Induction of arrhythmias by overpacing


Heart failure results from ventricular fatigue and remodeling.

Usually accompanied by arrythmia.

Some ventricular hypertrophy.

Decreased cardiac output associated with diminished fractional shortening and diminished end-diastolic volume and a decrease in end-systolic volume.



Implant pacemaker.

Pace the heart 24/7 for 4 weeks at 800 bpm (rats), 650 bpm (guinea-pigs).

Study outcome

Cardiac echography (ultrasound)

Biomarkers (troponins, CKMB, ANP, NT-Pro-BNP)

Invasive hemodynamics (BP, HR, ECG)



Rats, guinea-pigs

Marzena Biernat

Ph.D., Veterinarian and Histopathologist

“Microscopic image analysis has been my great passion for over 25 years. The observation of the histopathological changes taking place in the new experimental animal models and the drawing of conclusions makes me really happy. I like the smell of the knowledge in the morning and the freedom of having science in my life.” Marzena completed her Ph.D. in Factors Controlling Growth and Maturation of the Small Intestinal Structure and Function at The Kielanowski Institute of Animal Physiology and Nutrition. Postdoc studies on Hormonal Modulation of Pancreatic Secretion and Different Types of Pancreatitis at the Université de Sherbrooke. Her DVM was completed at the Warsaw University of Life Sciences.