PO-03-008 CORRECTION OF DYSSYNCHRONY BY CONDUCTION SYSTEM PACING: RESULTS OF LEVEL-AT TRIAL

Abstract

Correction of dyssynchrony measured with echo strain in conduction system pacing (CSP) vs biventricular pacing (BIVP) has not been reported. Our purpose was to compare echocardiographic dyssynchrony correction and strain improvement during follow-up between CSP and BIVP. A treatment received analysis was performed in patients included in the LEVEL-AT trial (NCT04054895) (n=29 CSP; BIVP 40). Patients were evaluated at baseline (ON and OFF programming) and at 6 and 12 months. All echocardiograms were completed by operators blinded to the type of device implanted. Intraventricular (septal flash), interventricular (difference between left and right ventricular outflow times), and auriculoventricular (diastolic filling time) dyssynchrony, as well as strain parameters (septal rebound, global longitudinal strain (GLS), and Risum pattern (typical left bundle branch contraction pattern)) were analyzed. 32% (22/69) were women; baseline LVEF was 27.5 ± 7% and left ventricular end-systolic volume (LVESV) 138 ± 77ml without differences between groups. At the 12-month follow-up, there were no differences in CSP vs. BIVP in LVEF (45.8 ± 10% vs. 42.7 ± 12%, p=0.25) and LVESV (81.5 ± 41 ml vs. 101.7 ± 56 ml, p=0.08). Longitudinal analyses showed that the improvement of all echocardiographic dyssynchrony parameters over time (p<0.001) was similar between groups (Table 1 and Fig 1A). A representative example of GLS at baseline and follow-up is shown in Figure 1B. GLS acute correction significantly correlated with LVEF (Fig 1C) and LVESV at the 12-month follow-up. CSP and BIVP provided similar dyssynchrony and strain correction over time. Acute strain correction predicted ventricular remodeling at 12 months follow-up.Tabled 1Table 1. (PO-03-008)Conduction system pacingBiventricular pacingEffects15 days OFF12 Months15 days OFF12 MonthsGroupTimeInteraction(Group*Time)Categorical variablesAdjusted prevalence +/- SEAdjusted prevalence +/- SEp-valueSeptal rebound0.769 +/- 0.0830.150 +/- 0.080.763 +/- 0.070.312 +/- 0.0820.13<0.0010.77Septal flash0.759 +/- 0.0790.310 +/- 0.0860.750 +/- 0.0680.108 +/- 0.0510.10<0.0010.49Risum pattern0.919 +/- 0.0730.0150 +/- 0.0210.84 +/- 0.1000.070 +/- 0.0590.81<0.0010.48Quantitative variablesAdjusted mean +/- SEAdjusted mean +/- SEp-valueGlobal longitudinal strain, %-9.62 +/- 0.68-11.28 +/- 0.73-8.69 +/- 0.57-11.28 +/- 0.590.32<0.0010.55Diastolic filling time, %47.6 +/- 1.5753.2 +/- 1.5746.0 +/- 1.3448.8 +/- 1.370.10<0.0010.57Difference in left and right ventricular outflow times, ms45.7 +/- 3.4816.6 +/- 3.4835.5 +/- 2.9621.4 +/- 3.110.76<0.0010.06Treatment received longitudinal analysis comparing CSP and BiVP in LEVEL-AT trial. Treatment effect over time but not different between groups. SE: standard error. Open table in a new tab