Medical Bulletin 22/July/2023

Overview

Here are the top medical news for the day:

Latest AHA and ACC guideline for treating chronic heart disease

Chronic coronary disease (CCD) is an umbrella term used to describe a variety of long-term vascular and heart conditions in which there is inadequate blood flow to or from the heart. It applies to people with chronic, heart-related chest pain; people who have had a heart attack, coronary stent or bypass surgery; and people who have evidence of reduced blood flow to the heart based on diagnostic testing.

The latest joint guideline for chronic coronary disease from the American Heart Association and the American College of Cardiology, affirms the value of a healthy diet, regular physical activity and not smoking, and updates several medication recommendations, including the use of SGLT-2 inhibitors, GLP-1 receptor agonists beta blockers, and bempedoic acid and inclisiran, according to the most recent scientific data..

Ref: American College of Cardiology Joint Committee on Clinical Practice Guidelines

Sleep disturbance cause in cardiac disease identified

Around on third of people with heart disease suffer from sleep problems. In a paper published in the journal Science, a team at the Technical University of Munich (TUM) shows that heart diseases affect the production of the sleep hormone melatonin in the pineal gland. The link between the two organs is a ganglion in the neck region. The study demonstrates a previously unknown role of ganglia and points to possible treatments.

The team discovered that macrophages accumulate in the cervical ganglion of mice with heart disease. These macrophages cause inflammation and scarring in the ganglion and the destruction of nerve cells. In mice, as in humans, long fibers extending from these nerve cells, called axons, lead to the pineal gland. At advanced stages of disease, there was a substantial decrease in the number of axons connecting the gland to the nervous system. There was less melatonin in the bodies of the animals and their day/night rhythm was disrupted.

Ref: K.A. Ziegler, A. Ahles, A. Dueck, D. Esfandyari, P. Pichler, K. Weber, S. Kotschi, A. Bartelt, I. Sinicina, M. Graw, H. Leonhardt, L. Weckbach, S. Massberg, M. Schifferer, M. Simons, L. Hoeher, J. Luo, A. Ertürk, G.G. Schiattarella, Y. Sassi, T. Misgeld, S. Engelhardt. “Immune-mediated denervation of the pineal gland underlies sleep disturbance in cardiac disease”. Science (2023). 

Mitochondrial proteins protect heart cells from chemotherapy damage

Researchers at the University of Illinois Chicago have identified a process by which enzymes can help prevent heart damage in chemotherapy patients. The enzymes are normally found in a cell’s mitochondria. But when heart cells are put under stress from certain types of chemotherapy drugs, the enzymes move into the cell’s nucleus, where they are able to keep the cells alive.

First the team discovered that when the heart cells were stressed by chemotherapy, the mitochondrial enzymes moved into the cell’s nucleus — an unusual phenomenon. But they didn’t know if that movement was the cause of the cell’s damage or the means of its protection, explained Dr. Jalees Rehman, co-senior author.

Ref: Nuclear translocation of mitochondrial dehydrogenases as an adaptive cardioprotective mechanism, Nature Communications