. Author manuscript; available in PMC: 2013 Sep 1.

Published in final edited form as: J Child Neurol. 2012 Jun 29;27(9):1187–1192. doi: 10.1177/0883073812448461

Table 1.

Electrocardiogram Criteria in Pediatric Subjects

Electrocardiogram Feature	Criteria¹⁹
Right atrial enlargement	P wave >2.5 mV in leads II, III, or aVF
Left atrial enlargement	P wave >0.08 sec in leads II, III, or aVF
Right ventricular hypertrophy	R wave >95%ile in V₁, or S wave >95%ile in V₆, or rsR′ in V₁ and V₂ without QRS widening, or qR in V₁ and V₂
Left ventricular hypertrophy	S wave >95%ile normal in V₁, or R wave >95%ile in V₆
Bundle branch block	QRS >0.12 sec
Right axis deviation	>10 degrees
Left axis deviation	>−30 degrees
Intraventricular conduction delay	QRS >0.12 sec and without RBBB or LBBB pattern
Non-specific ST-T changes	ST-segment depression or elevation (leads I, aVL, V₄–V₆), flattening of the T wave (leads I, aVR, aVL, V₅, V₆), or T-wave inversion (I, V₂–V₄)
Strain	Down-sloping convex ST-segment depression (≥0.1 mV) with an inverted asymmetrical T-wave opposite to the QRS axis. In LVH w/strain these changes were seen in the left precordial leads, V₅ and/or V₆. In RVH w/strain these changes were seen in the right precordial leads, V₁–V₃.

Abbreviations: LBBB, left bundle branch block; LVH, left ventricular hypertrophy; RBBB, right bundle branch block; RVH, right ventricular hypertrophy.