Right Ventricular Structure and Function Are Associated With Incident Atrial Fibrillation: MESA-RV Study (Multi-Ethnic Study of Atherosclerosis-Right Ventricle)

Abstract

Background: Right ventricular (RV) morphology has been associated with drivers of atrial fibrillation (AF) risk, including left ventricular and pulmonary pathology, systemic inflammation, and neurohormonal activation. The aim of this study was to investigate the association between RV morphology and risk of incident AF.

Methods and results: We interpreted cardiac magnetic resonance imaging in 4204 participants free of clinical cardiovascular disease in the MESA (Multi-Ethnic Study of Atherosclerosis). Incident AF was determined using hospital discharge records, study electrocardiograms, and Medicare claims data. The study sample (n=3819) was 61±10 years old and 47% male with 47.2% current/former smokers. After adjustment for demographics and clinical factors, including incident heart failure, higher RV ejection fraction (hazard ratio, 1.16 per SD; 95% confidence interval, 1.03-1.32; P=0.02) and greater RV mass (hazard ratio, 1.25 per SD; 95% confidence interval, 1.08-1.44; P=0.002) were significantly associated with incident AF. After additional adjustment for the respective left ventricular parameter, higher RV ejection fraction remained significantly associated with incident AF (hazard ratio, 1.15 per SD; 95% confidence interval, 1.01-1.32; P=0.04), whereas the association was attenuated for RV mass (hazard ratio, 1.16 per SD; 95% confidence interval, 0.99-1.35; P=0.07). In a subset of patients with available spirometry (n=2540), higher RV ejection fraction and mass remained significantly associated with incident AF after additional adjustment for lung function (P=0.02 for both).

Conclusions: Higher RV ejection fraction and greater RV mass were associated with an increased risk of AF in a multiethnic population free of clinical cardiovascular disease at baseline.

Keywords: atrial fibrillation; heart failure; heart ventricles; magnetic resonance imaging.

Figure 1

Study Sample

Figure 2

Survival Free of Atrial Fibrillation Stratified by Median Right Ventricular Mass and Function. Shown is estimated survival free of AF for study participants stratified by median RVEDM (top) and RVEF (bottom). Multivariable adjustment was for age, sex, race, body mass index, hypertension, diabetes, medication use (RAAS, β-blocker, anti-arrhythmic), smoking (status, pack-years), education level, and left ventricular hypertrophy. Adjustment was then additionally performed for respective LV parameter (i.e. LVEF for RVEF model; LVEDM for RVEDM model). Multivariable model for RVEDM does not include adjustment for left ventricular hypertrophy as adjustment for LV mass (i.e. LVEDM) is performed in the LV parameter-adjusted model. RV, right ventricular; LV, left ventricular; EF, ejection fraction; EDM, end-diastolic mass.

Figure 3

Schematic representation of the possible relationships between RV morphology and AF pathogenesis. Shown is a schematic reflecting the possible relationships between clinical phenotypes, systemic processes, and temporal changes in ‘at-risk’ RV morphology (early vs. late) in the context of AF pathogenesis. RV, right ventricle; EF, ejection fraction; HTN, hypertension, PH, pulmonary hypertension.