643 Is there a Relationship Between the T Peak to End Interval and Right Bundle Branch Block?

Background: The interval between the peak and end of the T wave (TpTe) is an index of spatial dispersion in transmural cardiac repolarization We set out to examine the behaviour of TpTe in the presence of right bundle branch block (RBBB) as a potential marker for arrhythmogenesis. Methods: 42 children with RBBB were enrolled. In 39 RBBB occurred post cardiac surgery, in 3 secondary following cardiomyopathy From a resting 12-lead digital ECG, TpTe, RR, QT, and JT intervals were measured (leads II and V5) Bazett and Fridericia formulas were applied to TpTe for heart rate correction and TpTe/QT and TpTe/JT were calculated Results were compared to normal data (400 children) Descriptive and analytical statistics significance level set at p< 005. Results: Median age 7,7 years ± 5,9 Mean QRS duration 120ms (range 88-168 ms) TpTe lead II 93 ms ± 15, V5 95 ms + 14, lead II TpTeB 118 ± 23, TpTeF 109 + 19, V5 TpTeB 120 ± 20; TpTeF 111 + 17 TpTe/JT II 0,42 + 0,1 and 0,42 + 0,1, TpTe/ QT II 0,27 + 004 and TpTe/QT V5 0,27 + 0,04 All the values measured were significantly different p