Text and Data Mining valid from 2018-10-02
Received: 22 March 2018
Accepted: 5 September 2018
First Online: 2 October 2018
Ethics approval and consent to participate
: This study has been approved by the Chinese PLA General Hospital Medical Ethics Committee and have therefore been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments. All persons gave their informed consent prior to their inclusion in the study.
: All the authors contributed substantially to the project and agreed for sending the manuscript to <i>Cardiovascular Ultrasound</i>. There is no competing interest and the data are available.
: The authors declare that they have no conflict of interests.
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