In children with aortic stenosis, left ventricular strain on ECG indicates a worse prognosis and warrants left heart catheterization before considering valvotomy.
Aortic stenosis is a relatively common lesion in childhood. In severity, it may vary from extreme mildness to cases terminating in sudden death. The prognosis is worse in the presence of left ventricular strain as shown by the electrocardiogram. Progression of signs of left ventricular "strain" by electrocardiogram should be studied by catheterization of the left side of the heart prior to deciding upon aortic valvotomy.
Ongley et al. (Sat,) studied this question.