupture occurs," said Professor Bruce Murphy, Investigator at AMBER and Deputy Director of the Trinity Centre for Bioengineering in a statement.
"With our study we have completed this missing link," he added.
The researchers will now go on to measure the breaking strain of other types of natural and synthetic chords to establish which might be useful in future heart valve transplants.
Man-made valves and those from pig hearts are already used for such transplants.
Pig valves degrade quickly after transplantation though, so the team are to test what effect treating them prior to the transplant can have.
