From the Guidelines
Large R waves and S waves on an ECG typically indicate ventricular hypertrophy, which is an enlargement or thickening of the heart's ventricles, and the pattern of these waves can help differentiate between left and right ventricular hypertrophy. The presence of tall R waves in the left-sided leads (I, aVL, V5-V6) and deep S waves in the right-sided leads (V1-V2) is characteristic of left ventricular hypertrophy (LVH), while right ventricular hypertrophy (RVH) shows the opposite pattern with tall R waves in right-sided leads and deep S waves in left-sided leads 1. These findings occur because the enlarged ventricular muscle mass generates stronger electrical forces during depolarization, resulting in higher voltage deflections on the ECG. Some key points to consider when interpreting ECGs for ventricular hypertrophy include:
- The presence of combined tall R waves and deep S waves in leads V2 to V6, with combined amplitude greater than 60 mm (6.04 mV), suggests the presence of LVH in patients with congenital heart defects and RVH 1.
- In patients with ECG criteria for LVH, the presence of prominent S waves in V5 or V6, right axis deviation, unusually tall biphasic R/S complexes in several leads, and signs of right atrial abnormality are useful signs that RVH may also be present 1.
- The sensitivity of ECG criteria for RVH is generally low, but some criteria have high specificity and can be used to advantage in diagnostic schemes or to derive continuous variables 1.
- The use of ancillary clinical information plays a greater role in the appropriate use of the ECG for the purpose of recognizing RVH than it does in the case of LVH or the atrial abnormalities 1. When identified on ECG, further evaluation with echocardiography is typically warranted to confirm the diagnosis and determine the underlying cause, as ventricular hypertrophy can be associated with increased cardiovascular risk and may require treatment of the underlying condition.
From the Research
ECG Interpretation
- Large R waves and S waves on an electrocardiogram (ECG) can indicate left ventricular hypertrophy (LVH) 2, 3, 4, 5, 6
- The presence of large R waves and S waves can be associated with an increased left ventricular mass, which is a characteristic of LVH 4, 5, 6
- However, the correlation between ECG findings and left ventricular mass is not always strong, and other factors such as myocardial fibrosis can affect ECG parameters 3, 4, 6
Diagnostic Criteria
- Various ECG voltage criteria have been proposed for the diagnosis of LVH, including the Sokolow-Lyon, Romhilt-Estes, and Cornell criteria 3, 4, 5, 6
- The Romhilt-Estes score has been shown to be the most sensitive ECG criterion for detecting LVH in patients with hypertrophic cardiomyopathy 4
- However, the performance of ECG voltage criteria can vary depending on the population being studied and the specific criteria used 5
Relationship with Cardiac Imaging
- ECG findings can be correlated with cardiac imaging modalities such as echocardiography and cardiac magnetic resonance imaging (CMR) 3, 4, 6
- CMR can provide additional information on myocardial tissue characteristics, such as fibrosis, edema, and inflammation, which can affect ECG parameters 6
- The combination of ECG and CMR can provide a more comprehensive understanding of left ventricular hypertrophy and its underlying pathophysiology 6