Digital Interface for Cardiac Activation Mapping System

Kevin Khan, Karol Pawlina, Lorenzo Dimagiba
supervised by Dr. K. Umapathy & Mr. S. Masse

Originated and supported by the collaborative efforts of Mr. S. Masse, Mr. E. Sevaptsidis, Dr. K. Nanthakumar, Toronto General Hospital.

Cardiac arrhythmias can be caused by various issues and in some instances its cause is not easily found. In these cases where the arrhythmia is not readily known, a cardiac activation mapping system is used to isolate the specific problem area, allowing a qualified doctor to ablate. The purpose of this project was to update the cardiac activation mapping system currently used at the Toronto General Hospital. This system is capable of mapping the electrical activity of the heart in 224 different locations. Currently, there are a few issues with the system. One of the problems is that the system uses two outdated means of communication to interface with the computer; RS-232, and a proprietary hospital produced cable called the "Ikon" cable. By today's standards, both of these communication methods are phasing out, and as such a more updated form of communication is needed. Another problem which relates to communication is the fact that the system can only work with two computers, highly limiting its flexibility. Finally, the physical dimensions of the machine are quite large which makes it cumbersome to transport as needed.

The main scope of this project was to bring new life to the current system and address two of the previously mentioned problems by updating the communication peripherals. As stated above the current system uses RS 232 and an "Ikon" cable. Eventually support and use of these two cables will no longer exist and the system will become useless. To remedy this problem the students were asked to design a controller card which implemented the use of a single USB cable to replace the function of both the RS- 232 and "Ikon" cable. Implementing the use of a USB cable would increase the longevity of the system, as well as increase its flexibility since it would be compatible with more computers. This project involved three main components: hardware, microcontroller, and LabVIEW. Furthermore, there were three necessary functions which had to be performed by the new system, namely: setting gain, reading gain, and data acquisition.

Overall this project is a stepping stone to creating a more portable robust system capable of mapping arrhythmias with a high degree of precision. This project is also proudly demonstrating the ingenuity of Ryerson Biomedical Engineering program in conjunction with Toronto Generals Cardiac Lab.

Project targeted applications: