Received: 25 June 2020
Accepted: 27 July 2020
First Online: 31 July 2020
Ethics approval and consent to participate
: Given the retrospective nature of the current study, the requirement for informed consent was waived. The study protocol was approved by the Clinical Research Ethics Committee of Beijing Anzhen Hospital, Capital Medical University.
: Not applicable.
: The authors declare that they have no conflicts of interest.