valvular heart disease

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quick recognition

Lesion	Classic clue	Auscultation
aortic stenosis	exertional syncope, angina, dyspnoea in elderly	crescendo-decrescendo systolic murmur → right upper sternal border, radiating to carotids
aortic regurgitation	wide pulse pressure, bounding pulses, early diastolic murmur	blowing early diastolic murmur → left sternal border
mitral stenosis	rheumatic fever history, AF, haemoptysis	low-pitched diastolic rumble → apex, opening snap
mitral regurgitation	holosystolic murmur → axilla, acute MR in MI setting	blowing holosystolic murmur → apex

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aortic stenosis

severity criteria

Parameter	Mild	Moderate	Severe	Very severe
peak jet velocity (m/s)	2.0–2.9	3.0–3.9	≥4.0	>5.0
mean gradient (mmHg)	<20	20–39	≥40	—
AVA (cm²)	>1.5	1.0–1.5	<1.0	—

Class I indications for replacement

• severe symptomatic AS (dyspnoea, syncope, angina)
• severe asymptomatic AS with LVEF <50%
• severe asymptomatic AS undergoing other cardiac surgery
• symptomatic low-flow low-gradient AS (reduced or preserved EF) — see below

low-flow low-gradient AS

Two distinct entities:

	classical LFLG	paradoxical LFLG
EF	reduced (<50%)	preserved (≥50%)
mechanism	LV can’t generate gradient	small hypertrophied LV, low stroke volume
diagnostic test	dobutamine stress echo — true severe AS shows AVA stays <1.0 cm² with ↑gradient	CT aortic valve calcium score (dobutamine not helpful — EF already normal)
calcium score threshold	—	≥2000 AU (men), ≥1200 AU (women) suggests true severe AS

medical management cautions

• vasopressor choice: phenylephrine (maintains coronary perfusion, reflexive bradycardia helps diastolic filling) or norepinephrine (mild inotropy without excessive tachycardia)
• avoid tachycardia — shortens diastolic filling time across the fixed obstruction

monitoring (asymptomatic)

Severity	Echo interval
mild	every 3–5 years
moderate	every 1–2 years
severe	every 6–12 months

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aortic regurgitation

Class I indications for surgery

• severe symptomatic AR
• severe asymptomatic AR with LVEF ≤55%
• severe AR undergoing other cardiac surgery

Class IIa

• severe asymptomatic AR with LV end-systolic dimension >50 mm (or >25 mm/m²)

management

• target SBP <140 mmHg
• standard HFrEF management if LV dysfunction develops
• afterload reduction does not substitute for surgery when thresholds are met
• TAVR is not an option for isolated chronic AR (insufficient calcification for valve anchoring)

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mitral stenosis

• almost exclusively rheumatic in origin
• severe MS: MVA ≤1.5 cm²

anticoagulation

VKA anticoagulation required if:

• rheumatic MS + AF
• prior embolic event (regardless of rhythm)
• LA thrombus

intervention

PMBC (percutaneous mitral balloon commissurotomy) — Class I:

• severe symptomatic MS + favourable valve anatomy

Contraindications to PMBC:

• LA thrombus
• greater than moderate MR
• unfavourable anatomy (heavy calcification, subvalvular fusion)

medical management

• rate control is critical — longer diastole = more filling time across the stenotic valve
• diuretics for congestion
• avoid tachycardia (exercise, AF with rapid ventricular response)

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mitral regurgitation

primary (degenerative) MR

Pathology of the valve apparatus (leaflets, chordae, papillary muscles). Most common: myxomatous degeneration / mitral valve prolapse. Severe = EROA ≥0.4 cm².

Class I indications for surgery:

• severe symptomatic primary MR
• severe asymptomatic primary MR with LVEF ≤60% or LVESD ≥40 mm

Repair is preferred over replacement when feasible — should be performed at experienced centres with <1% operative mortality.

secondary (functional) MR

Structurally normal leaflets; MR results from LV or LA dilatation causing annular distortion and leaflet malcoaptation. Severe = EROA ≥0.2 cm² (lower threshold than primary MR).

Management sequence:

1. maximise GDMT (including SGLT2 Inhibitors, Mineralocorticoid Receptor Antagonists)
2. CRT if indicated
3. percutaneous MV repair (MitraClip) if symptomatic despite maximal GDMT + LVEF 20–50%

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prosthetic valve anticoagulation

Valve type	Anticoagulation	Target INR
mechanical — any position	lifelong Warfarin	—
mechanical AVR (current gen, no risk factors)	Warfarin	2.5 (range 2.0–3.0)
mechanical MVR or AVR + risk factors	Warfarin	3.0 (range 2.5–3.5)
ON-X aortic	Warfarin + low-dose ASA	1.5–2.0
bioprosthetic	lifelong ASA 75–100 mg	—
bioprosthetic (post-surgical)	consider VKA INR 2.5 for first 3–6 months	2.5

• add ASA to mechanical valve anticoagulation only if separate antiplatelet indication (e.g. recent ACS, stent)

TAVR vs SAVR selection

Age	Preferred approach
<50 years	SAVR (mechanical preferred unless VKA contraindicated)
50–65 years	SAVR (mechanical or bioprosthetic — shared decision)
65–80 years	SAVR or TAVR both acceptable
>80 years or high surgical risk	TAVR preferred

Decision requires valve team assessment — STS score, frailty, anatomy, vascular access.

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what NOT to do

• vasodilate symptomatic severe AS — can be fatal
• use DOACs in rheumatic MS — INVICTUS showed inferiority to warfarin
• use DOACs with mechanical valves — increased events
• delay referral for asymptomatic severe AS with LVEF <50% — Class I indication regardless of symptoms
• attribute exertional symptoms in severe valve disease to deconditioning — exercise stress test if uncertain; symptoms provoked on stress testing = symptomatic patient (Class I for AVR)
• forget rate control in MS — tachycardia is poorly tolerated
• assume secondary MR needs surgery first — maximise GDMT and CRT before considering intervention

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key trials summary

Trial	Year	N	Intervention	Key result
PARTNER 3 (2019)	2019	1000	TAVR vs SAVR in low-risk severe AS	TAVR non-inferior to SAVR at 1 year; lower rate of composite endpoint
COAPT (2018)	2018	614	MitraClip vs GDMT in secondary MR	MitraClip reduced HF hospitalisations and mortality at 2 years
MITRA-FR (2018)	2018	304	MitraClip vs GDMT in secondary MR	No benefit — likely proportionate MR, less optimised GDMT
INVICTUS (2022)	2022	4565	rivaroxaban vs warfarin in rheumatic AF	rivaroxaban inferior — higher death, stroke, embolism