Received: 1 May 2020
Accepted: 20 July 2020
First Online: 29 July 2020
Ethics approval and consent to participate
: Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. This cardiac surgical local registry was approved by the Hong Kong.Hospital Authority and the Government of Hong Kong SAR to allow collection, analysis, reporting and outcome tracking of patient data since its introduction in 2007.
: No informed consents from patients were sought for this retrospective analysis as there were no identifiers in this manuscript that could disclose individual patient confidentiality. All patient data had been secured and kept confidential.
: The authors declare that they have no competing interests.