Received: 8 December 2017
Accepted: 29 January 2018
First Online: 13 February 2018
Ethics approval and consent to participate
: All procedures performed in the study were conducted in accordance with the ethical standards of the Regional Scientific Ethics Committee for Southern Denmark and with the ethical guidelines of the 1975 Declaration of Helsinki and its later amendments. The protocol was approved by the Regional Scientific Ethics Committee for Southern Denmark, reference number S20080140 and S20130169 (45023). Written informed consent for study participation and publication of study results were obtained from all individual participants included in the study.
: Author Bjarne L. Nørgaard has received research grant from Siemens, Edwards Lifesciences and Heartflow. All other authors declare that they have no competing interests.
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