Echocardiographic diastolic parameters and risk of atrial fibrillation: the Cardiovascular Health Study

Abstract

Aims: Atrial fibrillation (AF) is the most common sustained arrhythmia in the elderly, and shares several risk factors with diastolic dysfunction, including hypertension and advanced age. The purpose of this study is to examine diastolic dysfunction as a risk for incident AF.

Methods and results: We examined the association of echocardiographic parameters of diastolic function with the incidence of AF in 4480 participants enrolled in the Cardiovascular Health Study, an ongoing cohort of community-dwelling older adults from four US communities. Participants underwent baseline echocardiography in 1989-1990 and were followed for incident AF on routine follow-up and hospitalizations. After 50 941 person-years of follow-up (median follow-up time 12.1 years), 1219 participants developed AF. In multivariable-adjusted age-stratified Cox models, diastolic echocardiographic parameters were significantly associated with the risk of incident AF. The most significant parameters were the Doppler peak E-wave velocity and left atrial diameter, which demonstrated a positive nonlinear association [HR 1.5 (CI 1.3-1.9) and HR 1.7 (CI 1.4-2.1) for highest vs. lowest quintile, respectively], and Doppler A-wave velocity time integral, which displayed a U-shaped relationship with the risk of AF [HR 0.7 (CI 0.6-0.9) for middle vs. lowest quintile]. Each diastolic parameter displayed a significant association with adjusted NT-proBNP levels, although the nature of the association did not entirely parallel the risk of AF. Further cluster analysis revealed unique patterns of diastolic function that may identify patients at risk for AF.

Conclusion: In a community-based population of older adults, echocardiographic measures of diastolic function are significantly associated with an increased risk of AF.

Figure 1

(A) Kaplan–Meier curve for quantiles of Doppler early mitral inflow velocity on survival free from atrial fibrillation, with adjustment for risk factors (see text). (B) KM curve for Doppler late mitral inflow velocity time integral. (C) KM curve for M-mode derived left atrial size.

Figure 2

BNP levels according to specified quantiles of Doppler early MV inflow velocity, late MV inflow VTI, and M-mode LA size, with adjustment for base model variables (see text for details). *P < 0.05 vs. lowest quintile. ^†P < 0.05 vs. middle quintile.