Key to the foetus heart

“Heart defects have distinctive, unique features due to which they can be diagnosed more easily in prenatal life. We called these important features patterns and analysed them based on the stored ultrasonographic images as 3D volume files. The three-dimensional technique allowed us to precisely introduce these blocks of information in accordance with the principles of anatomy and thanks to this we were able to learn the features of geometric differences for most congenital heart defects. The geometric approach can easily be translated into perception of a doctor performing prenatal ultrasonographic examination,” Marcin Wiecheć, MD, of the Department of Gynaecology and Obstetrics of Collegium Medicum at the Jagiellonian University and the Perinatology Clinic of the University Hospital in Krakow said in conversation with Poland.pl.

The model of foetal heart developed by your team is a breakthrough in the world of prenatal diagnostics. Why does diagnosing defects of this organ in unborn children cause so much trouble for gynaecologists?

Marcin Wiecheć, MD: Interpreting the prenatal image in congenital anomalies has always been a great challenge for doctors and despite enormous progress in this field the group of specialists consulting these difficult cases is not too large. I have been considering the cause of this state of affairs since the beginning of my career in 2000 and came to the conclusion that one of the possible reasons is the lack of three-dimensional look views of the examined structures. For the first years, I did not have this awareness and in retrospect, I did not examine them very carefully. I had access to the first devices with three-dimensional software in 2005. I conduct studies on the interpretation of the image for diagnosis, especially in the field of congenital heart defects, together with Dr Agnieszka Nocuń who has been studying 3D from the very beginning and, in my opinion, this made her professional and scientific development path easier. In my case, the baggage of a two-dimensional view did not allow me to pay attention to the previously mentioned geometric patterns from the very start. The culmination of our observations is the three-dimensional print-out project, which gives an accessible insight to the geometrical differences inherent in the individual types of congenital heart defects.

Our models are designed to stimulate the imagination of a learning doctor in the same way that Lego bricks stimulate child's development. These models are also an invaluable tool for consultation, allowing parents to understand potential problems in the situation where a congenital defect is detected in their child.

You have focused primarily on defects of the heart.

I believe that the study of prenatal ultrasonography should start from the heart, because it is a difficult, but at the same time clear and a logical part of the issue. Not only are different techniques of ultrasonographic imaging combined in this area, the anatomical and functional analysis of a complex organ also appears in the process. We focused on the geometrical aspect, which allows a physician to conduct examinations to detect features within specific defects or groups of defects.

This is particularly important when learning to recognise difficult defects of vascular conus, such as tetralogy of Fallot, d-type or l-type tyletransposition of the great arteries, double outlet right ventricle or the common arterial trunk. By being familiar with geometric patterns, doctors, even at the initial stage of competence, can detect congenital heart defects more quickly. We are working on the analysis of image interpretation on a group of experts and training doctors with regards to the time of visual fixation on individual examined elements and we are recording the conclusions drawn from the examination by the physicians depending on the level of competence. Thanks to training focused on geometrical aspects based on our method using the 3D print-outs we are now able to shorten the time of interpretation of the image to several seconds, which traditionally used to take 30 minutes and sometimes even one and a half hours.

What is the secret behind your method?

Three-dimensional ultrasound as a diagnostic method in the case of prenatal diagnosis of congenital heart defects has its limitations, mainly due to the mobility of the foetus and the not always convenient position needed to provide an effective 3D record depicting the congenital defect. The obstacle lies mainly in the so-called acoustic shadowing due to which the heart is concealed for ultrasound. The obstacle to recording may be the ribs or even a forearm in front of the rig cage leading the three-dimensional record to be ineffective. However, the interpretation becomes simple thanks to the geometric patterns of birth defects. It should be highlighted that physicians who examine the foetal heart are mainly gynaecologists, whose interests do not focus on paediatric cardiology or cardiac surgery. In our case, thanks to active cooperation with associate professor Jacek Kołcz, cardiac surgeon, and Dr Zbigniew Kordon, a paediatric cardiologist, we can discuss the most difficult cases with them. However, within the reality of daily work it is hard to imagine that every foetus will be examined from the cardiologic side by a cardiologist and a cardiac surgeon, from the neurological side by a neurosurgeon, urological by a urologist, bone by an orthopaedist etc. The key is, in my opinion, to support gynaecologists in order to be able to effectively improve detection of congenital defects by them. Experts will not examine every pregnant woman in Poland and it will never be possible. Based on our observations, the concept of geometric patterns of congenital heart defects using the three-dimensional models is a simple and repeatable method which can help the first line doctors. 

How did you develop it?

Our idea was to develop three-dimensional models based on our library of 3D and 2D images. Many lecturers in ultrasound for gynaecologists only show the final processed product – the diagnosis. From the very beginning, I tried to show how to reach it in order to help my colleagues in their daily work. During my work teaching prenatal ultrasonography, I always try to imagine the way my colleagues with basic skills interpret the image and I consider how they can be directed in the simplest way to shorten the interpretation process. Three-dimensional models of normal foetal hearts and hearts with congenital defects serve this purpose. I think that with our three-dimensional models of the heart and a large library of ultrasound images we are able to create a situation where the science of diagnosing congenital heart defects will resemble the process when a grandfather teaches his grandson to recognise car brands – on the basis of their shape and characteristics. That is not all, when we know the patterns we will be able to recognise birth defects even with a poorer device and the best conditions of examination. I have been exploring the optimisation of the scanner and the adjustment of the image for as long as three years, so that the image on the screen was the cleanest, and today I know that it is only a supporting element. It is much more important, in my opinion, to understand the geometric relationship of the examined elements which is achieved thanks to three-dimensional print-outs.

Interview by Karolina Kowalska