First trimester fetal heart evaluation. A pictorial essay.

Area of Science:

• Obstetrics and Gynecology
• Fetal Medicine
• Diagnostic Ultrasound

Background:

• Fetal heart evaluation is traditionally performed in the second trimester.
• Emerging evidence indicates the feasibility of diagnosing congenital heart disease in the first trimester (FT).
• Trained specialists can enhance diagnostic accuracy during early pregnancy.

Purpose of the Study:

• To detail the specific ultrasound techniques for FT fetal heart evaluation.
• To provide practical guidance for basic and extended FT fetal heart assessment protocols.
• To emphasize the importance of early cardiac screening.

Main Methods:

• Utilized various ultrasound modalities including B-mode, Color Flow Mapping (CFM), Bidirectional Doppler, Spatio-Temporal Image Correlation (STIC), and Tomographic Ultrasound Imaging (TUI).
• Employed both transabdominal and transvaginal probe approaches.
• Recommended reassessment in the second trimester for abnormal FT findings.

Main Results:

• Congenital heart disease diagnosis is achievable in the FT with specialized ultrasound techniques.
• The study highlights the utility of B-mode, CFM, Doppler, STIC, and TUI for early fetal cardiac assessment.
• Not all cardiac anomalies are detectable in the FT, necessitating follow-up.

Conclusions:

• FT fetal heart examination should be attempted in all pregnancies, irrespective of risk factors.
• A basic Doppler examination protocol is recommended for all FT screenings.
• Early detection of fetal cardiac issues can be improved through standardized FT protocols.