ETD

• Cardiac Pacing
• Cardiac simulation
• Closed-loop modeling
• Digital Twin
• Pacemaker testing
• Pationt-specific modeling

The growing complexity of modern cardiac pacemaker algorithms has introduced a non-
negligible risk of adverse device–patient interactions, most notably pacemaker-mediated ar-
rhythmias such as Endless Loop Tachycardia (ELT). Traditional open-loop testing procedures,
which rely on pre-recorded or synthetic cardiac signals, are inherently unable to capture the
bidirectional feedback between the implanted device and the cardiac substrate, leaving clini-
cally dangerous behaviors undetected. This thesis presents PaceMat, a novel MATLAB-based
closed-loop platform for the in-silico evaluation of cardiac pacing algorithms. Unlike exist-
ing frameworks built upon Timed Automata or Hybrid Automata networks, PaceMat inte-
grates a fully programmable dual-chamber pacemaker emulator with an anatomically detailed,
patient-specific cardiac electrophysiology model based on the monodomain reaction-diffusion
equation, solved on voxel-based geometries via the Smoothed Boundary Method with GPU ac-
celeration. The platform further incorporates rule-based fiber orientation assignment and an
explicit bidirectional model of the fast conduction system — including the atrioventricular
node and the His–Purkinje network — complemented by a comprehensive graphical user in-
terface that renders the entire simulation workflow accessible to non-expert users.