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Background: PW Doppler has been used to assess inter-ventricular dyssynchrony in cardiac resynchronization therapy (CRT) candidates by measuring the inter-ventricular mechanical delay (IVMD), defined as the time difference between the LV and RV pre-ejection periods. These measurements lack the possibility of simultaneous recording and, therefore, carry a burden of high inter-measurement variability and dependence on cardiac workload. The aim of the study was to evaluate whether Color Doppler Myocardial Imaging (CDMI) velocity data derived from the aortic (AV) and pulmonic valve (PV) cusps motion can be used for IVMD quantification from a single cardiac cycle.Methods: 15 healthy individuals (34.1±10.1 years) and 50 CRT patients (62.2±11.1 years) underwent standard echocardiographic examination extended with CDMI data acquisition. PW Doppler was used to determine pre-ejection periods (the interval from the beginning of the QRS complex to the beginning of the LV/RVOT flow). Data was averaged from 3 consecutive cardiac cycles before IVMD was calculated. CDMI was performed from the parasternal short axis aortic view followed by extraction of velocity traces from a single cycle velocity data-set of both AV and PV cusps motion, in which valve openings are represented by distinct spikes. IVMD was calculated as the interval between the AV and PV opening (inter-valvular opening delay). Pearson correlation analysis was applied to evaluate findings.Results: A strong correlation between PW Doppler and CDMI derived IVMD was found (r=0.92, p<0.001), somewhat more pronounced among healthy individuals (r=0.971 vs r=0.886).Conclusions: CDMI of the AV and PV cusps motion is a novel, non-time consuming method in the evaluation of inter-ventricular dyssynchrony. The potential advantages have yet to be evaluated.