Received: 3 July 2018
Accepted: 15 August 2018
First Online: 22 August 2018
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. For this type of study, formal consent is not required. Informed consent was obtained from all individual participants included in the study.
: Not applicable.
: Luca Guerra has had honoraria as a lecturer from GE Healthcare. The other authors declare that they have no competing interests.
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