Public defence: Marianne Inngjerdingen Forså

Cand.med. Marianne Inngjerdingen Forså at Institute of Clinical Medicine will be defending the thesis “The growing heart – from normal to pathology. Impact of exercise and genetics” for the degree of PhD (Philosophiae Doctor).

Bildet kan inneholde: skjorte, smil, hår, øyenbryn, lykke.

Photo: Åsne Rambøl Hillestad, UiO

Due to copyright issues, an electronic copy of the thesis must be ordered from the faculty. For the faculty to have time to process the order, the order must be received by the faculty at the latest 2 days before the public defence. Orders received later than 2 days before the defence will not be processed. After the public defence, please address any inquiries regarding the thesis to the candidate.

Trial Lecture – time and place

See Trial Lecture.

Adjudication committee

  • First opponent: Senior Researcher Stefano Caselli, Hirslanden-Klinik im Park, Zurich, Zwitserland
  • Second opponent: Professor Maja-Lisa Løchen, UiT The Arctic University of Norway
  • Third member and chair of the evaluation committee: Associate Professor Johannes Lagethon Bjørnstad, University of Oslo

Chair of the Defence

Associate Professor Lars Fjellbirkeland, University of Oslo

Principal Supervisor

Professor Thor Edvardsen, University of Oslo

Summary

Athlete’s heart is a physiological cardiac adaptation to exercise, characterized by increased wall thickness and chamber size. These changes may overlap with early signs of hypertrophic cardiomyopathy, a genetic disease associated with ventricular arrhythmias and sudden cardiac death. Distinguishing between the two conditions is crucial, yet data on paediatric athletes remain limited. Similarly, arrhythmogenic right ventricular cardiomyopathy has mainly been studied in adults, leaving paediatric patients underrepresented.

In the thesis The growing heart – from normal to pathology. Impact of exercise and genetics, Marianne Inngjerdingen Forså and co-authors investigate cardiac development in adolescent athletes and paediatric cardiomyopathy patients. The work is based on three longitudinal cohort studies.

The authors describe signs of athlete’s heart in both males and females from age 12, with increasing sex differences during adolescence. Athletes of both sexes displayed wall thickness beyond upper reference values, suggesting a potential grey zone of left ventricular hypertrophy. Compared with age- and sex-matched genotype-positive hypertrophic cardiomyopathy patients, the athletes showed symmetrical cardiac growth and relative normalization of wall thickness as body size increased. In contrast, genotype-positive hypertrophic cardiomyopathy patients showed increasingly asymmetrical wall thickness. Two cases of cardiac arrest occurred after rapid disease progression.

The thesis further examines arrhythmogenic right ventricular cardiomyopathy in children and adolescents. Previous guidelines recommended cardiac evaluation of genotype-positive children from age 10–12 years. Forså and co-authors found high disease penetrance and a malignant phenotype before age 12, with progression to heart failure in early-onset disease. Arrhythmias were more frequent in adolescence. The thesis highlights the limitations of extrapolating findings from adults to paediatric populations.

Additional information

Contact the research support staff.

Published May 29, 2026 8:33 AM - Last modified June 10, 2026 3:01 PM