Bernd Jung1, Daniela Foell2, Corinna Lang2, David Ziupa2, Gerlind Franke2, Stefanie Perez Feliz2, Michael Brunner2, Gideon Koren3, Manfred Zehender2, Katja E. Odening2
1Radiology, Medical Physics, University Medical Center, Freiburg, Germany; 2Cardiology, University Medical Center, Freiburg, Germany; 3Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Providence, United States
Transgenic LQT2 rabbits and wildtype controls were subjected to in vivo phase contrast MRI in a 1.5T MR-system to assess regional myocardial velocities in the LV (AHA 16-segment model). The same rabbits’ hearts were subsequently Langendorff-perfused and subjected to ex vivo epicardial monophasic action potential measurements to assess APD in the corresponding segments. Prolongation of cardiac repolarization and increased dispersion of APD lead to a globally and regionally impaired systolic and diastolic function in transgenic LQT2 rabbits. Moreover, regional APDs correlate with regional peak diastolic velocities indicating that Long-QT syndrome is not purely an electrical but rather an electromechanical disorder.
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