IMPACT OF ECHOCARDIOGRAPHIC OPTIMIZATION OF RESYNCHRONIZATION PACE-MAKER USING DIFFERENT PACING MODALITIES AND ATRIOVENTRICULAR DELAYS ON ACUTE HEMODYNAMIC RESPONSE AND LONG TERM PROGNOSIS

Cardiac resynchronization therapy (CRT) improves ventricular dyssynchrony and is associated with an improvement in life quality and prognosis.Aim. The aim of study was to examine acute hemodynamic changes with different of CRT device modalities throughout optimization procedure and its impact on one year prognosis.Material and methods. The study comprised 62 patients with severe left ventricular systolic dysfunction (LVEF 24,6±4,4%, QRS duration 154,71±14,92 ms, NYHA class III/IV 47/15) with implanted CRT device. After implantation and before discharge all the patients underwent optimization procedure guided by Doppler echocardiography. Left (LVPEI) and right (RVPEI) ventricular pre-ejection intervals, interventricular mechanical delay (IVD) and the maximal rate of ventricular pressure rise during early systole (max dP/dt) were measured during left and biventricular pacing with three different atrioventricular (AV) delays. Stroke volume derived from the left ventricular outflow tract velocity–time integral (VTI) of left ventricular outflow tract (LVOT VTI) was measured as well. After one year patients underwent clinical, echocardiographical examination and 6 minute walking test.Results. After CRT device optimization, optimal AV delay and CRT mode were defined. Left ventricular pre-ejection intervals changed from 175,4±21,5 to 142,6±16,7 (p < 0,01), RVPEI from 108,6±18,9 to 127,3±18,3 (p < 0,001), IVD from 71,3±14,8 to 24,7±7,6 (p < 0,001) and dP/dt from 532,2±74 to 675,2±111 (p < 0,001). Left ventricular outflow tract VTI increased after optimization procedure from 18±3,4 to 21±1,5 cm (p