What does the above Holter demonstrate?
Why is the PR interval prolonged for some of the sinus beats?
What does this Holter demonstrate?
Interpolated PVCs – these are ventricular ectopics that occur between two sinus beats without a pause.
A phenomenon called concealed conduction where the PVCs penetrate retrogradely to the AV node – it is concealed because the only evidence that this has occurred is ‘indirect’ – ie. PR interval prolongation in the subsequent sinus beats (*).