News
Dec 19, 2017

Dissertation, Fred-Johan Pettersen


 

.... CCI congratulates Fred-Johan Pettersen for successfully defending his PhD thesis "Bioimpedance as a tool in Cardiac resyncronisation therapy" during December 2017.

 

Electric bioimpedance (EB) is a measure of how different tissues are impeding an electric current in a volume conductor — in this case the heart and thorax region. The measured impedance is a function of the electrical properties of tissues and blood as well as a function of the geometry of tissues and electrode placements. This work has been aimed at enabling EB research in cardiology on human subjects, and in particular by using the CRT lead electrodes after the leads are placed, but before the CRT device is connected to the leads.

This thesis included the following papers; "Comparison of four different FIM configurations—a simulation study", "Optically isolated current source", "Bioimpedance measurements of temporal changes in beating hearts" and "Use of bioimpedance measurements to verify capture with biventricular pacing".
Category: General
Posted by: Piritta

Fred-Johan Pettersen
Bioimpedance as a tool in cardiac resyncronisation therapy

December 2017.

Of the patients who receive Cardiac Resynchronisation Therapy (CRT) today, about 30% are non-responders. Among the reasons for the high number of non-responders are underlying heart failure severity, suboptimal device programming, inadequate viable myocardium, lack of baseline dyssynchrony, and LV lead position. Positioning of the LV lead is not based on individual patient data, but on data from retrospective studies. This means that there is a potential for improving positioning of the LV lead if it is possible to asses quality of placement acutely when the leads are implanted. Among the candidates for assessing quality of LV contraction is electrical bioimpedance measurements.

Electric bioimpedance (EB) is a measure of how different tissues are impeding an electric current in a volume conductor — in this case the heart and thorax region. The measured impedance is a function of the electrical properties of tissues and blood as well as a function of the geometry of tissues and electrode placements. This work has been aimed at enabling EB research in cardiology on human subjects, and in particular by using the CRT lead electrodes after the leads are placed, but before the CRT device is connected to the leads. Work has been done to develop and build necessary equipment, and to understand the influencers on measured impedance. Furthermore, a number of measurements have been done to gain experience of what we can expect. We have also presented a method of capture detection for CRT devices based on morphology changes in EB signals.

Fred-Johan Pettersen has a background from microelectronics and physics.

Included papers:

Paper I: F. J. Pettersen, H. Ferdous, H. Kalvøy, Ø. G. Martinsen, and J. O. Høgetveit

Comparison of four different FIM configurations—a simulation study
Physiological Measurement. 35 (6) (2014) 1067-1082.

Paper II: F. J. Pettersen, and J. Høgetveit
Optically isolated current source
Journal of Electrical Bioimpedance. 6 (2015) 18-21.

Paper III: F.J.Pettersen,Ø.G.Martinsen,J.O.Høgetveit,H.Kalvøy,and H.H.Odland,
Bioimpedance measurements of temporal changes in beating hearts
Biomedical Physics & Engineering Express. 2 (2016) 065015.

Paper IV: F. J. Pettersen, Ø. G. Martinsen, L. O. Gammelsrud, E. Kongsgård, and H. H. Odland
Use of bioimpedance measurements to verify capture with biventricular pacing
Submitted to Europace on 14/08/2017.

Heart SFI