Материал: Глебова Е.И. - Английский язык для медицинских специалистов, 2012

middle layer and is the actual contracting muscle of the heart. The endocardium is the innermost layer and lines the inner chambers and heart valves.

There are four chambers in the heart: the right atrium, the right ventricle, the left atrium, and the left ventricle. The right atrium receives deoxygenated blood from the body via the superior and inferior vena cava. The right ventricle receives the blood from the right atrium and pumps it to the lungs via the pulmonary artery. The left atrium receives oxygenated blood from the lungs via four pulmonary veins. The left ventricle is the largest and the most muscular chamber; it receives oxygenated blood from the lungs via the left atrium and pumps blood into the systemic circulation via the aorta.

There are four valves in the heart. The atrioventricular valves lie between the atria and the ventricles. The bicuspid or mitral valve is located on the left side of the heart. The tricuspid valve is located on the right side of the heart. The pulmonic semilunar valve lies between the right ventricle and the pulmonary artery. The aortic semilunar valve lies between the left ventricle and the aorta.

The conductive system of the heart includes the sinoatrial node, the atrioventricular node, the bundle of His, and Purkinje fibers. All these structures are connected with each other consequently. The system spreads the waves of depolarization through the atria and the ventricles.

Two main heart sounds are usually heard in the fifth intercostal space at the left midclavicular line. They are called the first heart sound and the second heart sound. The first heart sound (S1) is heard as the atrioventricular valves close. The second heart sound (S2) is heard when the semilunar valves close.

The normal heart rate is 60 to 80 beats per minute. The normal blood pressure is 120/80 mm Hg. The first figure signifies the systolic blood pressure. The second figure signifies the diastolic blood pressure. The

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difference between the systolic and diastolic blood pressure is called pulse pressure and accounts for approximately 40 mm Hg. Heart rate (HR) and blood pressure (BP) are regulated by the autonomic nervous system, e.g. sympathetic and parasympathetic nervous system.

The vascular system consists of different types of vessels, such as arteries, arterioles, capillaries, venules, and veins. Arteries are vessels through which the blood passes away from the heart to various parts of the body. They convey highly oxygenated blood from the left side of the heart to the tissues. Arterioles control the blood flow from the capillaries. Capillaries allow the exchange of fluid and nutrients between the blood and the interstitial spaces. Venules receive blood from the capillary bed and move blood into the veins. Veins transport deoxygenated blood from the tissues back to the heart and lungs for oxygenation.

1.List the three layers of the heart.

2.What are the four chambers of the heart?

3.Name the heart valves and their locations.

4.Describe the systemic and pulmonic circulations of the heart.

5.What two parts does autonomic nervous system consist of?

6.What is the normal heart rate?

7.What are the parameters of normal systolic and diastolic BP?

8.List different types of vessels of the vascular system.

Task 4. Are these statements true (T) or false (F)? If the statement is false, correct the statement.

1.The myocardium is the actual contracting muscle of the heart.

2.The left atrium receives deoxygenated blood.

3.The right ventricle pumps the blood into the pulmonic circulation.

4.HR and BP are regulated by the autonomic nervous system.

5.Veins are the smallest vessels of the vascular system.

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2.Hypertension

VOCABULARY and PRONUNCIATION

Task 1. Read out.

3.to treat – treatment

to prevent – prevention

to measure – measurement to cause – cause

to complain of – complaint to elevate – elevation

to reduce – reduction

READING and SPEAKING

Task 2. Warm-up discussion.

What is hypertension? Why do you think so many people in developed contries suffer from this disease? What can we do to solve the problem?

Task 3. Read the text and answer the questions.

Hypertension is a persistent elevation of the systolic blood pressure above 140 mm Hg and the diastolic blood pressure above 90 mm Hg It can be classified as primary (or essential) and secondary. Primary hypertension indicates that no specific medical cause can be found. Secondary

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