HEALTH TOPICS A TO Z

What are cardiovascular diseases?

Cardiovascular diseases (CVDs) are a group of disorders of the heart and blood vessels and include:

• Coronary heart disease – disease of the blood vessels supplying the heart muscle
• Cerebrovascular disease - disease of the blood vessels supplying the brain
• Peripheral arterial disease – disease of blood vessels supplying the arms and legs
• Rheumatic heart disease – damage to the heart muscle and heart valves from rheumatic fever, caused by streptococcal bacteria
• Congenital heart disease - malformations of heart structure existing at birth.
• Deep vein thrombosis and pulmonary embolism – blood clots in the leg veins, which can dislodge and move to the heart and lungs.

Heart attacks and strokes are usually acute events and are mainly caused by a blockage that prevents blood from flowing to the heart or brain. The most common reason for this is a build-up of fatty deposits on the inner walls of the blood vessels that supply the heart or brain. Strokes can also be caused by bleeding from a blood vessel in the brain or from blood clots.

FACTS ABOUT CARDIOVASCULAR DISEASES

• CVDs are the number one cause of death globally: more people die annually from CVDs than from any other cause;
• An estimated 17.5 million people died from CVDs in 2005, representing 30% of all global deaths. Of these deaths, an estimated 7.6 million were due to coronary heart disease and 5.7 million were due to stroke.
• Over 80% of CVD deaths take place in low- and middle-income countries and occur almost equally in men and women;
• By 2015, almost 20 million people will die from CVDs, mainly from heart disease and stroke. These are projected to remain the single leading causes of death.

WHAT CAUSES CARDIOVASCULAR DISEASES?

• The causes of CVDs are well established and well known. The most important causes of heart disease and stroke are unhealthy diet, physical inactivity and tobacco use. These are called 'modifiable risk factors'.
• The effects of unhealthy diet and physical inactivity may show up in individuals as raised blood pressure, raised blood glucose, raised blood lipids, and overweight and obesity; these are called 'intermediate risk factors'.
• The major modifiable risk factors are responsible for about 80% of coronary heart disease and cerebrovascular disease.
• There are also a number of underlying determinants of chronic diseases, or, if you like, "the causes of the causes". These are a reflection of the major forces driving social, economic and cultural change – globalization, urbanization, and population ageing. Other determinants of CVDs are poverty and stress.

WHAT ARE COMMON SYMPTOMS OF CARDIOVASCULAR DISEASES?

• Often, there are no symptoms of the underlying disease of the blood vessels. A heart attack or stroke may be the first warning of underlying disease.
• Symptoms of a heart attack include: pain or discomfort in the centre of the chest; pain or discomfort in the arms, the left shoulder, elbows, jaw, or back. In addition the person may experience difficulty in breathing or shortness of breath; feeling sick or vomiting; feeling light-headed or faint; breaking into a cold sweat; and becoming pale.
• Women are more likely to have shortness of breath, nausea, vomiting, and back or jaw pain.
• The most common symptom of a stroke is sudden weakness of the face, arm, or leg, most often on one side of the body. Other symptoms include sudden onset of: numbness of the face, arm, or leg, especially on one side of the body; confusion, difficulty speaking or understanding speech; difficulty seeing with one or both eyes; difficulty walking, dizziness, loss of balance or coordination; severe headache with no known cause; and fainting or unconsciousness.
• People experiencing these symptoms should seek medical care immediately.

Rheumatic heart disease

Causes

• Rheumatic heart disease is damage to the heart valves and heart muscle from the inflammation and scarring caused by rheumatic fever. Rheumatic fever is caused by streptococcal bacteria, which usually begins as a sore throat or tonsillitis in children.

Symptoms

• Symptoms of rheumatic heart disease include: shortness of breath, fatigue, irregular heart beats, chest pain and fainting;
• Symptoms of rheumatic fever include: fever, pain and swelling of the joints, nausea, stomach cramps and vomiting.

Treatment

• Early treatment of streptococcal sore throat can stop the development of rheumatic fever. Regular long-term penicillin treatment can prevent repeat attacks of rheumatic fever which give rise to rheumatic heart disease and can stop disease progression in people whose heart valves are already damaged by the disease.

WHAT ARE THE ECONOMIC COSTS OF CARDIOVASCULAR DISEASES?

• CVDs affect many people in middle age, very often severely limiting the income and savings of affected individuals and their families. Lost earnings and out of pocket health care payments undermine the socioeconomic development of communities and nations.
• CVDs place a heavy burden on the economies of countries. For example, it is estimated that over the next 10 years (2006-2015), China will lose $558 billion in foregone national income due to the combination of heart disease, stroke and diabetes.
• Lower socioeconomic groups in high income countries generally have a greater prevalence of risks factors, diseases and mortality,. A similar pattern is emerging as the CVD epidemic evolves in low and middle income countries.

HOW CAN THE BURDEN OF CARDIOVASCULAR DISEASES BE REDUCED?

• At least 80% of premature deaths from heart disease and stroke could be avoided through healthy diet, regular physical activity and avoiding tobacco smoke.
• Individuals can reduce their risk of CVDs by engaging in regular physical activity, avoiding tobacco use and second-hand tobacco smoke, choosing a diet rich in fruit and vegetables and avoiding foods that are high in fat, sugar and salt, and maintaining a healthy body weight;
• Comprehensive and integrated action is the means to prevent and control CVDs:
• Comprehensive action requires combining approaches that seek to reduce the risks throughout the entire population with strategies that target individuals at high risk or with established disease;
• Examples of population-wide interventions that can be implemented to reduce CVDs include: comprehensive tobacco control policies, taxation to reduce the intake of foods that are high in fat, sugar and salt, building walking and cycle ways to increase physical activity, providing healthy school meals to children
• Integrated approaches focus on the main common risk factors for a range of chronic diseases such as CVD, diabetes and cancer: unhealthy diet, physically inactivity and tobacco use
• Effective and inexpensive medication is available to treat nearly all CVDs;
• After a heart attack or stroke, the risk of a recurrence or death can be substantially lowered with a combination of drugs – statins to lower cholesterol, drugs to lower blood pressure, and aspirin;
• Effective medical devices have been developed to treat CVDs, such as pacemakers, prosthetic valves, and patches for closing holes in the heart;
• Operations used to treat CVDs include coronary artery bypass, balloon angioplasty (where a small balloon-like device is threaded through an artery to open the blockage), valve repair and replacement, heart transplantation, and artificial heart operations;
• There is a need for increased government investment through national programmes aimed at prevention and control of CVDs and other chronic diseases.

WHO STRATEGY FOR PREVENTION AND CONTROL OF CHRONIC DISEASES

The work of the World Health Organization (WHO) on cardiovascular diseases is integrated into the overall WHO chronic disease prevention and control framework of the Department of Chronic Disease and Health Promotion. The strategic objectives of the Department are to raise awareness about the global epidemic of chronic diseases; create healthy environments, especially for poor and disadvantaged populations; slow and reverse trends in common chronic disease risk factors such as unhealthy diet and physical inactivity; and prevent premature deaths and avoidable disability due to major chronic diseases.