Related Experiment Video
Updated: Oct 23, 2025

Cutoff Value of Phase Angle by Bioelectrical Impedance Analysis at Admission as a Prognostic Factor in Patients with Acute Heart Failure
Published on: June 10, 2025
Prevalence and determinants of the precursor stages of heart failure: results from the population-based STAAB cohort
Caroline Morbach1,2, Götz Gelbrich1,3,4, Theresa Tiffe1,3
1Comprehensive Heart Failure Center, University and University Hospital Würzburg, Germany.
Insights
A new group of asymptomatic individuals with cardiac dysfunction, termed "B-not-A," were identified. These individuals lack traditional heart failure risk factors, highlighting a gap in current primary prevention strategies.
Area of Science:
- Cardiology
- Preventive Medicine
- Population Health
Background:
- Heart failure prevention hinges on early identification and management of risk factors.
- Conventional strategies may miss individuals at risk who do not present with established risk factors.
Purpose of the Study:
- To determine the prevalence and characteristics of individuals at risk for heart failure in the general population.
- To identify individuals with precursor stages of heart failure (Stages A and B).
Main Methods:
- Cross-sectional analysis of the prospective Characteristics and Course of Heart Failure Stages A-B and Determinants of Progression (STAAB) cohort study.
- Stratified sampling by sex and age groups (30-79 years) in Würzburg, Germany.
- Definition of heart failure precursor stages A (risk factors) and B (asymptomatic cardiac dysfunction) per ACC/AHA guidelines.
Main Results:
- Stages A and B heart failure precursors were prevalent in 42% and 17% of participants, respectively.
- A distinct subgroup (31% of Stage B) lacked Stage A risk factors (group 'B-not-A').
- The 'B-not-A' group was younger, more frequently female, and predominantly characterized by left ventricular dilation compared to Stage B individuals with Stage A criteria.
Conclusions:
- A novel group of asymptomatic individuals with cardiac dysfunction and no traditional risk factors ('B-not-A') was identified.
- This group may be overlooked by current primary prevention efforts for heart failure.
- Further research is needed to validate these findings and explore the clinical trajectory and genetic profiles of the 'B-not-A' group.
Aims:
Prevention of heart failure relies on the early identification and control of risk factors. We aimed to identify the frequency and characteristics of individuals at risk of heart failure in the general population.
Methods And Results:
We report cross-sectional data from the prospective Characteristics and Course of Heart Failure Stages A-B and Determinants of Progression (STAAB) cohort study investigating a representative sample of residents of Würzburg, Germany. Sampling was stratified 1:1 for sex and 10:27:27:27:10 for age groups of 30-39/40-49/50-59/60-69/70-79 years. Heart failure precursor stages were defined according to American College of Cardiology/American Heart Association: stage A (risk factors for heart failure), stage B (asymptomatic cardiac dysfunction). The main results were internally validated in the second half of the participants. The derivation sample comprised 2473 participants (51% women) with a distribution of 10%/28%/25%/27%/10% in respective age groups. Stages A and B were prevalent in 42% and 17% of subjects, respectively. Of stage B subjects, 31% had no risk factor qualifying for stage A (group 'B-not-A'). Compared to individuals in stage B with A criteria, B-not-A were younger, more often women, and had left ventricular dilation as the predominant B qualifying criterion (all P < 0.001). These results were confirmed in the validation sample (n = 2492).
Conclusion:
We identified a hitherto undescribed group of asymptomatic individuals with cardiac dysfunction predisposing to heart failure, who lacked established heart failure risk factors and therefore would have been missed by conventional primary prevention. Further studies need to replicate this finding in independent cohorts and characterise their genetic and -omic profile and the inception of clinically overt heart failure in subjects of group B-not-A.
Related Concept Videos
Heart Failure IV: Classification and Diagnostic Evaluation
Pathophysiology of Heart Failure
Heart Failure I: Introduction
Heart Failure II: Pathophysiology
Heart Failure III: Clinical Manifestations
Mitral Regurgitation I: Introduction

