1. Hope should not spring eternal
Jennifer S. Nelson, MD, MS 
The Journal of Thoracic and Cardiovascular Surgery 
Volume 157, Issue 3, Pages (March 2019)
DOI: /j.jtcvs
Copyright © 2018 The American Association for Thoracic Surgery Terms and Conditions

2. Congenital surgeons should feel confident about implanting a pacemaker after 7 to 10 days.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /j.jtcvs )
Copyright © 2018 The American Association for Thoracic Surgery Terms and Conditions