Abstract 11261: Impact of Baseline Heart Failure on RV:LV Diameter Ratio in Patients with Acute Pulmonary Embolism

Abstract

Introduction: Among patients with acute pulmonary embolism (PE), an elevated right ventricular to left ventricular diameter (RV:LV) ratio is associated with increased morbidity and mortality. RV:LV cut-offs used to identify PE patients at elevated risk for adverse events range from 0.9-1.0. It is unclear whether this cut-off should be used for PE risk stratification among patients with heart failure (HF), who may have abnormal cardiac chamber dimensions. Methods: Patients diagnosed with acute PE between 2010 and 2015 at the University of Toledo Medical Center were identified. Patients were categorized as: no HF, heart failure with reduced ejection fraction (HFrEF), and heart failure with preserved ejection fraction (HFpEF). No HF was defined as having no prior history of HF and an ejection fraction (EF) ≥ 50%. HFrEF was defined as history of HF and an EF < 50%. HFpEF was defined as history of HF and an EF ≥ 50%. Results: One hundred and eighty-three patients were identified for this study. Twelve patients were excluded due to missing EF records. Among the remaining 171 patients, 142 were categorized as no HF, 13 were categorized as HFrEF, and 16 were categorized as HFpEF. There were no significant differences in mean RV diameter between HFrEF [39.1 mm, standard deviation (SD) ± 5.9], no HF [36.9 mm, SD ± 7.5], or HFpEF [38.5 mm, SD ± 6.6] (p=0.575). However, mean LV diameter among patients with HFrEF was significantly higher [52.2 mm, SD ± 7.2] compared to no HF [38.1 mm, SD ± 8.3] and HFpEF [42.1 mm, SD ± 6.6] (p<0.001). Median RV:LV ratio was 0.77 [interquartile range (IQR) 0.65-0.89] for HFrEF, 0.91 [IQR 0.79-1.17] for no HF, and 0.89 [IQR 0.80-1.04] for HFpEF (p=0.024). Conclusions: Patients with HFrEF who presented to the hospital with acute PE had significantly higher mean LV diameter and lower RV:LV ratio compared to patients with HFpEF or no HF. These results suggest that risk stratification using current RV:LV ratio guidelines may underestimate PE risk among patients with HFrEF.