Association of metabolic syndrome with non-thromboembolic adverse cardiac outcomes in patients with atrial fibrillation.

Aims: Evidence suggests an excess risk of non-thromboembolic major adverse cardiac events (MACE) associated with atrial fibrillation (AF), particularly in individuals free of overt coronary artery disease (CAD). Metabolic syndrome (MetS) increases cardiovascular risk in the general population, but less is known how it influences outcomes in AF patients. We aimed to assess whether MetS affects the risk of MACE in AF patients without overt CAD. Methods and results: This prospective, observational study enrolled 843 AF patients (mean-age, 62.5 ± 12.1 years, 38.6% female) without overt CAD. Metabolic syndrome was defined according to the National Cholesterol Education Program. The 5-year composite MACE included myocardial infarction (MI), coronary revascularization, and cardiac death. Metabolic syndrome was present in 302 (35.8%) patients. At 5-year follow-up, 118 (14.0%) patients experienced MACE (2.80%/year). Metabolic syndrome conferred a multivariable adjusted hazard ratio (aHR) of 1.98 for MACE [95% confidence interval (CI), 1.23-3.16; P = 0.004], and for individual outcomes: MI (aHR, 2.00; 95% CI, 1.69-5.11; P < 0.001), revascularization (aHR, 2.33; 95% CI, 1.40-3.87; P = 0.001), and cardiac death (aHR, 2.59; 95% CI, 1.25-5.33; P = 0.011). Following the propensity score (PS)-adjustment for MetS, the association between MetS and MACE (PS-aHR, 1.87; 95% CI, 1.21-3.01; P = 0.012), MI (PS-aHR, 1.72; 95% CI, 1.54-5.00; P = 0.008), revascularization (PS-aHR, 2.18; 95% CI, 1.69-3.11; P = 0.015), and cardiac death (PS-aHR, 2.27; 95% CI, 1.14-5.11; P = 0.023) remained significant. Conclusion: Metabolic syndrome is common in AF patients without overt CAD, and confers an independent, increased risk of MACE, including MI, coronary revascularization, and cardiac death. Given its prognostic implications, prevention and treatment of MetS may reduce the burden of non-thromboembolic complications in AF.

Type 2 diabetes increases the long-term risk of heart failure and mortality in patients with atrial fibrillation.

AIMS: Impact of type 2 diabetes mellitus (T2DM) on non-thromboembolic outcomes in atrial fibrillation (AF) is insufficiently explored. This prospective cohort study of AF patients aimed (i) to analyse the association between T2DM and heart failure (HF) events (including new-onset HF), and all-cause and cardiovascular mortality, (ii) to assess the impact of baseline T2DM treatment on outcomes, and (iii) to explore characteristics of new-onset HF phenotypes in relation to T2DM status. METHODS AND RESULTS: Of 1803 AF patients (515/1288, with/without prior HF), 389 (22%) had T2DM at baseline. After 5 years of median follow-up, T2DM patients had an 85% greater risk of HF events [adjusted hazard ratio (aHR) 1.85; 95% confidence interval (CI) 1.51-2.28; P < 0.001], including a 45% increased risk for new-onset HF (1.45; 1.17-2.28; P = 0.015). T2DM conferred a 56% higher all-cause (1.56, 1.22-2.01; P = 0.003) and a 48% higher cardiovascular mortality (1.48; 1.34-1.93; P = 0.007). Fine-Gray analysis, with mortality as a competing risk, confirmed greater HF risk among T2DM patients. All risks were highest among insulin-treated patients. The prevalence of new-onset HF phenotypes was as follows: 67% preserved ejection fraction (HFpEF), 20% mid-range ejection fraction (HFmrEF) and 13% reduced ejection fraction (HFrEF). On time-dependent Cox regression, adjusted for baseline characteristics and an interim acute coronary event, T2DM increased aHRs for new-onset HFpEF (2.38; 1.30-4.58; P <0.001) and the combined HFmrEF/HFrEF (1.77; 1.11-3.62; P = 0.017). CONCLUSIONS: Atrial fibrillation patients with T2DM have independently increased risk of new-onset/recurrent HF events, cardiovascular and all-cause mortality, particularly when insulin-treated. The prevailing phenotype of new-onset HF was HFpEF; T2DM conferred higher risk of both HFpEF and HFmrEF/HFrEF.

Adverse cardiovascular outcomes in atrial fibrillation: Validation of the new 2MACE risk score.

BACKGROUND: In addition to thromboembolism, atrial fibrillation (AF) may also predispose to major adverse cardiovascular events (MACE) attributable to coronary artery disease (CAD), including myocardial infarction (MI). The 2MACE score (2 points - Metabolic syndrome and Age≥75years, 1 point - MI/revascularization, Congestive heart failure/ejection-fraction <40%, and thrombo-Embolism) was recently proposed to help identify AF patients at risk of MACE. We assessed the predictive validity of the 2MACE score for MACE occurrence in AF patients free of CAD at baseline. METHODS: Non-valvular AF patients (n=794) without CAD (mean-age, 62.5±12.1years, metabolic syndrome, 34.0%; heart failure/ejection-fraction <40%, 25.7%; thromboembolism, 9.7%) were prospectively followed for 5years, or until MACE (composite of non-fatal/fatal MI, revascularization and cardiovascular death). At inclusion, CAD was excluded by medical history, exercise-stress testing and/or coronary angiography. Also, the 2MACE score was determined. RESULTS: At follow-up, 112 patients experienced MACE (2.8%/year). The 2MACE score demonstrated adequate discrimination (C-statistic, 0.699; 95% confidence interval [CI], 0.648-0.750; P<0.001) and calibration (Hosmer-Lemeshow P=0.79) for MACE. The score was significantly associated with MACE, with the adjusted Hazard Ratio (aHR) of 1.56 (95%CI, 1.35-1.73; P<0.001). As for individual outcomes, the score predicted MI (n=46; aHR, 1.49; 95%CI 1.23-1.80), revascularization (n=32; aHR, 1.41; 95%CI, 1.11-1.80) and cardiovascular death (n=34; aHR, 1.43; 95%CI, 1.14-1.81), all P<0.001. CONCLUSIONS: The 2MACE score successfully predicts future MACE, including incident MI, coronary revascularization and cardiovascular death in AF patients free of CAD at baseline. It may have a role in risk-stratification and primary prevention of MACE in AF patients.