1. Department of Cardiology, Medical University Lublin
2. Department of Cardiology, The Children’s Memorial Health Institute
3. Department of Cardiac Surgery, The Children’s Memorial Health Institute
4. Children’s Department of District Hospital
5. Second Department of Cardiology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia in Katowice
6. Department of Cardiac Surgery, Świętokrzyskie Cardiology Center
7. Department of Cardiac Surgery, The Pope John Paul II Province Hospital
8. Department of Cardiology, The Pope John Paul II Province Hospital