Force sensing for cardiac catheterization

Project brief

Cardiac arrhythmia is a serious heart condition with potentially fatal consequences, if untreated. A large number of people worldwide are affected by it. In the United States of America alone, the number of cardiac arrhythmia cases is estimated to around 1% of the overall population. The current treatment approach is to subject patients to a minimally invasive procedure, called cardiac ablation. During this procedure physicians with the visual aid of an x-ray fluoroscope insert catheters through small openings in the blood arteries of the patient. The objective is to reach and isolate the abnormally behaving heart by applying ablation lines that block the erroneous electrical signals that cause arrhythmias.

Accurate navigation of the catheter to the correct heart location is a difficult procedure and the quality of the final outcome depends to a large extent on the experience of the physician conducting the procedure. In addition, the employed fluoroscope emits harmful radiation and provides images with poor soft tissue contrast. Therefore, the physicians rely to quite an extent on their tactile sensation to realize appropriate ablation contact points. In many cases, the frictional forces between the catheter shaft and heart walls hinder the physician to accurately sense the catheter tip contact forces only from the tactile information relayed to their hands via the catheter handle. The mechanical contact of the catheter tip with the cardiac walls is seen to be an important, missing parameter that could quantify the quality of an ablation point and thus make the procedure more reliable. With the aim to provide the cardiac physician with improved force information from the catheter tip during an ablation procedure, this research project proposes novel miniaturized force sensors that can be integrated at the tip of the cardiac catheter. With a view on recent developments in the area of MRI guided cardiac interventions, the proposed sensor was created to conform to all standard MR compatibility requirements. This important contribution of this research will enable physicians to conduct cardiac procedures in a non-invasive environment with clear benefits to patients and medical team and at the same time obtain vital force information from the remote catheter tip inside the heart.