Volkov D. Routes of permanent cardiac pacing optimization

The research is dedicated to determination of reasons of unsatisfactory results in electrophysiological treatment of cardiac conduction disorders and related chronic heart failure (CHF), as well as routes to optimize the implanting procedure, programming for pacemakers (PM) and cardiac resynchronization therapy (CRT) devices and patients’ follow-up. Variants of venous, coronary sinus and heart chambers anatomy in prospective of technical challenges in access, guiding and implantation of PMs’ and CRTs’ leads have been identified and systemized. Unusual anatomy variants are causes of failure in primary access and cannulation of the veins, difficulties in guiding guidewires and leads, dislodgement of leads and impossibility of precise right ventricular (RV) mapping. In this regard, in cases of "complex" anatomy, the incidence of intra- and postoperative complications increases compared to patients with normal anatomy: 19.2% and 7.2%, respectively (χ2 = 8.829; p = 0.003).It was revealed that the optimal RV lead implantation site is area of interventricular septum (IVS) with the least thickness, which in most cases is on the edge of its middle and lower parts. As RV lead was located in the thinnest area of IVS, the greatest reduction in paced QRS duration was achieved; one year after followed by reduction of number of patients with higher NYHA chronic heart failure (CHF) functional class accompanied by decreasing signs of impaired LV function including markers of dissynchrony (Local and Global Longitudinal Strain).