CineECG Repolarization Gradients Predict Acute Hemodynamic Response in CRT Patients.

Introduction: A variable proportion of non-responders to cardiac resynchronization therapy (CRT) warrants the search for new approaches to optimize the position of the left ventricular (LV) lead and the CRT device programming. CineECG is a novel ECG modality proposed for the spatial visualization and quantification of myocardial depolarization and repolarization sequences.

Objective: The present study aimed to evaluate CineECG-derived parameters in different pacing modes and to test their associations with acute hemodynamic responses in CRT patients.

Methods and results: CineECG was used to construct the average electrical path within the cardiac anatomy from the 12-lead ECG. CineECG and LV dP/dt max were tested in 15 patients with nonischemic dilated cardiomyopathy and left bundle branch block (QRS: 170 ± 17 ms; LVEF: 26 ± 5.5%) under pacing protocols with different LV lead localizations. The CineECG-derived path directions were computed for the QRS and ST-T intervals for the anteroposterior (X_h), interventricular (Y_h), and apicobasal (Z_h) axes. In a multivariate linear regression analysis with adjustment for the pacing protocol type, the ST-T path direction Y_h was independently associated with the increase in dP/dt max during CRT, [regression coefficient 639.4 (95% confidence interval: 187.9-1090.9), p = 0.006]. In ROC curve analysis, the ST-T path direction Y_h was associated with the achievement of a 10% increase in dP/dt max (AUC: 0.779, p = 0.002) with the optimal cut-off > 0.084 (left-to-right direction) with sensitivity 0.67 and specificity 0.92.

Conclusion: The acute hemodynamic response in CRT patients was associated with specific CineECG repolarization sequence parameters, warranting their further testing as potential predictors of clinical outcomes.