Background: In acute heart failure (AHF), right ventricular dysfunction (RVD) on inpatient echocardiogram predicts adverse outcomes (long term mortality, worsening renal function, need for higher dose IV vasodilators and diuretics, increased length of stay, and new onset atrial fibrillation). Emergency Physician (EPs) have demonstrated the ability to identify RVD using point-of-care ultrasound (POCUS) in the setting of pulmonary embolus, but RV function has never been assessed prior to initiation of treatment for AHF. The goal of this study was to assess the association of RVD at ED arrival with severity of illness and ED recidivism in patients with AHF.
Methods: In this prospective observational pilot study of 36 AHF patients, POCUS was performed by an EP at ED arrival (prior to treatment) and again at 24 hours. Treating EPs were blinded to US results. RVD was defined by two methods: tricuspid annular plane systolic excursion (TAPSE) < 17 mm or free wall RV longitudinal strain (RVLS) > -16. The primary outcome was the association of RVD at presentation with ED revisit for AHF within 30 days. Secondary outcomes included intensity of treatment, hospital LOS, and change in RV function at 24 hours. Odds ratios were used to compare associations of categorical variables; change in RV function at 24 hours was assessed with a paired t-test.
Results: 32 patients had suitable US images for TAPSE and 35 for RVLS. RVD at 0 hours was 74% by RVLS and 53% by TAPSE. Presence of RVD was associated with the primary outcome (TAPSE OR=5.1 [95%CI 2.3-11.7]; RVLS OR=2.8 [95%CI 1.1-6.7]). RVD by TAPSE predicted the need for IV nitroglycerin (OR=3.7; 95%CI 1.7-8.0), while RVLS predicted the need for BiPAP (OR=15.7; 95%CI 3.5-70.6). RVLS improved at 24 hours (mean 0 vs 24-hour -11.4 vs. -14.4, p=0.04), with lower prevalence of RVD (53% by RVLS).
Conclusion: RVD is highly prevalent at ED presentation for AHF and decreases by 24 hours to levels consistent with the existing literature. Patients with RVD at arrival received more aggressive ED interventions (IV nitroglycerin and BiPAP) and had higher ED recidivism. This is the first report of a role for RVD assessment in ED risk-stratification of AHF. Further study in a larger population is needed to better define the associations observed, further delineate interactions with confounders, and measure effects of specific treatments on projected course.