Miniature beating human hearts have been grown by scientists at Abertay University.
They have been developed to try to find a cure for heart hypertrophy a form of heart disease that can lead to sudden death.
Made from stem cells, the tiny hearts are just 1mm in diameter and contract at around 30 beats per minute.
Although healthy to begin with, the scientists are using chemicals to simulate the physiological conditions that will make them become enlarged, due to abnormal growth of cells called cardiomyocytes.
Once diseased, the hearts are then treated with newly developed medications to see if they can prevent the damage from occurring.
Professor Nikolai Zhelev, who is leading the research, said: “Although human hearts have been grown in labs before, this is the first time it has ever been possible to induce disease in them.
“Heart hypertrophy can be hereditary, can be caused by diseases such as diabetes, or can be caused by doing too much strenuous exercise.
“The disease causes the heart muscle to thicken and stiffen and makes it harder for the heart to pump blood around the body.
“In some people, a life-threatening abnormal heart rhythm will develop and this is the most common cause of sudden death in young people.”
Prof Zhelev is hoping the miniature hearts could help to change that.
Biosensors are being used to track specific molecules to see where they are going in the hearts.
By working out which ones cause the heart to become hypertrophic, he has been able to target drugs at these molecules and prevent them from going down the path they would usually take.