Senior Design

September 9, 2003


Dr. Mark Wathen is a cardiologist experimenting with Implanted Cardiovertor Defibrillators (ICD) to continuously monitor heart rhythm for arrhythmias and to initiate an interventions (shock) as needed. Dr. Wathen is concerned with the way current devices detect and treat the arrhythmias and needs a biomedical engineer like you to help out with the next generation design. Here is what Dr. Wathen has shared with us so far about the situation.


What we know about the ICD is that it must first detect tachycardias and then treat them as they occur in real time in an automated fashion. This means that detection of arrhythmias is first based on heart rate.  However, the devices really want to treat only Ventricular Tachycardias (VT) (arising from the ventricles) and not Supraventricular Tachycardias (SVT)(which arise from the atria). The former are life threatening and the latter not. The treatment delivered by the ICD is a shock:  A LARGE and uncomfortable shock.  Thus the device needs to distinguish VT from SVT.  So, alternative techniques have developed to distinguish the 2 categories of tachycardia.  All work to date has utilized recordings only from a single site in the ventricle.  I am postulating that using 2 sites will permit differentiation of SVT from VT.  Should this idea work out, it has great potential for changing the industry’s reliance upon rate-based detection to some other form. 


  1. What do you need to do to test Dr. Wathen’s hypothesis that using 2 sites will permit differentiation of SVT and VT?


  1. At this time, what questions do you have for Dr. Wathen?


  1. How confident are you with this response to the question?


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  1. Identify any information you would like to have in order to be most effective in answering this question (e.g., I need a definition of … I need to know how to …. I don’t know the difference between….. etc.)