What are the electrocardiogram (EKG) findings in ventricular hypertrophy?

From the Guidelines

Ventricular hypertrophy on EKG is characterized by specific voltage criteria and secondary repolarization abnormalities, with left ventricular hypertrophy (LVH) typically showing increased QRS voltage in left-sided leads and right ventricular hypertrophy (RVH) presenting with right axis deviation and tall R waves in right precordial leads. The diagnosis of ventricular hypertrophy on EKG is based on measurements of QRS voltages, with various criteria having been proposed over the years, including the Sokolow-Lyon criterion and the Cornell voltage criterion 1. These criteria have been correlated with autopsy data, clinical and hemodynamic identification of conditions that impose increased workloads on the ventricles, and echocardiography 1.

Some key EKG findings for LVH include:

• Increased QRS voltage in left-sided leads, with R waves in leads I, aVL, V5, and V6 exceeding normal limits
• Deep S waves in right precordial leads
• Common voltage criteria include S in V1 + R in V5 or V6 > 35 mm, R in aVL > 11 mm, or R in I + S in III > 25 mm
• Secondary ST-T changes often appear as "strain pattern" with ST depression and T wave inversion in leads with tall R waves

For RVH, key EKG findings include:

• Right axis deviation
• Tall R waves in right precordial leads (R:S ratio > 1 in V1)
• Deep S waves in left precordial leads
• Sometimes right bundle branch block pattern
• T wave inversions in right precordial leads

It's essential to note that the sensitivity of EKG criteria for ventricular hypertrophy is generally low, and echocardiography remains the gold standard for confirming ventricular hypertrophy 1. Additionally, the ECG lacks sufficient sensitivity to serve as a screening tool for the detection of significant pulmonary arterial hypertension (PAH), although certain features of the ECG in patients with an established diagnosis of PAH may have prognostic value 1.

In clinical practice, it's crucial to consider the patient's overall clinical presentation, medical history, and other diagnostic test results when interpreting EKG findings for ventricular hypertrophy. The use of ancillary clinical information plays a significant role in the appropriate use of the ECG for recognizing ventricular hypertrophy.

From the Research

EKG Findings for Ventricular Hypertrophy

• The ECG diagnosis of left ventricular hypertrophy (LVH) is predominantly based on the QRS voltage criteria, which includes the increased QRS complex amplitude in defined leads 2.
• The classical ECG diagnostic paradigm postulates that the increased left ventricular mass generates a stronger electrical field, increasing the leftward and posterior QRS forces, reflected in the augmented QRS amplitude in the corresponding leads 2.
• However, clinical observations document increased QRS amplitude only in the minority of patients with LVH, and the low sensitivity of voltage criteria has been repeatedly documented 2, 3.
• ECG criteria for LVH have poor sensitivity in patients with hypertrophic cardiomyopathy, with the most common positive criterion being Cornell Voltage 3.
• T-wave inversion in limb and/or precordial leads is also a common finding in patients with LVH 3.
• The Cornell voltage product and multifactorial criteria, such as the Perugia criterion, allow detection of LVH in a higher proportion of subjects while carrying a high attributable risk for cardiovascular morbidity and mortality 4.

Relationship between ECG and Cardiovascular Magnetic Resonance Imaging

• Conventional assessment of LVH using the ECG has relied on assessing changes in the amplitude and/or duration of the QRS complex to quantify LV mass 5.
• ECG measures of LV mass have typically been validated by imaging with echocardiography or cardiovascular magnetic resonance imaging (CMR) 5.
• CMR has emerged as a tool to not only quantify LV mass but also detect and quantify the extent and severity of focal or diffuse myocardial fibrosis, edema, inflammation, myocarditis, fatty replacement, myocardial disarray, and myocardial deposition of amyloid proteins (amyloidosis), glycolipids (Fabry disease), or iron (siderosis) 5.

Clinical Implications

• ECG remains the first line method for detection of LVH in patients with hypertension, and ECG diagnosis of LVH predicts a several-fold increase in age- and risk factor-adjusted cardiovascular morbidity and mortality in asymptomatic patients with essential hypertension 4.
• Blood pressure control with lifestyle changes and antihypertensive agents has been demonstrated to prevent and regress LVH 6.