|Title||Electromechanical window negativity in genotyped long-QT syndrome patients: relation to arrhythmia risk.|
|Publication Type||Journal Article|
|Year of Publication||2015|
|Authors||Bekke RMA ter, Haugaa KH, van den Wijngaard A, J Bos M, Ackerman MJ, Edvardsen T, Volders PGA|
|Journal||Eur Heart J|
|Date Published||2015 Jan 14|
AIM: Prolonged and dispersed left-ventricular (LV) contraction is present in patients with long-QT syndrome (LQTS). Electrical and mechanical abnormalities appear most pronounced in symptomatic individuals. We focus on the 'electromechanical window' (EMW; duration of LV-mechanical systole minus QT interval) in patients with genotyped LQTS. Profound EMW negativity heralds torsades de pointes in animal models of drug-induced LQTS.
METHODS AND RESULTS: We included 244 LQTS patients from three centres, of whom 97 had experienced arrhythmic events. Seventy-six matched healthy individuals served as controls. QT interval was subtracted from the duration of Q-onset to aortic-valve closure (QAoC) midline assessed non-invasively by continuous-wave echocardiography, measured in the same beat. Electromechanical window was positive in controls but negative in LQTS patients (22 ± 19 vs. -43 ± 46 ms; P
CONCLUSIONS: Patients with genotype-positive LQTS express EMW negativity, which is most pronounced in patients with documented arrhythmic events.
|Alternate Journal||Eur. Heart J.|