How do you diagnose left ventricular hypertrophy (LVH) on a 12-lead electrocardiogram (EKG)?

Diagnosing Left Ventricular Hypertrophy on a 12-Lead ECG

The most accurate approach to diagnosing left ventricular hypertrophy (LVH) on a 12-lead ECG is to use validated voltage criteria, particularly the Sokolow-Lyon criterion (S wave in V1 + R wave in V5 or V6 > 35 mm) or the Cornell voltage criterion (S wave in V3 + R wave in aVL > 28 mm for men and > 20 mm for women), both with high specificity of 85-90%. 1

Primary Voltage-Based Criteria

• Sokolow-Lyon criterion: Sum of S wave in V1 and R wave in V5 or V6 > 35 mm 1
• Cornell voltage criterion: Sum of S wave in V3 and R wave in aVL > 28 mm for men and > 20 mm for women 1
• Cornell voltage-duration product: Cornell voltage × QRS duration > 2440 mm·ms 1
• Romhilt-Estes point score system: Incorporates QRS amplitude, ST-T abnormalities, left axis deviation, QRS duration, and intrinsicoid deflection 1

Supporting ECG Findings

• ST-T wave abnormalities strongly support the diagnosis of LVH and are associated with larger left ventricular mass and higher cardiovascular risk 2, 1
• Left atrial abnormalities, such as P-wave changes suggesting left atrial enlargement, can be an early sign of hypertensive heart disease 2, 1
• Left axis deviation may support the diagnosis of LVH but should not be used alone 2, 1
• QRS duration prolongation often accompanies LVH and can support the diagnosis 2, 1

Special Considerations

LVH Diagnosis with Left Bundle Branch Block (LBBB)

• Diagnosis of LVH in the presence of LBBB is challenging and should be made with caution 2
• Some studies suggest using SV2 + RV6 > 4.5 mV as a diagnostic criterion for LVH in the presence of LBBB 3
• QRS duration > 160 ms plus left atrial enlargement strongly supports the diagnosis of LVH in LBBB 3

LVH Diagnosis with Right Bundle Branch Block (RBBB)

• In patients with RBBB, the sensitivity of voltage criteria is decreased 1
• Criteria such as SV1 > 2 mm, RV5/V6 > 15 mm, and QRS axis left of -30° can support the diagnosis 1

Factors Affecting ECG Diagnosis of LVH

• Age: QRS voltages decline with increasing age, and standard criteria best apply to adults over 35 years 1
• Gender: Women have slightly lower upper limits of QRS voltage than men 1
• Body habitus: Obesity can increase left ventricular mass but decrease QRS voltage due to increased distance between the heart and recording electrodes 1
• Race: Criteria should be adjusted for race when such criteria have been validated 2

Advanced Approaches

• Time-voltage area measurements of QRS complexes can significantly improve sensitivity for LVH detection compared to simple voltage criteria or voltage-duration products 4
• The 12-lead sum area and Sokolow-Lyon area showed 76% and 65% sensitivity respectively, significantly greater than the sensitivity of voltage-duration products (54%) and simple voltage criteria (46% and 43%) 4
• Two-lead QRS area sum from specific locations in the upper and lower right precordium has shown 90% sensitivity with 100% specificity for LVH detection 5

Important Recommendations

• Interpretation of ECGs for LVH should use only validated criteria, without deviation from the validated formulas 2
• No single diagnostic criterion can be recommended for use compared with others 2
• Computer systems should use all criteria that are supported by valid evidence for identifying LVH 2
• Interpretations should specify which diagnostic criteria were used and which were abnormal 2
• The terms "strain," "systolic," and "diastolic" should not be used in diagnostic statements related to LVH 2
• The terms "probable," "possible," and "borderline" should be used with caution 2

By systematically applying these criteria and considering the supporting findings and special circumstances, clinicians can accurately diagnose LVH on a 12-lead ECG, which is crucial for risk stratification and management of patients with cardiovascular disease.