Interrelation Between Electrocardiographic Left Atrial Abnormality, Left Ventricular Hypertrophy, and Mortality in Participants With Hypertension

Abstract

Left ventricular hypertrophy (LVH) and left atrial abnormality (LAA) are common correlated complications of hypertension. It is unclear how common for electrocardiographic markers of LAA (ECG-LAA) to coexist with ECG-LVH and how their coexistence impacts their prognostic significance. This analysis included 4,077 participants (61.2 ± 13.0 years, 51.2% women, 48.6% whites) with hypertension from the Third National Health and Nutrition Examination Survey. ECG-LVH was defined by Cornell voltage criteria. ECG-LAA was defined as deep terminal negativity of P wave in V1 >100 µV. Cox proportional hazard analysis was used to examine the associations between various combinations of ECG-LAA and ECG-LVH with all-cause mortality over a median follow-up of 14 years. The baseline prevalence of ECG-LVH, ECG-LAA, and the concomitant presence of both was 3.6%, 2.7%, and 0.34%, respectively. In a multivariable-adjusted model, mortality risk was highest in the group with concomitant ECG-LAA and ECG-LVH (hazard ratio [HR; 95% confidence interval {CI}] 2.69 [1.51, 4.80]), followed by isolated ECG-LAA (HR [95% CI] 1.63 [1.26, 2.12]), and then isolated ECG-LVH (HR [95% CI] 1.40 [1.08, 1.81]), compared with the group without ECG-LAA or ECG-LVH. Effect modification of these results by age and diabetes but not by gender or race was observed. In models with similar adjustment where ECG-LVH and ECG-LAA were entered as 2 separate variables and subsequently additionally adjusted for each other, the mortality risk was essentially unchanged for both variables. In conclusion, in participants with hypertension, ECG-LAA and ECG-LVH are independent markers of poor outcomes, and their concomitant presence carries a higher risk than either marker alone.