Common mistakes - Left Ventricular Hypertrophy

While left ventricular hypertrophy is a common finding, its assessment can be quite difficult. I certainly had my learning’s here. Lets start with the 5 most important things you should NOT do when you are looking at the thickness of the myocardium:

1) Don´t use MMode to assess LVH

That’s what I did when I started with echocardiography. Off course back then this is what the guidelines recommended. But in the meantime we know that the M-Mode line rarely cuts the ventricle perpendicular. This means you will often overestimate the thickness of the myocardium. 2D Echo is what you should use. MMode has many limitations when it comes to measuring the septum. It is often very difficult to transect the septum perpendicular.

My Tip: Perform several 2D measurements both from a parasternal (long and short) and apical view (angulated 4-chamber view)

2) The moderator band is included into the measurement

Both the moderator band and RV trabecula can lie adjacent to the interventricular septum. Sometimes it is difficult to delineate them from the septum. But including them into your measurement can lead to significant overestimation of septal thickness. Short axis view showing the moderator band (1), the measurement should exclude this structure (2)

My Tip: angulate the transducer until you get a view where you can clearly delineate the moderator band from the septum. Use this view for your measurement.

2) Measuring the thickest part of the septum

We all know the thickness of the septum varies and quite frequently you will see a buldge in the proximal portion. Measuring septal thickness there is not representative of the entire ventricle Example of a patient with hypertrophy and a septal buldge (B) measuring 18mm. The septum measures 14mm distal (A), and 12 mm proximal (C) from the buldge.

My Tip: : Describe the shape of the septum and provide detailed information on where you measure. Summarize you impression (hypertrophy yes or no and how severe) based on all measurements. Alternatively you can also calculate the LV mass.

3) The findings are not put into a clinical context

A millimeter up or down can make a huge difference for the patient. Is he healthy or not? Is hypertrophy present? And you don’t want to make someone sick just based on the tiny motion of the trackball when you perform the measurement. While we have cut off values, be aware that the thickeness of the septum will be different in someone who has a body surface area of over 2.3m2, opposed to someone who is small. Clearly it is also important to know if someone has hypertension or not. 32 year old male with a septal thickness of 12mm. But, this patient does not have a pathologic form of hypertrophy. He is athletic and has a BSA of 2.4 m. The left atrium is normal in size, no valvular pathology or diastolic dysfunction is present, The patient also has no history of hypertension.

My Tip: Talk to the patient, find out more about him. Is he hypertensive? Does he do lots of sports?

4) Not actively looking for apical hypertrophy

Apical hypertrophic cardiomyopathy can easily be missed, especially when you are foreshortening the left ventricle, your gain settings are set low or the image quality is poor. Sure you can use contrast, but first you have to have the suspicion. 2: would you suspect apical HCMP in this patient? 1: The contrast study clearly demonstrates at least moderate hypertrophy at the apex.

My Tip: Make sure you always see the endocardial and epicardial boarder of the myocardium at the apex. Only then will you be able to see how thick the apical myocardium is. Use atypical apical views and a 2-chamber view to avoid foreshortening

5) Not using strain to assess hypertrophy

2D echo allows us to detect and measure the thickness on the myocardium. But a thick myocardium can mean many things. Does the patient have hypertrophic cardiomyopathy? Is it true hypertrophy what makes the septum thick or does the patient have a storage disease? This is where speckle tracking echocardiography comes into play. It provided information on the contractility of the myocardium and the strain pattern can help in the differential diagnosis of LVH Strain pattern in a hypertensive patient with severe left ventricular hypertrophy. Global longitudinal strain is reduced (-13.5%) despite normal ejection fraction (59%). Note that the basal segments are more prominently reduced that the apcial segments.

My Tip: Embark on the journey to learn speckle tracking echocardiography and use it in patients with LVH

Certainly there are many more teaching points to talk about when it comes to left ventricular hypertrophy. Let us know if there are any important topics you want us to cover!

For those of you who want to dig deeper we have much more teaching content:
https://www.123sonography.com/out-of-the-storm

Best Thomas Binder and the 123sonography team Thomas Binder