1. The STS National Database
Frederick L. Grover, MD, David M. Shahian, MD, Richard E. Clark, MD, Fred H. Edwards, MD 
The Annals of Thoracic Surgery 
Volume 97, Issue 1, Pages S48-S54 (January 2014)
DOI: /j.athoracsur
Copyright © 2014 The Society of Thoracic Surgeons Terms and Conditions

2. Fig 1
Richard E. Clark, MD.
The Annals of Thoracic Surgery  , S48-S54DOI: ( /j.athoracsur )
Copyright © 2014 The Society of Thoracic Surgeons Terms and Conditions

3. Fig 2
Fred H. Edwards, MD.
The Annals of Thoracic Surgery  , S48-S54DOI: ( /j.athoracsur )
Copyright © 2014 The Society of Thoracic Surgeons Terms and Conditions

4. Fig 3 (A) Richard P. Anderson, MD; and (B) Peter C. Pairolero, MD.
The Annals of Thoracic Surgery  , S48-S54DOI: ( /j.athoracsur )
Copyright © 2014 The Society of Thoracic Surgeons Terms and Conditions

5. Fig 4 Frederick L. Grover, MD.
The Annals of Thoracic Surgery  , S48-S54DOI: ( /j.athoracsur )
Copyright © 2014 The Society of Thoracic Surgeons Terms and Conditions

6. Fig 5
David M. Shahian, MD.
The Annals of Thoracic Surgery  , S48-S54DOI: ( /j.athoracsur )
Copyright © 2014 The Society of Thoracic Surgeons Terms and Conditions