Atrial Fibrillation Worsens Right Ventricular Dysfunction and Outcomes in Acute Pulmonary Embolism

Atrial fibrillation (AF), both new-onset and preexisting, is associated with increased mortality in acute pulmonary embolism (PE). However, the underlying mechanism, whether through increased right ventricular dysfunction (RVD) or an alternative pathway, is less well understood. We conducted a retrospective, multicenter cohort study using data from our institutional Pulmonary Embolism Response Team (PERT) registry. Adults (age >18 years) with a PERT activation and a transthoracic echocardiogram (TTE) performed within 3 days of PE diagnosis were included. Patients were stratified by AF status (no AF vs preexisting or new-onset). TTE images were independently reviewed to assess for RVD. Outcomes were analyzed using univariate testing, multivariate regression, and Cox proportional hazards modeling. Among 785 patients with acute PE, 16% had AF. Compared with those without AF, patients with AF had higher unadjusted rates of RVD (33% vs 24%, p = 0.021) and significant differences in individual parameters including TAPSE (1.72 vs 1.9 cm, p = 0.006), S' (11.3 vs 13.4 cm/s, p < 0.0001) and RVOT VTI (12.5 vs 13.9 cm, p = 0.006). In adjusted analyses, AF remained significantly associated with RVD (OR 1.95, 95% CI 1.27-2.98, p = 0.002), inpatient mortality (OR 2.58, p = 0.03), acute renal failure (OR 1.75, p = 0.017), and 1-year mortality (HR 1.66, p = 0.02). These findings provide further evidence for the adverse prognostic impact of AF on acute PE mortality and suggest that RVD may be a key mediator. AF should be considered in acute PE risk stratification, and further studies are needed to evaluate targeted treatment strategies in this population.