1. BASIC INTRODUCTION OF ANATOMY OF HEART
4 Chambers
2 Atria - upper
2 Ventricles- lower
Valves
Tricaspid valve
Bicaspid valve
Semilunar valve

2. Conducting system
Pacemaker
S.A node
Internodal fibers
A.V node
Bundle of his
Bundle branch
Purkinje fibers

3. CARDIAC CYCLE
Cardiac cycle is the proper occurring of events as blood enters the atria, leaves the ventricles and then starts again.
Phases of cardiac cycle
Phase of the cardiac cycle when myocardium is relaxed is termed DIASTOLE.
Phase of the cardiac cycle when the myocardium contracts is termed SYSTOLE.

4. Alternating periods of systole and diastole occur in cardiac cycle.
Phases of the cardiac cycle.
Atrial systole.
Ventricular systole.
Diastole of the whole heart. REST
Atrial and ventricular systoles do not occur at the same time, but their
diastoles occur at the same time during the diastole of the whole
heart.

5. STAGES OF CARDIAC CYCLE
ATRIAL SYSTOLE…. Contraction of atrium
VENTRICULAR SYSTOLE…. Contraction of ventricles
Isometric (isovolumetric) contraction phase
Rapid ejection phase
Slow ejection phase
DIASTOLE OF THE WHOLE HEART…. Relaxation of whole
heart
Protodiastole
Isometric (isovolumetric) relaxation phase
Rapid filling phase
Slow filling phase

6. Ventricular Filling Period [ventricular diastole, atrial systole]
Isovolumetric Contraction Period [ventricular systole]
Ventricular Ejection Period [ventricular systole]
Isovolumetric Relaxation Period [ventricular diastole, atrial diastole]

8. 1. Rest
Both atria and ventricles in relaxation…………. Diastole.
Blood is filling both atria and ventricles due to low pressure conditions.
2. Atrial Systole
Atria contract.
Ventricular get filled with blood which comes from atria.
3. Isovolumetric Ventricular Contraction
A stage just before complete contraction of ventricles.
Increased pressure in the ventricles causes the AV valves to close.
CREATES THE FIRST HEART SOUND (LUB)
Atria go back to diastole.
No blood flow as still semilunar valves are closed.

9. 4. Ventricular Ejection
Intraventricular pressure overcomes aortic pressure
Semilunar valves open
Blood is ejected …WHICH IS PURE OXYGENATED BLOOD
5. Isovolumetric Ventricular Relaxation
Intraventricular pressure drops below aortic pressure
Semilunar valves close
SECOND HEART SOUND (DUP)
Pressure still hasn’t dropped enough to open AV valves so volume remains same (isovolumetric)
THIS IS THE PERIOD WHEN BOTH VENTRICLE AND ATRIA ARE IN
DIASTOLE, ATRIAL & VENTRICULAR DIASTOLE OCCUR SAMETIME

12. CARDIAC OUTPUT Pulmonary Artery Blood CARDIAC OUTPUT VENOUS RETURN
PERIPHERAL
BLOOD FLOW

13. CARDIAC OUTPUT CARDIAC OUTPUT = STROKE VOLUME X HEART RATE
Cardiac Output (CO) is the blood volume pumped by the left ventricle each minute into the aorta.
Normal value = 5-6 liters/ minute
Cardiac output is calculated as follows:
CARDIAC OUTPUT = STROKE VOLUME X HEART RATE

14. Stroke volume is the volume of blood pumped by each
ventricle per beat; normally it is about 70 ml/ beat.
Heart rate is the number of heart beats per minute;
normally it is about 72 beat/ minute.
SO CARDIAC OUTPUT = (70ml X 72beat) per minute.

15. STROKE VOLUME End systolic volume (ESV) End diastolic volume (EDV)
During diastole of the ventricles, filling of the ventricles
with blood normally increases the volume of each
ventricle to about ml.
The volume of blood present in each ventricle at the end
of ventricular diastole is called END-DIASTOLIC VOLUME
(EDV) and it is about ml.

16. During ventricular systole, as the ventricles empty, the volume decreases about ml out of ml which is pumped out called Stroke volume as it is about 70 ml/ beat.
So at the end of ventricular systole, the remaining volume of blood in each ventricle is about ml.
The volume of blood present in each ventricle at the end of ventricular systole is called END-SYSTOLIC VOLUME (ESV) and it is about ml.
( ) – (50-60) = 70-80
So the volume of blood ejection by each ventricle during each ventricular systole is called stroke volume= 70-80ml

17. STROKE VOLUME SV = (EDV— ESV) both volumes within the heart
1. EDV = After complete filling
ESV = After stroke volume remaining blood
inside chamber.
(70-80ml) = ( ml) – (50-60ml) So
EDV= ESV+ SV
( ml) = (50-60ml) + (70-80ml)

18. The output of both ventricles is equal, so the output of the
right ventricle goes into the pulmonary circulation equals
the output of the left ventricle into the systemic circulation.