What are the echocardiography (echo) dimensions for classification of left ventricular hypertrophy (LVH)?

Echocardiographic Dimensions for Classification of Left Ventricular Hypertrophy

According to the European Association of Cardiovascular Imaging (EACVI) and American Society of Echocardiography (ASE) guidelines, left ventricular hypertrophy (LVH) is best classified using left ventricular mass (LVM) indexed to body surface area (BSA), with upper limits of normal being 95 g/m² for women and 115 g/m² for men. 1

Normal Values and Classification Thresholds

LV Mass Reference Values

• Linear Method (M-mode):

  • Women: 67-162 g (normal range); >162 g (LVH)
  • Men: 88-224 g (normal range); >224 g (LVH)

• LV Mass Indexed to BSA:

  • Women: 43-95 g/m² (normal range); >95 g/m² (LVH)
  • Men: 49-115 g/m² (normal range); >115 g/m² (LVH)

• 2D Method:

  • Women: 66-150 g (normal range); >150 g (LVH)
  • Men: 96-200 g (normal range); >200 g (LVH)

• 2D LV Mass Indexed to BSA:

  • Women: 44-88 g/m² (normal range); >88 g/m² (LVH)
  • Men: 50-102 g/m² (normal range); >102 g/m² (LVH)

Wall Thickness Measurements

• Septal Thickness:

  • Women: 0.6-0.9 cm (normal)
  • Men: 0.6-1.0 cm (normal)

• Posterior Wall Thickness:

  • Women: 0.6-0.9 cm (normal)
  • Men: 0.6-1.0 cm (normal)

Severity Classification of LVH

LVH Severity Based on Indexed LV Mass (g/m²)

• Women:

  • Mild: 96-108 g/m²
  • Moderate: 109-121 g/m²
  • Severe: ≥122 g/m²

• Men:

  • Mild: 116-131 g/m²
  • Moderate: 132-148 g/m²
  • Severe: ≥149 g/m²

Alternative Indexing Methods

• LV Mass/Height (g/m):

  • Women: Normal <100 g/m; Severe ≥129 g/m
  • Men: Normal <126 g/m; Severe ≥163 g/m

• LV Mass/Height²·⁷ (g/m²·⁷):

  • Women: Normal <44 g/m²·⁷; Severe ≥59 g/m²·⁷
  • Men: Normal <48 g/m²·⁷; Severe ≥64 g/m²·⁷

LV Geometry Classification

LV geometry is classified using both LV mass and relative wall thickness (RWT):

• Relative Wall Thickness (RWT) = (2 × posterior wall thickness) / LV internal diameter at end-diastole

  • Normal RWT: 0.22-0.42 (women); 0.24-0.42 (men)

• Four Geometric Patterns:

  1. Normal Geometry: Normal LV mass and normal RWT
  2. Concentric Remodeling: Normal LV mass with increased RWT (>0.42)
  3. Eccentric Hypertrophy: Increased LV mass with normal RWT (≤0.42)
  4. Concentric Hypertrophy: Increased LV mass with increased RWT (>0.42)

Clinical Implications and Pitfalls

1. Measurement Technique Matters:

   • Using septal thickness alone for LVH diagnosis is inadequate and has poor prognostic value compared to indexed LV mass 2
   • Up to 18.9% of patients without severely thickened septum may have severely abnormal indexed LV mass 2

2. Indexing Considerations:

   • BSA indexing is standard but may underestimate LVH in obese patients
   • Height-based indexing (especially height²·⁷) may be superior in overweight/obese patients 1

3. 3D Echocardiography Advantages:

   • More accurate for asymmetric or localized hypertrophy
   • Avoids geometric assumptions in abnormally shaped ventricles 1

4. Advanced Classification Systems:

   • Some researchers propose a 4-tiered classification based on LV concentricity and end-diastolic volume 3
   • This may better differentiate prognostic subgroups within traditional eccentric and concentric categories

5. Measurement Standardization:

   • Measurements should be taken at end-diastole
   • Use inner-edge-to-inner-edge method for linear dimensions
   • Position cursor perpendicular to the long axis of the ventricle

The ASE/EACVI guidelines strongly recommend using indexed LV mass rather than wall thickness alone for LVH diagnosis and severity assessment, as it provides superior prognostic information and more accurately reflects true LV hypertrophy 1.