But what about the T waves ?

The most striking thing to my eye regarding the second ECG is the relative depth of the T-waves. They look deeper than one would expect from the RBBB alone.

There is a very broad range of potential causes of such T-wave changes including ischaemia, cardiomyopathy, myocarditis, raised ICP, PE and hyperventilation.

There is also another cause of T-wave change that is very likely in this case which is ‘Cardiac T-wave memory’ this occurs after a period of abnormal ventricular depolarisation e.g. paced rhythm, VT, SVT with aberrancy and preexcitation. 

Vakil et al provide a nice overview of T-wave memory, proposed mechanisms, and a case example.

The deep T wave inversion on this ECG correspond to the leads in which a negative QRS was seen in the patients pre-excited ECG. Patient’s often require work-up to exclude underlying ischaemia or structural disease but cardiac T-wave memory is a benign and self-resolving condition in itself.

What happened ?

Well our patient had a negative troponin and D-dimer with a normal chest x-ray. Her pain was felt to be benign in origin. She was reviewed by cardiology in light of her pre-excitation and out-patient follow-up arranged.