Researchers at MHH want to study the altered lipid metabolism in patients with PPCM and find new biomarkers for diagnosis and therapy.
Want to prevent heart damage to expectant mothers by diagnosing high-risk PPCM patients more quickly: Professor Dr. Johann Bauersachs (left), private lecturer Dr. Melanie Ricke-Hoch (centre) and private lecturer Dr. Tobias Pfeffer ;Copyright: Karin Kaiser / MHH
Towards the end of pregnancy or shortly after giving birth, many women complain of shortness of breath, fatigue and swollen legs. These symptoms are not uncommon, but can indicate a frequently undetected condition: so-called peri- or postpartum cardiomyopathy (PPCM). This pregnancy-related heart failure develops in previously heart-healthy women a few weeks before, during or after childbirth. The pumping capacity of the left ventricle, which transports oxygen-rich blood through the aorta to all tissues of the body, is reduced.
Although PPCM occurs rather rarely, it is life-threatening. It is therefore important that affected women receive prompt and competent care. This is done at the Clinic for Cardiology and Angiology at Hannover Medical School (MHH), Europe's leading PPCM centre under the direction of Professor Dr Johann Bauersachs, who is also chairman of the European PPCM Committee. The disease is not only treated at the clinic, but has also been researched for more than 15 years with the help of the world's largest PPCM registry with data and biomaterials from around 300 patients. For example, the research group for Molecular Cardiology has already found out that in affected women the breastfeeding hormone prolactin is broken down into a vascular-damaging cleavage product that attacks the heart muscle cells and leads to heart failure. Treatment with the breastfeeding drug bromocriptine inhibits prolactin production and thus leads to a complete recovery of heart function in many PPCM patients.
Identify PPCM risk as early as possible
Nevertheless, the affected women have an increased risk of long-term damage to the cardiovascular system and are sometimes dependent on medication for the rest of their lives. In addition, not all patients respond well to the therapy. A small proportion of them suffer from permanent heart failure, which may even require a heart transplant or the use of an artificial heart. A team of the working group for Molecular Cardiology led by Dr Melanie Ricke-Hoch and Dr Tobias Pfeffer now wants to find out how pregnant women with an increased risk of PPCM can be identified as early as possible in order to prevent the development of heart failure or at least treat the disease in time. The researchers are focusing on fat metabolism, which could play an important role in the course of the disease. The project is funded by the German Research Foundation with more than half a million euros over three years.
Fat metabolism disturbed
"In preliminary studies, we were able to show that fat metabolism is disturbed in PPCM patients compared to healthy female relatives," says Dr. Ricke-Hoch. The researchers have demonstrated the changes using heart muscle cells from so-called induced pluripotent stem cells (iPS cells). These can be produced in the laboratory from "reprogrammed" body cells of adults - in this case from skin or blood cells of PPCM patients - and can then give rise to any cell type of the human body. These cell lines, as well as a specially developed PPCM mouse model, will now be used to elucidate the altered lipid metabolism pathway and find new biomarkers for diagnosis and therapy. One candidate could be the fatty acid arachnidonic acid, a precursor of prostaglandins and leukotrienes. These tissue hormones are involved in inflammatory processes and can be influenced via anti-rheumatic agents such as the pain medication ibuprofen. "Prostaglandins or similar substances are often used to induce labour," explains cardiologist Dr Pfeffer.
With their investigations, the researchers hope to shed more light on the disease. "PPCM can not only have different causes, it also shows different courses from spontaneous healing to severe heart damage or even death," emphasises the physician. New strategies for prevention, diagnosis and for more effective and tailored therapies are therefore the primary goal, but also to create more awareness for what is probably not such a rare disease. "PPCM is often not recognised and therefore probably occurs more frequently than assumed", says Dr Pfeffer. Cardiologically, the disease can be diagnosed quickly and unambiguously. The main difficulty in diagnosis is that most women do not find their way to the cardiologist at all or too late because the complaints are interpreted as normal pregnancy-associated complaints and no one suspects PPCM and refers them there.
Text: Kirsten Pötzke