1. Institute of Cardiology Jagiellonian University Medical College Krakow Poland
2. John Paul II Hospital Krakow Poland
3. Collegium Medicum The Jan Kochanowski University Kielce Poland
4. Provincial Polyclinical Hospital Torun Poland
5. First Department of Cardiology Leszek Giec Upper‐Silesian Medical Centre of the Silesian Medical University Katowice Poland
6. KCRI Krakow Poland