Real-time three dimensional tte in quantification of left ventricular dyssynchrony

Background. The main problem in the patient selection for cardiac resynchronization therapy (CRT) is the lack of unified approaches to the definition of mechanical dyssynchrony (MD) and selection criteria. Objective. To reveal the dependence of the criteria of dyssynchrony in patients on the method and point of stimulation and to reveal the correlation of these data with the width of the QRS complex and the percentage of global two-dimensional longitudinal deformation. Design and methods. The study involved 12 patients with drug-compensated CHF of class II-IV, LVEF< 35 % and a QRS duration >130 ms, having CRT indications. All patients were intraoperatively injected with a retrograde transaortically guided electrode. During stimulation of each point (88 points), transesophageal Echo-KG (PE Echo-KG) was performed. TomTec and Philips Qlab 3DQ Advanced software was used for data analysis. Results. The segmental excursion and myocardial contractility differed significantly depending on the stimulation point. A moderate inverse correlation was found between ExcAvg, LVEF and QRS duration. There were a direct correlation of the SDI-16 and the QRS duration was shown, and an inverse correlation of SDI-16 with ExcAvg and LVEF. 2D longitudinal global strain was inversely correlated with the EF. Conclusion. The technique is useful for regional LV myocardial contractility assessment and patient selection and comparison of alternative approaches to LV pacing to improve response to CRT.