Using stem cells and smart machines to warn of heart problems

Despite advances in treatments in recent years heart disease remains the leading cause of death in the US. It accounts for one in three deaths in this country, and many people are not even aware they have a problem until they have a heart attack.

One of the early warning signs of danger is a heart arrhythmia; that’s when electrical signals that control the hearts beating don’t work properly and can result in the heart beating too fast, too slow, or irregularly. However, predicting who is at risk of these arrhythmias is difficult. Now new research may have found a way to change that.

A research team at the Institute of Molecular and Cell Biology in Singapore combined stem cells with machine learning, and developed a way to predict arrhythmias, with a high degree of accuracy.

The team used stem cells to create different batches of cardiomyocytes or heart muscle cells. Some of these batches were healthy heart cells, but some had arrhythmias caused by different problems such as a genetic disorder or drug induced.

They then trained a machine learning program to use videos to scan the 3,000 different groups of cells. By studying the different beating patterns of the cells, and then using the levels of calcium in the cells, the machine was able to predict, with 90 percent accuracy, which cells were most likely to experience arrhythmias.

The researchers say their approach is faster, simpler and more accurate than current methods of trying to predict who is at risk for arrhythmias and could have a big impact on our ability to intervene before the individual suffers a fatal heart attack.

The research was published in the journal Stem Cell Reports.

The California Institute for Regenerative Medicine has invested more than $180 million in more than 80 different projects, including four clinical trials, targeting heart disease.

CIRM funded study uses drug development in a dish for treatment of heart arrhythmias

Image Credit: Center for Disease Control and Prevention (CDC)

Cardiac (heart) arrhythmias occur when electrical impulses that coordinate your heartbeats don’t work properly, causing your heart to beat too fast, too slow, or in an irregular manner. In the U.S. alone, almost one million individuals are hospitalized every year for heart arrhythmias. Close to 300,000 individuals die of sudden arrhythmic death syndrome every year, which occurs when there is a sudden loss of blood flow resulting from the failure of the heart to pump effectively. Unfortunately, drugs to treat arrhythmias have liabilities and several drugs have been pulled from the market due to serious side effects. Mexiletine is one potential drug for heart arrhythmias that has liabilities and potential side effects.

That is why a CIRM funded study ($6.3 million) conducted by John Cashman, Ph.D. at the Human BioMolecular Research Institute in San Diego looked at re-engineering mexiletine in a way that the drug could still produce a desired result and not be as toxic.

The study used induced pluripotent stem cells (iPSCs), a type of stem cell “reprogrammed” from the skin or blood of patients that can be used to make virtually any kind of cell. iPSCs obtained for the study were from a healthy patient and from one with a type of heart arrhythmia. The healthy and arrhythmia iPSCs were then converted into cardiomyocytes, a type of cell that makes up the heart muscle.

By using their newly created healthy cardiomyocytes and those with the arrhythmia defect, Cashman and his team were able to carry out drug development in a dish. This enabled them to attempt to lessen drug toxicity while still potentially treating heart arrhythmias. The team was able to modify mexiletine such that is was less toxic and found that it could potentially decrease a patient’s risk of developing ventricular tachycardia (a fast, abnormal heart rate) and ventricular fibrillation (an abnormal heart rhythm), both of which are types of heart arrhythmias.

“The new compounds may lead to treatment applications in a whole host of cardiovascular conditions that may prove efficacious in clinical trials,” said Cashman in a press release. “As antiarrhythmic drug candidate drug development progresses, we expect the new analogs to be less toxic than current therapeutics for arrhythmia in congenital heart disease, and patients will benefit from improved safety, less side effects and possibly with significant cost-savings.”

The team hopes that their study can pave the way for future research in which cells in a dish can be used to lessen the toxicity of a potential drug candidate while still producing a desired result for different diseases and conditions.

The full study was published in ACS Publications.