High cholesterol levels may increase risk of this major heart valve disease

In a new study, researchers have found that while having high cholesterol levels does not influence your risk of aortic or mitral valve regurgitation, it does increase your risk of developing another major heart valve disease—aortic stenosis.

The research was conducted by a team from The George Institute for Global Health at the University of Oxford.

Aortic stenosis is the narrowing of the aortic valve, the ‘door’ between the main pumping chamber of the heart—the left ventricle—and the body’s main blood vessel—the aorta.

It is the most common form of heart valve disease in developed countries and is thought to affect 2-7% of those over the age of 65.

Affected patients commonly experience symptoms such as chest pain, shortness of breath, heart palpitations and, in more severe cases, collapse and loss of consciousness.

The study team used a state-of-the-art method called Mendelian randomization to determine the causal effect.

At fertilization (the union of a human egg and sperm cell), we are all randomly allocated genes that are known to be associated with health-related characteristics in later life; in this case either normal or high cholesterol levels.

The researchers were, therefore, able to categorize the study population by genetically-determined cholesterol level and then directly compare outcomes in terms of onset of aortic stenosis.

They found that having high levels of ‘bad’ LDL cholesterol in the bloodstream for a prolonged amount of time could increase the risk of developing the condition, putting extra strain on the heart to pump blood around the whole body.

These management options are linked to strong complications and procedural costs estimated at £10,000 for valve replacement surgery and £16,000 for catheter intervention in the UK.

Crucially, the evidence that high cholesterol is a risk factor for aortic stenosis presents clinicians with an opportunity to modify disease risk via preventative measures, for instance through the use of cholesterol-lowering medications such as statin therapy.

The lead author of the study is Milad Nazarzadeh.

The study is published in the European Heart Journal.

Copyright © 2020 Knowridge Science Report. All rights reserved.