How Do We Reconcile Echocardiography, Computed Tomography, and Hybrid Imaging in Assessing Discordant Grading of...

Area of Science:

• Cardiology
• Medical Imaging
• Valvular Heart Disease

Background:

• A significant portion of aortic stenosis (AS) patients exhibit "discordant grading," often termed "low-gradient AS."
• Accurate assessment of AS severity is crucial for appropriate patient management.

Purpose of the Study:

• To present an integrative, step-by-step approach for assessing AS severity, focusing on reconciling discordant grading.
• To outline the utility, limitations, and complementary roles of various imaging modalities in AS assessment.

Main Methods:

• Confirming echocardiographic measures of AS severity using hybrid imaging (e.g., 3D echocardiography, CT) with Doppler flow velocities.
• Utilizing low-dose dobutamine stress echocardiography to differentiate severe from non-severe AS in low-flow, low-gradient AS patients with reduced ejection fraction.
• Employing aortic valve calcium scoring via noncontrast CT in low-gradient AS with preserved ejection fraction or inconclusive dobutamine stress results.

Main Results:

• Hybrid imaging can validate AS severity by combining anatomical and hemodynamic data.
• Dobutamine stress echocardiography effectively distinguishes severe from non-severe AS in specific patient subgroups.
• Aortic valve calcium scoring provides a reliable alternative for assessing AS severity in select low-gradient cases.

Conclusions:

• An integrated imaging approach is essential for accurate AS severity assessment, particularly in cases of discordant grading.
• Combining echocardiography, stress echocardiography, and CT-based calcium scoring optimizes the evaluation of aortic stenosis.
• This systematic strategy aids clinicians in making informed decisions for patients with challenging AS assessments.