Pregnancy & Heart Disease

📋 Key Information Summary

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Cardiac disease is the leading cause of indirect maternal mortality in Australia and the UK, accounting for approximately 15–20% of maternal deaths.
Pregnancy imposes a 30–50% increase in cardiac output, 40–50% increase in plasma volume, and a physiological decline in systemic vascular resistance — these changes peak at 28–34 weeks gestation.
Modified WHO (mWHO) risk classification (I–IV) is the standard tool for preconception counselling; mWHO IV carries a contraindication to pregnancy.
Pulmonary arterial hypertension (PAH) carries a maternal mortality of 17–33% and is formally contraindicated (mWHO IV) — pregnancy should be avoided or terminated early.
Eisenmenger syndrome mortality approaches 30–50% per pregnancy; multidisciplinary management in a tertiary centre with ICU access is mandatory.
Severe symptomatic hypertrophic obstructive cardiomyopathy (HOCM) may deteriorate as venous return falls; beta-blockers are first-line therapy.
Anticoagulation in pregnancy requires switching from warfarin to low-molecular-weight heparin (LMWH) — enoxaparin 1 mg/kg BD with anti-Xa monitoring — particularly between 6–12 weeks and from 36 weeks.
Peripartum cardiomyopathy (PPCM) presents in the last month of pregnancy or within 5 months postpartum; early initiation of bromocriptine (2.5 mg BD for 2 weeks then 2.5 mg daily) plus standard HF therapy improves LV recovery.
ACE inhibitors, ARBs, direct renin inhibitors, and spironolactone are teratogenic and contraindicated in pregnancy; hydralazine + nitrate or labetalol are safe antihypertensive alternatives.
All pregnant women with known or suspected cardiac disease must be managed via a multidisciplinary cardio-obstetric team including obstetrician, cardiologist, anaesthetist, and neonatologist.
Vaginal delivery with assisted second stage (forceps/vacuum) is preferred for most cardiac conditions; Caesarean section is reserved for obstetric indications or haemodynamic instability.
Epidural analgesia reduces catecholamine surge and preload fluctuations — beneficial in most cardiac lesions except severe aortic stenosis or HOCM where a phenylephrine bolus strategy is preferred.
Aboriginal and Torres Strait Islander women have higher rates of rheumatic heart disease and delayed cardiac diagnosis in pregnancy — proactive screening and culturally safe care pathways are essential.

Introduction & Australian Epidemiology

Cardiac disease is a leading cause of indirect maternal mortality in Australia, responsible for approximately 15–20% of maternal deaths reported in successive triennial MBRRACE-UK and Australian Maternal Deaths Committee reports. Outcomes are worst with pulmonary hypertension, severe mitral stenosis, and cardiomyopathy — conditions in which the haemodynamic demands of pregnancy, labour, and the immediate postpartum period can precipitate acute decompensation, arrhythmia, or death.

The incidence of cardiac disease in pregnancy is rising, driven by increasing maternal age, the obesity epidemic, improved survival of congenital heart disease (CHD) patients into reproductive years, and immigration from regions with high rheumatic heart disease (RHD) prevalence. In Australia, the estimated prevalence of significant cardiac disease in pregnancy is 1–3%, with congenital heart disease now exceeding acquired valvular disease in most metropolitan centres. However, in Northern Australia and among Aboriginal and Torres Strait Islander communities, RHD — particularly severe mitral valve disease — remains a dominant cause of cardiac morbidity in pregnancy.

The CARPREG (Cardiac Disease in Pregnancy) and ZAHARA risk scores, along with the modified WHO (mWHO) classification, provide evidence-based frameworks for risk stratification. The mWHO classification is now the most widely adopted system in Australian tertiary centres. Accurate preconception risk assessment and multidisciplinary planning are the cornerstones of safe management.

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Mandatory multidisciplinary care: All women with cardiac disease of NYHA class II or above, mWHO class ≥ II, or any cyanotic heart disease must be referred to a tertiary cardio-obstetric team. Management in a facility without cardiac surgery and obstetric ICU capability is associated with significantly worse outcomes.

Physiological Cardiovascular Changes in Pregnancy

Understanding normal pregnancy physiology is essential for recognising pathological deterioration. The cardiovascular system undergoes profound adaptations beginning in the first trimester and peaking at 28–34 weeks of gestation.

Parameter	Change	Magnitude	Peak Timing
Cardiac output	↑ 30–50%	Up to 7 L/min	28–34 weeks
Heart rate	↑ 15–25 bpm	Resting HR 80–95 bpm	Third trimester
Stroke volume	↑ 20–30%	-	Mid-pregnancy
Plasma volume	↑ 40–50%	~4.5–5.5 L	32–34 weeks
Red cell mass	↑ 20–30%	-	Term
Systemic vascular resistance	↓ 20–30%	Nadir 70–80% baseline	Second trimester
Blood pressure	↓ then ↑	Nadir mid-2nd trimester	Returns to baseline by term
Oxygen consumption	↑ 20–30%	~300 mL/min	Term

Intrapartum Haemodynamic Shifts

Labour imposes additional cardiovascular stress. Each uterine contraction produces an auto-transfusion of approximately 300–500 mL into the central circulation, increasing cardiac output by 15–25% above the already elevated third-trimester baseline. The immediate postpartum period is the most hazardous — cardiac output peaks at 60–80% above pre-pregnancy values within 10–15 minutes of delivery due to relief of inferior vena caval compression and uterine auto-transfusion. This is the critical window for pulmonary oedema and acute heart failure.

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Post-delivery haemodynamic surge: The first 15 minutes after delivery represent the period of highest cardiac output in the entire pregnancy. Continuous monitoring, IV access, and readiness for emergency intervention are essential in all women with mWHO class ≥ II conditions.

High-Risk Conditions: Pulmonary Hypertension, HOCM & Eisenmenger Syndrome

Pulmonary Arterial Hypertension (PAH)

Pulmonary arterial hypertension in pregnancy remains one of the most dangerous cardiovascular conditions, classified as mWHO IV — pregnancy is formally contraindicated. Maternal mortality rates range from 17–33% in contemporary series, with the highest risk in idiopathic PAH and connective tissue disease-associated PAH.

The pathophysiology centres on the fixed pulmonary vascular bed failing to accommodate the 30–50% increase in cardiac output. The normal pregnancy-induced decline in systemic vascular resistance, combined with the fixed high pulmonary vascular resistance, creates a haemodynamic mismatch that precipitates right ventricular failure and cardiovascular collapse.

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Pregnancy contraindicated: Women with PAH should receive reliable contraception. If pregnancy occurs, early termination should be discussed. If the pregnancy continues, delivery must occur in a tertiary centre with pulmonary hypertension expertise, cardiac surgery capability, and ICU-level haemodynamic monitoring including pulmonary artery catheterisation.

Management of PAH in pregnancy involves continuation or initiation of pulmonary vasodilator therapy. Sildenafil (20–40 mg PO TDS; PBS Authority Required for PAH) and inhaled iloprost are the most commonly used agents in Australian practice. Intravenous epoprostenol (prostacyclin) is reserved for refractory cases and requires central venous access. Bosentan and macitentan are endothelin receptor antagonists with known teratogenicity and are generally avoided.

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Sildenafil

Viagra®, generic · PDE-5 inhibitor

Adult dose 20 mg PO TDS (PAH dosing)

Route / Frequency Oral, three times daily

Pregnancy Category B1 — generally considered acceptable in PAH

Renal adjustment Dose reduction if eGFR <30 mL/min

PBS status Authority Required (PAH)

Eisenmenger Syndrome

Eisenmenger syndrome — irreversible pulmonary hypertension with reversal of shunt flow through a large intracardiac or great vessel defect — is associated with maternal mortality of 30–50%. Death typically occurs peripartum or in the early postpartum period from progressive right heart failure, hypoxaemia, thromboembolism, or paradoxical embolism. Pregnancy is formally contraindicated (mWHO IV).

If pregnancy proceeds despite counselling, management mandates admission to a tertiary centre from 20 weeks gestation. Therapeutic strategies include supplemental oxygen to maintain SpO₂ >90%, avoidance of dehydration and systemic vasodilatation, prophylactic anticoagulation (LMWH from second trimester), and planned early delivery by Caesarean section under epidural or combined spinal-epidural anaesthesia with invasive haemodynamic monitoring.

Hypertrophic Obstructive Cardiomyopathy (HOCM)

HOCM is the most common genetic cardiomyopathy, affecting approximately 1 in 500 individuals. Pregnancy is generally well tolerated in asymptomatic or mildly symptomatic patients (mWHO II), but women with significant left ventricular outflow tract (LVOT) obstruction (gradient >30 mmHg), NYHA III–IV symptoms, or prior arrhythmia are at higher risk (mWHO II–III).

The fall in systemic vascular resistance during pregnancy can worsen dynamic LVOT obstruction. Additionally, the increased venous return and heart rate in labour may trigger haemodynamic deterioration.

Key management principles:

Beta-blockers are first-line: metoprolol 25–100 mg PO BD or propranolol 20–40 mg PO TDS (both Pregnancy Category C — generally acceptable with monitoring).
Maintain adequate preload — avoid dehydration, vasodilatation, and Valsalva manoeuvre.
Vaginal delivery with assisted second stage (forceps/vacuum) is preferred to avoid prolonged pushing.
Epidural analgesia must be used cautiously — low-dose incremental technique with phenylephrine (100 mcg IV bolus) available to counteract hypotension. Avoid pure beta-agonists (e.g., ephedrine) which increase contractility and worsen LVOT obstruction.
ICD or pacemaker in situ: no contraindication to vaginal delivery; magnet available at delivery for ICD deactivation during labour.

Other High-Risk Lesions

Condition	mWHO Class	Key Risk	Management Focus
Severe mitral stenosis (area <1.0 cm²)	III–IV	Pulmonary oedema, AF	Beta-blocker, balloon valvuloplasty if feasible pre-pregnancy
Marfan syndrome (aortic root >40 mm)	III	Aortic dissection	Beta-blocker, serial echo, delivery by Caesarean if aorta >45 mm
Coarctation of aorta (repaired)	II–III	Aortic dissection, re-coarctation	MRI pre-pregnancy, BP control with labetalol
Mechanical valve	III	Valve thrombosis, warfarin embryopathy	Complex anticoagulation (see below)
Systemic RV (e.g., TGA post-Mustard/Senning)	III	RV failure, arrhythmia	Echo monitoring, low threshold for early delivery

Management Principles & Anticoagulation in Pregnancy

General Management Principles

The foundation of managing cardiac disease in pregnancy is preconception risk assessment, shared decision-making, and structured multidisciplinary care. The following principles apply across all cardiac conditions:

Preconception counselling: Discuss mWHO class, maternal and foetal risks, medication adjustments, and delivery planning before conception where possible.
Medication review: Discontinue teratogens (ACE inhibitors, ARBs, statins, amiodarone, direct renin inhibitors). Substitute with pregnancy-safe alternatives (labetalol, hydralazine, nifedipine for hypertension; sotalol or flecainide for arrhythmias where indicated).
Monitoring schedule: Clinical review every 2–4 weeks (mWHO I–II) or weekly (mWHO III–IV). Echocardiography each trimester at minimum — more frequent if valve disease, cardiomyopathy, or aortopathy.
Delivery planning: Planned delivery at 37–39 weeks for most conditions; earlier if haemodynamic deterioration. Written delivery plan reviewed by all team members.
Mode of delivery: Vaginal delivery is preferred for the majority of cardiac conditions. Indications for Caesarean section include obstetric indications, acute haemodynamic instability, severe aortopathy (aortic diameter >45 mm in Marfan), and some complex CHD.
Intrapartum monitoring: Continuous telemetry, pulse oximetry, and invasive arterial monitoring for mWHO III–IV. Pulmonary artery catheterisation reserved for severe pulmonary hypertension or complex haemodynamics.
Postpartum: Monitor in high-dependency for ≥48 hours (mWHO III–IV). Risk of decompensation persists for 3–6 months postpartum due to ongoing haemodynamic changes and fluid redistribution.

Teratogenic Medications to Discontinue

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ACE inhibitors (enalapril, perindopril, ramipril) — renal agenesis, oligohydramnios
ARBs (valsartan, irbesartan, candesartan) — similar to ACEi
Statins (atorvastatin, rosuvastatin) — skeletal anomalies (contraindicated in pregnancy)
Amiodarone — foetal thyroid dysfunction, growth restriction
Direct renin inhibitors (aliskiren) — contraindicated
Eplerenone, spironolactone — anti-androgenic effects
Warfarin — switch to LMWH between 6–12 weeks and from 36 weeks (see anticoagulation below)

Pregnancy-Safe Alternatives

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Labetalol

Trandate® · Alpha/beta-blocker

Adult dose 100–400 mg PO BD–TDS; IV 20 mg bolus then 1–2 mg/min infusion

Pregnancy Category C — widely used, preferred antihypertensive in pregnancy

Renal adjustment No adjustment required

PBS status ✔ PBS General Benefit

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Hydralazine

Alphapress® · Vasodilator

Adult dose 25–50 mg PO TDS; IV 5–10 mg bolus q20min

Pregnancy Category C — safe in pregnancy; avoid in severe aortic stenosis

PBS status ✔ PBS General Benefit

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Nifedipine MR

Adalat® · Calcium channel blocker

Adult dose 30–60 mg PO daily (modified-release)

Pregnancy Category C — safe; avoid immediate-release formulations

PBS status ✔ PBS General Benefit

Anticoagulation in Pregnancy

Pregnancy is a prothrombotic state with a 4–5-fold increased risk of venous thromboembolism (VTE). Anticoagulation management is particularly complex in women with mechanical heart valves, atrial fibrillation, previous VTE, or pulmonary hypertension.

Indication	First-Line Agent	Dose & Monitoring	Key Considerations
Mechanical heart valve	Warfarin or LMWH	LMWH: enoxaparin 1 mg/kg BD + anti-Xa 4h post-dose (target 0.8–1.2 IU/mL) Warfarin: ≤5 mg/day if used in 2nd/3rd trimester	Warfarin embryopathy risk if >5 mg/day in 1st trimester. Switch to LMWH 6–12 weeks then revert. Switch back to LMWH from 36 weeks.
Atrial fibrillation (non-valvular)	LMWH or aspirin	Enoxaparin 1 mg/kg OD–BD (risk-stratified)	DOACs (apixaban, rivaroxaban, edoxaban) contraindicated in pregnancy
VTE prophylaxis	LMWH	Enoxaparin 40 mg OD	Weight-adjust if BMI >40 or renal impairment
VTE treatment	LMWH	Enoxaparin 1 mg/kg BD	Continue for duration of pregnancy + 6 weeks postpartum

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Enoxaparin

Clexane® · LMWH

Treatment dose 1 mg/kg SC BD

Prophylactic dose 40 mg SC OD (20 mg OD if <50 kg)

Monitoring Anti-Xa level 4h post 3rd dose; repeat with weight change >10%

Renal adjustment Reduce dose or switch to UFH if eGFR <30 mL/min

Pregnancy Category C — does not cross placenta

PBS status ✔ PBS General Benefit

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Warfarin

Marevan® · Vitamin K antagonist

Dose Variable; INR target 2.0–3.0 (AF) or 2.5–3.5 (mechanical aortic valve)

Pregnancy Category D — teratogenic 6–12 weeks; risk of foetal haemorrhage near term

Switch protocol LMWH 6–12 weeks → Warfarin 12–36 weeks → LMWH 36 weeks to term

PBS status ✔ PBS General Benefit

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DOACs contraindicated in pregnancy: Apixaban (Eliquis®), rivaroxaban (Xarelto®), edoxaban (Lixiana®), and dabigatran (Pradaxa®) are not recommended in pregnancy due to insufficient safety data and evidence of placental transfer. Use LMWH as the primary anticoagulant.

Peripartum Cardiomyopathy (PPCM)

Peripartum cardiomyopathy (PPCM) is defined as heart failure occurring in the last month of pregnancy or within five months postpartum, with no identifiable cause and no pre-existing cardiac disease, and left ventricular ejection fraction (LVEF) <45% on echocardiography. The incidence in Australia is approximately 1 in 1,000–4,000 live births, with higher rates in Aboriginal and Torres Strait Islander women, women over 30 years, multiparous women, twin pregnancies, and those with pre-eclampsia or gestational hypertension.

Pathophysiology

The pathogenesis is multifactorial. Current evidence supports a "two-hit" hypothesis: (1) the haemodynamic stress of pregnancy on the myocardium, and (2) a prolactin-mediated vascular insult. Upregulated cathepsin D cleaves prolactin into a 16-kDa fragment (vasoinhibin) that is cardiotoxic and anti-angiogenic. Oxidative stress, inflammation, and autoimmune mechanisms also contribute. Selenoprotein deficiency has been implicated in some populations, notably in parts of Africa and potentially among nutritionally at-risk populations in Australia.

Clinical Presentation

Dyspnoea, orthopnoea, paroxysmal nocturnal dyspnoea
Peripheral oedema (may be confused with normal pregnancy changes)
Palpitations, chest discomfort
Cough, haemoptysis (severe cases)
Thromboembolism — stroke, peripheral arterial embolism (up to 5–7% incidence due to low EF and hypercoagulable state)

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Diagnostic pitfall: Symptoms of PPCM (dyspnoea, oedema, fatigue) overlap significantly with normal third-trimester physiology. A high index of suspicion and a low threshold for echocardiography is essential in any peripartum woman with disproportionate or persistent symptoms.

Diagnostic Criteria

Heart failure in the last month of pregnancy or within 5 months postpartum
LVEF <45% on echocardiography (or fractional shortening <30%)
No other identifiable cause of heart failure
No pre-existing cardiac disease

Management of PPCM

Management follows standard heart failure principles with important modifications for pregnancy and lactation safety.

If presenting antenatally:

Diuretics: Furosemide 20–40 mg PO/IV OD–BD (Category C, generally acceptable). Avoid excessive diuresis to maintain placental perfusion.
Vasodilators: Hydralazine 25–50 mg PO TDS + isosorbide dinitrate 10–20 mg PO TDS (safe in pregnancy). Avoid ACEi/ARBs until after delivery.
Beta-blockers: Carvedilol 3.125–25 mg PO BD or metoprolol 25–100 mg PO BD (Category C). Initiate cautiously; avoid in acute haemodynamic instability.
Anticoagulation: LMWH if LVEF <35% due to high thromboembolic risk.
Delivery: Expedite delivery if LVEF <30% or NYHA III–IV despite therapy. Vaginal delivery preferred.

If presenting postpartum:

ACE inhibitor: Enalapril 2.5–20 mg OD or perindopril 2–8 mg OD (compatible with breastfeeding; preferred).
Beta-blocker: Carvedilol or metoprolol as above.
Diuretics: Furosemide as needed for congestion.
Mineralocorticoid receptor antagonist: Spironolactone 25 mg OD if LVEF <35% (compatible with breastfeeding).
Anticoagulation: Warfarin or LMWH if LVEF <35%.
Bromocriptine: 2.5 mg PO BD for 2 weeks, then 2.5 mg daily for a further 4–6 weeks. Targets the prolactin-mediated pathway. The BRO-HF and another pilot trial showed improved LV recovery. Note: Bromocriptine suppresses lactation — combined with ACEi use, breastfeeding is generally not supported if bromocriptine is given.

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Bromocriptine

Parlodel® · Dopamine agonist

PPCM dose 2.5 mg PO BD × 2 weeks, then 2.5 mg OD × 4–6 weeks

Route / Frequency Oral, twice daily initially

Key side effects Nausea, headache, dizziness, VTE risk (add LMWH prophylaxis)

Pregnancy Category B3 — used postpartum in PPCM

PBS status ✔ PBS General Benefit

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Carvedilol

Dilatrend® · Alpha/beta-blocker

Dose 3.125 mg PO BD, titrate to 25 mg BD as tolerated

Pregnancy Category C — use with monitoring

PBS status ✔ PBS General Benefit

Prognosis

Recovery (LVEF ≥50%) occurs in approximately 50–70% of women with PPCM, typically within 6–12 months. Factors associated with poor recovery include LVEF <25% at diagnosis, LV end-diastolic diameter >60 mm, African ancestry (higher incidence and worse outcomes), and delayed presentation. Relapse occurs in 20–30% of subsequent pregnancies, and subsequent pregnancy is contraindicated if LVEF has not recovered to ≥50%.

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Subsequent pregnancy contraindicated if LVEF <50%: Women with persistent LV dysfunction must be counselled that further pregnancy carries a significant risk of irreversible heart failure and death. Reliable long-term contraception (LARC preferred) is essential.

Risk Stratification: Modified WHO Classification

The modified WHO (mWHO) classification is the most widely validated risk assessment tool for cardiac disease in pregnancy and is recommended by the European Society of Cardiology (ESC) and endorsed by the Cardiac Society of Australia and New Zealand (CSANZ).

Low Risk

mWHO Class I

Uncomplicated small or mild PS, mild PDA, MVP without significant MR, repaired ASD/VSD/PDA without residua

Setting: May be managed in a facility with obstetric and basic medical services

Moderate Risk

mWHO Class II–II/III

Unrepaired ASD/VSD, repaired TOF, mild LV dysfunction (EF 40–49%), HOCM, Marfan (aorta <40 mm), mechanical aortic valve (bileaflet with warfarin <5 mg)

Setting: Tertiary hospital with cardiac and obstetric services

High Risk

mWHO Class III

Mechanical valve (warfarin >5 mg), moderate LV dysfunction (EF 30–39%), severe mitral/aortic stenosis, systemic RV, Marfan (aorta 40–45 mm), Fontan circulation

Setting: Tertiary centre with cardiac surgery, ICU, and expert cardio-obstetric team

Extreme Risk

mWHO Class IV (Contraindicated)

Pulmonary arterial hypertension (any cause), Eisenmenger syndrome, severe systemic ventricular dysfunction (EF <30%), severe symptomatic AS/MS, Marfan (aorta >45 mm), peripartum cardiomyopathy with residual LV dysfunction

Setting: Pregnancy contraindicated — if proceeding, highest-level tertiary care with cardiac surgery, ECMO capability, and ICU

Special Populations

🤰 Pregnancy Considerations

Medication safety: All cardiac medications require pregnancy category review. Use BNF/pregnancy safety databases and consult maternal-fetal medicine.

Imaging: Echocardiography is safe in all trimesters. Cardiac MRI (without gadolinium) can be used after the first trimester if diagnostic benefit outweighs theoretical risk. CT pulmonary angiography is indicated for suspected PE with appropriate shielding and lowest-dose protocol.

Foetal monitoring: Growth scans from 28 weeks if maternal cardiac output compromised. Continuous foetal monitoring in labour for mWHO ≥ III.

👶 Neonatal Considerations

Beta-blocker exposure: Neonatal bradycardia, hypoglycaemia — monitor for 24–48 hours post-delivery.

Warfarin exposure: Risk of foetal haemorrhage; plan delivery with neonatal team and vitamin K available.

Prematurity: Increased in mWHO III–IV; steroids for foetal lung maturity as per standard obstetric protocols.

👵 Advanced Maternal Age

Risk: Women >35 years have higher baseline cardiovascular risk. Pre-pregnancy cardiac assessment is recommended, particularly for women with hypertension, diabetes, or family history of cardiomyopathy/aortopathy.

IVF: Ovarian hyperstimulation syndrome (OHSS) can precipitate heart failure in women with borderline cardiac function. Pre-IVF cardiac assessment is advised.

🫘 Renal Impairment

Anticoagulation: Enoxaparin dose adjustment required if eGFR <30 mL/min — consider unfractionated heparin with APTT monitoring.

Diuretics: Reduced efficacy in advanced renal disease; may require combination therapy.

🛡️ Autoimmune & Connective Tissue Disease

SLE: Lupus-related valve disease, Libman-Sacks endocarditis, and antiphospholipid-associated thrombosis are important considerations. Anti-Ro/La antibodies require foetal cardiac monitoring (foetal echocardiography at 16 and 28 weeks) for congenital heart block risk.

Antiphospholipid syndrome: Therapeutic LMWH (enoxaparin 1 mg/kg BD) + low-dose aspirin (100 mg OD) throughout pregnancy.

Aboriginal and Torres Strait Islander Health Considerations

Aboriginal and Torres Strait Islander Health

Aboriginal and Torres Strait Islander women experience significantly higher rates of cardiac disease in pregnancy compared with non-Indigenous Australians, driven primarily by the burden of rheumatic heart disease (RHD). RHD remains the most common acquired heart disease in pregnancy among Indigenous Australians, particularly in Northern Territory, Western Australia, and Far North Queensland communities.

Rheumatic heart disease burden

RHD notification rates in Aboriginal and Torres Strait Islander peoples are 60–80 times higher than non-Indigenous Australians. Acute rheumatic fever (ARF) predominantly affects young people, leading to significant valvular disease — especially severe mitral regurgitation and stenosis — by reproductive age.

Delayed diagnosis

Aboriginal and Torres Strait Islander women may present later in pregnancy with undiagnosed cardiac disease. Murmurs attributed to benign flow may mask significant valvular pathology. Systematic cardiac screening (clinical examination + echocardiography if murmur detected) should be integrated into antenatal care in high-prevalence regions.

Geographic barriers

Many women in remote communities are far from tertiary cardiac and obstetric services. Retrieval and aeromedical transfer capabilities are essential. Pre-planned delivery evacuation — typically at 36–37 weeks — is required for women with mWHO III–IV conditions living remotely.

Secondary prophylaxis

Adherence to secondary prophylaxis with benzathine penicillin G (BPG) 1.2 MU IM every 21 days is critical in women with RHD. Pregnancy does not contraindicate BPG. Non-adherence is common due to pain, side effects, and geographic access — nurse-administered injection programmes and community health worker engagement improve completion rates.

Peripartum cardiomyopathy

Emerging data suggest higher incidence and worse outcomes of PPCM in Indigenous Australian women, potentially linked to nutritional deficiency (selenium, iron), higher rates of pre-eclampsia, and delayed presentation. Enhanced postpartum follow-up is recommended.

Culturally safe care

Engagement of Aboriginal Health Workers and Liaison Officers (AHWLOs) in the antenatal and intrapartum team improves communication, trust, and outcomes. Family-centred care models, language-appropriate education materials, and acknowledgement of kinship obligations are essential. Interpreter services should be offered for women whose first language is not English.

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Resource: The RHD Australia (RHDAustralia) guidelines provide specific recommendations for ARF/RHD management in pregnancy, including echocardiographic surveillance schedules and penicillin prophylaxis protocols. Refer to: RHDAustralia ARF/RHD writing group. The 2020 Australian guideline for prevention, diagnosis, and management of acute rheumatic fever and rheumatic heart disease (3rd edition).

📚 References

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