DGM · Concept

How does it work?

We explicitly note that for this figure, we made use of the LAT Hybrid annotation of the CARTO 3 (Biosense Webster). This data has been previously analyzed and published in accordance with the Declaration of Helsinki and was approved by the local Ethics Committee

General

Directed graph mapping - or DGM - is a program creating directed networks representing cardiac excitation.

You are able to load either computational, experimental and clinical datasets into the software

  • An example of computational data sets could be a simulation from OpenCARP or your own simulation tool
  • Experimental data sets of electrode recordings socks or needle electrodes can be used as well as the more common clinical recordings of a penta-ray, point-by-point electrode recorder, basket catheter or electrode grid of your beloved mapping system as they all represent the cardiac excitation

Processing your file

Depending on the file you will load, DGM will either use

  • The locations as well as the Local Activation Times (LATs) as calculated by your mapping system (e.g. CARTO 3 or RHYTHMIA)
  • Only the electrode locations. In this case, DGM will calculate the ECGs itself from the electrode recordings (e.g. CARTO 3)

In case you use your own simulation tool, the required format will be documented on this site once our software is released.

Once uploaded in the software, DGM will

  1. [1]   Calculate for each node the corresponding neighbours
  2. [2]   Derive a directed network from each node
  3. [3]   Merge all these networks in a smart way
  4. [4]   Create a DGM redistribution of the nodes

On these new nodes, the directed network protocol (1-2-3) is repeated and the cycles representing the reentrant pattern of your arrhythmia will be visualized

  1. [5]   as DGM loops
  2. [6]   more complex showing a DGM loopband

In addition, DGM can find focal sources, which are regions with only outgoing arrows.