Kyu Ok Choe, Presenter: Nothing to Disclose

Hye-Jeong Lee MD, Abstract Co-Author: Nothing to Disclose

Young Joo Suh MD, Abstract Co-Author: Nothing to Disclose

Sae Rom Hong MD, Abstract Co-Author: Nothing to Disclose

Yoo Jin Hong MD, Abstract Co-Author: Nothing to Disclose

Young Jin Kim MD, Abstract Co-Author: Nothing to Disclose

Myocardial dyskinesia in segments prematurely activated by accessory pathways has been well documented in echocardiographic studies for pediatric WPW syndrome patients. However, the long-term effects of dyskinesia to the myocardium have not been studied in depth. Therefore, our study goal was to evaluate myocardial structural abnormalities on cardiac CT in adult WPW syndrome patients.

Institutional Review Board approval was obtained for this retrospective study and informed consent was waived. Of the 75 WPW syndrome patients who underwent cardiac CT from January 2006 to December 2013, 58 patients (mean age 51.8 ± 12.7 years, 62.1% male) were finally included after excluding combined cardiac disease. Clinical records including electrocardiography, electrophysiologic study, and echocardiography were evaluated. Two reviewers blindly and independently evaluated myocardial thickness and attenuation on cardiac CT retrospectively. The interobserver agreement about the presence of myocardial structural abnormality and the correspondence rate between the myocardial abnormality location and the accessory pathway location were evaluated.

For myocardial abnormality, excellent agreement (k=0.811) was obtained between the reviewers. After consensus, a total of 18 patients (31%) were found to have myocardial abnormalities; wall thinning in 17 patients, subendocardial fat attenuation in 10, and combined findings in 9. All findings were observed at the basal left ventricle. For the accessory pathways, 16 patients had the right free wall pathway, 11 had the septal pathway, and 31 had the left lateral pathway. No myocardial abnormality was observed at the right free wall pathway, and 6 patients with the septal pathway and 12 with the left lateral pathway showed myocardial abnormalities. All abnormalities (100%, 18/18) corresponded with the accessory pathway location.

A relatively high prevalence (31%) of myocardial structural abnormalities was observed on cardiac CT in adult WPW syndrome patients, and all abnormalities corresponded with the accessory pathway location.

Wall thinning and subendocardial fat attenuation observed in WPW patients might reflect long term effects of dyskinesia and might suggest irreversible myocardial injury.

Choe, K, Lee, H, Suh, Y, Hong, S, Hong, Y, Kim, Y, Detecting Myocardial Structural Abnormalities in Patients with the WPW Syndrome with ECG-gated Multi-detector Cardiac CT.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14010340.html