Predictive analysis of Cardiac Resynchronization Therapy response by means of the ECG

Aims: Cardiac Resynchronization Therapy (CRT) is an effective treatment for heart failure patients with moderate to severe symptoms. Unfortunately, a significant proportion of patients (up to 35%) do not respond to CRT (patients called “non-responders”). This results in a large cost-effectiveness relation for heart failure treatment. This study aims to assess the prediction response to CRT by means of analysing the ECG. Methods: We retrospectively analysed the surface ECG and QRS previous to CRT implantation in 45 consecutive patients with dilated (27) or ischemic (18) cardiomyopathy. We extracted the QRS and then processed a measure of energy of a discrete version of the Stockwell Transform. This feature was used to discern non-responder patients to CRT. Results: 10 out of 45 patients were clinically judged as non-responders to CRT. We observed that, on average, non-responders presented significant lower values for this energy measure than patients who responded favorably to the therapy (with median values 95538 vs. 48516 for responders and non-responders, p-value < 0.05). Using energy in the spectrum as feature to predict patients' response, as well as mean duration of QRS complexes, our obtained performances for a linear least-squares classifier were: accuracy (77.78%), sensitivity (80%), specificity (70%). Conclusion: The current study presents a novel approach to obtain early predictions of potential candidates to CRT in patients suffering from heart failure by means of calculating the energy of the ECG, which may open a door to reduce and try to minimize the number of CRT treatments with unsuccessful results.