Abstract 2890: A novel method for Non-Invasive programming of Atrioventricular and Ventriculo-Ventricular delays of Cardiac Resynchronization Devices
Background: Optimization of cardiac resynchronization therapy (CRT) devices has been shown to provide incremental improvement in cardiac function and patient (pt) functional class. Routine application of echo-guided optimization is however limited due to time and expertise required. SphygmoCor (SCor) device (AtCor Medical) can measure left ventricular (LV) systolic function as ejection duration (ED) via applanation tonometry of the radial artery (aa). We studied if LV ED by SCor will correspond with echo Doppler parameters of cardiac function and synchrony during atrioventricular (AV) and ventriculo-ventricular (VV) pacemaker optimization.
Methods: We performed blinded simultaneous echo Doppler and SCor radial aa tonometry at different AV (40–300 ms), and VV delays (nominal, LV 20–40 ms, or RV 10–20 ms), A-pacing and A-sensing in 70 pts (67±14 yrs, 58 M), LVEF 33%±6%, 4±6 weeks post CRT.
Results: 510 measurements (mean of 6/pt) of echo Doppler and SCor radial aa pulse waveform were made at above pacemaker settings. Correlation of SCor radial aa ED with echo Doppler variables was as follows: Pulsed wave (PW) Doppler echo systolic ejection period r=0.79, p<0.001, PW mitral inflow filling time, r=0.45, p<0.001, LV outflow velocity times integral r=0.36, p<0.001and myoacardial performance index, r=0.39, p=0.01. Using Echo LV ED as gold standard, the sensitivity and specificity of SCor ED for correctly predicting the right AV and VV setting was 73% and 75%. Optimal VV delay was concordant between echo and SCor in 85% pts. Optimal AV delay was concordant between echo and SCor in 76% of pts and worst AVD was concordant between echo and SCor in 80% of pts. Concordance was defined as difference of 20 ms or less between the corresponding echo and SCor AV delay.
Conclusion-s: Assessment of cardiac function by SCor radial aa tonometry corresponds to various echo Doppler parameters of cardiac systolic and diastolic function. SCor may be used for Biv pacemaker programming after CRT.