CARDIOVASCULAR SYSTEM

CARDIOVASCULAR SYSTEM

The Cardiovascular System

• The heart, blood vessels, and blood make up a cardiovascular system.
• The blood transports various substances like hormones and nutrients, regulates and maintains homeostasis of body fluids, and defends from blood injury through clotting also from diseases through phagocytic lymphocytes and antibodies.
• The arteries, arterioles, capillaries, venules, and veins constitute the blood vessels. Its functions are regulating the volume and speed of blood flow, providing structure for the exchange of substances, and the flow of blood to and from the heart.

 

THE HEART

• The human heart anatomy constitutes four chambers the two upper chambers known as atria and the two lower chambers are ventricles.
• The right heart is made up of right ventricles and right auricles while the left heart is made up of the left ventricle and left auricles separated by a septum.
• The heart is enclosed by the pericardium, which protects and anchors the heart in the chest. (Kroeker,2018) The fluid which is found between the inner and outer layer of the pericardium is pericardial fluid. The fluid loosens the heart during the contraction of the heart and diaphragm.
• Outer of the heart has three layers, the epicardium outer layer, the endocardium is the inner layer contracts the blood, and the myocardium which consists of contracting muscles is the middle layer.
• Atrioventricular valves are made up of tricuspid and mitral valves which connect the anterior and ventricles.

 

• Semilunar valves distinct right ventricles from the pulmonary artery while left ventricles are separated from the aorta by aortic valves.
• The heart muscles are anchored to the valves by heartstrings. Sino arterial nodes drive the heart contraction by producing electrical pulses.

 

FUNCTIONS OF THE CARDIOVASCULAR SYSTEM.

1. Propels blood throughout the body via circulatory system removing carbon dioxide and waste to the excretory organs for disposal this is known as a pulmonary circuit.
2. Oxygenated blood leaves the aorta and enters the arteries and capillaries supplying oxygen and nutrients to the tissue through the systemic circuit. (Danielewski, 2020)
3. It contains pacemaker cells that produce a heartbeat by contraction.
4. Blood components protect the body from infections and diseases and repair injured blood vessels.
5. Blood helps regulate acid-base balance, temperature, and water content of body fluid.

 

HEART PACEMAKERS

• Pacemakers are a battery-operated device that feels when the heart is beating unevenly or too slowly. It corrects the pace of the heartbeat by sending signals to the heart.
• It regulates the electrical system of the body thus controlling the heart rhythm whereby for each heartbeat an electrical impulse pass from the top to the bottom of the heart making the heart muscles contract.
• Pacemakers consist of two portions; the generator has the battery and information that controls the heartbeat and the leads are wires connecting the heart to the generator and carriers’ electrical messages to the heart.
• Pacemakers help surgeon manage arrhythmias and are of two types of tachycardia that manages a faster heartbeat and bradycardia that manages a slower heartbeat.

PACEMAKER EXPERIMENT

• The procedure utilizes a sedative to relax and feel no pain during the process. This takes about one hour in which a small cut is made on the left side of the chest.
• The pacemaker generator is implanted inside the skin and then using an x-ray, a lead wire pacemaker is implanted into the cut, vein, and into the right ventricles.
• The lead is then connected to the generator and stitches used to close the cut. https://www.britannica.com/science/human-cardiovascular-system
• The pacemakers used for medical emergencies are transcutaneous and transvenous pacemakers which are temporary. https://backyardbrains.com/experiments/heartrate
• The test for correct pacemaker results is; echocardiogram that measures the size and thickness of heart muscles using sound waves, a stress test that determines heart rate while excising, electrocardiogram that measures the heart’s electrical signals and Holter monitor that detects heart rhythm for 24 hours.
• Complications associated with the pacemaker are bleeding, collapsed lung, bruising, punctured heart, infection at the site of the cut, damaged nerves, and blood vessels and allergic reactions.

 

CARDIOVASCULAR SYSTEM EXPERMIEMENT

• The measure of the blood pressure using sphygmomanometer to understand how the
• heart rate, total peripherical resistance, and stroke volume are related to exercise.
• Expected results are that during exercise the heart rate increases dramatically, this is because during exercise the muscles need extra oxygen and thus the hearts beat more times and make for quicker pulse thus increased heart rate.
• The heart pressure is lowered due to exercise makes the heart stronger hence strong heart pumps blood with less effort.
• During exercise the total resistance decreases and the cardiac output increases, pulse pressure increases due to increased stroke volume.

 

DISEASES OF CARDIOVASCULAR SYSTEM

1. Coronary heart disease

The disease is associated with the formation of a plaque that hardens the arteries thus reducing oxygen supply. the hardening id is known as arteriosclerosis.

2.Pulmonary embolism and deep vein embolism

This is the development of a blood clot in the leg which can be disrupted and travel to the lungs hence blocking the blood flow this condition is called pulmonary embolism.

 

3.Heart failure

This condition means that the heart is not pumping blood strongly as it should. The condition can lead to shortness of breath and swelling because the disease causes the body to hold salt and water.

4.Cardiomyopathies

It is known as the disease of the heart muscle and is caused by the heart enlargement. the heart cannot pump blood as it should. People with the condition usually have their heart’s large and thick. Cardiomyopathy may be passed on in the family. Diabetes, high blood pressure, obesity, and metabolic diseases are the major cause of the condition.

5.Congenital heart disease

The condition is associated with a defect in parts of the heart or blood vessel.it usually happens before birth .it is caused by genes or when the infant is exposed to viral infections, drugs, alcohol before birth.

6.Heart valve disease

Valves keep blood flowing in the heart. (Van Rosendael,2018) When there is a problem with the valves the following conditions might arise:

Aortic stenosis: in this case, the aortic valves narrow and reduces the blood flow from the heart to the rest of the body.

Mitral valve insufficiency: the condition is caused by mitral valves not closing tightly hence the blood leaks reverse leading to a fluid holdup in the lungs.

Mitral valve prolapses: this disease is caused by valves between the left upper and left lower chamber does not close right.

7.Rheumatic heart disease

This is an inflammatory disease that Is caused by a rheumatic fever which causes the damage of heart valves. It mostly occurs in children. The disease starts with an untreated strep throat and later affects the child in many parts of the body.

8.Pericarditis

This condition is rare and is usually caused by lining surrounding the heart become inflamed. The disease is caused by an infection.

9.Stroke

A stroke occurs when there is blockage of blood to the brain thus the brain cannot get oxygen and nutrients causing the brain cell to die

 

 

Reference

Danielewski, M., Matuszewska, A., Nowak, B., Kucharska, A. Z., & Sozański, T. (2020). The Effects of Natural Iridoids and Anthocyanins on Selected Parameters of Liver and Cardiovascular System Functions. Oxidative Medicine and Cellular Longevity, 2020.

Experiment: Heart Action Potentials. (2020). Retrieved 4 May 2020, from https://backyardbrains.com/experiments/heartrate

human cardiovascular system | Description, Anatomy, & Function. (2020). Retrieved 4 May 2020, from https://www.britannica.com/science/human-cardiovascular-system

Jacobson, P. M. (2016). U.S. Patent No. 9,358,400. Washington, DC: U.S. Patent and Trademark Office.

Kroeker, C. G. (2018). Cardiovascular System: Anatomy and Physiology. Cardiovascular Mechanics, 1-17.

Van Rosendael, P. J., Delgado, V., & Bax, J. J. (2018). Pacemaker implantation rate after transcatheter aortic valve implantation with early and new-generation devices: a systematic review. European heart journal, 39(21), 2003-2013.