BEEAF2 Score: A New Risk Stratification Score for Patients With Stage B Heart Failure From the KUNIUMI Registry Chronic Cohort

Abstract

Background: Stage B heart failure (HF) refers to structural heart disease without signs or symptoms of HF, so that early intervention may delay or prevent the onset of overt HF. However, stage B HF is a very broad concept, and risk stratification of such patients can be challenging.

Methods and results: We conducted a prospective study of data for 1646 consecutive patients with HF from the KUNIUMI (Kobe University Heart Failure Registry in Awaji Medical Center) registry chronic cohort. The definition of HF stages was based on current guidelines for classification of 29 patients as stage A HF, 761 as stage B HF, 827 as stage C HF, and 29 patients as stage D HF. The primary end point was the time-to-first-event defined as cardiovascular death or HF hospitalization within 2.0 years of follow-up. A maximum of 6 adjustment factor points was assigned based on Cox proportional hazards analysis findings for the hazard ratio (HR) of independent risk factors for the primary end point: 1 point for anemia, estimated glomerular filtration rate <45 mL/min per 1.73 m², brain natriuretic peptide ≥150 pg/mL, and average ratio of early transmitral flow velocity to early diastolic mitral annular velocity >14, and 2 points for clinical frailty scale >3. Patients with stage B HF were stratified into 3 groups, low risk (0-1 points), moderate risk (2-3 points), and high risk (4-6 points). Based on this scoring system (BEEAF₂ [brain natriuretic peptide, estimated glomerular filtration rate, ratio of early transmitral flow velocity to early diastolic mitral annular velocity, anemia, and frailty]), the outcome was found to become worse in accordance with risk level. High-risk patients with stage B HF and patients with stage C HF showed similar outcomes.

Conclusions: Our scoring system offers an easy-to-use evaluation of risk stratification for patients with stage B HF.

Keywords: echocardiography; preclinical heart failure; risk stratification; stage B heart failure.

Figure 1. Kaplan–Meier curve representing the primary end point for patients with stage A–D HF, showing that the more advanced the stage of HF is, the worse the prognosis for patients with HF becomes.

HF indicates heart failure; and HR, hazard ratio.

Figure 2. Receiver operating characteristic curve analysis of the risk stratification model for predicting primary end point for stage B heart failure.

AUC indicates area under the curve; and ROC, receiver operating characteristic. The dark blue line shows the ROC curve, and the light blue lines show the 95% confidence bounds.

Figure 3. Kaplan–Meier curve representing the primary end point for low‐risk, moderate‐risk, and high‐risk patients with stage B HF, showing that outcomes for moderate‐risk patients with stage B HF were better than for high‐risk patients but worse than for low‐risk patients.

HF indicates heart failure; and HR, hazard ratio.

Figure 4. Kaplan–Meier curve representing the primary end point for high‐risk patients with stage B HF and patients with stage C HF, showing similar outcomes.

HF indicates heart failure; and HR, hazard ratio.

Figure 5. Summary of our scoring system (BEEAF₂ score) for evaluation of risk stratification of patients with stage B HF.

BEEAF₂ indicates BNP, eGFR, E/e′, anemia, and frailty; BNP, brain natriuretic peptide; E/e′, ratio of early transmitral flow velocity to early diastolic mitral annular velocity; eGFR, estimated glomerular filtration rate; HF, heart failure; and HR, hazard ratio.