Monday, 9 June 2014

ECG & Echo Case Study: Right Heart Enlargement

88 year old male referred by the respiratory department for a routine outpatient echo ?heart failure. No history of angina.

From reading his ECG what do you think his echo is likely to show?

For those of you "in the know" this shouldn't be too difficult. If you are a beginner, however, take a good look at the polarity of the right precordial leads; a process of elimination in conjunction with the case history should lead you to the correct answer.

Thanks for reading and please feel free to use the ECG in your own presentations/CPD folder.
Will post the echo clips tomorrow...happy rhythms!

Answer: Say What You See

How many times have I heard this? It’s good advice though! Before trying to reach a diagnosis it’s a good idea write down any abnormal changes you see. Here is what I see:
  • Rhythm: irregular, no clear P waves, wavy baseline = Atrial Fibrillation (AF)
  • Polarity of V1: positive
  • ST changes: depression in V1-V4, and slight changes in the inferior leads

Positive V1

One of the things I always get new students to check is the polarity of V1. Under normal circumstances this should be predominantly negative. There are a handful of causes of a positive complex in V1, so as long as you know what these are, it’s possible (although not always) to reach a diagnosis by a process of elimination or at least narrow your list down somewhat. Of course, it always helps to place the ECG in some sort of clinical context as well.

The most common cause of a positive V1 is right bundle branch block. Following on from this and in no particular order other causes include: WPW syndrome type A, posterior myocardial infarction, hypertrophic cardiomyopathy, RVH/RV dilatation

We can rule out right bundle branch block and WPW here – there are no RSR complexes, the QRS is narrow, and there are no delta waves. The other causes are possible, but given the patient’s age, the fact that he’s pain free, and has been routinely referred from the respiratory department - it rather points to a right heart abnormality.

RVH/RV dilatation

Detecting RV enlargement on an ECG can be difficult. Echo is really the investigation of choice when determining this. However, ECG findings suggestive of RV enlargement can include all or some of the following:

  • Positive V1
  • Right Axis Deviation
  • Strain pattern (ST depression) in right precordial leads
  • Peaked P waves – A dilated RV is usually seen with a dilated RA.
Unfortunately the axis is not particularly helpful on this ECG, and we don’t have any P waves to give us extra clues. But, we do have a positive V1 and strain pattern (ST depression).  

Echo Findings

Significant right heart dilatation is when the right side becomes larger than the left. This is particularly evident here in the apical 4 chamber view. RV systolic function is poor and there is also flattening of the septum. Here is an annotated still clip to help you with the moving echo image.

During an echo we also measure tricuspid valve regurgitation and assess the inferior vena cava in order to estimate the PA pressure. Normal right sided pressures are around 35mmHg or less. In this study the PA pressures were significantly increased and estimated at around 80-85mmHg indicating severe pulmonary hypertension as a result of respiratory disease.

Thanks for reading, and as ever please feel free to comment or share - Mx

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