Thread: Cardiac cycle - concept, origin of heart sounds, murmurs and other sounds

Understanding cardiac cycle is the first step in the learning of cardiovascular medicine.

Let us discuss these in brief. Respond briefly on the concept of cardiac cycle, and the mechanism by which different heart sounds and murmurs are produced.

Focus on - First, second, third and fourth heart sounds, abnormal sounds in mitral stenosis, mitral regurgitation, mitral valve prolapse, aortic stenosis, aortic regurgitation and tricuspid regurgitation. Not just the murmur, but the mechanism of production.

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Cardiac Cycle


The Heart's ConductionSystem


4 Components


The sinoatrial (SA) node

Atrioventricular (AV) node

Purkinje fibres

The bundle of His

Length :0.8 seconds, occurs 72 times/min


The cardiac cycle has two basic components:

(1) a contraction phase (systole) during which blood is ejected from the heart

(2) a relaxation phase (diastole) during which the chambers of the heart are filled
with blood.

When atria contracts, the AV valves remain open and additional blood is forced into the ventricles from the veins.

The aortic and pulmonary (pulmonic) semilunar valves remain closed .

After the ventricles have filled (mostly by blood returning from the large veins) and the atria have contracted, the AV valves close as the ventricles begin their contraction.

Ventricular contraction forces blood through the semilunar valves into the aorta and pulmonary trunk.

Next, as the ventricles begin to relax, the aortic and pulmonic semilunar valves close, the AV valves open, and blood flows into the ventricles to begin another cycle.
While the atria are in systole, the ventricles are relaxed (in diastole). The atria relax during ventricular systole and remain in this phase even during a portion of ventricular diastole.

Blood (like any other fluid) tends to flow from a region of high pressure to one of lower pressure.

As each chamber of the heart fills with blood, the pressure increases within it. The blood moves out of the chamber, when the various one-way valves guarding those chambers permit it to do so.

Although the ventricles exist as closed chambers for a brief moment, the pressure within them soon exceeds that in the aorta and pulmonary trunk. When this happens the aortic and pulmonic semilunar valves are forced open under pressure and blood rushes out of the ventricles and is driven into these large vessels. Accompanying the opening of the semilunar valves is a rapid decline in intraventricular pressure that continues until the pressure within the ventricles becomes less than that of the atria. When this pressure differential is reached, blood within the atria pushes the AV valves open and begins to fill the ventricles once again.

Pathophysiology Of S1 Heart Sounds

The first heart sound - S1 - is in time with the pulse in your carotid artery in your neck. The sound of the tricuspid valve closing may be louder in patients with pulmonary hypertension due to increased pressure beyond the valve. Non-heart-related factors such as obesity, muscularity, emphysema, and fluid around the heart can reduce both S1 and S2.

The position of the valves when the ventricles contract can have a big effect on the first heart sound. If the valves are wide open when the ventricule contracts, a loud S1 is heard. This can occur with anemia, fever or hyperthyroid.

When the valves are partly closed when the ventricule contracts, S1 is faint. Beta-blockersproduce a fainter S1. Structural changes in the heart valves can also affect S1. Fibrosis and calcification of the mitral valve may reduce S1, while stenosis of the mitral valve may cause a louder S1.

Pathophysiology Of S2 Heart Sounds

The second heart sound marks the beginning of diastole - the heart's relaxation phase - when the ventricles fill with blood. In children and teenagers, S2 may be more pronounced. Right ventricular ejection time is slightly longer than left ventricular ejection time. As a result, the pulmonic valve closes a little later than the aortic valve.

Higher closing pressures occur in patients with chronic high blood pressure, pulmonary hypertension, or during exercise or excitement. This results in a louder A2 (the closing sound of the
On the other hand, low blood pressure reduces the sound. The second heart sound may be "split" in patients with right bundle branch block, which results in delayed pulmonic valve closing. Left bundle branch block may cause aortic valve closing (A2) to be slower than pulmonic valve closing (P2).

Pathophysiology Of S3 Heart Sounds

During diastole there are 2 sounds of ventricular filling: The first is from the atrial walls and the second is from the contraction of the atriums. The third heart sound is caused by vibration of the ventricular walls, resulting from the first rapid filling so it is heard just after S2. The third heart sound is low in frequency and intensity. An S3 is commonly heard in children and young adults. In older adults and the elderly with heart disease, an S3 often means heart failure.
Pathophysiology Of S4 Heart Sounds

The fourth heart sound occurs during the second phase of ventricular filling: when the atriums contract just before S1. As with S3, the fourth heart sound is thought to be caused by the vibration of valves, supporting structures, and the ventricular walls. An abnormal S4 is heard in people with conditions that increase resistance to ventricular filling, such as a weak left ventricle.

Pathophysiology Of Murmurs

A vague sound associated with turbulent blood flow through a heart valve. Turbulent blood flow may be the result of:
1. increased flow across a normal valve
2. forward flow across an irregular or constricted valve, or into an enlarged heart chamber
3. back-flow through an insufficient valve
Types of murmurs include:

• systolic murmur - occurs during a heart muscle contraction. Systolic murmurs are divided into ejection murmurs (due to blood flow through a narrowed vessel or irregular valve) and regurgitant murmurs.

• diastolic murmur - occurs during heart muscle relaxation between beats. Diastolic murmurs are due to a narrowing of the mitral or tricuspid valves, or regurgitation of the aortic or pulmonary valves.

• continuous murmur - occurs throughout the cardiac cycle.

First heart tone S1 "lub"

The first heart tone, or S1, is caused by the sudden block of reverse blood flow due to closure of the atrioventricular valves, mitral and tricuspid, at the beginning of ventricular contraction, or systole. When the pressure in the ventriclesrises above the pressure in the atria, venous blood flow entering the ventricles is pushed back toward the atria, catching the valve leaflets, closing the inlet valves and preventing of blood from the ventricles back into the atria. The S1 sound results from reverberation within the blood associated with the sudden block of flow reversal by the valves.
Second heart tone S2 "dub"

The second heart tone, or S2, is caused by the sudden block of reversing blood flow due to closure of the aortic valve and pulmonary valve at the end of ventricular systole, i.e beginning of ventricular diastole. As the left ventricle empties, its pressure falls below the pressure in the aorta, aortic blood flow quickly reverses back toward the left ventricle, catching the aortic valve leaflets and is stopped by aortic (outlet) valve closure. Similarly, as the pressure in the right ventricle falls below the pressure in the pulmonary artery, the pulmonary (outlet) valve closes. The S2 sound results from reverberation within the blood associated with the sudden block of flow reversal.




Third heart sound S3

The third heart sound is not of valvular origin, as it occurs at the beginning of diastole just after S2. This sound occurs when the left ventricle is not very compliant, and at the beginning of diastole the rush of blood into the left ventricle causes vibration of the valve leaflets and the chordae tendinae.
The third heart sound is normal in children and young adults, but disappears before middle age. Abnormal reemergence of this sound late in life indicates a pathological state, often a sign of a failing left ventricle as in dilated congestive heart failure (CHF). This sound is called a protodiastolic gallop, a type of gallop rhythm.


Fourth heart sound S4

The rare fourth heart sound S4 is sometimes audible in healthy children, but when audible in an adult is called a presystolic gallop. This gallop is a sign of a pathologic state, usually a failing left ventricle. This sound occurs just after atrial contraction ("atrial kick") and is the sound of blood being forced into a stiff/hypertrophic left ventricle. The combined presence of S3 and S4 is a quadruple gallop. At rapid heart rates, S3 and S4 may merge to produce a summation gallop.

Gradations of Murmurs

Grade
Description
Grade 1
Very faint, heard only after listener has "tuned in"; may not be heard in all positions.
Grade 2
Quiet, but heard immediately after placing the stethoscope on the chest.
Grade 3
Moderately loud.
Grade 4
Loud, with palpable thrill.
Grade 5
Very loud, with thrill. May be heard when stethoscope is partly off the chest.
Grade 6
Very loud, with thrill. May be heard with stethoscope entirely off the chest.

MITRAL STENOSIS

Mitral stenosis (MS) is a narrowing of the inlet valve into the left ventricle that prevents proper opening during diastolic filling. Patients with mitral stenosis typically have mitral valve leaflets that are thickened, commissures that are fused, and/or chordae tendineae that are thickened and shortened.

The most common cause of mitral stenosis is rheumatic fever (RF). Apparantly 40% of patients with rheumatic heart disease have isolated mitral stenosis.

Mitral regurgitation
The mitral valve is composed of the valve leaflets, the mitral valve annulus (which forms a ring around the valve leaflets), the papillary muscles (which tether the valve leaflets to the left ventricle, preventing them from prolapsing into the left atrium), and the chordae tendineae (which connect the valve leaflets to the papillary muscles). A dysfunction of any of these portions of the mitral valve apparatus can cause mitral regurgitation.
Mitral regurgitation can be divided into the following 3 stages: acute, chronic compensated, and chronic decompensated. In the acute stage, which usually occurs with a spontaneous chordae tendineae rupture secondary to myocardial infarction, there is a sudden volume overload on an unprepared left ventricle and left atrium. The volume overload on the left ventricle increases left ventricular stroke work. Increased left ventricular filling pressures, combined with the transfer of blood from the left ventricle to the left atrium during systole, results in elevated left atrial pressures. This increased pressure is transmitted to the lungs resulting in acute pulmonary edema and dyspnea.
Chronic compensated phase begins, when the patient tolerates acute phase. The chronic compensated phase results in eccentric left ventricular hypertrophy. The combination of increased preload and hypertrophy produces increased end-diastolic volumes, which, over time, result in left ventricular muscle dysfunction. This muscle dysfunction impairs the emptying of the ventricle during systole. Therefore, regurgitant volume and left atrial pressures increase, leading to pulmonary congestion.

Mitral valve prolapse
It occurs when the valve between your heart's left upper chamber (left atrium) and the left lower chamber (left ventricle) doesn't close properly. When the left ventricle contracts, the valve's leaflets bulge (prolapse) upward or back into the atrium. Mitral valve prolapse sometimes leads to blood leaking backward into the left atrium, a condition called mitral valve regurgitation.
One or both leaflets of the valve are too large, or the chordae tendinea (the strings attached to the underside of the leaflets, connected to the ventricular wall) are too long (redundant), resulting in uneven closure of the valve during each heartbeat. Because of uneven closure of the leaflets, the valve bulges back, or "prolapses," into the left atrium like a parachute. When this happens, a very small amount of blood may leak through, moving backward from the ventricle to the atrium.
The valve still works well, and the heart pumps normally. Prolapse does not cause damage to the heart over time. Only 2% of people have other structural heart problems along with mitral valve prolapse.

Aortic stenosis
The aorta is the large artery that originates in the left ventricle (lower chamber) of the heart. Aortic stenosis is the narrowing or obstruction of the heart's aortic valve, which prevents it from opening properly and blocks the flow of blood from the left ventricle to the aorta.

As the aortic valve becomes more narrow, the pressure increases inside the left heart ventricle. This causes the left heart ventricle to become thicker, which decreases blood flow and can lead to chest pain. As the pressure continues to increase, blood may back up into the lungs and you may feel short of breath. Severe forms of aortic stenosis prevent enough blood from reaching the brain and rest of the body. Lightheadedness and fainting can result.
Aortic stenosis may be present from birth (congenital), or it may develop later in life (acquired). It is caused by many disorders. One common cause is rheumatic fever, a complication of untreated strep throat. Calcification of the valve can also cause this condition. In this case, the condition is usually not seen until a person reaches their 70s
Aortic regurgitation

Aortic valve regurgitation or aortic regurgitation is a condition that occurs when your heart's aortic valve doesn't close tightly. Aortic valve regurgitation allows blood that was just pumped out of your heart to leak back into it.
The leakage of blood may prevent your heart from efficiently pumping blood out to the rest of your body. If your heart isn't working efficiently, you may feel fatigued and short of breath.
Aortic valve regurgitation can develop suddenly or over decades. It has a variety of causes, such as rheumatic fever. Once aortic valve regurgitation becomes severe, surgery is usually required to repair or replace the aortic valve.
Aortic valve regurgitation is also called aortic insufficiency or aortic incompetence.

Tricuspid regurgitation
Tricuspid regurgitation is a disorder involving backward flow of blood across the tricuspid valve which separates the right ventricle (lower heart chamber) from the right atrium (upper heart chamber).
This occurs during contraction of the right ventricle and is caused by damage to the tricuspid heart valve or enlargement of the right ventricle.
The most common cause of tricuspid regurgitation is not damage to the valve itself, but enlargement of the right ventricle, which may be a complication of any disorder that causes failure of the right ventricle.

Cardiac Cycle

The cardiac cycle is the sequence of events that occur when the heart beats. The cycle has two main phases: diastole, when the heart ventricles are relaxed, and systole, when the ventricles contract. One cardiac cycle is defined as the contraction of the two atria followed by contraction of the two ventricles.


Each heart beat, or cardiac cycle, is divided into two phases of contraction and relaxation, stimulated by electrical impulses from the sinoatrial node (SA node). The time during which ventricular contraction occurs is called systole. The time between ventricular contractions, during which ventricular filling occurs, is called diastole (also known as the relaxation phase).

In early diastole, the ventricles relax, the semilunar valves close, the atrioventricular valves open and the ventricles fill with blood. In mid diastole, the atria and ventricles are relaxed, the semilunar valves are closed, the atrioventricular valves are open, and the ventricles keep filling with blood. In late diastole, the SA node sends an electrical impulse to the atria, which causes the atria to contract and the ventricles to fill with more blood. The electrical signal that causes contraction moves from the atria toward the ventricles. Before it does, the impulse from SA node reaches the atrioventricular node (AV node). The AV node delays the signal so that the ventricle can contract all at once rather than a little bit at a time.

Prior to systole, the electrical signal passes from the AV node down the AV bundle, also known as the bundle of His, to the Purkinje fibers. The fibers allow the fast spread of the electrical signal to all parts of the ventricles, and the electrical signal causes the ventricles to contract. Systole begins with the closure of the atrioventricular valves. During systole, the ventricles contract, the semi- lunar valves open, and blood is pumped from the ventricles to the aorta.


Pathophysiology of 3rd & 4th heart sound

The third heart sound (S3), when audible, occurs early in ventricular filling, and may represent tensing of the chordae tendineae and the atrioventricular ring, which is the connective tissue supporting the AV valve leaflets. This sound is normal in children, but when heard in adults it is often associated with ventricular dilation as occurs in systolic ventricular failure.

The fourth heart sound (S4), when audible, is caused by vibration of the ventricular wall during atrial contraction. This sound is usually associated with a stiffened ventricle, and therefore is heard in patients with ventricular hypertrophy, myocardial ischemia, or in older adults.

Murmurs

Murmurs are abnormal heart sounds that are heard using a stethoscope. The sounds most commonly originate from the abnormal movement of blood across valves and between cardiac chambers.

Murmurs may be physiological (benign) or pathological (abnormal). Abnormal murmurs can be caused by stenosis restricting the opening of a heart valve, causing turbulence as blood flows through it. Stenosis of the aortic valve typically produces a systolic ejection murmur. This is more common in older adults or in those individuals having a two, not a three leaflet aortic valve. Valve insufficiency (or regurgitation) allows backflow of blood when the incompetent valve is supposed to be closed. Regurgitation through the tricuspid or pulmonary valves essentially never produces audible murmurs.

CARDIAC CYCLE


The cardiac cycle is the sequence of events that occur when the heart beats. There are two phases of this cycle. There are 2 phases of the cycle :

• Diastole – ventricles relax, represents filling of ventricles
• Systole – ventricles contract, represents ejection of blood from ventricles

The cardiac cycle diagram depicts changes in :

• aortic pressure (AP)
• left ventricular pressure (LVP)
• left atrial pressure (LAP)
• left ventricular volume (LV Vol)
• heart sounds during a single cycle of cardiac contraction and relaxation.

These changes are related in time to the electrocardiogram.

During the diastole phase :

Atria and ventricles relax

¯

opening of atrioventricular valves

¯

de-oxygenated blood from the superior and inferior flows in the right atrium
¯
the open atrioventricular valves allow blood to pass through to the ventricles
¯
SA node contracts triggering the atria to contract
¯
right atrium empties its contents into the right ventricle
¯
tricuspid valve prevents the blood from flowing back into the right atrium.

During the systole phase :

The right ventricle receives impulses from the Purkinje fibres and contracts
¯
the atrioventricular valves close and the semilunar valves open
¯
de-oxygenated blood is pumped into the pulmonary artery
¯
the pulmonary valve prevents the blood from flowing back into the right ventricle
¯
the pulmonary artery carries the blood to the lungs
¯
the blood picks up oxygen and is returned to the left atrium of the heart by the pulmonary veins

HEART SOUNDS

First heart sound (S1) “lub”

1. Caused by sudden block of reverse blood flow due to closure of atrioventricular valve, mitral and tricuspid, at the beginning of ventricular contraction (systole).

2. When the pressure in the ventricles rises above the pressure in the atria, venous blood flow entering the ventricles is pushed back toward the atria, catching the valve leaflets, closing the inlet valves and preventing regurgitation of blood from the ventricles back into the atria.

3. Results from reverberation within the blood associated with the sudden block of flow reversal by the valves.

Second heart sound (S2) “dub”

1. Caused by the sudden block of reversing blood flow due to closure of the aortic valve and pulmonary valve at the end of ventricular systole, i.e beginning of ventricular diastole.

2. As the left ventricle empties, its pressure falls below the pressure in the aorta, aortic blood flow quickly reverses back toward the left ventricle, catching the aortic valve leaflets and is stopped by aortic (outlet) valve closure.

3. Similarly, as the pressure in the right ventricle falls below the pressure in the pulmonary artery, the pulmonary (outlet) valve closes.

4. Results from reverberation within the blood associated with the sudden block of flow reversal.

Third heart sound (S3)

1. It is a protodiastolic sound - is not of valvular origin, as it occurs at the beginning of diastole just after S2.

2. This sound occurs when the left ventricle is not very compliant, and at the beginning of diastole the rush of blood into the left ventricle causes vibration of the valve leaflets and the chorda tendinae.

3. Normal in children and young adults, but disappears before middle age.

4. Pathologically seen in congestive cardiac failure (CCF) – a sign of failing left ventricle.

5. Is also called a prodiastolic gallop, a type of gallop rhythm.

Fourth heart sound (S4)

1. Called a presystolic gallop when it is audible in adults.

2. Sometimes audible in healthy children.

3. This gallop is pathological – usually a sign of failing left ventricle.

4. Occurs just after atrial contraction ("atrial kick") and is the sound of blood being forced into a stiff/hypertrophic left ventricle.

5. The combined presence of S3 and S4 is a quadruple gallop.

6. At rapid heart rates, S3 and S4 may merge to produce a summation gallop.

Anand Kamalanathan
041303007
Batch 15 Group B1
MMMC

CARDIAC CYCLE







i. Cardiac cycle is the term referring to all or any of the events related to the flow of blood that occur from the beginning of one heartbeat to the
beginning of the next.
ii. The frequency of the cardiac cycle is the heart rate.
iii. Every single 'beat' of the heart involves three major stages:

v atrial systole
v ventricular systole
v complete cardiac diastole.

iv. The term diastole is synonymous with relaxation of a muscle.
v. Throughout the cardiac cycle, the blood pressure increases and decreases.



Atrial systole




Atrial systole is the contraction of the heart muscle (myocardia) of the left and right atria. Normally, both atria contract at the same time. The term systole is synonymous with contraction (movement or stretching) of a muscle. Electrical systole is the electrical activity that stimulates the myocardium of the chambers of the heart to make them contract. This is soon followed by Mechanical systole, which is the mechanical contraction of the heart.
As the atria contract, the blood pressure in each atrium increases, forcing additional blood into the ventricles. The additional flow of blood is called atrial kick.
Atrial kick is absent if there is loss of normal electrical conduction in the heart, such as during atrial fibrillation, atrial flutter, and complete heart block. Atrial kick is also different in character depending on the condition that the heart is in like stiff heart, that is found in patients with diastolic dysfunction.


Detection of atrial systole

Electrical systole of the atria begins with the onset of the P wave on the EKG.






Ventricular systole




Ventricular systole is the contraction of the muscles (myocardia) of the left and right ventricles.
Detection of ventricular systole

Heart sounds

The closing of the mitral and tricuspid valves (known together as the atrioventricular valves) at the beginning of ventricular systole cause the first part of the "lub-dub" sound made by the heart as it beats. Formally, this sound is known as the First Heart Tone, or S1. This first heart tone is created by the closure of mitral and tricuspid valve and is actually a two component sound, M1, T1.

The second part of the "lub-dub" (the Second Heart Tone, or S2), is caused by the closure of the aortic and pulmonic valves at the end of ventricular systole. As the left ventricle empties, its pressure falls below the pressure in the aorta, and the aortic valve closes. Similarly, as the pressure in the right ventricle falls below the pressure in the pulmonary artery, the pulmonic valve closes. The second heart sound is also two components, A2, P2. The aortic valve closes earlier than the pulmonic valve and they are audibly separated from each other in the second heart sound.

Electrocardiogram

In an electrocardiogram, electrical systole of the ventricles begins at the beginning of the QRS complex.





Complete cardiac diastole







Cardiac Diastole is the period of time when the heart relaxes after contraction in preparation for refilling with circulating blood. Ventricular diastole is when the ventricles are relaxing, while atrial diastole is when the atria are relaxing. Together they are known as complete cardiac diastole.
During ventricular diastole, the pressure in the (left and right) ventricles drops from the peak that it reaches in systole. When the pressure in the left ventricle drops to below the pressure in the left atrium, the mitral valve opens, and the left ventricle fills with blood that was accumulating in the left atrium. Likewise, when the pressure in the right ventricle drops below that in the right atrium, the tricuspid valve opens, and the right ventricle fills with blood that was accumulating in the right atrium.










Heart Sounds
The heart sounds are the noises generated by the beating heart and the resultant flow of blood through it. This is also called a heartbeat. In cardiac auscultation, an examiner uses a stethoscope to listen for these sounds, which provide important information about the condition of the heart.
In healthy adults, there are two normal heart sounds often described as a lub and a dub (or dup), that occur in sequence with each heart beat.
First heart tone S1, the "lub"

The first heart tone, or S1, is caused by the sudden block of reverse blood flow due to closure of the atrioventricular valves, mitral and tricuspid, at the beginning of ventricular contraction, or systole. When the pressure in the ventricles rises above the pressure in the atria, venous blood flow entering the ventricles is pushed back toward the atria, catching the valve leaflets, closing the inlet valves and preventing regurgitation of blood from the ventricles back into the atria. The S1 sound results from reverberation within the blood associated with the sudden block of flow reversal by the valves.
Second heart tone S2 the "dub"

The second heart tone, or S2, is caused by the sudden block of reversing blood flow due to closure of the aortic valve and pulmonary valve at the end of ventricular systole, i.e beginning of ventricular diastole. As the left ventricle empties, its pressure falls below the pressure in the aorta, aortic blood flow quickly reverses back toward the left ventricle, catching the aortic valve leaflets and is stopped by aortic (outlet) valve closure. Similarly, as the pressure in the right ventricle falls below the pressure in the pulmonary artery, the pulmonary (outlet) valve closes. The S2 sound results from reverberation within the blood associated with the sudden block of flow reversal.



Third heart sound S3


Rarely, there may be a third heart sound S3. The third heart sound or protodiastolic sound is not of valvular origin, as it occurs at the beginning of diastole just after S2. This sound occurs when the left ventricle is not very compliant, and at the beginning of diastole the rush of blood into the left ventricle causes vibration of the valve leaflets and the chordae tendinae.
The third heart sound is normal in children and young adults, but disappears before middle age. Abnormal reemergence of this sound late in life indicates a pathological state, often a sign of a failing left ventricle as in dilated congestive heart failure (CHF). This sound is called a protodiastolic gallop, a type of gallop rhythm.




Fourth heart sound S4


The rare fourth heart sound S4 is sometimes audible in healthy children, but when audible in an adult is called a presystolic gallop. This gallop is a sign of a pathologic state, usually a failing left ventricle. This sound occurs just after atrial contraction ("atrial kick") and is the sound of blood being forced into a stiff/hypertrophic left ventricle. The combined presence of S3 and S4 is a quadruple gallop. At rapid heart rates, S3 and S4 may merge to produce a summation gallop.




Heart murmurs
Heart murmurs are generated by turbulent flow of blood, which may occur inside or outside the heart. Murmurs may be physiological (benign) or pathological (abnormal). Abnormal murmurs can be caused by stenosis restricting the opening of a heart valve, causing turbulence as blood flows through it. Valve insufficiency (or regurgitation) allows backflow of blood when the incompetent valve is supposed to be closed. Different murmurs are audible in different parts of the cardiac cycle, depending on the cause of the murmur.
Abnormal Sounds
Mitral Stenosis
Tapping apical impulse
Diastolic thrill at the apex
Loud First Heart Sound
Presence of an opening snap
mid-diastolic murmur at the apex

Mitral Regurgitation
Systolic thrill ath the apex
Soft first heart sound
Presence of left sided 3rd heart sound
Pansystolic murmur at the apex

Aortic Stenosis
Heaving apical impulse
Systolic thrill over the aortic area and over the caroptids
Ejection Click
2nd heart sound
Ejection Systolic Murmur at the aortic area

Aortic Regurgitation
Early Diastolic Murmur of longer duration
Decrescendo and high pitched on expiration heard with diaphragm of stethoscope
Diastolic thrill at the aortic area (severe)
2nd heart sound musical or loud

Tricuspid Regurgitation
Pansysolic murmur high pitched and better heard on inspiration
“carvallo’s sign”
murmur heard at tricuspid area
Right sided S3 may be present

CARDIAC CYCLE

DEfinition

Types
1. systolic
2. diastolic

Diastolic murmurs

1. Early diastolic murmur:

-starts just after S2 and gradually decreases in intensity (persists up to opening of mitral and tricuspid valve)
-seen in aortic regurgitation, pulmonary regurgitation

2. Mid-diastolic murmur :

-begins well after S2 and may persist up to next S1 (during passive ventricular filling)
-seen in mitral stenosis, tricuspid stenosis

Systolic murmurs

1. Late systolic murmur :

-begins well after S1 (clear gap between murmur and S!) and continues up to S2
-seen in mitral valve prolapse, papillary muscle dysfunction

2. Pan (holosystolic) murmur :

-begins with S1 and ends with S2 or its component (A2 or P2)
-S1 is usually muffled
-intensity of murmur is uniformed through the systole
-seen in MR,TR, VSD

Types
1. systolic
2. diastolic

Diastolic murmurs


1. Early diastolic murmur:

-starts just after S2 and gradually decreases in intensity (persists up to opening of mitral and tricuspid valve)

-seen in aortic regurgitation, pulmonary regurgitation

2. Mid-diastolic murmur :

-begins well after S2 and may persist up to next S1 (during passive ventricular filling)

-seen in mitral stenosis, tricuspid stenosis

Systolic murmurs


1. Late systolic murmur :

-begins well after S1 (clear gap between murmur and S!) and continues up to S2

-seen in mitral valve prolapse, papillary muscle dysfunction

2. Pan (holosystolic) murmur :

-begins with S1 and ends with S2 or its component (A2 or P2)

-S1 is usually muffled

-intensity of murmur is uniformed through the systole

-seen in MR,TR, VSD