Handed this ECG, our Medical Director Assoc Prof Harry Mond was asked if it was an example of a rate adaptive pacing, which uses changes in transthoracic impedance to increase the pacemaker rate in response to physiologic demand. It was not a paced rhythm, however, these pacing algorithms create regular artefact on the ECG tracing, whether they are pacing or not in the ventricle. Using examples, we look at the technology and the defining characteristics that identify the correct results for each.

Sinus arrhythmia is unusual in a 63-yr-old but we were asked to amend a ‘normal’ result to reflect this diagnosis. With classical examples of the pattern in under 30s and showing how NOT to confuse it with atrial ectopy, Assoc Prod Harry Mond shows how to uncover the correct result.

The presentation of pseudo Wolff-Parkinson-White Syndrome recently had an international customer return a report with a note pointing out that we had missed the diagnosis of intermittent pre-excitation - the Wolff-Parkinson-White Syndrome. But as Assoc Prof Harry Mond explains in this latest cardiac case study, it is not what it seems. He reveals where the confusion lies, and how to come to the correct diagnosis.

Showing a number of 2.8 second nocturnal pauses and bundle branch block, this latest case begs the question: is this high degree AV block and does the patient need a pacemaker? Using 11 difference traces, Assoc Prof Harry Mond delves into the topic of Wenckebach and Non-conducted Atrial Ectopics, reminding us of the differences between termination and extension, and that atrial and ventricular ectopics terminate a Wenckebach sequence differently!

This ECG was reported as complete heart block, and at first glance it sure looks like it. But a closer examination revealed the ventricular response was irregular. In this latest case study Assoc Prof Harry Mond explains two P wave patterns that reveal the rhythm as an alternating Wenckebach AV block, along with the characteristics of the rhythm and how to make sense of them.

Reported as dual chamber pacing, this case study needed closer examination. With obvious atrial pacing, the question of ventricular pacing remained. Assoc Prof Harry Mond details the characteristics that reveal the correct diagnosis, and why this should not be confused with pacemaker malfunction.

Atrial flutter or supraventricular tachycardia with block can often give the appearance of a bidirectional tachycardia, which can be caused by many other things. In this latest case study, our Medical Director Assoc Prof Harry Mond explains how to identify the characteristics of a tachycardia by using a series of ECG tracings, as well as explaining how he reached the correct conclusion when asked whether an ECG was showing a ventricular tachycardia.

Overnight Wenckebach AV block is a common finding in young people and is usually found in the presence of sinus bradycardia/sinus slowing. In this latest edition in our clinical case studies series, we look at how to identify atypical Wenckebach AV block, and how it’s affected by timing.

Reversed Wenckebach occurs when there is sequential shortening of the PR interval, and can require a permanent pacemaker in certain instances. In this latest case study, we take a look at examples of reversed Wenckebach, and how to recognise the rare ECG finding.