How do you differentiate between concentric and eccentric left ventricular hypertrophy (LVH) on echocardiography (echo)?

Differentiating Concentric and Eccentric LVH on Echocardiography

The primary distinction between concentric and eccentric left ventricular hypertrophy (LVH) on echocardiography is based on relative wall thickness (RWT), with concentric LVH having RWT ≥0.42 and eccentric LVH having RWT ≤0.42, both with increased LV mass. 1

Key Diagnostic Parameters

Relative Wall Thickness (RWT)

• Formula: RWT = (2 × posterior wall thickness) / LV internal diameter at end-diastole 1
• Cutoff value: 0.42 1
  • RWT ≥0.42 = concentric pattern
  • RWT ≤0.42 = eccentric pattern

LV Mass Index (LVMI)

• Normal values:
  • Men: ≤115 g/m² (linear method) or ≤102 g/m² (2D method)
  • Women: ≤95 g/m² (linear method) or ≤88 g/m² (2D method) 1
• LVH is defined as LVMI exceeding these values

Geometric Patterns Classification

1. Normal LV: Normal LVMI and normal RWT (0.32-0.42)
2. Concentric Remodeling: Normal LVMI with increased RWT (>0.42)
3. Concentric LVH: Increased LVMI with increased RWT (>0.42)
4. Eccentric LVH: Increased LVMI with normal RWT (≤0.42) 1

Visual Characteristics

Concentric LVH

• Uniformly increased wall thickness around the LV 2
• Normal LV cavity size 2
• Thickened walls with preserved cavity dimensions 1
• Example measurements: LVDd 48 mm; LVDs 34 mm; IVS 18 mm; PW 15 mm 1

Eccentric LVH

• Increased LV cavity dimensions 1
• Proportional increase in wall thickness
• Example measurements: LVDd 56 mm; LVDs 39 mm; IVS 12 mm; PW 12 mm 1

Advanced Classification

The European Association of Cardiovascular Imaging (EACVI) and American Society of Echocardiography (ASE) recommend a more detailed 8-category classification based on:

• LV mass (normal vs. increased)
• LV volume (normal vs. increased)
• RWT (normal vs. increased) 1

This expanded classification includes:

1. Normal ventricle
2. Physiological hypertrophy
3. Concentric remodeling
4. Eccentric remodeling
5. Concentric hypertrophy
6. Mixed hypertrophy
7. Dilated hypertrophy
8. Eccentric hypertrophy 1

Clinical Implications

• Concentric LVH is typically associated with pressure overload (e.g., hypertension, aortic stenosis) 2
• Eccentric LVH is typically associated with volume overload (e.g., valvular regurgitation) 1
• Patients with concentric LVH have more severe LV diastolic dysfunction than those with eccentric LVH, even with similar LVMI values 3
• Concentric LVH carries higher risk for adverse cardiovascular outcomes compared to eccentric nondilated LVH 4

Common Pitfalls

1. Measurement errors: Ensure proper alignment of M-mode cursor perpendicular to the LV long axis
2. Asymmetric hypertrophy: In patients with asymmetric septal hypertrophy, linear measurements may overestimate LV mass 1
3. Borderline cases: Values close to cutoffs should be interpreted with caution
4. Obesity effects: Consider indexing LV mass to height^2.7 in overweight/obese patients 1
5. Misclassification: Failure to account for LV volume can lead to misclassification of LVH patterns 4

Measurement Techniques

• M-mode: Traditional method, but limited by geometric assumptions
• 2D echocardiography: More accurate than M-mode, especially for abnormally shaped ventricles
• 3D echocardiography: Most accurate for LV mass measurement, especially in asymmetric hypertrophy 1

For the most accurate assessment, particularly in patients with abnormal LV geometry, 3D echocardiography should be considered as it measures myocardial volume directly without geometric assumptions 1.