Referenced in: none

Automatically associated channels: Kv11.1 , Kv7.1

Title: New echocardiographic insights in short QT syndrome: More than a channelopathy?

Authors: Simone Frea, Carla Giustetto, Michele Capriolo, Chiara Scrocco, Cristina Fornengo, Sara Benedetto, Francesca Bianchi, Stefano Pidello, Mara Morello, Fiorenzo Gaita

Journal, date & volume: Heart Rhythm, 2015 Oct , 12, 2096-105

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/26001507

Abstract
Short QT syndrome (SQTS) is a congenital ion channel disease characterized by an increased risk of sudden cardiac death. Little is known about the possibility that accelerated repolarization alters mechanical function in SQTS.The study investigated the presence of left ventricular dysfunction and mechanical dispersion, assessed by tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE), and their correlation with QT interval duration and genetics.Fifteen SQTS patients (7 with HERG and 3 with KCNQ1 mutation) were studied. Electrocardiographic and echocardiographic parameters were compared with age- and sex-matched healthy controls.When compared to the control group, SQTS patients showed reduced left ventricular contraction (global longitudinal strain: -16.0% ± 3.4% vs -22.6% ± 1.7%, P < .001; myocardial performance index 0.59 ± 0.17 vs 0.34 ± 0.08, P < .001) and a higher incidence of ejection fraction <55% (odds ratio 11, 95% confidence interval 1.045-374, P = .04). Mechanical dispersion assessed by TDI (P < .01) and STE (P < .001) was higher in the SQTS group than in controls; each parameter showed a significant inverse correlation with QT interval but not with QT dispersion.This study showed that in SQTS systolic function may also be affected. SQTS patients presented a significant dispersion of myocardial contraction. TDI and STE could become part of the evaluation of this rare disease.