Is This Wenckebach?

I was asked for an opinion on this ECG.

There is sequential shortening of the PR interval and no dropped beats.This is not AV dissociation or isorhythmic AV dissociation as the R to R intervals are different and related to the PR intervals.This is reversed Wenckebach and below is another example.

Reversed Wenckebach is a rare ECG finding where there is sequential shortening of the PR interval and when it reaches its shortest value, the sequence is repeated often without a dropped beat.When a dropped beat occurs, there may be syncope and a permanent pacemaker required.In the good old days this was an arrhythmia associated with digitalis toxicity.Dr Harry Mond