The purpose of this study is to investigate the safety of an investigational medication for children who need blood thinners due to heart conditions. Blood thinners are medicines that help prevent blood clots from forming. This study will compare the investigational medication to other commonly used blood thinners.
Participants in the study will follow certain procedures to help researchers gather information. These procedures may include taking the investigational medication and having blood tests to measure how much of the medication is in the body. This helps to understand how the medication is working.
- Who can participate: Children with heart diseases who need long-term blood thinners can join. They must be able to take medicine by mouth or through a feeding tube.
- Study details: Participants will take either the investigational medication or another blood thinner. Their blood will be tested to see how the medication is working.

