Thomsen Group - Cardiac Electrophysiology 

A broad armamentarium of approaches is key to solving tomorrow’s research questions. In this lab, we take pride in being integrative experimental physiologists, who can draw advantage from many different disciplines, like in-vivo, ex-vivo and cellular electrophysiology, molecular biology, protein chemistry, surgery and pharmacology, to lift and join findings to reach a higher level of understanding.

Recordings of electrocardiograms (ECG) from a range of mammals

The surface ECG is central to cardiac electrophysiology. We record high-resolution ECGs with minimal noise. Our laboratory is designed to reduce ambient electrical noise, including electrical shielding in the walls. The ECG gives us important information about the global (i.e., whole heart) electrophysiology and can be obtained from any animal, from mice to elephants. And we have done just that.

Radiotelemetry recordings from conscious mice

We surgically place small radiotransitters in mice or rats and after recovery, we can record a ECG and/or blood pressure under conscious conditions. In our telemetry lab, the animals are placed in their home cage on receivers and the signal is recorded continuously. We often record for several days under controlled light/dark cycles.

Echocardiographic examination of cardiac structure and function

Advanced imaging of the beating heart inside the animal is a key physiological technique to assess both cardiac structure and pumping function. By using non-invasive ultrasound examinations, we can also describe structural and functional remodeling over a period of time using the individual animal as its own control.

Isolated heart studies

Isolated heart preparations are useful to study the properties of the heart without the influence of the physiological feedback from the remaining organ systems, e.g., the vasculature or the autonomic nervous system.

We have a state-of-the-art setup for studying isolated mouse hearts using either the Langendorff principle or the working heart principle. We record ECG, coronary flow and ventricular pressure in this setup. Via programmed electrical pacing, we can control heart rate. By controlling preload and afterload, we can study cardiac pump function.

Calcium imaging

We use fluorescent dyes to gauge intracellular calcium fluxes in disaggregated cardiomyocytes. By measuring the release and removal of cytosolic calcium on a beat-to-beat basis, we can study the mechanisms behind pump function, contraction and relaxation, on a cellular basis.

Intracardiac pacing to induce cardiac arrhythmias

It is possible to pace the heart from within and thereby control heart rate or to test vulnerability to arrhythmias. We often do this with anesthetized mice. We enter either the right atria and ventricle from the right external jugular vein or the left ventricle from the left common carotid artery. When the catheter is placed correctly, we can record local cardiac activity and pace the heart from the electrodes at the tip of the catheter.

Invasive blood pressure recordings

To understand the hemodynamic consequences of cardiac disease, we record blood pressure invasively, either in the carotid artery or in the left ventricle. We also have the option to record blood volume simultaneously with blood pressure in the left ventricle of the anesthetized mouse. This provides unique integrated information about the systolic and diastolic properties of the beating heart in the mouse.

Scientific publishing is not only important; it is also an enjoyable aspect of research. Peer review is central to scientific publishing and it should be done well. I believe that every scientist should review >3 manuscript for every paper he or she publishes.

I am and have been on the editorial board of several scientific journals. I only work with journals owned by a scientific society, because the journals support the society and vice versa. For-profit journals only support the stockholders. For this reason, I am happy to review free for society-owned scientific journals; however, I do require an honorarium (currently USD 450 per manuscript) for reviewing for for-profit journals.

I believe scientific reviewing should be acknowledged, as are publications and attracted funding. I use Web of Science to keep track of my reviewing activities and link to this from my CV. You can see my reviewer profile here.

I arrange PhD-student masterclasses on How to review and What happens once you've submitted your manuscript.

Over the years, the lab has received funding from (in alphabetical order):

Aase og Ejnar Danielsen Foundation

Arvid Nilsson Foundation

Beckett Foundation

C.C. Klestrup og Hustru Henriette Klestrup Foundation

Carlsberg Foundation

Danish Agency for Science, Technology and Innovation, Medical Research Council

Foundation Juchum

Hede Nielsen Foundation

Innovation Fund Denmark

Snedkermester Sophus Jacobsen og Hustru Astrid Jacobsen Foundation

The Heart Rhythm Society

The Novo Nordisk Foundation

Vissing Foundation