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Assoc Prof Harry Mond
February 23, 2026
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The techs this week showed me an atrial tachyarrhythmia which did not conduct to the ventricle. The rate was about 300 bpm and was slightly irregular. The pattern was repeated many many times.
Those, who report lots of Holters, see this about once a month and this is a focal atrial tachycardia with block, although the third beat probably conducts. This is rarely reported in the literature.In the next example from the same patient, there is again one conducted beat. The focal atrial tachycardia is irregular and the last atrial complex occurs earlier and then blocks. The ladder diagram, demonstrates that this is a “Wenckebach block at the ectopic-myocardial junction”.There is also a suggestion of Wenckebach AV block as well.
I reported this recently in Heart Lung and Circulation. The examples are below and a reprint enclosed.
Assoc Prof Harry Mond
October 16, 2026
Retrograde conduction is defined as conduction from an ectopic site to the atrium via the AV node or accessory pathway and referred to as VA conduction. II results in a P wave configuration which differs from an anterograde P wave, and in most ECG leads is inverted. The site from where the impulse originates can be the AV node, Bundle of His, distal conducting system or the body of the ventricles including ventricular pacing. On the ECG, the QRS complex usually precedes the inverted retrograde P wave but on occasion may follow it.
October 1, 2026
In 1970, I commenced work as a “novice” cardiologist at The Royal Melbourne Hospital. Training at that time was learning how to recognise the diastolic murmur of mitral stenosis and making sure the ECG and chest x-rays were the correct way up. As this was prior to coronary artery surgery, stenting and echocardiography, the ECG was a highly respected tool for the diagnosis of many conditions. I was fortunate to befriend a number of the gurus of ECG interpretation who taught me to look into the soul of an ECG. Today, even though the ECG is the first investigation performed by a cardiologist, the art of ECG interpretation has been lost because we depend on the new tools for cardiac diagnosis.
September 18, 2026
Dr Thura Thant asked for an opinion on this confusing ECG. By using arrows and highlight, the ECG bared its soul and gave me an answer. See if you can work it out? What do you think?
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