Class 12 DISEASES OF HEART notes NEET AIIMS
DISEASES OF HEART
1. Angina pectoris – pain in the heart muscles, appearing as chest pain. It is caused due to incomplete (Angina-Pain, obstruction (usually due to spasm of the coronary artery.) (Pectoris- chest).
2. Tachycardia – Increased rate of heartbeat.
3. Bradycardia – The decreased rate of heartbeat.
4. Heart attack – When symptoms such as breathlessness, palpitations, pain in the chest, unconsciousness appear suddenly. Nitroglycerine is used for the treatment.
5. Heart block – When the heartbeat is not passed to the ventricles properly. This is the defect of the conducting system of the heart.
6. Arrhythmia – It is an irregular heartbeat.
7. Coronary thrombosis – Due to the formation of a clot in the coronary artery.
8. Atherosclerosis – thickening of the walls of blood vessels due to deposition of fat including cholesterol. Frequently causes Myocardial Ischaemia (death of tissue due to lack of blood).
9. Myocardial infarction – It is the death of a part of heart muscle following cessation of blood supply to it. It’s an acute heart attack.
10. Palpitations – Awareness of heartbeat or the feeling of having a rapid and unusually forceful heartbeat, especially if they last for several hours or recur over several days and/or cause chest pain, breathlessness or dizziness.
11. Fibrillation – Is a condition in which the heart muscle is contracting very rapidly but in an uncoordinated fashion. There is atrial and ventricular fibrillation. Ventricular fibrillation is immediately life-threatening unless it can be stopped by defibrillation. A machine called a defibrillator, which gives a DC voltage shock, is used to do this.
12. Arteriosclerosis – Hardening or loss of elasticity of arteries.
- The lowest level of glucose is present in the hepatic vein.
2. The highest level of amino acids is present in the hepatic vein.
3. The highest level of urea is in hepatic vein and the lowest is in the renal vein.
4. The largest vein in the human body is inferior vena cava.
5. The largest artery is the aorta.
6. The smallest blood vessel in the body is blood capillary.
7. The giraffe’s blood pressure may be the highest as the heart needs to pump the blood up to the brain which is at a height due to its tall neck.
8. One species of Antarctic fish is the only fish known to have white blood. It has no red pigment in its blood.
9. Frog has two pairs of lymph hearts.
10. Electric shock is given to stabilize the heart in case of arrhythmia or revive the heart in case of cardiac arrest.
11. Oedema occurs when lymph capillaries fail to return lymph to the blood and fluid accumulates in the tissue resulting in local swelling.
12. Lungfish has two auricles and one ventricle.
13. Crocodiles, alligators and Gavialis among reptiles have a four-chambered heart (two auricles and two ventricles).
14. The heart of fish is called venous heart because it receives deoxygenated blood.
15. In the human heart, auricles are called atria (sing. atrium).
16. Nereis and Amphioxus do not have hearts. Heart of prawn contains oxygenated blood.
17. Foramen of Panizzae is present in between two systemic arches (they arise from the heart) of the heart.
18. The average weight of a human heart – male 300 g, female -250 g.
19. Coronary angiography – When contrast medium dye is injected into the coronary arteries (arteries of the heart) and pictures are taken, it is known as coronary angiography. It is used to see blockages of arteries.
20. Excess calcium ions cause increased heartbeats.
21. RBCs fail to mature if there is a deficiency of vitamin B12 and folic acid.
22. Papillary muscles are found in the hearts of mammals.
23. Keber’s organs or pericardial glands discharge excretory products into the pericardial cavity from the freshwater mussel.
24. An insect larva has red blood. The larva of genus Chironomus is called ‘Blood Worm’. The red colour of this larva is due to haemoglobin, which has the power of attracting and storing oxygen and giving it off to the tissues as they require it.
25. Vasa Vasorum is a blood vessel which supplies blood to the blood vessel itself.
26. Blue Whale has the largest heart in the whole world.
27. TMT and Tread Mill Tests are used to check the effectiveness of the heart.
28. Angiology is the study of blood vascular and lymphatic systems.
29. The term bicuspid and tricuspid are used for valves of the heart and cusp of teeth.
30. Rhesus factor can be detected in the foetal blood starting in the 10th week.
31. Anti-A and Anti-B appear in the foetal blood about 4-8 months after birth. Those present at birth are acquired from maternal blood and usually disappear 2 weeks after birth.
32. Cardiac index is the minute volume per sq.m. of body surface area. Its normal volume is 3.3 lit/min/sq.m