1. Department of Cardiac Surgery and Research Group for Experimental Surgery, Medical Faculty and University Hospital Düsseldorf Heinrich Heine University Hospital Moorenstr. 5 Düsseldorf 40225 Germany
2. Department of Cardiovascular Surgery Tohoku University Graduate School of Medicine Seiryocho, Aoba‐ku Sendai 980‐8574 Japan
3. Department of Cardiology, Angiology and Pulmonology, Medical Faculty and University Hospital Düsseldorf Heinrich Heine University Hospital Moorenstr.5 Düsseldorf 40225 Germany