regulation of cardiac activity is given in brief along with the cardiac diseases. For diseases, just pictures are added you need to go through the explanation separately so that pictures will make you to explain it easily.

1. JNANA SAHYADRI, SHANKARAGHATTA

3. Heart is a wonderful organ made up
of specialized muscles called as
cardiac muscles which is involuntary
in function.
Since it is auto-regulated by
specialized muscle cells, it is called as
“MYOGENIC”
The main function of the heart is to
pump the blood to various parts of the
body.
Cardiac cycle helps in the
circulation of blood throughout the
body.

4. Cardiac cycle
Systolic
phase
Contraction of
cardiac muscles
Diastolic phase
Relaxation of
cardiac muscles

5. REGULATION OF CARDIAC ACTIVITY
Intrinsic
Regulation
Extrinsic
Regulation
Neural
regulation
Hormonal
Regulation

7. SA-NODE
AV-NODE
AV-Node to bundle of
His
left & right bundle
branches
Purkinje fibers to
ventricular muscles

10.  Carried out by the ANS ( Autonomic Nervous System).
 Includes sympathetic and parasympathetic nerve regulation.
 The cardiac reflex centre baroreceptors & chemoreceptor responds to
various signals from cerebral hemispheres.
 The cardiovascular control centre also plays an very important role in
regulating the cardiac activity which is located at the ventro-lateral
medulla.
 The sympathetic components leads to TACHYCARDIA by releasing the
cardio-accelerators. E.g.: catecholamine
 The parasympathetic component leads to BRADYCARDIA by releasing the
cardio-inhibitors. E.g.: acetylcholine
 CNS also plays a very important role in regulation of heartbeat. CNS
sends an impulse through the cardiovascular centre in the medulla. There
is a co-ordinate and quick response of both the heart and the blood
vessels to change blood pressure, tissue perfusions to respond to the
requirements.
 Therefore both sympathetic and parasympathetic nerves works together
to regulate the heart rate.

12. Catecholamine
Endothelins
Aldosterones
Antidiuretic hormones
Thyroxin

13. Natriuretic peptides
Neurokinin-A
Oxytocin
Acetylcholine

16.  Digitalis – increases strength of heart muscles and
accelerates heart rate. This drug is used for low B.P but very
high concentration can stop heart beat.
 Atropin- which is a stimulatory drug which results in
Tachycardia by supressing acetylcholine, hence used as
antidote against toxic effect of many poisonous substances.
 β-blockers like inderal,propandarol,Muscarin, eserine,
pilocarpine cause Bradycardia by mimicking acetylcholine.
 Pulmonary bronchiodialators like isoproterenol, ephedrine
cause Tachycardia.
 Drugs that acts as stimulants such as caffeine, nicotine,
cocaine also results in Tachycardia.

17. BLOOD SUGAR LEVEL
EMOTIONAL STRESS .
LACK OF SLEEP
STRESS
ANGER
FEAR, etc.
These factors also determines the increase
or decrease of heart rate

25. CVDs can be detected by the
following ways
Echocardiogram
Stress test
Holter monitor
Cardiac CT
Chest X-Ray
Cardiac
cathetrization

27. BY MEDICATION
By Aspirin or anticoagulants or
blood thinners.
By some of the drugs which lowers
the cholesterol level, high blood
pressure.
Other medications include
vasodilators, β-blockers, Calcium ion
channel blockers, etc.

28. BYPASS SURGERY

32. Heart is a wonderful organ made up of specialized
muscle cells called as cardiac muscles. These are
involuntary in function hence it is “Myogenic”.
 Cardiac cycle helps in the circulation of blood
throughout the body. This cardiac cycle can be
regulated by 2 main mechanisms. They are:
 Intrinsic regulation of cardiac activity
 Extrinsic regulation of cardiac activity
a) Autonomic regulation of cardiac activity
b) Hormonal regulation of cardiac activity
 Intrinsic regulation of heart rate involves SA-node, AV-
node, bundle of his, purkinje fibers. SA-node generates
impulse by itself and makes the cardiac cycle.

33.  Extrinsic regulation is further divided into 2 types i.e.,
neural regulation involves sympathetic and asympathetic
nerves regulates the heartbeat. Whereas in hormonal
regulation, hormones like catecholamine, acetylcholine
regulates the heart rate.
 Other factors like environment stress, drugs also regulate
the heartbeat.
 Cardio-vascular system is not only associated with
circulation of blood, but also with certain CVDs like, heart
attack, hypertension, cardiomypathy, congenital heart
disease, AFib, Arrhythmia, high blood pressure, etc.
 Treatment involves medication with drugs, surgery,
angioplasty, etc
 Since prevention is better than cure, we have to take care
of our heart by following healthy lifestyle.

34. Let Your Heart
Keep Beating…!!!