Early prediction of cardiac resynchronization therapy response by non-invasive electrocardiogram markers

Abstract

Cardiac resynchronization therapy (CRT) is an effective treatment for those patients with severe heart failure. Regrettably, there are about one third of CRT "non-responders", i.e. patients who have undergone this form of device therapy but do not respond to it, which adversely affects the utility and cost-effectiveness of CRT. In this paper, we assess the ability of a novel surface ECG marker to predict CRT response. We performed a retrospective exploratory study of the ECG previous to CRT implantation in 43 consecutive patients with ischemic (17) or non-ischemic (26) cardiomyopathy. We extracted the QRST complexes (consisting of the QRS complex, the S-T segment, and the T wave) and obtained a measure of their energy by means of spectral analysis. This ECG marker showed statistically significant lower values for non-responder patients and, joint with the duration of QRS complexes (the current gold-standard to predict CRT response), the following performances: 86% accuracy, 88% sensitivity, and 80% specificity. In this manner, the proposed ECG marker may help clinicians to predict positive response to CRT in a non-invasive way, in order to minimize unsuccessful procedures.

Useful assessment of myocardial viability and dyssynchrony from gated perfusion scintigraphy for better qualification for resynchronization therapy. Part 3

“…Resynchronization therapy reduces mortality and severity of heart failure symptoms in patients with ejection fraction below or equal to 35% and with prolonged QRS complex duration on the resting ECG [ 8 – 10 ]. Unfortunately, it has been shown that about a third of people meeting the criteria for CRT implantation do not respond to resynchronization therapy, which limits the usefulness and cost-effectiveness of this medical procedure [ 11 – 13 ].…”