Scar-dependent ventricular tachycardia (VT) is a serious and sporadic heart rhythm disturbance caused by scar tissue in the heart muscle, often resulting from a previous heart attack or genetic heart conditions. Treatment typically involves implanting a defibrillator to shock the heart back to a normal rhythm when needed or using a catheter to ablate (burn) the scar tissue that causes the abnormal rhythms. However, these treatments have significant drawbacks. Defibrillators can’t prevent the recurrence of abnormal rhythms, and repeated shocks can lead to patient discomfort, impacting their quality of life. On the other hand, identifying and treating the scarred areas in the heart can be difficult because scars can form at multiple sites, including deep within the heart, making them hard to identify. Surgeons often map the heart by inserting a catheter to detect electrical pulses that indicate abnormal areas, and sometimes they induce arrhythmias to help locate the problem. Once identified, the surgeon ablates the scar tissue, but complications and high recurrence rates are common if all affected areas are not found and treated.

Now, a new study by researchers at St George’s University of London (London, UK) introduces an innovative approach using computers to create a digital twin of the heart, which can effectively identify scar tissue deep inside the heart. This research, published in the journal Circulation, shows the potential of digital heart twins to revolutionize the treatment of scar-dependent VT, particularly in patients with a history of heart attacks or genetic conditions. The digital heart twin could serve as a non-invasive tool for locating the scarred regions responsible for abnormal rhythms, enabling cardiologists to treat these areas more efficiently and with greater precision.

In their study, the researchers tested whether digital heart twins could predict the locations of abnormal rhythms in patients with scar-dependent VT. Using advanced cardiac imaging and other data, they created computer models that replicated the hearts of 18 patients undergoing catheter ablation for this condition. The patients’ hearts were mapped using a catheter, and abnormal rhythms were induced to help locate problem areas. The digital models were then tested to see if they could predict rhythm disturbances similar to those experienced by the patients. The results showed that the digital heart twins predicted problematic areas with 41% more frequency of abnormalities compared to areas not flagged by the models, suggesting that these digital models could identify potential treatment sites without needing catheter mapping.

Moreover, the digital twins successfully predicted about 80% of the sites in patients’ hearts where electrical signals were slowed, a common sign near scar tissue. This method could reduce the likelihood of abnormal rhythms recurring and the need for additional treatments. The digital twin not only predicts current VT episodes but also forecasts potential future arrhythmias. While the effectiveness of using digital heart twins to guide catheter ablations has not yet been fully tested, the next step would involve a clinical trial comparing current VT ablation practices with a strategy guided by the digital twin from the beginning. However, implementing this procedure may be limited by the sophisticated technology required and the associated costs.

"People are now living with the consequences of heart attacks for many years, so the number of people who need procedures to treat these life-threatening abnormal heart rhythms is rising," said lead study author Dr. Michael Waight, a cardiology registrar at St George's University of London. "If digital twins were to become a reality, it could offer a safer and potentially more effective means of treatment."

The digital heart twin "gives you a road map of areas to focus on. It's an incredibly powerful advancement. It's really moving the field forward, making these procedures a lot more effective and more precise," said Dr. Dhanunjaya Lakkireddy, who was not involved in the research. "If you are able to successfully eliminate these areas that are potentially sites of ventricular tachycardias, you can reduce the time of the procedure and go precisely to the areas that are important with minimal unnecessary ablation. This could potentially improve overall morbidity and mortality with a higher success rate and result in dramatically improved patient outcomes." 

http://m.allmycbs.com/en/index.asp .