ECG Criteria for Left Ventricular Hypertrophy in Hypertensive Black Africans: Insights from the coArtHA Trial.

BACKGROUND

Electrocardiographic (ECG) criteria for detecting left ventricular hypertrophy (LVH) have largely been derived from non-African populations. Their diagnostic performance in Black African adults with untreated hypertension remains uncertain.

OBJECTIVE

To evaluate the diagnostic performance of established ECG-LVH criteria compared with echocardiographically assessed left ventricular mass index (LVMI) in Black African adults with untreated, uncomplicated hypertension enrolled in the coArtHA trial.

METHODS

In this subanalysis, we included 1,125 participants from rural Tanzania and Lesotho who underwent baseline 12-lead ECG and focused transthoracic echocardiography (fTTE). LVH was defined as LVMI > 95 g/m² in women, and >115 g/m² in men. Diagnostic performance of multiple ECG-LVH criteria was assessed using correlation analyses, sensitivity and specificity estimates, receiver-operating characteristic (ROC) analysis, including calculation of the area under the ROC curve (AUROC), and precision-recall curves (PRC).

RESULTS

Echocardiographic LVH was present in 56 (5%) participants. Across continuous ECG indices, Cornell voltage product adjusted by +0.8 mV in women showed the strongest association with LVMI (Spearman's rho = 0.37, p < 0.001). Among evaluated criteria, Cornell voltage product-based measures demonstrated the most consistent diagnostic performance across evaluated metrics, with an AUROC of approximately 0.76. Using established cut-off values, this criterion yielded a sensitivity of 64% and a specificity of 80%, whereas voltage-only criteria, including Multi-Ethnic Study of Atherosclerosis (MESA)- and Sokolow-Lyon-based indices, showed limited accuracy in this setting. Exploratory analyses of alternative cut-off values demonstrated the expected sensitivity-specificity trade-offs.

CONCLUSIONS

In this cohort of hypertensive Black African adults, ECG criteria showed a moderate association with LVMI by echocardiography. Among established ECG criteria, Cornell voltage product-based measures demonstrated the most consistent diagnostic performance. Diagnostic characteristics were strongly influenced by cut-off selection and clinical context, underscoring the need for population-specific evaluation and external validation of ECG criteria for LVH in African settings.

TRIAL REGISTRATION: Clinicaltrials.gov NCT04129840. Registered on October 17, 2019 (https://www.clinicaltrials.gov/).