Syncope and All-Cause Mortality in Heart Failure: A Propensity Score-Matched Analysis

To examine the association between syncope and all-cause mortality in a large cohort of patients with heart failure (HF) with syncope.

We retrospectively identified a cohort of patients with HF and syncope from January 1, 2010, to December 31, 2015, and matched them in a 1:1 propensity analysis with patients with HF without syncope. A multivariable Cox regression model was used to estimate the association between syncope and the end point, all-cause mortality.

During the study period, 3449 patients with HF were diagnosed with syncope (mean ± SD age, 72.8±14.3 years). At 12 months follow-up, syncope was not an independent risk factor of all-cause mortality in overall patients with HF (hazard ratio [HR], 0.98; 95% CI, 0.91-1.04; P=.467), HF with preserved ejection fraction (EF) (HR, 1.02; 95% CI, 0.93-1.11; P=.686), HF with mid-range EF (HR, 0.92; 95% CI, 0.73-1.16; P=.494), or HF with reduced EF (HR, 0.94; 95% CI, 0.83-1.06; P=284). In the subgroup of those with cardiac implantable electronic devices, syncope significantly increased the risk of all-cause mortality in HF with reduced EF (HR, 1.28; 95% CI, 1.01-1.62; P=.038).

Syncope was not an independent risk of all-cause mortality for patients with HF but significantly predicted the all-cause mortality in the subgroup of patients with heart failure reduced EF with cardiac implantable electronic devices.