Aortic valve stenosis is the most common heart valve disease in older adults. The aortic valve is narrowed and the blood is no longer pumped sufficiently into the body. This often leads to shortness of breath, severe chest pain and dizziness or even unconsciousness.
Functionless connective tissue instead of muscle: "myocardial fibrosis"
In order to stabilise the cardiovascular system under additional strain, the heart muscle adapts and can undergo pathological changes: The healthy heart tissue is replaced by non-functional connective tissue and the muscle hardens. Such "myocardial fibrosis" results in chronic heart failure. Advanced aortic stenosis should therefore be treated quickly.
New aortic valve via catheter
Over the past ten years, catheter-assisted aortic valve replacement (TAVI) has become the established treatment for aortic stenosis. In this particularly gentle procedure, the calcified aortic valve is pushed aside and a new heart valve is placed in position via the inguinal artery using a catheter.
Study: Myocardial fibrosis plays an important role in further progression
Since 2017, doctors at the Heart Centre of the University Medical Centre Göttingen (UMG) have been conducting a study to investigate the influence of myocardial fibrosis on the remodelling processes of the heart and how it affects the treatment outcomes of patients with severe aortic stenosis following TAVI. For this purpose, an additional tissue sample was taken from the left ventricle of the heart of 100 study patients during the procedure. By analysing the tissue samples, the scientists found that people with more pronounced myocardial fibrosis had a much higher risk of dying from a cardiovascular-related cause later on. The pathological proliferation of connective tissue in the heart slows down the degradation processes of the heart. Nevertheless, the TAVI procedure itself also significantly improved the quality of life of patients with severe fibrosis. The results of the study were published in the renowned European Heart Journal.
Quality-assured biobanking of the tissue samples
The UMG's Central Biobank provided its entire infrastructure for biobanking the samples. The employees were responsible for processing the samples and storing them at -80°C and -190°C in liquid nitrogen. "By working with us, the researchers were able to rely on optimal treatment of the study samples," says PD Dr Sara Y. Nussbeck, Head of the Central Biobank UMG and partner in the German Biobank Network (GBN). "With our quality-assured biobanking, we create the basis for research findings."
New therapeutic approach
According to the results of the study, the condition of the heart muscle appears to play a much more important role in survival after valve replacement than previously assumed. Aortic stenosis is not just a valve disease, it is also a disease of the left ventricle. "With these results, a new therapeutic approach should be considered to improve the long-term survival of patients after TAVI. In the past, we seem to have paid too little attention to the left ventricle after TAVI. So far, there is no specific treatment for myocardial fibrosis, so anti-fibrotic medications should definitely be tested in future studies," says Prof Dr Miriam Puls, Managing Senior Physician of the Department of Cardiology and Pneumology at the UMG and first author of the study.
Source:An original version of this text appeared as a press release from the University Medical Centre Göttingen (UMG).
Picture credits: University Medical Centre Göttingen/Heart Centre
Scientific publication
Miriam Puls, Bo Eric Beuthner, Rodi Topci, Anja Vogelgesang, Annalen Bleckmann, Maren Sitte, Torben Lange, Sören Jan Backhaus, Andreas Schuster, Tim Seidler, Ingo Kutschka, Karl Toischer, Elisabeth Zeisberg, Claudius Jacobshagen, Gerd Hasenfuß: Impact of myocardial fibrosis on left ventricular remodelling, recovery, and outcome after transcatheter aortic valve implantation in different haemodynamic subtypes of severe aortic stenosis. European Heart Journal (2020), doi: 10.1093/eurheartj/ehaa033. February 12th, 2020.