Abstract 10427: Association Between Blood Pressure Levels and Prevalence of Premature Atrial Contractions in Patients With Hypertension

Abstract

Background: High blood pressure (BP) leads to left atrial functional and structural abnormalities, which is the substrate for atrial arrhythmias. We hypothesized that, among patients with hypertension, higher levels of systolic BP (SBP) would be associated with a higher prevalence of premature atrial contractions (PACs), the most common cardiac arrhythmia that has been associated with poor outcomes in the general populations. Methods: This analysis included 4,497 (mean age 62.1±13.2 years, 49.9% women, 48.9% Whites) participants with hypertension from the Third National Health and Nutrition Examination Survey who were free of clinical cardiovascular disease (CVD). Multivariable logistic regression analysis was used to examine the cross-sectional association between SBP and the prevalence of PACs ascertained from electrocardiograms (ECGs) read at a central ECG core. Multivariable Cox proportional hazard analysis was used to examine the association between baseline PACs and CVD mortality occurring during follow-up. Results: About 1.6% (n=74) of the participants had PACs at baseline. Patients with SBP <140/<90 mmHg had lower prevalence of PACs compared to those with SBP > 140/≥90 mmHg (1.12% vs. 1.99%, p-value=0.019). Each 10 mmHg lower in SBP was associated with 11% lower odds of PACs in a multivariable logistic regression model adjusted for demographics, CVD risk factors, and major ECG abnormalities (OR (95%CI): 0.89 (0.78-1.02)). A total of 645 CVD deaths occurred during 14 years of follow-up. Presence (vs. absence) of PACs was associated with a 70% increased risk of CVD mortality in Cox models adjusted for demographics, CVD risk factors, and major ECG abnormalities (HR (95%CI): 1.70 (1.14-2.52)). Conclusions: Among patients with hypertension, presence of PACs is associated with an increased risk of CVD mortality, and lower levels of BP are associated with a lower prevalence of PACs. These findings highlight the potential role of intensive BP lowering in managing cardiac arrhythmias in hypertension patients.