Left Ventricular Hypertrophy (LVH)

ECG Diagnostic criteria

Voltage Criteria

Limb Leads

• R wave in lead I + S wave in lead III > 25 mm
• R wave in aVL > 11 mm
• R wave in aVF > 20 mm
• S wave in aVR > 14 mm

Precordial Leads

• R wave in V4, V5 or V6  > 26 mm
• R wave in V5 or V6 plus S wave in V1 > 35 mm
• Largest R wave plus largest S wave in precordial leads > 45 mm

Non Voltage Criteria

• Increased R wave peak time > 50 ms in leads V5 or V6
• ST segment depression and T wave inversion in the left-sided leads: AKA the left ventricular ‘strain’ pattern

Pathophysiology

• The left ventricle hypertrophies in response to pressure overload secondary to conditions such as aortic stenosis and hypertension
• This results in increased R wave amplitude in the left-sided ECG leads (I, aVL and V4-6) and increased S wave depth in the right-sided leads (III, aVR, V1-3)
• The thickened LV wall leads to prolonged depolarisation (increased R wave peak time) and delayed repolarisation (ST and T-wave abnormalities) in the lateral leads

Additional ECG changes seen in LVH

• Left atrial enlargement
• Left axis deviation
• ST elevation in the right precordial leads V1-3 (“discordant” to the deep S waves)
• Prominent U waves (proportional to increased QRS amplitude)

Causes of LVH

• Hypertension (most common cause)
• Aortic stenosis
• Aortic regurgitation
• Mitral regurgitation
• Coarctation of the aorta
• Hypertrophic cardiomyopathy

Handy Tips

• Voltage criteria alone are not diagnostic of LVH
• ECG changes are an insensitive means of detecting LVH (patients with clinically significant left ventricular hypertrophy seen on echocardiography may still have a relatively normal ECG)

ECG Examples

Example 1

Left ventricular hypertrophy (LVH):

• Markedly increased LV voltages: huge precordial R and S waves that overlap with the adjacent leads (SV2 + RV6 >> 35 mm).
• R-wave peak time > 50 ms in V5-6 with associated QRS broadening.
• LV strain pattern with ST depression and T-wave inversions in I, aVL and V5-6.
• ST elevation in V1-3.
• Prominent U waves in V1-3.
• Left axis deviation.

Severe LVH such as this appears almost identical to left bundle branch block — the main clue to the presence of LVH is the excessively high LV voltages. 

Example 2

• There are massively increased QRS voltages — the S waves in V3 are so deep they are literally falling off the page!
• The ST elevation in V1-3 is simply in proportion to the very deep S waves (“appropriate discordance”).
• The LV strain pattern is seen in all leads with a positive R wave (V5-6, I, II, III, aVF).

Related Topics

• Right ventricular hypertrophy
• Left atrial enlargement
• Left bundle branch block

References

• Edhouse J, Thakur RK, Khalil JM. ABC of clinical electrocardiography. Conditions affecting the left side of the heart. BMJ. 2002 May 25;324(7348):1264-7

Advanced Reading

Online

• Wiesbauer F, Kühn P. ECG Mastery: Yellow Belt online course. Understand ECG basics. Medmastery
• Wiesbauer F, Kühn P. ECG Mastery: Blue Belt online course: Become an ECG expert. Medmastery
• Kühn P, Houghton A. ECG Mastery: Black Belt Workshop. Advanced ECG interpretation. Medmastery
• Rawshani A. Clinical ECG Interpretation ECG Waves
• Smith SW. Dr Smith’s ECG blog.

Textbooks

• Zimmerman FH. ECG Core Curriculum. 2023
• Mattu A, Berberian J, Brady WJ. Emergency ECGs: Case-Based Review and Interpretations, 2022
• Straus DG, Schocken DD. Marriott’s Practical Electrocardiography 13e, 2021
• Brady WJ, Lipinski MJ et al. Electrocardiogram in Clinical Medicine. 1e, 2020
• Mattu A, Tabas JA, Brady WJ. Electrocardiography in Emergency, Acute, and Critical Care. 2e, 2019
• Hampton J, Adlam D. The ECG Made Practical 7e, 2019
• Kühn P, Lang C, Wiesbauer F. ECG Mastery: The Simplest Way to Learn the ECG. 2015
• Grauer K. ECG Pocket Brain (Expanded) 6e, 2014
• Surawicz B, Knilans T. Chou’s Electrocardiography in Clinical Practice: Adult and Pediatric 6e, 2008
• Chan TC. ECG in Emergency Medicine and Acute Care 1e, 2004

LITFL Further Reading

• ECG Library Basics – Waves, Intervals, Segments and Clinical Interpretation
• ECG A to Z by diagnosis – ECG interpretation in clinical context
• ECG Exigency and Cardiovascular Curveball – ECG Clinical Cases
• 100 ECG Quiz – Self-assessment tool for examination practice
• ECG Reference SITES and BOOKS – the best of the rest