Cardiovascular Diseases (CVDs)

Cardio vascular diseases consist of

•Hypertension

•coronary heart disease (CHD) / Atherosclerotic Heart disease (AHD) / coronary artery disease (CAD)

CHD include

1)Angina pectoris

i)stable angina

ii)unstable angina

iii)vasospastic angina

2)myocardial infarction (MI)

i)STEMI (ST elevation myocardial infarction)

ii)NSTEMI (no ST elevation myocardial infarction

In cardiovascular diseases BP play important role so

What is blood pressure (BP)?

Blood pressure is the product of cardiac output and total peripheral resistance.

BP=CO×TPR

The pressure exerted to the walls of blood vessels.

What is cardiac output (CO) ?

Cardiac output is the product of heart rate and stroke volume.

CO=HR×SV

Heart rate is regulated by sympathetic nervous system ( epinephrine and nor epinephrine) and parasympathetic nervous system (acetylcholine).

60-100 beats per minute

What is stroke volume?

Stroke volume is the product of contractility and venous return.

SV=contractility × venous return

Amount of blood come out from the ventricle with each cardiac cycle.

Any thing or any factor which is going to increase/decrease the stroke volume is also going to increase or decrease the cardiac output.

What is venous return?

Venous return is the product of blood volume and venous tone.

Venous return = blood volume × venous tone

Amount of blood which is carried back to the heart.

Greater the blood volume greater will be the venous return,  greater will be the stroke volume , greater will be the cardiac output and higher will be the blood pressure.

How blood volume is regulated?

Blood volume is regulated by fluid retention and thirst.

Blood volume = fluid retention × thirst

How fluid retention is regulated ?

Fluid retention is regulated by the activation of

•sympathetic nervous system

•Angiotensin II (AT-II)

(vasoconstriction , decrease blood flow to kidney, increase blood volume)

•Aldosterone

(retention of sodium ions)

•anti diuretic hormone (ADH)

(retain free water)

•atrial natriuretic peptide ( ANP)

Synthesize by heart

(increase sodium ion in urine)

How total peripheral resistance is regulated?

Total peripheral resistance is regulated by

1)Circulating factors

Which includes

☆Nor epinephrine

☆AT-II

2)Innervation

Which includes

☆Beta 2 receptor

☆alpha 1 receptor

☆M receptor

☆AT1aR receptors

3)Local factors

Which includes

☆nitric oxide

☆endothelin

☆prostaglandin E2

4)viscosity of blood

Blood pressure is regulated by our body through various processes

Regulation of blood pressure is achieved by two mechanisms

1)short term regulation

2)long term regulation

1)short term regulation

Short term regulation is achieved by

•changing the contractility of heart

•changing the diameter of blood vessels

•changing the rate of heart

2)long term regulation:

Long term regulation is achieved by RAAS system.

What is baroceptors?

Baroceptors:

Some receptors inside our blood vessels. These receptors are sensitive to pressure or mechanical stretch is called baroceptors.

Where the baroceptors are present?

Those are mostly present in aortic arch and carotid sinus.

These are collections of sensory neurons.

Carotid sinus is that dilated area just above the right carotid artery this carotid sinus contain collection of sensory neurons which is called baroceptors.

Similarly the baroceptors are also present at aortic arch.

Mostly present on these both but also present in low amount at artery of neck and head region. Whenever there is increase in the blood pressure this increase in blood pressure is going to stretch the walls of blood vessels,  put mechanical pressure on stretch , that stretch activate the baroceptors.

Baroceptors send signals to central nervous system. Out central nervous system sense that blood pressure is increased and is above than normal and the body has to reduce the blood pressure.

Learn more

Searching Tags

What is cardiovascular diseases

How many types of cardiovascular diseases?

What is blood pressure?

What is cardiac output?

How cardiac output is regulated?

What is stroke volume?

How stroke volume is regulated?

What is venous return?

How venous return is regulated?

How blood volume is regulated ?

How fluid retention is regulated?

How total peripheral resistance is regulated?

What is circulating factors?

What is local factors?

What is innervation ?

How blood pressure is regulated?

What is short term regulation of blood pressure?

What is long term regulation of blood pressure?

Difference between short term regulation and long term regulation?

What is baroceptors?

Where baroceptors is located?

Where baroceptors is present?