The heart, spleen and other organs also react to a heart attack
Heart attacks are a life-threatening event, but should never be considered in isolation of the heart complaints, according to the results of a recent study by scientists at MedUni Vienna. The acute heart attack forms a "systemic" disease, which has consequences for the entire organism.
So far, the explanation of the causes and consequences of a heart attack has mostly focused on damage to the heart and impaired heart function. But this consideration could go far too short. The new study results of the research team headed by Hendrik Jan Ankersmit and Michael Mildner at the Clinical Department for Thoracic Surgery at the University Clinics for Surgery and Dermatology at MedUni Vienna show that a reaction also takes place in other organs such as the liver and spleen. The researchers published their study in the specialist magazine "Oncotarget".
Monocausal approaches are not appropriate
So far, according to the scientists, "mostly with monocausal approaches, without a holistic approach, attempts to understand molecular and cellular processes after a heart attack (triggered by a circulatory disorder)." In addition, there is very little about the effects on the tissue surrounding the heart attack and other organs have been known. The study now published had shown in a large animal model relevant to humans that thousands of genes are involved in a heart attack.
Almost 9,000 genes involved in a heart attack
"The heart attack changed the expression of almost 9,000 genes in the heart, but also of 900 in the liver and around 350 in the spleen tissue within 24 hours after the infarction," the scientists report. In addition, the transcription factor Klf4 (a protein that is important for the activation of many other genes) could be assigned an important role here, the researchers continued. According to the scientists, the findings from the large animal model could also be confirmed by histological examinations on human autopsy material. The study was carried out by PhD student Matthias Zimmermann under the direction of Hendrik Jan Ankersmit and Michael Mildner.
Numerous organ systems involved
According to the researchers, the central finding of the current study is that myocardial ischemia, i.e. the heart attack, does not end at the injured heart muscle. In fact, the spectrum of the organs affected is much larger and there is much to suggest that numerous organ systems are involved in coordinating the organism's response to the infarction. "With this, we have shown that the tunnel gaze directed at the heart alone must be reconsidered in the event of a heart attack," says Zimmermann. The myocardial infarction is not isolated, but the entire organism reacts with it. For the first time, the current study describes what a myocardial infarction looks like in its entirety, which contributes enormously to the systems biology understanding of the symptoms, adds Hendrik Jan Ankersmit.
The new findings do not call into question the current acute therapy for a heart attack, but they do open up the discussion “whether a future therapy should not be viewed systemically and should start at several points in the organism”, the scientists conclude. (fp)