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Inherited Cardiac Conditions reference

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Marfan Syndrome

Quick Summary

Definition: A systemic autosomal dominant connective tissue disorder caused by FBN1 variants, with skeletal, ocular and cardiovascular features, notably aortic root dilatation and dissection risk.[1]

  • Prevalence: 1 in 5,000 (most common heritable aortopathy)[1]
  • Key gene: FBN1 (fibrillin-1), autosomal dominant, ~25% de novo
  • Hallmark: Aortic root dilatation (Z≥2) + ectopia lentis + skeletal features (Ghent criteria)
  • High-risk markers: Aortic root >45mm, rapid growth (>3mm/year), family history dissection, pregnancy
  • First-line Mx: Beta-blockers (target HR 60-70), annual echo, prophylactic surgery >50mm (or >45mm if risk factors)

Aetiology

Monogenic (Mendelian): ~100%, FBN1 variant (~25% de novo)[1]

Genetics

Inheritance: Autosomal dominant; first-degree relatives have a 50% risk of inheriting the pathogenic variant.[1]

Familial vs de novo: Approximately 75% of cases are familial (inherited from an affected parent); approximately 25% arise as de novo FBN1 mutations with no family history of Marfan syndrome.[1]

Gene: FBN1 (fibrillin-1), >90% of cases meeting revised Ghent criteria

Penetrance: ~100%, but expressivity is highly variable, the same mutation can cause mild or severe disease even within the same family

Prevalence

1 in 5,000 to 1 in 10,000[1]

No ethnic or sex predilection

~25% de novo mutations

Diagnostic Criteria

Revised Ghent Nosology (2010)

In absence of family history:

  • Aortic root dilatation (Z-score ≥2) AND ectopia lentis, OR
  • Aortic root dilatation AND FBN1 mutation, OR
  • Aortic root dilatation AND systemic score ≥7, OR
  • Ectopia lentis AND FBN1 mutation with known aortic disease

With family history:

  • Ectopia lentis, OR
  • Systemic score ≥7, OR
  • Aortic root dilatation (Z ≥2 if age ≥20y, Z ≥3 if <20y)

Diagnosis

Confirming the diagnosis (revised Ghent nosology[1]): with no family history, diagnosis needs aortic root Z-score ≥2 (or dissection) plus ectopia lentis, or aortic root involvement plus a causative FBN1 variant, or a systemic score ≥7 with aortic involvement. Ectopia lentis with a known aortic-associated FBN1 variant also confirms it. Mandatory work-up: echocardiography (aortic root Z-score), slit-lamp ophthalmology (ectopia lentis), and FBN1 genetic testing for confirmation and family cascade.

Cardinal cardiovascular features:

  • Aortic root aneurysm (most important - risk of dissection)
  • Aortic regurgitation
  • Mitral valve prolapse, mitral regurgitation
  • Aortic dissection

Skeletal features: Tall stature, arachnodactyly, pectus deformity, scoliosis, reduced upper:lower segment ratio

Ocular: Ectopia lentis (lens dislocation)

Investigations

Echocardiography: Aortic root dimensions at sinuses of Valsalva (use Z-scores for age/BSA), annually[2]

CT/MR angiography: Full aortic imaging at baseline and follow-up; required if echo suboptimal[2]

Genetic testing: FBN1 sequencing; multi-gene panel (including FBN2, TGFBR1/2) if FBN1-negative[1]

Ophthalmology: Slit-lamp examination for ectopia lentis

Treatments

Medical therapy, reduce aortic growth rate (ESC 2014 Aortic Guidelines[2]):

1. Beta-blockers (first-line)

  • Atenolol (most evidence in Marfan; the Pediatric Heart Network trial found atenolol and losartan similarly effective at slowing aortic-root dilatation in children and young adults[7]):
    • Start 25–50 mg once daily → target 50–100 mg once daily
    • Target resting HR <60–70 bpm and blunted exercise HR response
    • Dose to maximum tolerated; avoid underdosing
  • Bisoprolol (alternative):
    • Start 2.5 mg once daily → target 5–10 mg once daily
    • Preferred if atenolol not tolerated or renal impairment
  • Propranolol (alternative, non-selective):
    • Start 20–40 mg twice daily → target 80–160 mg twice daily

2. Losartan, additive to beta-blocker (ESC Class IIa)

  • Start 25–50 mg once daily → target 100 mg once daily (or maximum tolerated)
  • COMPARE trial: losartan reduced the aortic-root dilatation rate in adults with Marfan syndrome[8]. The AIMS trial separately found irbesartan slowed aortic-root dilatation in children and young adults[9]. Overall, ARBs and beta-blockers each modestly slow aortic growth, with no clear superiority of one class
  • Avoid in pregnancy, switch to beta-blocker monotherapy pre-conception
  • Monitor K⁺ and renal function; check BP (target systolic <130 mmHg)

Surgical intervention:

  • Prophylactic aortic root replacement if diameter ≥50 mm (≥45 mm if family history of dissection, rapid growth >3 mm/year, or concurrent surgery planned)[2][6]
  • Valve-sparing root replacement (David/Yacoub procedure) preferred if aortic valve pliable and not regurgitant

Lifestyle:

  • Avoid heavy lifting, isometric exercise, contact sports, competitive sports
  • Moderate aerobic activity (low-intensity) generally acceptable
Related Resources

Complications

  • Aortic root aneurysm: progressing to dissection or rupture, the principal life-threatening complication[1]
  • Aortic and mitral regurgitation: and mitral valve prolapse
  • Pregnancy-associated dissection: with risk rising with root size and in the peripartum period
  • Multisystem features: ectopia lentis and retinal detachment, spontaneous pneumothorax, dural ectasia and scoliosis

Risk Stratification

Aortic dissection risk increases with: Diameter >50mm, rapid growth (>3mm/year), family history dissection

Life expectancy: Near normal with appropriate management

Pregnancy Management

ESC 2018 Pregnancy Guidelines - Marfan Syndrome (mWHO Class II-IV)

PRECONCEPTION COUNSELLING - MANDATORY:

  • Risk stratification by aortic root diameter:
    • Aortic root <40mm: mWHO II (low-moderate risk) - pregnancy generally safe
    • Aortic root 40-45mm: mWHO III (high risk) - pregnancy possible with very close monitoring
    • Aortic root >45mm: mWHO IV (extremely high/contraindicated) - PREGNANCY CONTRAINDICATED
    • Prior aortic dissection: mWHO IV - PREGNANCY CONTRAINDICATED
    • Rapid aortic growth (>3mm/year): mWHO IV - consider dissection risk too high
  • Maternal mortality risk:
    • Aortic root <40mm: ~1% (mostly if rapid growth during pregnancy)
    • Aortic root 40-45mm: ~5-10%
    • Aortic root >45mm: ~10-20% (aortic dissection risk)
    • 50% of Marfan-related maternal deaths occur with aortic root >40mm
  • Mandatory baseline imaging:
    • Transthoracic echo (aortic root, ascending aorta dimensions at sinuses, sinotubular junction, ascending aorta)
    • CT/MR angiography - FULL aortic imaging (root to iliac bifurcation)
    • Assess ascending and descending thoracic aorta, arch
    • Document baseline dimensions precisely
  • Consider prophylactic surgery BEFORE pregnancy if:
    • Aortic root 45-50mm (ESC threshold for intervention)
    • Family history of dissection at smaller diameters
    • Rapid aortic growth (>3mm/year)
    • Allow 6-12 months post-surgery before conception
  • Medications:
    • Beta-blockers: Continue throughout (metoprolol, labetalol, atenolol safe)
    • ACE inhibitors/ARBs: STOP before conception (teratogenic) - switch to beta-blocker
    • Losartan: Limited pregnancy data - discontinue
  • Genetic counselling:
    • Autosomal dominant: 50% transmission risk
    • Prenatal testing available (chorionic villus sampling, amniocentesis)
    • Offspring management: Echo at birth, repeat age 5, then 5-yearly until growth complete

PREGNANCY MANAGEMENT:

  • Monitoring frequency (aortic root <40mm):
    • Cardiology review + echo MONTHLY throughout pregnancy
    • More frequent if any aortic growth detected
  • Monitoring frequency (aortic root 40-45mm):
    • Cardiology review + echo EVERY 4 WEEKS
    • Weekly in 3rd trimester
    • CT/MR aortography each trimester (full aorta assessment)
  • Beta-blocker therapy - ESSENTIAL:
    • Continue throughout pregnancy at maximum tolerated dose
    • Target resting heart rate 60-70 bpm (reduce aortic wall stress)
    • Metoprolol 50-200mg/day OR atenolol 50-100mg/day OR labetalol 200-400mg BD
    • NEVER stop beta-blockers - risk of rebound tachycardia and increased wall stress
  • Aortic growth monitoring:
    • Aortic root typically enlarges ~1-2mm during pregnancy (hormonal + volume effects)
    • Growth >3mm OR rate >1mm/month = HIGH RISK
    • If rapid growth: Increase echo frequency, consider early delivery
  • Activity restriction:
    • Avoid strenuous physical activity, heavy lifting, Valsalva maneuvers
    • Gentle walking acceptable
    • Avoid contact sports, high-impact activities
  • Red flags - URGENT assessment:
    • Chest pain, back pain, abdominal pain (dissection symptoms)
    • Sudden onset severe pain (tearing/ripping quality)
    • Syncope, neurological symptoms
    • → CT aortography immediately; consider dissection until proven otherwise

LABOUR & DELIVERY:

  • Delivery planning:
    • Mandatory delivery at tertiary centre with cardiothoracic surgery on-site
    • MDT planning at 32 weeks (cardiology, obstetrics, cardiac anaesthetics, cardiothoracic surgery)
    • Aim delivery 38-40 weeks if stable
    • Earlier delivery (36-38 weeks) if aortic root >40mm or rapid growth
  • Mode of delivery:
    • Vaginal delivery with assisted second stage (forceps/ventouse): Preferred if aortic root <40mm and stable
    • Elective caesarean section: If aortic root >40mm, rapid aortic growth, or aortic regurgitation
    • Rationale for assisted 2nd stage: Minimize maternal Valsalva/pushing effort (↓ aortic wall stress)
  • Anaesthesia:
    • Epidural strongly preferred: Excellent pain control, reduces catecholamine surge, avoids Valsalva with pushing
    • Early epidural placement (don't wait for advanced labour)
    • General anaesthesia if caesarean: Careful BP control during intubation (avoid hypertensive spike)
    • Target systolic BP <120 mmHg throughout labour/delivery
  • Intrapartum haemodynamic control - CRITICAL:
    • Arterial line (invasive BP monitoring) if aortic root >40mm
    • Target BP: Systolic 100-120 mmHg, avoid >130 mmHg
    • Target HR: 60-80 bpm
    • Continue oral beta-blocker (give with sips water even if NBM)
    • IV labetalol available for BP spikes (5-20mg boluses)
    • Avoid hypotension (placental perfusion) but prioritize aortic protection
  • Monitoring:
    • Continuous ECG, pulse oximetry
    • Arterial line if aortic root >40mm
    • Cardiothoracic surgery team on standby if aortic root >40mm
  • If aortic dissection during labour:
    • Emergency caesarean section + simultaneous aortic repair
    • Perimortem caesarean if maternal cardiac arrest
    • Maternal resuscitation takes priority if viable gestational age not reached

POSTPARTUM:

  • Critical monitoring period (6-8 weeks):
    • Highest dissection risk is first 48 hours postpartum but remains elevated for 6-8 weeks
    • Monitor in HDU/CCU for 24-48 hours if aortic root >40mm
    • Echo at discharge, 2 weeks, 6 weeks postpartum
    • Patient education: Report chest/back pain immediately
  • Aortic regression:
    • Aortic root typically returns to baseline by 6 months postpartum
    • If persistent enlargement: Increased future dissection risk, counsel against further pregnancy
  • Continue beta-blockers:
    • Lifelong therapy recommended
    • Safe with breastfeeding (metoprolol, labetalol preferred)
    • Restart ACE-I/ARB if needed (enalapril compatible with breastfeeding)
  • Contraception:
    • LARC strongly recommended (IUD, implant)
    • Combined oral contraceptive generally avoided (thrombosis risk)
    • Progesterone-only methods safe
    • Female sterilization option if family complete
  • Breastfeeding: Safe and encouraged; beta-blockers compatible
  • Future pregnancies:
    • Reassess aortic dimensions before considering
    • If aortic root increased and not regressed: Counsel AGAINST further pregnancy
    • Ideally wait 12 months between pregnancies (allow full aortic regression)

ABSOLUTE CONTRAINDICATIONS TO PREGNANCY:

  • Aortic root diameter >45mm
  • Previous aortic dissection (any time, any location)
  • Rapid aortic growth >3mm/year
  • Severe aortic regurgitation
  • LV dysfunction (LVEF <40%)

KEY STATISTICS:

  • ~90% of Marfan pregnancies with aortic root <40mm are successful without complications
  • 1% maternal mortality if aortic root <40mm; 10-20% if >45mm
  • Aortic dissection occurs in ~1-3% overall; ~10% if aortic root >40mm
  • Most dissections occur late pregnancy or early postpartum

CRITICAL SUCCESS FACTORS:

  • Pre-pregnancy aortic root assessment and surgical intervention if indicated
  • Monthly aortic imaging throughout pregnancy
  • Beta-blocker therapy throughout pregnancy + lifelong
  • Delivery at specialist centre with cardiothoracic surgery
  • BP control <120/80 mmHg during labour/delivery
  • Assisted second stage or elective CS (avoid maternal Valsalva)
  • Extended postpartum surveillance (dissection risk persists 6-8 weeks)

Follow-up

Based on the 2024 ESC aortic & peripheral arterial diseases (PAAD) guideline and the revised Ghent nosology[2][1][6].

Advanced / complicated = aortic root ≥45 mm, growth >3 mm/year, prior dissection or repair, significant valve disease, or pregnancy.

Genotype-positive / phenotype-negative (G+/P−) = a confirmed pathogenic-variant carrier with no overt disease expression yet.

Genotype+ / Phenotype−Uncomplicated / StableAdvanced / Complicated
FrequencyAnnual (FBN1+ even if no features)AnnualEvery 6 months (or sooner)
Clinical reviewSymptoms, BP control, medicationSymptoms, BP control, medication adherenceAs above
Echocardiography (aortic root)AnnualAnnual if stable and <45 mm6-monthly if ≥45 mm or growing
CT / MR angiography (whole aorta)BaselineBaseline, then every 1–2 yearsAnnual or sooner
Ophthalmology / skeletalPeriodic (ectopia lentis, skeletal)Periodic (ectopia lentis, scoliosis)As needed
PregnancyPre-conception counsellingPre-conception aortic assessment & counsellingMonthly aortic imaging if pregnant
Family screening–Cascade imaging ± genetics–

Disclaimer: This table is general guidance based on published guidelines and does not replace clinical judgement. The responsible clinician is accountable for determining the appropriate, individualised follow-up plan for each patient.

Key Points

  • Lifelong surveillance required - annual imaging[1]
  • Genetic counselling - 50% risk to offspring[1]
  • PREGNANCY CONTRAINDICATED if aortic root >45mm or prior dissection - refer for prophylactic surgery BEFORE conception[1]
  • Aortic root <40mm: mWHO II (pregnancy safe with monthly monitoring); 40-45mm: mWHO III (high risk); >45mm: mWHO IV (contraindicated)
  • Beta-blockers ESSENTIAL throughout pregnancy - target HR 60-70 bpm[1]
  • Delivery at tertiary centre with cardiothoracic surgery on-site
  • Screen first-degree relatives

References & Review Date

Last reviewed: June 2026

  1. Loeys BL, et al. The revised Ghent nosology for the Marfan syndrome. J Med Genet. 2010;47(7):476–485. doi:10.1136/jmg.2009.072785
  2. Erbel R, et al. 2014 ESC Guidelines on the diagnosis and treatment of aortic diseases. Eur Heart J. 2014;35(41):2873–2926. doi:10.1093/eurheartj/ehu281
  3. Milleron O, et al. COMPARE-Marfan trial: losartan versus atenolol on aortic root growth in Marfan syndrome. Eur Heart J. 2015;36(4):216–225. doi:10.1093/eurheartj/ehu334
  4. Regitz-Zagrosek V, et al. 2018 ESC Guidelines for the management of cardiovascular diseases during pregnancy. Eur Heart J. 2018;39(34):3165–3241. doi:10.1093/eurheartj/ehy340
  5. Joint Formulary Committee. British National Formulary (BNF). bnf.nice.org.uk
  6. Mazzolai L, Teixido-Tura G, Lanzi S, et al. 2024 ESC Guidelines for the management of peripheral arterial and aortic diseases. Eur Heart J. 2024;45:3538–3700. doi:10.1093/eurheartj/ehae179
  7. Lacro RV, et al. Atenolol versus losartan in children and young adults with Marfan's syndrome (Pediatric Heart Network). N Engl J Med. 2014;371(22):2061–2071. doi:10.1056/NEJMoa1404731
  8. Groenink M, et al. Losartan reduces aortic dilatation rate in adults with Marfan syndrome (COMPARE): a randomized controlled trial. Eur Heart J. 2013;34(45):3491–3500. doi:10.1093/eurheartj/eht334
  9. Mullen M, et al. Irbesartan in Marfan syndrome (AIMS): a double-blind, placebo-controlled randomised trial. Lancet. 2019;394(10216):2263–2270. doi:10.1016/S0140-6736(19)32518-8