R Wave in aVL Lead is a Robust Index of Left Ventricular Hypertrophy: A Cardiac MRI Study

Area of Science:

• Cardiology
• Medical Imaging
• Electrocardiography

Background:

• The R wave in lead aVL (RaVL) correlates with left ventricular mass index (LVMI) in healthy individuals.
• Previous studies focused on patients without known cardiac disease.
• The utility of ECG criteria for LVH in complex cardiac conditions requires further investigation.

Purpose of the Study:

• To compare ECG criteria for left ventricular hypertrophy (LVH) with cardiac MRI (CMR) findings.
• To evaluate RaVL and other ECG parameters in patients with cardiomyopathy or conduction disorders.
• To establish reliable ECG-based indicators for LVH in diverse patient populations.

Main Methods:

• Cardiac MRI (CMR) and ECG were performed on 501 patients within 5 days.
• CMR-defined LVH cut-offs were established: 83 g/m² for men and 67 g/m² for women.
• Statistical analysis assessed correlations between ECG parameters and CMR-derived LVMI.

Main Results:

• RaVL independently correlated with LVMI in patients with and without myocardial infarction (MI).
• SV3 correlated with LVMI and LV enlargement only in patients without MI.
• An optimal RaVL cut-off of 1.1 mV showed 98.3% specificity and 19.6% sensitivity for LVH; a threshold of 1.0 mV is proposed for definitive LVH diagnosis.

Conclusions:

• RaVL is a reliable indicator of LVH across various clinical settings, with a univocal threshold of 1.0 mV.
• An algorithm using RaVL (below 0.5 mV to exclude, above 1.0 mV to establish LVH) and composite indices (0.5-1.0 mV) achieved 85% accurate classification.
• SV3 can augment RaVL's performance, particularly in cases of LV enlargement.