Eur Heart J Cardiovasc Imaging (2013) 14 (3): 301. doi: 10.1093/ehjci/jes308 First published online: January 2, 2013

This paper has been formally withdrawn. Since publication, it has come to the attention of the Editor-in-Chief that this paper was submitted simultaneously to Ultrasound in Medicine and Biology which contravenes EHJ-CI's policy that manuscripts must be submitted exclusively to EHJ-CI and are accepted on the understanding that they have not been, and will not be, published elsewhere. There is no evidence that the scientific content of the manuscript has been compromised.