What is the criteria for grading left ventricular (LV) hypertrophy via echocardiogram?

From the Guidelines

Left ventricular hypertrophy (LVH) is diagnosed on echocardiogram when the maximal end-diastolic wall thickness is ≥15 mm anywhere in the left ventricle in adults, in the absence of another cause of hypertrophy, as stated in the 2020 AHA/ACC guideline 1. The criteria for grading LVH via echocardiogram are based on the maximal end-diastolic wall thickness, with a threshold of ≥15 mm used for adults.

• For children, the diagnostic criteria are adjusted for body size and growth, using a body surface area-adjusted z-score of ≥2 standard deviations above the mean, with a proposed threshold of z >2.5 for asymptomatic children with no family history and z >2 for children with a definitive family history or positive genetic test 1.
• The pattern and distribution of LV wall thickening can vary, with the basal anterior septum being the most common location for LVH, and hypertrophy can be limited and focal, confined to only 1 or 2 LV segments with normal LV mass 1.
• The assessment of LVH should focus on measuring the interventricular septum and posterior wall thickness during diastole, and LVH can also be quantified using left ventricular mass calculations, although specific values are not provided in the 2020 AHA/ACC guideline 1.
• Accurate diagnosis and grading of LVH are crucial for guiding management decisions, including blood pressure control, valve intervention, or specific cardiomyopathy treatments, and for assessing cardiovascular risk 1.

From the Research

Criteria for Grading Left Ventricular Hypertrophy

The criteria for grading left ventricular (LV) hypertrophy via echocardiogram involve assessing several cardiac parameters, including:

• Wall thickness
• Left ventricular mass (LVM)
• LV geometry 2
• Relative wall thickness (RWT) 3
• LV volume 3

Assessment of LVH Severity

The severity of LVH is typically assessed using echocardiography, which is the most validated and widely used non-invasive approach 3. The assessment of LVH severity is crucial for prognosis and treatment choices, as LVH severity grades correlate with the risk of presenting cardiovascular events 2.

Classification of LVH

There are different classifications of LVH, including:

• A 2-group classification based on LV mass and RWT 3
• A 4-group subdivision based on LV mass, LV volume, and RWT, which provides distinct differences in cardiac function and allows clinicians to distinguish between different LV hemodynamic stress adaptations in various cardiovascular diseases 3

Comparison of Imaging Modalities

Different imaging modalities, including echocardiography, cardiac magnetic resonance (CMR), and computed tomography (CT), can be used to assess LVH severity. However, there is no extensive data to support reference values based on CMR and CT, and comparative studies between the three techniques show different results in wall thickness and LVM measurements 2, 4. Contrast echocardiography has been shown to more closely approximate CMR measurements of wall thickness 4.