52. Murmur Flashcards
Infective endocarditis.
a) Risk factors
b) Most commonly affected valves
c) Most common organisms
d) Clinical features
e) Criteria for diagnosis
a) Valvular heart disease, prosthetic valves, valvular surgery, bicuspid aortic valve, IVDU, previous IE
b) Mitral, then aortic, then mixed aortic-mitral, then tricuspid (mainly IVDUs), then pulmonary (rare)
c) Staph aureus (especially in prosthetic valves and in IVDUs), streptococci (viridans, ABCDG), pseudomonas, enterococci, HACEK, fungus
d) - Fever + new murmur; also, fatigue, flu-like illness, loss of appetite, weight loss, back pain, pleuritic pain, abdominal symptoms
- Cardiac decompensation: SOB, heart failure, fluid overload
- Immunological: petechiae, splinter haemorrhages, clubbing, Roth’s spots (retina), glomerulonephritis, Janeway lesions (palm/soles), Osler nodes (fingers)
- Embolic complications: CVA, lung or spleen
e) Dukes criteria: (require 2 major, 1 major + 3 minor, or 5 minor criteria)
- Major criteria (2 positive blood cultures, evidence of endocardial involvement - ECHO or murmur)
- Minor criteria (fever, immunological phenomena, predisposition to IE, etc.)
Aortic stenosis (AS).
a) Murmur
b) Other signs o/e
c) Presentation
d) Risk factors
e) Management
f) Peak velocity through valve: normal, mild AS, moderate AS, severe/critical AS
g) Severe AS: criteria
a) ESM, loudest at RSE 2nd ICS, radiates to carotids, soft S2 (absent in severe AS)
b) Narrow pulse pressure, pulsus parvus et tardus (slow rising pulse)
c) SAD: syncope (poor prognosis), angina, dyspnoea, signs of heart failure, new murmur, in LVH may have displaced apex beat and S4, if heart failure may have signs of overload and S3 (gallop rhythm)
d) Age, bicuspid Ao valve
e) - Diagnosis: ECG, CXR, ECHO (gold standard)
- Conservative: monitor, control CHD risk
- Good oral health/ avoid tattoos and piercings etc.
- Surgical: valve replacement (TAVI / open surgery)
f) - Normal: 1.0 m/s
- Mild: 2.5–2.9 m/s
- Moderate: 3.0–4.0 m/s
- Severe: > 4.0 m/s
g) Any one of:
- Symptomatic: SAD (syncope, angina, dyspnoea)
- Valve area < 1cm squared
- Peak velocity > 4.0 m/s
- Mean gradient > 40 mmHg
Aortic regurgitation (AR).
a) Murmur
b) Other signs o/e
c) Presentation
d) Risk factors
e) Management
a) Early diastolic murmur, accentuated by leaning forward in held expiration
(Diastolic murmurs - ARMS: aortic regurgitation, mitral stenosis - AR comes first so this is the early one)
b) Wide pulse pressure, water-hammer pulse
c) Often asymptomatic, maybe heart failure or collapse
d) Age, Bicuspid aortic valve, Ao valve replacement, Rheumatic fever, Infective endocarditis, Collagen vascular diseases.
e) - ECG, CXR and ECHO (gold standard)
- Conservative: monitor, control CHD risk
- Good oral health/ avoid tattoos and piercings etc.
- If symptomatic / severe - surgery (repair, replace)
Management of suspected IE
a) Initial workup
b) Empirical treatment
c) Targeted therapies
d) Indications for surgery
a) - A-E: oxygen, IV access, bloods (FBC, CRP)
- Blood cultures from 3 different peripheral sites
- Fluids as necessary
- ECG
- Transthoracic ECHO (if negative, but still suspect IE - do a TOE)
b) NVE, no sepsis: amoxicillin + gentamicin
NVE, sepsis: vancomycin + gentamicin
PVE: vanc + gent + rifampicin
c) 4-6 week courses.
- Staph aureus: IV fluclox (vanc if MRSA) and (if PVE) + gent + rifampicin
- Strep: IV benpen
d) - Failure of medical management
- Severe valvular disease/ decompensation
Note: routine antibiotic prophylaxis for at-risk patients undergoing procedures like dental work is no longer offered
Mitral regurgitation (MR).
a) Murmur
b) Other signs o/e
c) Presentation
d) Risk factors
e) Management
a) Pansystolic murmur, loudest at the apex and radiating to the axilla
b) Signs of heart failure
c) Acute MR (may be following MI) - acute pulmonary oedema; chronic MR (asymptomatic for years, progresses to heart failure causing increasing SOBOE)
d) Coronary artery disease, heart failure, IE, following mitral valve surgery, connective tissue disease, Marfan’s
e) CXR, ECG (P mitrale), ECHO (gold standard),
- Good oral health/ avoid tattoos and piercings etc.
- Medical: acute - as per acute heart failure (Loop diuretics, Oxygen, Opiates, Nitrates). Chronic - as per chronic heart failure (BB, ACE)
- Monitor
- Surgical: repair or replace
Mitral stenosis
a) Murmur
b) Other signs o/e
c) Presentation
d) Risk factors
e) Management
a) Mid-late diastolic rumbling murmur
b) Malar flush, loud S1 (opening snap)
c) SOB, AF, embolic complications
d) Rheumatic fever, age
e) - CXR, ECG (AF, P mitrale), ECHO
- Conservative: diuretics, anticoagulation, etc.
- Surgical: percutaneous mitral commissurotomy (PMC)
Marfans.
a) Mutation and inheritance
b) Clinical features (MSK, CV, other)
c) Management
a) Fibrillin 1 protein mutation on Ch 15, autosomal dominant
b) - MSK: tall, thin, pectus excavatum/ carinatum, arachnodactyly, kyphoscoliosis, hypermobility
- CV: aortic root dilatation and aneurysm, mitral valve prolapse and regurgitation, arrhythmias, predisposition to aortic dissection and aneurysm
- Other: lens dislocation, pneumothorax, dural ectasia
c) - Monitor: ECHO, pelvic XR, etc.
- Medical: BB and ARBs
- Surgical: e.g. aortic valve repair
Mechanical heart valves.
a) All patients with mechanical (metallic) aortic or mitral valves must receive what drug indefinitely?
b) Those at low risk of bleeding should also receive what drug?
a) Warfarin. Target INR:
- Aortic: 2.5 (2.0 - 3.0)
- Mitral/mixed: 3.0 (2.5 - 3.5)
b) Aspirin
