Heart Disease NOTES - CRACK NEET by Dr. Sheth For Lecture videos on Heart Disease https://www.youtube.com/watch?v=jogIOV5w7bk&t=53s

1. Diseases of
HEART & CIRCULATION

2. DISORDER OF CIRCULATORY SYSTEM and HEART DISEASES
- Coronary Artery Disease (CAD) or Atherosclerosis (AS) / Atheroma
-Thrombus / Thrombosis
- Embolus
- Ischemia
- Infarction
- Angina Pectoris
- Heart Attack
- Silent Heart Attack
- Heart Failure
- Arteiosclerosis
- Aneurysm
- Congenital Heart Disease
- Heart murmurs
- High Blood pressure / Hypertension
- Oedema (Puffiness):
CRACK NEET with Dr. Sheth

3. 1. Coronary Artery Disease (CAD) or Atherosclerosis (AS) /
Atheroma :
Tunica Externa
Tunica Intima
Atherosclerotic
Plaque
Tunica Media
Atherosclerotic
Plaque
Tunica Media
Lumen of Artery
Mechanism and Pathology of
AS
-Platelets aggregate & release PDGF (platelet derived growth factor) in response to daily wear & tear (micro-
injuries),
for tissue repair) at site of damage
-Cholesterol & LDL also gets deposited (for cell membrane repair)
DISORDER OF CIRCULATORY SYSTEM and HEART DISEASES CRACK NEET with Dr. Sheth
CAD gradually increases with / due to Age, Stress, Obesity, HT, Diabetis,
Smoking, etc
CAD refers to the excess deposition of fibro-fatty substances, especially
cholesterol and triglycerides in the tunica interna & media of arteries.
-Such deposits form atherosclerotic plaque (ASPs) / Atheroma in arteries,
esp Coronary Arteries of the Heart
-ASPs grow into the lumen of the artery, causing narrowing & decrease in
blood flow. In extreme cases these plaques may block the artery completely
.
- AS begins from young age (even birth)
- AS & ASPs are common in Coronary arteries due to excess turbulance of
blood (d/t constant beating of heart)
-Injuries begin with intimal/endothelial damage (may extend to Tumica Intima/
smooth muscle) of the artery

4. CAD / Atherosclerosis / Atheroma
Mechanism continued ….
DISORDER OF CIRCULATORY SYSTEM and HEART DISEASES CRACK NEET with Dr. Sheth
-In some people, endothelial damage / body’s repairing responses are abnormally excessive
-so, cholesterol & other tissue / smooth muscles proliferation increases too much
-This accumulation of substances encroaches on lumen of artery to form an Atheromatous plaque/
Atheroma (see figure)
-This causes a blockage of the coronary arteries
-Thus plaque reduces the blood supply to the heart (ischemia ) or may completely stop the blood supply due
to complete
Effects of CAD (on heart) :
- Above developments are labelled collectively as CAD-Coronary artery
disease.
- CAD is seen more in people with stress, obesity, HT, Tobacco
smoking,
High Cholesterol, High LDL,
low HDL
N.P. : similar effects happen on brain, kidneys, retina, etc
also)
Thrombus Embolus Ischaemia, Infarction,
Angina pectoris, Heart Failure, Heart
Attacks

5. DISORDER OF CIRCULATORY SYSTEM and HEART DISEASES
Thrombus / Thrombosis :
It is the formation of a blood clot (thrombus) within a blood vessel
-it often happens at site of AS / ASPs
-It decrease / prevents blood normal blood flow through the circulatory system (causing ischemia / infarction)
-it can cause a heart attack
Embolus (plural emboli):
Ischaemia (pronounced as “ is-keemia”):
CRACK NEET with Dr. Sheth
-It is unattached / detached mass from a thrombus that travels through the
bloodstream and can clog / block arteries at a site distant from its point of origin.
- Thrombi and emboli are common causes of Heart Attacks
It is inadequate flow of blood to an organ / part of the heart caused by
obstruction to its blood supply (usually due to coronary artery spasm
Usually on top of CAD viz AS).
This can temporarily disturb function and efficiency (d/t tissue hypoxia)
+ cause pain (angina pectoris)
Infarction
Infarction implies death or necrosis of cells due to total obstruction of the blood
supply to an organ or region of tissue, typically by a thrombus or embolus
(superimposed on CAD plaques)

6. DISORDER OF CIRCULATORY SYSTEM and HEART DISEASES
Heart Attack
CRACK NEET with Dr. Sheth
Angina Pectoris (angina=pain, pectoris = chest)
It is the medical term for chest pain or discomfort due to coronary heart disease (Ischemia / infarction).
It occurs when the heart muscle doesn't get as much blood as it needs (coronary ischemia / infarction)
which causes cellular HYPOXIA & release of painful toxins by cardiac cells (anaerobic metabolism).
-Typically angina is a warning that person has CAD.
-Angina pectoris worsens on extertion (because increased demands worsens ischemia)
-A heart attack is any sudden/accidental dysfunction of the heart
-Commonest cause of heart attack is sudden decrease (ischemia) / stoppage of blood flow
to a portion of the heart causing necrosis / cell death (infarction) in a portion or segment of
the heart .
-Heart attacks more commonly happen due to sudden compromise in blood supply due to
1. coronary artery spasms (due to stress / anxiety/ anger / exertion)
2. Thrombus / embolus formation at / near site of CAD /AS /ASPs
Heart Attacks happen more commonly in persons whose Coronary Arterial Blood flow
is already compromised due to CAD /AS /ASPs

7. Heart Failure
Silent Heart Attack
DISORDER OF CIRCULATORY SYSTEM and HEART
DISEASES
CRACK NEET with Dr.
ShethDoes a Heart Attack Awlays Kill ??
- This implies an heart attack without pain / much discomfort (unnoticed)
- That is, the patient does not realize that he has / had got a heart attack
- 20-30 % of heart attacks are silent (no pain)
Why silent ?
Endocardium / Myocardium has no pain receptors – hence, if ischemia / infarction happens in these tissues,
then there is no pain (so attack may go unnoticed)
However, if necrotic toxins from damaged heart cells reach epicardium (part of pericardium), then pain will be sensed
N.P. : Severe diabetics often get silent heart attacks (due to peripheral Neuropathy)
It implies inability of the heart to supply adequate blood to different parts of the body .
-This happens due to sudden, acute or chronic cardiac dysfunction
Multiple reasons can cause heart failure (see below)
Viz – Heart attack, CAD, Infections of heart / pericardium , severe HT, etc
N.P. : Patient with a failing heart may not mean death ; but difficulty in performing daily chores or
exertion
-No – 40 -70 % of patients usually survive the 1st Heart Attack
especially if the patient receives timely Emergency Medical Care

8. Arteiosclerosis (sclerosis = hardening).
Aneurysm
Congenital Heart Disease (CHD):
DISORDER OF CIRCULATORY SYSTEM and HEART
DISEASES
CRACK NEET with Dr.
Sheth
-Hardening and loss of elasticity of the arteries is called arteriosclerosis.
-In arteriosclerosis, calcium salts precipitate with the cholesterol which forms plaques.
- calcification of the plaques, makes the walls of the arteries stiff and rigid / non elastic.
-so they become more prone to rupture / aneurysms
-It is an abnormal widening or ballooning of portion of an artery due to weakness in the wall of blood vessels.
-An aneurysm can ruture and cause bleeding .
-It commonly happens in arteriosclerotic arteries
Defect or diseases of the heart from birth is known as congenital heart disease
-CHDs are due to some error in the development of the heart
Causes : genetic infections chromosomal abnormalities.
Eg
PFO : Patent foramen ovale (even in adult hood)
PDA – Patent ductus arteriosus
VSD – Ventricular septal defect
N.P : Above diseases cause mixing of blood (Due to a ‘Hole in the Heart’ ; hence person is usually partially

9. Oedema (Puffiness):
DISORDER OF CIRCULATORY SYSTEM and HEART DISEASES CRACK NEET with Dr. Sheth
Fluid accumulation in the tissues resulting in a local / generalized swelling of the tissues and body is called oedema.
Causes
-lymph capillaries fail to return lymph to the blood,
- Low BCOP - Blood Colloidal Osmotic pressure (due to low albumin levels- Liver disease / Kwashiorkar, etc)
- Congestive Cardiac Failure (seeping of fluids to tissues due to high pressure in Veins)
Heart Murmurs :
These are abnormal sounds from the heart heard through the sthetoscope.
-They are usually due to abnormalities of valves due to causes like CHD, Infection, ect

10. High Blood pressure / Hypertension (HT) :
DISORDER OF CIRCULATORY SYSTEM and HEART DISEASES CRACK NEET with Dr. Sheth
Blood Pressure :
- This pressure / tension is generated by
-the pumping action of the heart heart
-the elasticity of the blood vessels (esp. the arteries)
-Sphygno-manometer : instrument to measure blood pressure.
-Normal blood pressure at rest is 120/80 mm Hg
i.e. 120 mm Hg (Systolic)/ 80 mm Hg. (diastolic) mm Hg on an average.
Hypertension : it is a chronic medical condition in which blood pressure in the arteries is elevated beyond
normal .
(>140 / 100 mmHg)Causes of High BP -
-Life style / Diet – eg High salt intake, Mental stress, Obesity, high cholesterol, tobacco,
-Renal Diseases, etc.
Effects of / Complications due to Hypertension
HT leads to heart diseases and diseases of brain, retina & kidneys.
-It is the pressure / tension exerted by the circulating blood on the walls of blood vessels, esp., the arteries