Screening-Detected Atrial Fibrillation Triples Heart Failure Risk, Study Finds

A new analysis of two large Swedish studies has found that individuals whose atrial fibrillation (AF) is detected during screening face a risk of developing heart failure that is three times higher than those without AF. The findings, presented at the EHRA 2026 congress, indicate this risk is comparable to that of patients with previously known AF, with heart failure diagnoses typically occurring within six months of AF detection.

"In individuals with screening-detected AF, the risk of developing HF was threefold that of participants without AF and comparable to that of patients with clinically known AF."

Study Design and Methodology

The findings are based on a post-hoc analysis of the Swedish STROKESTOP and STROKESTOP II studies. The original trials involved individuals aged 75–76 years who were randomized to receive ECG-based AF screening or to serve as control groups.

• Data Sources: Information on subsequent heart failure (HF) diagnoses and mortality was obtained from national registries.
• Follow-up Periods: The analysis used a median follow-up of 6.9 years for the STROKESTOP study and 5.1 years for the STROKESTOP II study.
• Statistical Analysis: Researchers used Cox regression models to estimate hazard ratios for the incidence of new heart failure diagnoses across different participant groups.

Key Findings

The analysis yielded consistent results across both studies.

• Screened Population: 6,824 individuals
• New AF Detected: 252 individuals
• Subsequent HF Diagnosis: 57 of the 252 individuals with screening-detected AF (23%)
• Risk Comparison: Screening-detected AF was associated with a threefold increased risk of heart failure compared to individuals without AF (adjusted Hazard Ratio 3.19; 95% Confidence Interval 2.42 to 4.21).
• Risk vs. Known AF: The heart failure risk for individuals with screening-detected AF was comparable to the risk for patients with previously known AF (adjusted HR 2.86; 95% CI 2.34 to 3.50).

• Screened Population: 6,601 individuals
• New AF Detected: 152 individuals
• Subsequent HF Diagnosis: 31 of the 152 individuals with screening-detected AF (20%)
• Risk Comparison: The study reported similar results regarding the increased risk of heart failure.

• Timing of Diagnosis: In both studies, heart failure was typically diagnosed early, within six months after the detection of atrial fibrillation.

Researcher Statement

Doctor Gina Sado from Danderyd Hospital in Stockholm, Sweden, presented the findings. Dr. Sado added that the findings "suggest that asymptomatic AF is not a benign condition and highlight the need for early detection of both AF and HF."

Dr. Sado also noted that while the bidirectional relationship between heart failure and atrial fibrillation—where each condition can accelerate the progression of the other—has been well studied in patients with clinically known AF, less was previously known about the incidence and timing of heart failure in individuals whose AF was detected during screening.

Disease Context and Background

• Global Prevalence: Atrial fibrillation is reported to affect nearly 38 million people worldwide, with its prevalence predicted to double over the next 35 years.
• Clinical Outcomes: While stroke is a widely recognized serious outcome of AF, heart failure also occurs frequently in patients with AF and is a major cause of death.
• Condition Relationship: Medical literature describes a bidirectional relationship between heart failure and atrial fibrillation, where each condition can influence and accelerate the progression of the other.