The document discusses the cardiac cycle, heart sounds, pulse, and electrocardiogram (ECG). The cardiac cycle occurs over 0.8 seconds and involves ventricular systole, ventricular diastole, arterial systole, and arterial diastole. There are four heart sounds that occur due to valve vibrations - S1, S2, S3, and S4. Pulse is the expansion of arteries during systole and diastole and is normally felt at sites like the radial artery. The ECG records electrical changes in the heart during each cardiac cycle.

1. Cardiac cycle and Heart sounds
Cardiac cycle:
The cardiac cycle events that occur from the beginning of one heart beat to the beginning of the next
are called cardiac cycle.
Cardiac cycle time:
The cardiac cycle time is 0.8 seconds.(minute/beat)
When heart rate is 75 beat/minute.This is the time required for one complete cardiac cycle.
The events of cardiac cycle:
Arterial events-
Arterial systole- 0.1 seconds
Arterial Diastole- 0.7 seconds
Ventricular events-
Ventricular systole- 0.3 seconds
Ventricular Diastole- 0.5 seconds
Ventricular Systole:
 Iso-metric concentration period
 Maximum ejection period
 Reduced ejection period
Ventricular Diastole:
 Protodiatolic period
 Iso-metric/Iso-volumic relaxation period
 First rapid filling phase
 slow filling phase
 Last rapid filling phase

2. Q. What are the changes occur during the cardiac cycle?
The changes occurs during cardiac cycle:
1- changes in pressure-
Intra-ventricular pressure changes.
Intra-arterial pressure changes.
Pressure changes within aorta.
Pressure changes within pulmonary artery.
2- Changes in volume -
Arterial volume changes.
Ventricular volume changes.
3- Production of heart sound.
4- Production of pulse.
5- Electrocardiogram changes. (ECG)
Heart sound:
Sound which is produce during cardiac cycle due to vibration of valve and is transmitted to the chest
wall after travelling various structure of the chest wall called heart sound.
Types:
Heart sound are 4 in types-
1. First heart sound
2. second heart sound
3. Third heart sound
4. Fourth heart sound
First Heart sound:
It is caused by the sudden closure of the AV valve.
Nature- Dull and prolonged like the word LUB.
Duration- (0.09-0.16) seconds. [Average- 0.14 seconds]

3. Second heart sound:
It is caused by the sudden closure of the semi-lunar valve.
Nature- Short and sharp like the sound DUP.
Duration- (0.1-0.14) seconds [average- 0.11 seconds ]
Third heart sound:
The third heart sound occurring during the opening of AV valve and where the rushing of blood through
the narrow opening.
Fourth heart sound:
The fourth heart sound is due to rapid inrush of blood from arteria to ventricle due to forceful
concentration of arteria.
*Third and fourth heart sound is audible for Rhonocardiogram.
Causes of heart sound:
1. Vibration of the leaves of the valves during closure.
2. Turbulence of blood during rapid rush of blood from arteria to the ventricle.
3. Vibration of the walls of the heart and major vessels around tje heart.
Site of auscultation of heart sound:
1. Mitral area-
In the left fifth intercostal space, Just medial to the mid clavicular line.
2. Tri-cuspid area-
Over the left border of the sternum in the left fourth intercostal space.
3. Aortic area-
At the right border of the sternum in the right second intercostal space.
4. Pulmonary area-
At the left border of the sternum in the left second intercostal space.
Q. Why vibration of valve is produced?
 During the closure of valve vibration of valve is produced.
 During the closure of AV valve first heart sound is produced.
 During the closure of semi-lunar valve the second heart sound is produced.

4. PULSE AND ECG
Pulse:
Pulse is the expansion and elongation of the arterial wall passively produced by pressure changes during
systole and diastole of ventricles.
Normal pulse rate- (60-100)/minute
Types of pulses:
Pulse are 2 in types-
1. Normal or catacrotic pulse
2. Abnormal pulse
Normal/catacrotic pulse are 2 types-
1. Arterial pulse
2. Venous pulse
Arterial pulses:
 Radial pulse
 Branchial pulse
 Axillary pulse
 Carotid pulse
 Femoral pulse
 Popliteal pulse
 Posterior tibial pulse
 Anterior dorsalis pedis pulse
Venous pulses:
 Jugular venous pulse
Abnormal pulses:
 Anacrotic pulse
 Dicroric pulse
 water hammer pulse or collapsing pulse
 Pulsus paradoxus
 Pulsus alternas
 Pulsus deficit
 Pulsus bisferiens

5.  Pulse can be counted by any part of the superficial artery.such as in the radial artery,known
as Radial artery. Also Carotid artery,Brachial artery(Albow Joint).
 Usually we count pulse in radial artery,Because it is exposure of the body.
Observation during taking pulse/Examination of pulse should include following aspect:
1. Rate of the pulse
2. Rhythmicity of pulse
3. Volume of pulse
4. Condition of vessel wall/Rapid and thread pulse
 Rate: Normal rate and Abnormal (Tachycardia,Bradycardia)
 Rhythm: Normally Rhythm-Regular pulse
Abnormally Rhythm- Irregular pulse(Arterial fibrillation)
 Volume: Hypovolumic and Hypervolumic
In healthy person volume of pulse is normal.
During exercise volume of the pulse increase.
 Rapid and thready: Haemorrhage (severe bleeding)
Characteristics of pulse:
I. Normal
II. Radio-Femoral delay
Q.Draw and level a normal pulse.
P-Percussion wave
T-Tidal wave
D-Dicrotic wave
N-Dicrotic Notch

6. Percussion wave:
percussion wave correspond to the ejection phase of Ventricular systole.
Tidal wave:
Tidal wave is due to the falling of blood column during slow ejection phase.
Dicrotic Wave:
Dicrotic wave is due to the closure of the aortic valve. At the end of the Ventricular systole.
Dicrotic Notch:
Dicrotic notch is due to the rebound of blood column from the closed aortic valve.
ECG(Electrocardiogram):
Electrocardiogram is the recording from the surface of the body of the electrical changes of the heart in
each cardiac cycle.