1 Praxis Leitz, Stuttgart, Germany
2 Royal-Berkshire Hospital, Reading
3 Department of Cardiology, University Hospitals Coventry and Warwickshire, Coventry CV2 2DX
Correspondence to: M Been [email protected]
Contributors: NL wrote the first draft of the article and prepared the illustrations. ZK helped with revisions and literature search. MB had the original idea for the article and supported NL and ZK in preparing the manuscript.
Competing interests: None declared.
Patient consent obtained.
Accepted: 11 September 2007
doi:10.1136/bmj.39489.687894.DE