Tilt-table Echocardiography Unmasks Early Diastolic Dysfunction in Patients With Hemoglobinopathies

Area of Science:

• Cardiology
• Pediatric Hematology
• Diagnostic Imaging

Background:

• Hemoglobinopathies like sickle cell anemia and thalassemia major pose risks for cardiac complications, including heart failure and cardiomyopathy.
• Diastolic dysfunction often precedes systolic dysfunction in cardiac diseases.
• Early detection of subclinical cardiac abnormalities is crucial in managing these conditions.

Purpose of the Study:

• To investigate if tilt-table echocardiography can reveal subclinical diastolic dysfunction in pediatric patients with hemoglobinopathies by assessing left atrial (LA) function changes.
• To evaluate the impact of altered cardiac preload on LA function in these patients.

Main Methods:

• A tilt-table echocardiogram was performed on pediatric patients with sickle cell anemia (11), thalassemia major (9), and controls (10) in supine (loading) and upright (unloading) positions.
• Cardiac magnetic resonance imaging (MRI) was used to assess left ventricular (LV) function and myocardial iron deposition.
• Echocardiography measured LA and LV strain, strain rate, mitral inflow, and annular velocities.

Main Results:

• Both patient groups exhibited normal LV function and no cardiac iron deposition via MRI.
• In controls, cardiac loading increased LA conduit and reservoir strain, and mitral inflow velocities.
• Hemoglobinopathy patients failed to show these functional augmentations during cardiac loading, indicating impaired LA function.

Conclusions:

• Tilt-table echocardiography effectively unmasked impaired left atrial function in pediatric sickle cell anemia and thalassemia patients.
• This suggests the presence of altered myocardial relaxation, a form of subclinical diastolic dysfunction, predating iron overload or systolic dysfunction.
• This method offers a valuable tool for early cardiac risk assessment in hemoglobinopathies.