Electrocardiographic Versus Echocardiographic Left Ventricular Hypertrophy in Prediction of Congestive Heart Failure in the Elderly

BACKGROUND: Left ventricular hypertrophy (LVH) is an established risk factor for heart failure (HF) and is a component of the Framingham Heart Failure Risk Score (FHFRS). Whether LVH detected by electrocardiogram (ECG-LVH) is equally predictive of HF as LVH detected by echocardiography (echo-LVH) is unclear. HYPOTHESIS: ECG-LVH and echo-LVH are equally predictive of HF. METHODS: This analysis included 4543 participants (85% white; 41% male) age ≥ 65 years from the Cardiovascular Health Study who were free of HF at baseline. Incident HF was identified during a median follow-up of 12 years. ECG-LVH was defined by the Cornell criteria. Echo-LVH was defined as left ventricular mass > 95th percentile (male, > 212 g; female, > 175 g). Cox proportional hazard regression was used to examine the association between ECG-LVH and echo-LVH, separately with incident HF. Harrell's concordance C-index was calculated for the FHFRS with inclusion of ECG-LVH and echo-LVH, separately. RESULTS: At baseline, 168 participants had ECG-LVH and 226 had echo-LVH. A total of 1380 incident HF events occurred during follow-up. Both ECG-LVH and echo-LVH were predictive of incident HF (for ECG-LVH, hazard ratio: 1.39, 95% confidence interval CI: 1.08-1.77; for echo-LVH, hazard ratio: 1.52, 95% CI: 1.22-1.89). The ability of the FHFRS to predict HF was similar when ECG-LVH (C-index: 0.772, 95% CI: 0.726-0.815) and echo-LVH (C-index: 0.772, 95% CI: 0.727-0.814) were included into the model separately. CONCLUSIONS: Both LVH-ECG and echo-LVH are equally predictive of incident HF and can be used interchangeably in HF risk-prediction models.