Ashman phenomenon of the T wave

In 1947 Gouaux and Ashman 1 described a patient with atrial fibrillation in whom the sequence of long-short cycle lengths led to QRS aberration of the QRS complex terminating the short cycle. The long cycle causes the action potential 2 and refractory period 3–5 of the next beat to lengthen. The impulse that terminates the short cycle is thus likely to meet relatively refractory ventricular conduction tissue. 6 Such QRS aberration has been referred to as the Ashman phenomenon. Because the form of the T wave is influenced by both the ventricular repolarization process and the ventricular activation sequence, aberrated QRS complexes of the Ashman phenomenon are usually accompanied by T-wave abnormalities. We report here 2 patients in whom T-wave aberration occurred in the absence of QRS aberration, when short ventricular cycles followed beats of relatively longer cycles. This is the first description of the Ashman phenomenon of the T wave without aberration of the corresponding QRS complex.