Download Core Clinical Problem 52: Murmur Summary ΔΔ (Index Conditions

Core Clinical Problem 52: Murmur
Summary ΔΔ (Index Conditions numbered)
Vascular /
haematological
Infective
Traumatic
Autoimmune
Metabolic
Inflammatory
Neoplastic
Benign
Congenital/
hereditary
Degenerative
Aortic dissection (6)
Atrial ball-valve thrombi
Rheumatic fever (1b)
Endocarditis (1c)
Aortic dissection (6)
Cardiomyopathies (5)
Cardiomyopathies (5)
Atrial tumours
Innocent murmurs (3)
Congenital heart disease (2)
Septal defects
Tetralogy of Fallot
Patent ductus arteriosis
Coarctation of the aorta
Marfan’s syndrome (4)
Hypertrophic cardiomyopathy (5)
Valvular heart disease (1a)
Stenotic
Regurgitative
Basic Sciences
Structure of the heart
1
Development of the heart
Cell layer of origin = Mesoderm
Left-right positioning determined by factor called nodal, wafted left by cilia
1. Formation of primitive heart tube from right and left endocardial heart tubes.
2. Cardiac looping- the heart tube bends and grows into the pericardial cavity. Dilations
form: bulbous cordis → ventricle → atrium → Right and left horns of sinus venosum
http://www.youtube.com/watch?v=g5UTzj9LOhQ
3. Cardiac septation Ventral and dorsal endocardial cushions → Septum intermedium
 Septum primum and septum secondum grown down from root of atria
leaving foramen ovale
 Muscular ventricular septum grows up from floor of ventricle
 Bulbar ridges in bulbus cordis → Spiral aortico-pulmonary septum → Fuses
with septum intermedium and then with ventricular septum
A good video of the whole process:
http://www.youtube.com/watch?v=5DIUk9IXUaI
DIASTOLE
Isovolumic reslaxation
End systolic volume (approx. 50%)
LV pressure < LA pressure (venous
Brief rise in aortic pressure
return)
Aortic valve closes
Mitral valve opens
LV pressure < Aortic pressure
Rapid filling (+ active relaxation
Ejection
i.e. sucking in)
The
Aortic valve opens
LV pressure = LA pressure
cardiac
LV pressure > Aortic pressure
Filling temporarily stops
cycle
Isovolumic contraction
(diastasis)
LV pressure < Aortic pressure
LA contracts
Mitral valve closes
LV pressure < LA pressure
LV pressure > LA pressure
Further filling (15-20%
Ventricles begin to contract
contribution, at rest)
SYSTOLE
End diastolic volume
2
1. Valvular Heart Disease
a. Degenerative Valve Disease
Pathophysiology
Leads to heart failure, which is often responsible for signs and symptoms...
 Mitral Stenosis →
o Left atrial hypertrophy + dilatation
o Pulmonary hypertension
o Right ventricular hypertrophy, dilatation + failure.
 Mitral Regurgitation →
o Pulmonary hypertension if acute
o Left ventricular enlargement to maintain S.V.
 Aortic Regurgitation → Left ventricular enlargement + failure
Symptoms



...Of induced heart failure:
Left sided- dyspnoea, orthopnoea
Right sided- abdominal pain and distension, lethargy
Aortic stenosis: Exercise induced syncope, angina, dyspnoea
PMH- Rheumatic fever
Signs


...Of induced heart failure
Murmur
Aortic Stenosis
Aortic Regurgitation
Mitral Stenosis
Mitral Regurgitation
Tricuspid Regurgitation
Location of
lesion
Semi-lunar
Valves
AV
Valves
Timing
Systolic
Stenosis
(Ejection)
Regurgitation
(Pan)
Diastolic
Regurgitation
(Early)
Stenosis
(Mid)
Radiates to carotids
Slow rising carotid pulse
Heard at tricuspid area, patient lent forward, held expiration
Bounding/Collapsing pulse
Heard best with patient rolled 450 to left
Malar flush
Low volume pulse
Radiates to left axilla
Pulsatile, enlarged liver
Investigations
CXR: enlargement of chamber behind problem
ECG: changes reflecting hypertrophy of effected chamber
Echocardiography: shows volume and flow changes
Management
 Surgery: Balloon valvotomy/ replacement
 For HF eg. Diuretics
3
Prophylactic antiobiotics against infective endocarditis are not recommended, unless the
patient is undergoing a GI or GU procedure at a site of suspected infection.
b. Rheumatic Fever
Pathophysiology
Abnormal immune response to infection with Group A β-haemolytic strep
Now rare in developed countries (sanitation, antibiotics, reduced virulence)
Features
Preceding pharyngitis 2-6 weeks before
Diagnostic criteria:
2 major / 1 major + 2 minor
+ evidence of previous strep (culture or ASOT)
Major:
1. Polyarthritis- ankles, knees + wrists, tender, moderate redness + swelling, flitting
between joints for 1-2 months.
2. Pancarditis Endocarditis- significant murmur, valve dysfunction
 Myocarditis- heart failure
 Pericarditis- pericardial friction rub, effusion, tamponade
3. Erythema marginatum- pink macular rash spreading outwards
4. Sydenham’s chorea- after 2-6 months, involuntary movements + emotionally labile
for 3-6 months
5. Subcutaneous nodules- rare, extensor surfaces, hard, painless, pea-sized
Minor:
o Fever
o Polyarthralgia
o Raised ESR, CRP, leucocytosis
o Prolonged P-R interval on ECG
o Previous history of rheumatic fever
Management
Acute- high dose aspirin (corticosteroids if ineffective), pericardiocentesis if required, treat
heart failure with ACE inhibitors + diuretics
Prophylaxis (recurrence prevention)- monthly benzathine penicillin IM
Complications
Scarring + fibrosis of heart valves → Mitral stenosis (commonest)
4
c. Infective endocarditis
Risk factors
Congenital heart disease (except secundum ASD)
Prosthetic valves
Causes of bacteraemia:
 IVDU
 Dentistry
 UTI, catheters
 Surgery/ TOP/ fracture
Most caused by α-haemolytic streptococcus e.g. viridans
Presentation
 Fever + New murmur = IE until proven otherwise
 Rigors
 Night sweats
 Weight loss
 Pallor
 Splinter haemorrhages
 Necrotic skin lesions
o Osler’s: tender, finger pulp
o Janeway: non-tender, palms
 Retinal infarcts (Roth spots)
 Clubbing (late)
 Splenomegaly
 Arthritis/arthralgia
 Neurological signs from cerebral infarction
Investigations
 FBC: normochromic normocytic anaemia, ↑ neutrophils
 Urine: microscopic haematuria
 ESR ↑
 Blood cultures (do multiple before starting antibiotics)
 Echocardiography: may detect vegetation (mass of bacteria, neutrophils and fibrin)
Management
Antibiotics e.g. High dose penicillin + an aminoglycoside (gentamicin) IV for 6 weeks
Surgical removal of any prosthetic material may be necessary
Complications
Glomerulonephritis → acute renal failure
Emboli → Abscess in brain/kidney/spleen/GI/ lung (if right-sided valve)
5
2. Congenital Heart Disease
Cyanotic and non-cyanotic congenital heart disease
Acyanotic congenital heart disease
 Left to right shunts
o Ventricular septal defect
o Persistent ductus arteriosus
o Atrial septal defect
 Outflow obstruction
o Pulmonary stenosis
o Aortic stenosis
o Coarctation of the aorta
Cyanotic congenital heart disease
 Tetralogy of Fallot
 Transposition of the great arteries
 Complete atrioventricular septal defect
Atrial septal defect
Pathophysiology
 Secondum ASD involving centre of atrial septum and foramen ovale
 Primum ASD: partial atrioventricular defect. The communication is between the
bottom end of the atrial septum and the AV valve, with a three-leaflet regurgitant
left AV valve
Presentation
 Commonly asymptomatic
 Recurrent chest infections/ Wheeze
 Symptoms of heart failure
 On auscultation
o Ejection systolic murmur heard best at upper left sternal edge (due to
increased outflow from left-to-right shunt)
o Fixed widely split second heart sound
o In AVSD- pansystolic apical murmur (AV valve regurgitation)
Investigations
CXR: Cardiomegaly, enlarged pulmonary arteries, increased pulmonary vascular markings.
ECG: Secondum: Partial right bundle branch block, right axis deviation
Partial AVSD: Left ‘superior QRS’ axis deviation
Echocardiogram (cross-sectional): Mainstay of diagnosis
Management
 Correction of secondum ASD: cardiac catheterisation + occlusive device
 Correction of partial AVSD: surgical
 Should take place at 3-5 years
Complications
 Right heart failure

Arrhythmias in adulthood
6
Ventricular septal defect
Pathophysiology
Perimembranous- located adjacent to the tricuspid valve
Muscular- surrounded by muscular septum
Small = smaller than aortic valve (up to 3 mm), Large if same size of bigger
Presentation
Small VSD
 Asymptomatic
 Thrill (lower sternal edge)
 Loud pansystolic murmur (lower left sternal edge)
 Quiet pulmonary second sound
Large VSD
 Heart failure, with breathlessness and failure to thrive after 1 week, tachypnoea,
tachycardia and hepatomegaly.
 Recurrent chest infections
 Soft pansystolic murmur/ no murmur
 Apical mid-diastolic murmur (increased flow through mitral)
 Loud pulmonary second sound (raised pulmonary artery diastolic pressure)
Investigations
 Chest x-ray: normal in small; large shows cardiomegaly, enlarged pulmonary arteries,
increased pulmonary vascular markings, and pulmonary oedema
 ECG: normal in small; large shows biventricular hypertrophy and pulmonary
hypertension (T wave upright, if inversted suggests no PH)
 Echocardiogram: assess anatomy and haemodynamic effects with doppler
Management
Small lesions mostly close spontaneously.
Promote good dental hygiene; prophylactic ABx no longer recommended
Large lesions also require:
 Additional calorie input
 Diuretics and captopril for HF
 Surgery at 3-6 months
Complications
 Pulmonary vascular disease (capillaries damaged by high pressures)
 Eisenmenger’s (unusual before second decade of life)
 Bacterial endocarditis
Patent ductus arteriosus
Pathophysiology
Failure to close by 1 month post-term (not pathological in preterm infants)
Flow occurs from aorta to pulmonary artery due to reversal of pressure gradient (i.e. left-toright shunt).
Increased risk in preterm or unwell babies (sepsis, pulmonary hypertension…)
7
Presentation
 Continuous murmur beneath left clavicle
 Collapsing/ bounding pulse (high pulse pressure)
 Rarely symptomatic
Investigations
 Chest x-ray: usually normal, if large shows same features as large VSD
 ECG: usually normal, if large shows same features as large VSD
 Echocardiogram- cross-sectional with doppler
Management
Prostaglandin inhibitor: indomethacin
Closure at 1 yr by cardiac catheterisation and insertion of coil/ occlusive device
Complications
 Rarely, right heart failure, pulmonary hypertension
 Bacterial endocarditis
Aortic stenosis
Pathophysiology
Aortic valve leaflets partially fused together restricting outflow
Often associated with mitral stenosis and coarctation of the aorta
Presentation
 Asymptomatic murmur
 Small volume, slow rising pulse
 Carotid thrill
 Ejection systolic murmur- maximal upper right sternal edge, radiates to neck
 Delayed soft aortic second sound
 Apical ejection click
 Severe neonatal presentation:
o Heart failure
o Duct-dependent systemic circulation → Shock
 If severe:
o Reduced exercise tolerance (dyspnoea)
o Chest pain on exercise
o Exercise syncope
Investigations
CXR: Normal/ Prominent left ventricle with post-stenotic dilatation of ascending aorta
ECG: May show left ventricular hypertrophy (deep S in V2, tall R in V6), of left ventricular
strain if severe (inverted T wave in V6)
Echocardiography
Management
Indications for intervention: symptoms on exercise or high resting pressure gradient on
echo (> 64 mmHg across aortic valve) → Balloon valvotomy
8
Most with early severe disease will eventually require valve replacement
Pulmonary stenosis
Pathophysiology
Pulmonary valve leaflets partially fused restricting outflow from right heart
Presentation
 Asymptomatic
 Ejection systolic murmur best at upper left sternal edge +/- thrill
 Ejection click at upper left sternal edge
 Soft or absent second pulmonary sound
 If severe
o Neonate with duct-dependent circulation
o Prolonged right ventricular impulse
o Delayed pulmonary valve closure on auscultation
Investigations
Chest x-ray: Normal/ Post-stenotic dilation of pulmonary artery
ECG: Evidence of right ventricular hypertrophy (Upright T wave in V1)
Echocardiography
Management
Indications for intervention: symptoms on exercise or high resting pressure gradient on
echo (> 64 mmHg across pulmonary valve) → Balloon valvotomy
Complications
Right heart failure
Coarctation of the aorta
Pathophysiology
Constriction of aorta in area where ductus arteriosus joins
Condition worsens gradually over years
Presentation
 Asymptomatic
 Systemic hypertension in right arm (always)
 Ejection systolic murmur between shoulder blades
 Collaterals
 Radio-femoral delay
Investigations
CXR: Rib notching (large collateral intercostal arteries), visible notch in descending aorta
ECG: Left ventricular hypertrophy (deep S in V2 + tall R in V6), left ventricular strain if severe
coarctation/hypertension (T wave inversion in V6)
MR angiography
Echocardiography
9
Management
When severe, correction by cardiac catheterisation and stenting
Left heart outflow obstruction in a sick infant
→ Duct-dependent lesions
Features
Interruption of the aortic arch
Murmur, heart failure,
At site of DA, + VSD
circulatory collapse,
Associated with DiGeorge syndrome
weak femorals, BP in
arms > in legs
Hypoplastic left heart syndrome
Circulatory collapse, all
Underdevelopment of entire left heart
peripheral pulses
Mitral + aortic atresia, coarctation, ASD
weak/absent
Management
ABC
Immediate
prostaglandin infusion
ABC
Immediate
prostaglandin infusion
Surgery (complex)
Tetralogy of Fallot
Pathophysiology
1. Large VSD
2. Overriding aorta
3. Right ventricular outflow obstruction (subpulmonary stenosis)
4. Right ventricular hypertrophy
Presentation
 Antenatal diagnosis
 Murmur in first 2 months of life
 Cyanosis if severe
 Collapse (can be duct dependent)
 Hypercyanotic spells- rapid onset cyanosis, with irritability/ inconsolable crying,
breathlessness, pallor
 Clubbing (older children)
 Loud, harsh ejection systolic murmur at left sternal edge
 Single second heart sound
Investigations
Chest x-ray: Normal/ In older children- small heart with uplifted apex, pulmonary artery
‘bay’ (dip), decreased pulmonary vascular markings
ECG: Normal at birth, right ventricular hypertrophy when older (Upright T in V1 with ‘pure R’
i.e. no S wave)
Echocardiography, though cardiac catheterisation may also be necessary
Management
Cyanosed neonate → shunt inserted between subclavian artery and pulmonary artery
(Blalock-Taussig shunt), or balloon dilatation of pulmonary outflow tract
Surgery (6 months): Closure of VSD and relieve right outflow obstruction
10
Hypercyanotic spells lasting > 15 mins →
 Sedation and morphine
 IV propranolol
 IV fluids
 Bicarbinate (correct acidosis)
 Muscle paralysis and ventilation (reduce oxygen demand)
Complications
Hypercyanotic spells → MI, stroke, death
Transposition of the great arteries
Pathophysiology
Aorta connected to right ventricle and pulmonary artery to left ventricle (deoxygenated
blood returned to body and oxygenated returned to lungs),
Co-existing VSD, ASD, or PDA associated and vital to be compatible with life.
Presentation
 Duct dependent so present at day 1-2 when closure occurs
 Cyanosiso Profound and life-threatening
o Milder with other abnormalities causing blood mixing.
 Clubbing if present after 1 year (rare)
 Single second heart sound, and signs of associated abnormalities
Investigations
Chest x-ray: Narrow upper mediastinum, ‘egg on side’ shape (RV hypertrophy and anteriorposterior aligned vessels), increased pulmonary vascular markings
ECG: Normal
Echocardiography
Management
Cyanotic neonate → Prostaglandin infusion (maintain DA), balloon atrial septostomy
Surgery: Open surgical correction in the first few days of life
Complete atrioventricular septal defect
Pathophysiology
 Mostly children with Down’s syndrome
 Defect in the middle of the heart
 Single regurgitant five-leaflet valve stretching across entire heart
 Pulmonary hypertension
Presentation
 Detection at antenatal screening
 Cyanosis at birth or heart failure in first 2-3 weeks
 Echocardiography screening of baby with Down’s syndrome
11
Investigations
ECG: Superior axis
Echocardiography
Management
Medical management of heart failure and surgical correction at 3-6 months
Tricuspid atresia
Pathophysiology
Only left ventricle functional, right small. Blood circulated through foramen ovale from RA
to LA then from LV through a VSD to right outflow tract.
Presentation: Cyanosis- new-born or duct dependent
Management
 Shunt between subclavian artery and pulmonary artery (Blalock-Taussig)
 Pulmonary artery banding to reduce pulmonary blood flow if breathless
 Surgical: correction not possible, instead superior and inferior vena cava connected
to pulmonary artery.
3. Innocent murmurs
Commonly heard in childhood or during pregnancy
 Ejection systolic
o Caused by turbulent flow
o Soft, heard at left sternal edge (right heart)
o Or short and ‘buzzing’ over apex (aorta)
o No thrill, no radiation
o Asymptomatic
o Often heard in anaemia or fever (increased cardiac output)
 Venous hum
o Turbulent flow in head and neck veins
o Continuous rumble under either clavicle
o Distinguished from PDA because it disappears on lying down
o Mammary souffle = venous hum from engorged breast vessels in pregnancy
12
4. Marfan’s Syndrome
Pathophysiology
 Autosomal dominant mutation in fibrillin-1 gene
 Connective tissue disorder: decreased extracellular microfibril formation.
Features
Major (>2 to diagnose):
 Lens dislocation, usually upwards
 Aortic dissection/ dilatation (→ aortic regurgitation)
 Dural ectasia (large neural canal)
 Arachnodactyly (long fingers)
 Arm span > height
 Pectus deformity (carinatum or excavatum)
 Scoliosis
 Pes planus (flat feet)
Minor:
 Mitral valve prolapse
 High-arched palate
 Joint hypermobility
 Kyphoscoliosis
 Hernias (diaphragmatic/inguinal)
Investigations
 MRI (aid diagnosis by showing dural ectasia)
 Echocardiogram (annual)
Management
 β-blocker helps prevent cardiovascular complications
 Prophylactic surgery to prevent aortic dissection when diameter >5cm
 Consider inducing precocious puberty in very tall girls
5. Cardiomyopathies
Cardiomyopathy = Primary myopathy of cardiac muscle
Types
 Dilated
 Hypertrophic
 Restrictive
Presentation: usually with heart failure, as systolic or diastolic dysfunction, or both. Other
presentations include chest pain, syncope and sudden death
Investigation: Echocardiography, ECG, Chest x-ray
13
Causes
Dilated
Diffuse coronary artery
disease
Infection
Viral e.g. coxsackie
Chagas disease
HIV
Toxoplasma
Toxins
Alcohol
Chemo e.g.
doxorubicin
Granulomatous e.g. sarcoid
Metabolic e.g. thyrotoxicosis
Familial tendency with
variable inheritance
Pathophysiology
Features
Systolic dysfunction
ECG
Non-specific ST and T
changes
Q waves
+/- bundle branch block
For heart failure…
Diuretics, ACE inhibitors,
Angiotension receptor
blockers, Beta blockers,
Digoxin
Pacing: ICD or biventricular
Anticoagulationprophylactic for mural
thrombi should be
considered
Transplant
20% mortality first year, 10%
per year after
Treatment
Prognosis
LV and RV failure
Cardiomegaly
Functional AV valve
regurgitation
S3
S4
Hypertrophic
Genetic (most cases):
numerous mutations
identified, most autosomal
dominant but many cases
are spontaneous
Diastolic dysfunction
+/- outflow obstruction
Starting at 20-40 years:
Exertional dyspnoea,
angina, syncope
Sudden death
Ejection murmur
+/- mitral regurge
S4
Bifid carotid pulse
No cardiomegaly
LV hypertrophy and
ischaemia
Deep septal Q waves
Beta blockers
+/- verapamil (rate limiting
and –ve inotrope)
+/- disopyramide
+/- septal myotomy
+/- alcohol ablation
AV pacing
Transplant
Restrictive
Non-obliterative
Myocardial infiltration
by abnormal substance
Genetic
Haemochromatosis
Lysosomal storage
diseases (Fabry’s,
Gauchers)
Connective tissue
Amyloidosis
Diffuse systemic
sclerosis
Other
Hypereosinophilia
Sarcoid
Radiation
Obliterative
Fibrosis of endocardium
+ subendocardium
Diastolic dysfunction
Exertional dyspnoea and
fatigue
LV +/- RV failure
Functional AV valve
regurgitation
Mild or no cardiomegaly
LV hypertrophy OR
Low voltage
Endocardial resection
Phlebotomy for
haemochromatosis
Hydroxyurea for
hypereosinophilia
Not transplant- would
generally recur
1% annual risk of sudden
death
70% 5 year mortality
14
6. Aortic Dissection
Pathophys.
Wall damaged → Blood enters between intima and media in false channel, obstructing flow
through normal lumen
Life-threatening complications: (most likely in acute dissections)
 Compromise of blood supply to tributary arteries including coronary arteries
 Aortic valve dilatation and regurgitation
 Heart failure
 Fatal aortic rupture into pericardium of left pleural space
Underlying causes:
 Hypertension
 Atherosclerosis
 Acquired connective tissue disorder: Behçet's syndrome, Giant cell arteritis,
Takayasu’s arteritis
 Congenital connective tissue disorder:
o Marfan’s syndrome
o Ehler’s Danlos syndrome
o Turner’s syndrome
o Coarctation of the aorta
o Bicuspid aortic valve
o Familial thoracic aortic aneurysm
 Trauma: deceleration injury
 Iatrogenic: valve surgery, aortic catheterisation
Types:
 Type I: Starts in ascending aorta and extends to or beyond arch. 50%
 Type II: Start in and confined to ascending aorta. 35%
 Type III: Start in descending aorta and usually extend distally. 15%
Symptoms and Signs
Sudden tearing pain in central chest or intrascapular
May radiate to back
Syncope
Branch occlusions→
 Hemiplegia (carotid)
 Unequal arm pulses/BP/Acute arm ischaemia
 Paraplegia (anterior spinal)
 Anuria (renal)
Investigation: Chest x-ray, transoesophageal echo/ CT angiogram/ MR angiogram
Management Urgent surgery, blood pressure control
15