1. Royal Brompton HospitalLondon, United Kingdom
2. Chelsea & Westminster HospitalLondon, United Kingdom
3. Imperial College LondonLondon, United Kingdom
4. Brunel University LondonUxbridge, United Kingdom
5. Vrije Universiteit Brussel (VUB)Brussels, Belgium
6. Universitair Ziekenhuis Brussel (UZ Brussel)Brussels, Belgium