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Murmurs and Other Cardiovascular Signs

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Heart Murmurs

Overview

The normal heart sounds are S1 (first heart sound) and S2 (second heart sound). S1 is due to the closure of the mitral and tricuspid valves and S2 is due to the closure of the aortic and pulmonary valves. Heart murmurs are additional sounds as a result of turbulent blood flow. Ideally, blood flow should be laminar and silent. A thrill is a murmur significant enough to be palpable.

When listening to heart murmurs, it is important to establish if they’re systolic or diastolic. Systolic murmurs are mostly pathological but can be benign in children or pregnant women. Diastolic murmurs are always pathological.

Ejection systolic murmur

Late systolic murmur

  • Coarctation of the aorta – loudest below the left scapula
  • Mitral valve prolapse

Pansystolic murmur

Early diastolic murmur

Mid-late diastolic murmur

Other murmurs

  • Continuous machinery murmur in the left upper sternal border: patent ductus arteriosus

Causes

  • Aortic stenosis:
    • Degenerative calcification and fibrosis
    • Bicuspid aortic valve
    • Rheumatic fever
    • Hypertrophic obstructive cardiomyopathy
  • Aortic regurgitation:
  • Mitral stenosis:
    • Rheumatic fever
    • Degenerative calcification and fibrosis
    • Congenital
    • Connective tissue disease e.g. rheumatoid arthritis, systemic lupus erythematosus 
    • Infective endocarditis
  • Mitral regurgitation:
    • Coronary artery disease e.g. papillary muscle rupture
    • Infective endocarditis
    • Connective tissue disease e.g. systemic lupus erythematosus, Ehlers-Danlos syndrome, Marfan’s syndrome
    • Rheumatic fever
    • Congenital
  • Pulmonary stenosis:
    • Tetralogy of Fallot
    • Infective endocarditis
    • Connective tissue disease
  • Pulmonary regurgitation:
    • Can be a complication after correction of pulmonary stenosis or Tetralogy of Fallot
    • Connective tissue disease
    • Pulmonary hypertension
  • Tricuspid stenosis:
    • Rheumatic fever
    • Infective endocarditis
  • Tricuspid regurgitation:
    • Pulmonary hypertension
    • Rheumatic heart disease
    • Infective endocarditis, especially intravenous drug users
    • Congenital e.g. Ebstein’s anomaly

Heart Sounds

Overview

Normal heart sounds occur due to valves closing. The sound they make is often referred to as “lub-dub”:

  • S1, the first heart sound, “lub”:
    • Occurs due to the closure of the atrioventricular (AV) valves (mitral and tricuspid valves) at the start of systole
    • Valves close if the pressure in front of them is higher than the pressure behind them. This prevents the backflow of blood
  • S2, the second heart sound, “dub”:
    • Occurs due to the closure of the semilunar valves (aortic and pulmonary valves) once systole completes

Splitting of the S2 is seen during inspiration. This is because, during inhalation, the pressure inside the thorax decreases, allowing the lungs to fill with air and expand. This also increases venous return into the right atrium and right ventricle and decreases the return of blood from the lungs into the left atrium (the blood ‘wants to stay’ in the lungs because of the negative pressure surrounding the lungs). This results in it taking more time to pump out the blood from the right ventricle into the pulmonary artery, leading to a delay in the closure of the pulmonary valve compared to the aortic valve. This causes S2 to be split.

S2 splitting is pathological if it is ‘fixed’, meaning that it occurs irrespective of inspiration or not and may suggest an atrial septal defect.

S3 and S4

The addition of extra heart sounds S3 and S4 is also known as a gallop rhythm as it sounds similar to a gallop.

  • S3, a third heart sound, may be heard after S2
    • This may suggest increased blood volume in the ventricle and rapid filling and occurs due to tense chordae tendinae
    • This can be normal in young people as the ventricles may allow rapid filling, leading to tense chordae tendinae
    • In older people, it can suggest heart failure as their chordae tendinae are stiff and weak, reaching their limit and becoming tense sooner
  • S4, a fourth heart sound, may be heard after S3
    • This is always abnormal and occurs due to blood being forced into a stiff or hypertrophic ventricle.
    • This can occur in hypertrophic obstructive cardiomyopathy or severe aortic stenosis

Bruits

A bruit is a vascular murmur that occurs due to the turbulent flow of blood. This can occur due to increases in blood velocity or obstructive blood flow.

Pericardial friction rub

A pericardial friction rub occurs due to inflammation of the pericardial surfaces resulting in a rough sound similar to walking in fresh snow. The pericardium is a sac surrounding the heart with an inner and outer layer that is normally lubricated by a small amount of pericardial fluid to reduce friction. Inflammation leads to reduced lubrication, resulting in friction heard as a pericardial friction rub.

Pulse Signs

Pulsus paradoxus

Pulsus paradoxus describes an abnormally large decrease in systolic blood pressure (>10 mmHg) and a decrease in pulse strength during inspiration. It is seen in cardiac tamponade and severe asthma.

Pulsus bisferiens

Pulsus bisferiens describes a pulse with two peaks per cardiac cycle (a ‘double pulse’). This suggests aortic disorders (e.g. stenosis or regurgitation) or hypertrophic obstructive cardiomyopathy.

Pulsus alternans

Pulsus alternans describes alternating strong and weak pulses. This is seen in severe left ventricular failure.

Aortic Insufficiency Signs

Collapsing pulse

Also known as Corrigan’s pulse, a collapsing pulse is a sign of aortic regurgitation characterised by a pulse that is bounding and forceful that rapidly increases then collapses. This is felt by raising the patient’s arm vertically upwards and holding the patient’s forearm. Gravity causes an increased flow of blood to the arm and a resultant collapsing pulse.

De Musset’s sign

De Musset’s sign describes rhythmic bobbing of the head in sync with the heart and is a sign of aortic regurgitation. The nodding occurs due to an increase in pulse pressure as a result of aortic insufficiency.

Quincke’s sign

Quincke’s sign describes pulsations of the capillaries in the nailbeds that occur with each heart beat. This is a sign of aortic regurgitation.

Infective Endocarditis Signs

Roth’s spots

These are red spots with white centres seen on the retina due to haemorrhage of retinal capillaries. This is a sign of infective endocarditis.

Janeway lesions

Janeway lesions are erythematous, non-tender, macular lesions on the palms and soles of the hands associated with infective endocarditis. They occur due to immune complex deposition.

Osler’s nodes

Osler’s nodes are painful, erythematous, and raised lesions on the hands and feet associated with infective endocarditis. They occur due to immune complex deposition.

Pericardial Signs

Beck’s triad

Beck’s triad is the presence of:

  • Hypotension
  • Muffled/quiet heart sounds
  • Elevated jugular venous pressure

This is a sign of cardiac tamponade.

Vascular Signs

Allen’s test

Allen’s test assesses arterial blood flow to the hands. It involves the examiner occluding the radial and ulnar arteries for about 30 seconds while the hand is clenched as a fist. The patient opens their hand, which should appear blanched. Pressure from the ulnar artery is then removed and colour should return in around 10 seconds. If this does not occur, this suggests that the ulnar supply to the hand may not be sufficient if venepuncture or procedures involving the radial artery are performed.

Kussmaul’s sign

Kussmaul’s sign describes a paradoxical increase in jugular venous pressure (JVP) during inspiration. The JVP normally falls with inspiration due to decreased pressure in the thoracic cavity. This is seen in constrictive pericarditis and rarely seen in cardiac tamponade.

Other Signs

Jugular venous pressure

The jugular venous pressure (JVP) is assessed by looking at the jugular vein and can be used to assess cardiorespiratory disorders. It can be difficult to differentiate the JVP from the carotid artery. Some distinguishing features include:

  • The JVP is biphasic (‘beats twice’) whereas the carotid artery beats once
  • The JVP is non-palpable. If a pulse is felt, it is the carotid artery
  • The JVP is occludable. Lightly pressing on it occludes the jugular vein which then fills from above the occlusion.

An elevated JVP suggests venous congestion (such as heart failure). Kussmaul’s sign (discussed above) may also be seen with the JVP.

The JVP waveform also has different parts to it, each of which is associated with different pathologies (the a, x, c, v, and y waves). 

Parasternal heaves

Heaves are palpable heart impulses felt when the hand is rested just lateral to the left sternal edge. This is a sign of right ventricular hypertrophy.

Thrills

Thrills are palpable heart murmurs that are felt over the areas on the chest corresponding to the valves of the heart. They feel like a cat purring under the hand.

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