LAUSR

OBJECTIVE To investigate the correlation between ventricular pre-excitation-related dyssynchrony, on cardiac dysfunction, and recovery. METHODS AND RESULTS This study included 76 children (39 boys and 37 girls) with a median age of 5.25 (2.67-10.75) years. The patients with pre-excitation-related cardiac dysfunction (cardiac dysfunction group, n = 34) had a longer standard deviation of the time-to-peak systolic strain of the left ventricle and larger difference between the maximum and minimum times-to-peak systolic strain than those with a normal cardiac function (normal function group, n = 42) (51.77 ± 24.70 ms versus 33.29 ± 9.48 ms, p < 0.05; 185.82 ± 92.51 ms versus 111.93 ± 34.27 ms, p < 0.05, respectively). The cardiac dysfunction group had a maximum time-to-peak systolic strain at the basal segments of the anterior and posterior septa and the normal function group at the basal segments of anterolateral and posterolateral walls. The prevalence of ventricular septal dyssynchrony in the cardiac dysfunction group was significantly higher than that in the normal function group (94.1% (32/34) versus 7.7% (3/42), p < 0.05). The patients with ventricular septal dyssynchrony (n = 35) had a significantly higher prevalence of intra-left ventricular systolic dyssynchrony than those with ventricular septal synchrony (n = 41) (57.1% (20/35) versus 14.6% (6/41), p < 0.05). During follow-up after pathway ablation, the patients who recovered from intra-left ventricular dyssynchrony (n = 29) had a shorter left ventricular ejection fraction recovery time than those who did not (n = 5) (χ2 = 5.94, p < 0.05). Among the patients who recovered, 93.1% (27/29) had a normalised standard deviation of the time-to-peak systolic strain and difference between the maximum and minimum times-to-peak systolic strain within 1 month after ablation. CONCLUSION Ventricular pre-excitation may cause ventricular septal dyssynchrony; thus, attention must be paid to intra-left ventricular dyssynchrony and cardiac dysfunction. Whether intra-left ventricular systolic dyssynchrony can resolve within 1 month may be a new early predictor of patient prognosis.