An Alternative Method to Calculate Simplified Projected Aortic Valve Area at Normal Flow Rate

Area of Science:

• Cardiology
• Echocardiography
• Valvular Heart Disease

Background:

• Simplified projected aortic valve area (EOAproj) is crucial for evaluating low flow low gradient aortic stenosis (LFLG AS).
• Current clinical use is limited by the complex calculation of flow rate (Q).

Purpose of the Study:

• To introduce a simplified, alternative method for calculating Q to be integrated into the EOAproj formula.
• To assess the agreement between the new EOAproj calculation method and the original one.

Main Methods:

• Retrospective observational study of consecutive patients with classic LFLG AS.
• Included patients with a Q variation of ≥ |15|% by dobutamine infusion using both calculation methods.
• Bland-Altman analysis was used to assess agreement between the two methods.

Main Results:

• Nine patients with LFLG AS met the inclusion criteria for statistical analysis.
• A systematic bias of 0.037 cm² was observed, with the new method overestimating EOAproj.
• Narrow 95% limits of agreement (-0.04 cm² to 0.12 cm²) indicate good concordance.

Conclusions:

• The new method for EOAproj calculation demonstrates narrow, clinically insignificant bias and limits of agreement.
• The proposed method is potentially interchangeable with the original, offering greater ease of implementation.
• Simplified calculations may enhance the clinical adoption and utility of EOAproj in LFLG AS management.