Prevalence of undiagnosed stage B heart failure among emergency department patients

Introduction

Heart failure (HF) is associated with significant morbidity, mortality, and health care costs. Stage B HF is defined as structural heart disease prior to developing symptomatic HF. If identified early in the disease process, preventative measures may be implemented to slow disease progression to Stage C (symptomatic) or Stage D (refractory) HF. Previous research has focused on outpatient screening for HF in the primary care setting; however, there are limited data on Stage B HF screening in the Emergency Department (ED) setting. The objective of this study was to determine the prevalence of undiagnosed Stage B HF among those with cardiovascular risk factors in the ED setting and identify which risk factors were associated with a greater risk of having Stage B HF.

Methods

A prospective, observational study was performed in a single, urban academic ED from 07/2023 to 05/2024. Inclusion criteria were age ≥ 45 years with hypertension, diabetes, obesity, coronary heart disease, previous cardiotoxic chemotherapy, or family history of HF. Exclusion criteria included signs or symptoms of HF, known history of HF, valvular disease, current atrial fibrillation, or primary language other than English. A focused cardiac ultrasound was performed and interpreted by ultrasound-fellowship trained emergency physicians. Sonographers assessed systolic function as ejection fraction <50 % using visual assessment in at least two different views. Sonographers assessed diastolic dysfunction as an E/A ratio < 0.8, or if ≥2 of the following were present: septal e' < 7 cm/s or lateral e' < 10 cm/s, E/e' ratio > 14, or left atrial volume > 34 mL/m². Descriptive statistics were performed, followed by comparative analyses and regression modeling.

Results

209 participants were included in the study, with a mean age of 60 years and 51.7 % women. Of these, 125 (59.8 %) had undiagnosed Stage B HF, with 13 (10.4 %) having systolic dysfunction and 112 (89.6 %) having isolated diastolic dysfunction. Among those with isolated diastolic dysfunction, 44 (39.3 %) were grade I, 66 (58.9 %) were grade II, and 2 (1.8 %) were grade III. Predictors of undiagnosed Stage B HF included age (odds ratio 1.06; 95 % CI 1.02 to 1.10) and BMI (odds ratio 1.06; 95 % CI 1.01 to 1.10).

Conclusion

A large majority of ED patients with cardiovascular risk factors had undiagnosed Stage B HF. Age and obesity were associated with a higher risk of Stage B HF. This provides an opportunity for early identification and intervention for patients with undiagnosed Stage B HF to reduce progression to more severe HF.