Personalized heart digital twin models accurately detect substrate and functional abnormalities during ablation for scar-dependent ventricular tachycardia (VT), according to findings from a single-center study published Jan. 6 in Circulation.

Michael C. Waight, MBBS, BSc (Hons), MRCP, et al., conducted the first prospective study to evaluate the accuracy of personalized digital twin models to predict critical substrate abnormalities in VT. Using late gadolinium-enhanced cardiac MRI images, they generated a heart digital twin for 18 patients (17 were men) with ischemic and nonischemic cardiomyopathy undergoing catheter ablation for scar-dependent VT to predict substrate locations most likely to maintain reentrant arrhythmias.

The digital twin was then used to induce VTs, define their circuits and derive optimal ablation lesion sets that terminate all VTs. Invasive substrate mapping was performed and the digital twins were merged with the electroanatomical map. Electrogram (EGM) abnormalities and regions of conduction slowing were compared between digital twin-predicted and nonpredicted sites.

Results showed that EGM abnormalities were significantly more frequent in digital twin-predicted sites compared with nonpredicted areas (45.5% vs. 32.2%; p<0.001). Also, EGM duration was longer at predicted compared with nonpredicted sites (82.0±25.9 msec vs. 69.7±22.3 msec; p<0.001). On isochronal late activation mapping, digital twins correctly identified 21 of 26 (80.8%) deceleration zones.

Study findings also demonstrated that EGM behavior in response to stress during functional substrate mapping was particularly abnormal at predicted compared with nonpredicted sites, and areas of conduction slowing, essential for establishment of reentry, frequently arose at the predicted sites. EGM duration was also prolonged at predicted sites compared with nonpredicted sites.

"Digital twins represent a potential paradigm shift toward the application of personalized medicine in the treatment of arrhythmia," write the authors. Furthermore, they may "improve procedural success, reduce the risk of long-term arrhythmia recurrence, and allow a shorter, more targeted, ablation procedure, thereby reducing complications and length of hospital stay."