Text and Data Mining valid from 2018-06-11
Received: 8 December 2017
Accepted: 29 May 2018
First Online: 11 June 2018
Ethics approval and consent to participate
: Approval to access data was obtained previously from the Minister of Health Office and the Portuguese Society of Cardiology. Ethics approval and consent to participate are not applicable to this study.
: The authors declare that they have no competing interests.
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