Atrial ectopy as a predictor of incident atrial fibrillation: A cohort study
ABSTRACT Atrial fibrillation (AF) prediction models have unclear clinical utility given the absence of AF prevention therapies and the immutability of many risk factors. Premature atrial contractions (PACs) play a critical role in AF pathogenesis and may be modifiable.
To investigate whether PAC count improves model performance for AF risk.
Prospective cohort study.
4 U.S. communities.
A random subset of 1260 adults without prevalent AF enrolled in the Cardiovascular Health Study between 1989 and 1990.
The PAC count was quantified by 24-hour electrocardiography. Participants were followed for the diagnosis of incident AF or death. The Framingham AF risk algorithm was used as the comparator prediction model.
In adjusted analyses, doubling the hourly PAC count was associated with a significant increase in AF risk (hazard ratio, 1.17 [95% CI, 1.13 to 1.22]; P < 0.001) and overall mortality (hazard ratio, 1.06 [CI, 1.03 to 1.09]; P < 0.001). Compared with the Framingham model, PAC count alone resulted in similar AF risk discrimination at 5 and 10 years of follow-up and superior risk discrimination at 15 years. The addition of PAC count to the Framingham model resulted in significant 10-year AF risk discrimination improvement (c-statistic, 0.65 vs. 0.72; P < 0.001), net reclassification improvement (23.2% [CI, 12.8% to 33.6%]; P < 0.001), and integrated discrimination improvement (5.6% [CI, 4.2% to 7.0%]; P < 0.001). The specificity for predicting AF at 15 years exceeded 90% for PAC counts more than 32 beats/h.
This study does not establish a causal link between PACs and AF.
The addition of PAC count to a validated AF risk algorithm provides superior AF risk discrimination and significantly improves risk reclassification. Further study is needed to determine whether PAC modification can prospectively reduce AF risk.
American Heart Association, Joseph Drown Foundation, and National Institutes of Health.
- Annals of internal medicine 12/2013; 159(11):787-8. DOI:10.7326/0003-4819-159-11-201312030-00014 · 16.10 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Premature ectopic beats are frequently detected on routine 12-lead screening-electrocardiogram (ECG). However, their prognostic importance in individuals without known cardiovascular disease (CVD) is not well established. We evaluated prognostic value of atrial premature complexes (APC’s) and ventricular premature complexes (VPC’s) detected by a single 12-lead-ECG. A prospective cohort of 7504 participants selected from nationally-representative, community-dwelling individuals living in United States, enrolled in the Third Health and Nutrition Examination Survey (NHANES-III) from 1988 – 94 with follow up through December 2006 without known CVD. The main outcomes were all – cause mortality, CVD related mortality and IHD related mortality. Out of 7504 participants (mean age 60 ± 14 years, 47% women, 49% whites), 89 (1.2%) had APC’s and 110 (1.5%) had VPC’s on 12 – lead ECG. During a follow up of up to 18 years, 2386 deaths occurred, of which 963 were due to CVD and 511 were due to IHD. In a multivariable adjusted for demographics, clinical variables and ECG measures, APC’s were significantly associated with all-cause mortality [HR, 1.41 (95% CI, 1.08-1.80)], CVD death [HR, 1.78 (95% CI, 1.26-2.44)] and IHD death [HR, 2.40 (95% CI, 1.59-3.47)]. For VPCs, however, there were no significant associations with all – cause mortality [HR, 1.05 (95% CI, 0.80-1.36)], CVD death [HR, 0.96 (95% CI, 0.62-1.43)] and IHD death [HR, 0.89 (95% CI, 0.47-1.52)]. In conclusion, APC’s, but not VPC’s, on routine screening ECG are predictive of adverse events in community-dwelling individuals without known CVD.The American journal of cardiology 07/2014; 114(1). DOI:10.1016/j.amjcard.2014.04.005 · 3.43 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Aims The long-term prognosis of subjects with supraventricular premature complexes (SVPCs) remains unclear in the general population. The aim of this study was to examine the prognostic significance of SVPCs in community-based health checkups. Methods and results We assessed 63 197 individuals (mean age, 58.8 ± 9.9 years; 67.6% women) who participated in annual community-based health checkups in 1993 and were followed until 2008. The primary endpoint was stroke death, cardiovascular death (CVD), or all-cause death during a 14-year mean follow-up, and the secondary endpoint was first atrial fibrillation (AF) event in subjects without self-reported heart diseases or AF at baseline. Compared with subjects without SVPCs, the multivariate-adjusted hazard ratios (HRs) [95% confidence interval (CI)] of stroke death, CVD, and all-cause death in subjects with SVPCs were 1.24 (0.98-1.56) for men and 1.63 (1.30-2.05) for women, 1.22 (1.04-1.44) for men and 1.48 (1.25-1.74) for women, and 1.08 (0.99-1.18) for men and 1.21 (1.09-1.34) for women, respectively. Atrial fibrillation occurred in 386 subjects during the follow-up (1.05/1000 person-years). The presence of SVPCs at baseline was the significant predictor of AF onset [HRs (95% CI): 4.87 (3.61-6.57) for men and 3.87 (2.69-5.57) for women]. Propensity score matched analyses also revealed the presence of SVPCs was significantly associated with increased risks of AF incidence and CVD even after adjusting the potential confounders. Conclusion The presence of SVPCs in 12-lead electrocardiograms was a strong predictor of AF development, and associated with increased risk of CVD in general population. © Published on behalf of the European Society of Cardiology. All rights reserved.European Heart Journal 10/2014; 36(3). DOI:10.1093/eurheartj/ehu407 · 14.72 Impact Factor