Valvular abnormalities

Question 1

What is S1?

Answer 1

S1 (First Heart Sound)
Cause: Closure of mitral and tricuspid valves at the start of ventricular systole.
Heard best: At the apex of the heart.
Clinical relevance: A loud S1 may indicate mitral stenosis; a soft S1 may suggest mitral regurgitation or reduced ventricular function.

Question 2

What is S2?

Answer 2

S2 (Second Heart Sound)

Cause: Closure of aortic and pulmonary valves at the end of systole (beginning of diastole).

Split S2: Can be physiological (normal with inspiration) or pathological (e.g. pulmonary hypertension or bundle branch block).

Clinical relevance: A loud P2 component suggests pulmonary hypertension; a soft or absent A2 may indicate severe aortic stenosis.

Question 3

What is S3?

Answer 3

S3 (Third Heart Sound)
Cause: Rapid passive ventricular filling during early diastole.

Heard best: With the bell of the stethoscope at the apex in the left lateral decubitus position.

Normal in: Children and young adults.

Abnormal in: Older adults; suggests ventricular failure or volume overload (e.g., in heart failure, mitral regurgitation).

Question 4

What is S4?

Answer 4

S4 (Fourth Heart Sound)
Cause: Atrial contraction against a stiff, non-compliant ventricle during late diastole.

Heard best: Just before S1, at the apex.

Always pathological: Associated with left ventricular hypertrophy, aortic stenosis, hypertrophic cardiomyopathy, or ischemic heart disease.

Question 5

What are murmurs?

Answer 5

Murmurs are due to turbulent blood flow caused by valvular stenosis (narrowing) or regurgitation (incompetence/leakage).

Question 6

What is Aortic stenosis?

Answer 6

Cause: Calcification (age-related), bicuspid aortic valve (congenital), rheumatic disease.

Murmur: Ejection systolic murmur (crescendo-decrescendo).

Heard best: Right upper sternal border, radiates to carotids.

Symptoms: Syncope, angina, dyspnoea (classic triad).

Question 7

What is Aortic regurgitation?

Answer 7

Cause: Infective endocarditis, aortic root dilation, rheumatic fever, Marfan syndrome.

Murmur: Early diastolic, decrescendo.

Heard best: Left sternal edge, patient leaning forward in expiration.

Features: Bounding pulse, wide pulse pressure, collapsing pulse.

Question 8

Mitral stenosis

Answer 8

Mitral Stenosis
Cause: Rheumatic heart disease (most common), congenital.
Murmur: Mid-diastolic rumbling murmur with opening snap.
Heard best: Apex, in left lateral position.
Signs: Malar flush, atrial fibrillation, left atrial enlargement.

Question 9

Mitral Regurgitation

Answer 9

Mitral Regurgitation
Cause: Mitral valve prolapse, rheumatic disease, papillary muscle rupture (MI), endocarditis.
Murmur: Pansystolic (holosystolic) murmur.
Heard best: At the apex, radiates to axilla.
Symptoms: Dyspnoea, fatigue, pulmonary congestion.

Question 10

Tricuspid Stenosis

Answer 10

Tricuspid Stenosis
Cause: Rheumatic fever, carcinoid syndrome.
Murmur: Diastolic rumble, increased with inspiration (Carvallo’s sign).
Heard best: Lower left sternal border.
Features: Right atrial enlargement, jugular venous distension.

Question 11

Tricuspid Regurgitation

Answer 11

Tricuspid Regurgitation
Cause: RV dilatation (e.g. pulmonary hypertension), endocarditis (especially IV drug use).
Murmur: Pansystolic, louder on inspiration.
Heard best: Lower left sternal edge.
Features: Pulsatile liver, elevated JVP, hepatomegaly.

Question 12

Pulmonary stenosis

Answer 12

Pulmonary Stenosis
Cause: Congenital heart disease, Noonan syndrome.
Murmur: Ejection systolic murmur.
Heard best: Left upper sternal border.
Signs: RV hypertrophy, cyanosis (if severe).

Question 13

Pulmonary Regurgitation

Answer 13

Pulmonary Regurgitation
Cause: Pulmonary hypertension (most common), carcinoid, endocarditis.
Murmur: Early diastolic, decrescendo murmur.
Heard best: Left sternal edge, increases with inspiration.
Associated sign: Graham Steell murmur.