Arrhythmias are irregular heartbeats that can lead to sudden death, which doctors currently detect and address by installing a tiny defibrillator that jolts the organ back to its normal rhythm. But is there a way that doctors can decide when this costly, invasive electrical implant is actually necessary?
Researchers from Johns Hopkins University developed a non-invasive, computer-generated “virtual heart” to accurately predict the risk of sudden cardiac death and need for a defibrillator implant.
The team claimed that their 3D simulation – a proof-on-concept study – produced more accurate forecasts than the blood pumping measurement currently used by doctors. Their model is devised from distinctive magnetic resonance imaging (MRI) heart scans of subjects who incurred damage in their cardiac tissue post-heart attack.
"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,” reported study senior author and Professor Natalia Trayanova.
The system dubbed as Virtual-heart Arrhythmia Risk Predictor (VARP) used MRI scan results of 41 patients to create patient-unique digital simulations of damaged hearts. The researchers factored in the heart’s geometry, the distinct impact of scar tissue from the cardiac attack, and the way that electrical waves moved through the organ.
VARP results showed that subjects who emerged positive for arrhythmia risks had four times the risk of developing irregular heartbeats than those individuals who tested negative. The technology also performed four to five times greater than other methods predicting the occurrence arrhythmia, namely ejection fraction and a range of invasive methods.
Study co-author and Cardiologist Dr. Katherine Wu called it groundbreaking, particularly for allowing cardiologists to make use of all possible data in providing individualized care.
“[W]e were able to create a personalized, highly detailed virtual 3D heart, based on the patient's specific anatomy,” she said, adding that they can now gauge how “irritable” the heart is under specific situations without introducing an invasive operation.
The team now aims to conduct further research on these personalized virtual hearts, but this time involving bigger patient groups.
British Heart Foundation Medical Director Peter Weissberg highlighted the benefits of implantable defibrillators but confirmed that they are expensive and can entail complications at times.
“We recognize the need to minimize the negative effects of [implants] on people’s emotional and physical wellbeing,” he said in a Guardian report, echoing the need for a larger follow-up to the U.S. study.
The findings were published May 10 in the journal Nature Communications.
