Measurement of fetal atrioventricular time intervals in fetal heart ultrasound – challenges in routine examination

Doppler ultrasound techniques are essential tools in the non­in­va­sive assessment of fetal cardiovascular func­tion, particularly for measuring atrioventricular (AV) time intervals. These measurements provide important in­for­ma­tion about the heart’s function and can aid in the diag­­no­­sis of fetal arrhythmias, especially heart blocks. We tried to evaluate how long does it take to obtain cardiac rhythm with measurable AV intervals by three Doppler methods in all cases. We used mitral and aortic Doppler, Ao and SVC Doppler, and pulmonary vein – pulmonary artery Dop­pler. The target was to obtain good images of all three in the same patient, without prolonging the examination time, and obtain them for 10 consecutive scans of different pa­tients. It took us 32 examinations (including the last 10 con­se­cu­tive cases) to arrive at proficiency using these three methods. Training with new techniques in everyday practice pre­pares us for those rare difficult situations. We should not live with the false impression that they are easy, because at the time we will need them, we will not only have to provide good images, but also reliable measurements that matter in the diagnosis.