3-D Virtual Heart Assessment Tool Accurately Pinpoints Fatal Arrhythmia

A team of Johns Hopkins University researchers has created a revolutionary, non-invasive 3-D virtual heart assessment tool that can detect life-threatening arrhythmia for cardiac patients who would require a defibrillator.

This device has been found to be more accurate in predictions than the blood pumping measurements that are currently employed.

"Our virtual heart test significantly outperformed several existing clinical metrics in predicting future arrhythmic events," said Natalia Trayanova of Johns Hopkins University and senior author of the report. "This non-invasive and personalized virtual heart risk assessment could help prevent sudden cardiac deaths and allow patients who are not at risk to avoid unnecessary defibrillator implantations."

Trayanova and her team used magnetic resonance imaging (MRI) records of patients to arrive at their conclusion. They examined patients that had managed to live through a heart attack but had cardiac tissue that was damaged and also enhanced the possibility of "deadly arrhythmias."

After studying 21 patients, the scientists had an ejection fraction, which could assess how much blood gets pumped out of the heart.

The 41 participants had received implantable defibrillators to measure their ejection fractions. But the score was found to be not reliable in predicting patients at the risk of cardiac death.

With pre-implant MRI scans, the team could create an alternative method to get the scores through a 3-D virtual heart assessment tool. They then created patient-specific digital replicas of organs and gave them life with the help of computer modeling techniques that factored electrical processes in the heart and inter-cellular communication.

They hence got a "virtual heart" offering a non-invasive way to assess the risk of sudden cardiac death due to arrhythmia. It is called the virtual heart arrhythmia risk predictor (VARP).

It predicted arrhythmia in patients four-to-five times better than other risk predictors.

"We demonstrated that VARP is better than any other arrhythmia prediction method that is out there," Trayanova said. "By accurately predicting which patients are at risk of sudden cardiac death, the VARP approach will provide the doctors with a tool to identify those patients who truly need the costly implantable device and those for whom the device would not provide any life-saving benefits."

"With the technique used in this study, we were able to create a personalized, highly detailed virtual 3-D heart, based on the patient's specific anatomy," added Katherine Wu, also of Johns Hopkins University and co-author of the study. "Then, we were able to test the heart virtually to see how irritable it is under certain situations. We could do all this without requiring the patient to undergo an invasive procedure. This represents a safer, more comprehensive and individualized approach to sudden cardiac death risk assessment."

The findings were published on May 10, 2016, in the journal Nature Communications.