Optimization of Cardiac Resynchronization Therapy by Non-Invasive Imaging of Cardiac Electrophysiology

Optimization of Cardiac Resynchronization Therapy by Non-Invasive Imaging of Cardiac Electrophysiology: A Pilot Study

The principal aim is to analyze total left and right ventricular activation time in different CRT device programming algorithms (SyncAV) measured by non-invasive electrophysiology

Patient specific anatomic parameters taken from the cardiac magnetic resonance examination will be the base for a semiautomatic model incorporating the conductivity of the heart, the lungs, blood and the torso. For this reason, a software package (AMIRA Developer, TGS Template Graphics Software, France) has been adapted to calculate a quasi static approximation of Maxwell equations.

After fusion of the T1 CMR scan and the ECG electrodes a model-based bidomain FEM is used for a step-wise measurement of the local activation times (resting potential: 290 mV; plateau: 0 mV; acceleration time: 3 ms) both Ende- and epicardially.

Inclusion Criteria:

• patients after successful implantation of a CRT-D or CRT-P device in whom a cardiac magnetic resonance examination is possible and the device is equipped with the SyncAV® programming software
• left bundle branch block before CRT implantation
• PQ interval ≤ 250 ms before implantation

Exclusion Criteria:

• high-grade AV block
• any contraindication concerning a safe CMR performance including claustrophobia
• terminal heart failure (NYHA IV) or cardiac decompensation
• life expectancy < 1 year
• women with child-bearing potential, pregnancy
• drug abusus