Coronary heart disease

Coronary heart disease is the disease caused by the presence of atherosclerosis in the coronary arteries. Atherosclerosis is the accumulation of lipids and inflammatory cells in the blood walls, a slow and silent process that leads to narrowing of the vessels and potential oxygen deprivation of the tissues. It is the main cause of ischemic heart disease and can lead to myocardial infarction.

Coronary heart disease is responsible for up to one third of deaths in people over 40 years of age in developed countries. Furthermore, it is estimated that half of men and one third of women will suffer some manifestation of heart disease in these regions during their lifetime. It is therefore a major global health problem.

In addition to genetic risk factors, whose contribution appears to be important, there are also non-genetic risk factors that can markedly increase the likelihood of CHD. Among them:

  • Aging increases the risk of damage to the arteries.
  • Due to the protective factor of estrogen, men are more at risk of heart disease than women. However, after menopause the risk is equalized.
  • Smoking and passive exposure to tobacco smoke.
  • Uncontrolled arterial hypertension.
  • High blood cholesterol levels. Hypercholesterolemia can lead to the formation of atheroma plaques in the blood vessels with the consequent narrowing of the same.
  • Diabetes.
  • Overweight and obesity.
  • Sedentary lifestyle.
  • Stress.
  • Unhealthy diet. High consumption of saturated fats and sugar can increase the risk of coronary heart disease.

In addition, although to a lesser extent, there are other risk factors such as having an autoimmune disease, such as rheumatoid arthritis or lupus, which can increase the risk of atherosclerosis.

Coronary heart disease is a disease of complex etiology, resulting from the interaction of lifestyle and underlying genetics. In investigating the role of genetics, GWAS studies have played a key role. In the largest to date, involving almost 35,000 patients and some 300,000 controls, 179 susceptibility loci were identified. Among the genes found, several involved in lipid metabolism, such as APOE or PCSK9, and CDKN2B, which in previous studies was strongly associated with heart disease, stand out. These findings open up new possibilities for improving quantitative measures of genetic risk that allow a better approach to the prevention of coronary heart disease.

Symptoms

It is a heterogeneous condition whose symptoms vary from person to person, ranging from no symptoms at all to severe, life-threatening symptoms.

Most commonly, in the early stages, narrowing of the arteries due to the presence of atheromatous plaques does not cause any symptoms. However, as plaque continues to build up, the following signs and symptoms may occur:

  • Sharp chest pain. This is known as "angina" and is a sudden pain that usually occurs in the middle or left side of the chest. It may feel like tightness. It may be triggered by physical or emotional stress and usually goes away within minutes.
  • Shortness of breath. If the heart cannot pump blood efficiently enough, shortness of breath or fatigue may develop.
  • Heart attack. This is the most severe sign caused by a coronary artery in which blood flow is completely interrupted. In this case, it is common to feel severe tightness in the chest, pain in the shoulder or arm and/or shortness of breath and sweating.

Prevention

Because of the important contribution of environmental factors in the development of coronary heart disease, there are actions that can be taken to effectively reduce the risk of coronary heart disease. Among them:

  • Blood pressure control.
  • Keep cholesterol and triglyceride levels low.
  • Maintaining a healthy weight.
  • Healthy diet, avoiding the consumption of ultra-processed foods rich in fats and sugars.
  • Regular physical exercise.
  • Avoiding tobacco smoke.
  • Stress control.
  • Controlling blood sugar levels and keeping diabetes under control, if present.

Number of observed variants

13.5 million variants

Number of risk loci analyzed in the study

176 loci

Bibliography

van der Harst P, Verweij N. Identification of 64 Novel Genetic Loci Provides an Expanded View on the Genetic Architecture of Coronary Artery Disease. Circulation Research. 2018 Feb;122(3):433-443.

Ozaki K, Tanaka T. Molecular genetics of coronary artery disease. J Hum Genet. 2016 Jan;61(1):71-7.

Mayo Clinic [March 2022]

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