11. Cardiac Resynchronization Therapy: Different Issues: 11.5 Automatic Border Detection Pattern of Left Ventricle for Biventricular Pacing

to assess if the pattern of left ventricle (LV) volume curves variation using automatic border detection (ABD) can help in differentiation of desynchronized contraction.

patients (pts) with dilated cardiomyopathy were included (n = 41; 58.3±16.2 years). Currently accepted TDI and TM parameters were used to indicate LV desynchronization. On-line continuous LV volumes changing were recorded using ABD. Ejection time (ET ABD) was measured from ABD wave-forms as time interval between maximal and minimal volume variation during LV electromechanical systole. Ejection time index was derived as ratio ET ABD/RR interval (ETi ABD = ET/RR).

26 pts presented QRSd>120ms, 15 pts had QRSd<120 ms. Ventricular desynchronization was found in 31 pts (23 pts QRSd>120ms, 8 pts QRSd<120ms). In these pts ET ABD was 232±42ms significantly smaller than in pts without asynchrony (323±27 ms, p=0.0001); difference in ETi ABD was: 27±8% vs 39.5±4%, p=0.0001; 12 pts undergone biventricular pacing and presented significant improvement in ETi ABD (26±4% vs 31±5%, p=0.001) and LV volume contraction pattern.

ABD can help in differentiation of ventricular asynchrony and may be used in the follow-up of multisite pacing.