Natural history of unrepaired bicuspid aortic valve at diagnosis: meta-analysis and reconstruction of time-to-event data

INTRODUCTION: While outcomes after surgical or transcatheter aortic valve replacement between bicuspid aortic valve (BAV) and tricuspid aortic valve have been reported, the natural history of unrepaired BAV is sparse in the literature.EVIDENCE ACQUISITION: The MEDLINE and EMBASE databases were searched to identify relevant studies. The search was conducted through February 2024. Time-to-event data was synthesized to reconstruct survival curves.EVIDENCE SYNTHESIS: A total of 20 studies were identified. Nine studies were included to reconstruct the Kaplan-Meier survival curves, enrolling 5819 patients with BAV. Expected survival was 97.6±0.2%, 91.9±0.4%, 84.3±0.6%, and 76.0±0.9% at 1-, 5-, 10-, and 15-year, respectively. Long-term survival was similar between patients with unrepaired BAV and the general population (HR 1.15, 95% CI: 0.86 to 1.55, I2=0). Five studies were included to synthesize freedom from cardiac surgery, enrolling 2962 patients. Expected freedom cardiac surgery were 88.5±0.6%, 82.1±0.7%, and 70.0±1.5% at 1, 5, and 10 years, respectively. The risk of thoracic aortic dissection was 0.06 per 100 patient years (95% CI: 0.01 to 0.12, I2=30%).CONCLUSIONS: The estimated survival of patients with BAV was 91.9% at 5 years and 84.3% at 10 years after the diagnosis. Survival of patients with BAV may be comparable to that of the general population. The need for an intervention to either aortic valve or thoracic aorta was 30% at 10 years.