Cardiac case panel: Sarah’s murmur is a bicuspid valve — and the aorta is part of the disease
Interactive QCG panel: differential for an ejection systolic murmur in a 37-year-old, why “asymptomatic” is unreliable, pregnancy WHO class III counselling at 4.6 cm ascending aorta, endocarditis rules, and mechanical vs bioprosthetic choice at 42.
- Panel chair / case presenter
- QCG host walking the “Sarah” case (ASR first name unclear in places; same weekend faculty as imaging / ACHD panels).
- Panel
- Dr Scott McKenzie (ASR: Scott) — wide differential, metabolic phenotype, “truly asymptomatic?” probing, stimulants/ADHD risk comments.
- Dr Mona Lewin (ASR: Mona) — ACHD / bicuspid-aortopathy framing, pregnancy mWHO class III counselling, endocarditis prophylaxis niche, MRI preference in young patients.
- Dr Nikki Mai (ASR: imaging voice; echo/ECG first steps, CT vs echo measurement scatter) — same imaging lead as the diastolic talk.
- Audience / floor: Alex (CPD logistics), Jeff and others — ADHD stimulants, exercise in aortopathy, BP agent preference.
- Session context
- Otter id
yEmFIBMoeaxZd5tyotF-EPjq7J0· title Cardiac Case Panel Review · ~35.1 min (2107 s) · 2026-02-28. Companions: diastolic-dysfunction · cardiology-subspecialties · high-risk-pregnancy.
Key messages for GPs
- Young woman + right-upper-sternal murmur → think bicuspid aortic valve first among congenital causes; keep HOCM, pulmonary stenosis, VSD, coarctation/collaterals on the list.
- Do not trust “asymptomatic” in lifelong gradual disease — exercise-test or carefully tease functional limits (stairs, carrying shopping, walking pace vs peers).
- BAV is not isolated leaflet disease — screen/measure the ascending aorta; echo thresholds (~4 cm discussed) are moving toward height-indexing; confirm borderline sizes with CT/MRI.
- Ascending aorta ~4.6 cm + desire for another pregnancy → shared decision; panel framed mWHO class III (~up to ~30% CV event risk in pregnancy including dissection risk) vs operating first (mechanical valve → anticoagulation also ~class III).
- Native moderate BAV/AS: routine IE prophylaxis not recommended in current guidance as stated; prosthetic/mechanical valves need high-risk dental cover (amoxicillin 3 g 1 h pre — ESC framing in the room; check Australian TG).
- Lost to follow-up + severe AS + 5 cm aorta → operate; valve choice in a 42-year-old is shared decision (mechanical longevity vs warfarin lifestyle).
Meet Sarah
37-year-old referred with a newly detected cardiac murmur at the right upper sternal border. Background: endometriosis, ADHD on dexamfetamine (ASR: “dexamethadine”), PCOS, gout history, previous right-mainstem hospital issues (ASR unclear), gestational diabetes in both pregnancies. Family: healthy children; maternal-line breast cancer cluster; cousin with “wishy-washy” ischaemic heart disease and nonspecific bowel problems.
Metabolic context matters: PCOS + GDM = accelerated atherosclerotic risk phenotype — Scott flags she is not a “low-risk young woman” even before valve disease is sorted.
Murmur differential
Panel walk-through for an ejection/systolic murmur in this age group:
- Bicuspid aortic valve (Mona: top of the congenital list; degenerates by 30s–40s).
- HOCM / dynamic LVOT obstruction (loudness/manoeuvres).
- Mitral regurgitation (if not clearly ejection systolic).
- Pulmonary / supravalvular stenosis (Williams mentioned); membranes / subvalvular lesions.
- Coarctation — murmurs from collaterals; venous collaterals in complex ACHD.
- VSD can mimic “classic AS” on auscultation alone — keep the differential wide.
Exam clues rehearsed: soft S2, splitting, S4, pulse pressure, plus red-flag symptoms — exertional dyspnoea, angina, exertional syncope/presyncope.
“Asymptomatic” is a spectrum
Sarah is labelled asymptomatic — the panel pushes back hard. Congenital/progressive lesions condition people to a lower ceiling for decades. Ask partners about walking pace; ask about carrying shopping upstairs; consider formal exercise testing or even respiratory VO₂ referral when under-reporting is suspected (Mona). Metabolic syndrome / ADHD stimulants can also muddy the symptom story (Scott).
Bicuspid valve = aortopathy mindset
Echo result in the case: parameters of moderate aortic stenosis, bicuspid morphology with right–left cusp raphe (type 1), no LVH, EF 62%, mild AR. Ascending aorta visible at 4.6 cm; root ~4.1 cm. Host notes echo “clear-cut” concern around 4 cm, with a shift toward height-indexing rather than BSA (obesity/body-size distortion).
Haemodynamic assessment is similar, but BAV is a systemic aortopathy — ascending aorta dilatation is common (vs genetic aortopathies that more often hit the root — Mona linking to her earlier Loeys–Dietz case). Young patients force timing decisions around sport, pregnancy and mechanical vs bio valves.
Epidemiology quoted: BAV ~1–2% of the population — commonest congenital heart lesion. Family screening: offer echo to first-degree relatives at some point in life; most BAV is not clearly Mendelian, though NOTCH2-associated families exist — routine genetic testing not standard; Medicare rebate for that gene pathway discussed as limited in Australia (panel uncertainty).
Lifestyle: avoid heavy isometric / high-resistance loading if aorta dilated; optimise BP (beta-blocker / ARB discussed as possible dilatation-slowing tools — evidence “not super strong,” mechanism largely BP). Surveillance for moderate AS: at least within the first 12 months, then typically every 1–2 years if stable — faster if progression suspected.
Pregnancy at 4.6 cm
Sarah wants another baby. Mona’s counselling frame:
- Outside pregnancy, 4.6 cm ascending aorta with BAV would usually mean imaging surveillance, not automatic surgery — rate of growth and BP control matter.
- In modified WHO pregnancy risk: aorta at this size pushed into class III — quoted up to ~30% cardiovascular event risk including dissection risk; class IV would be “do not get pregnant / terminate” territory.
- Path A: continue with informed consent, frequent echo (every few weeks cited), accept possible need to operate in pregnancy (fetal risk on bypass).
- Path B: replace valve ± ascending aorta first — but a mechanical valve puts her on anticoagulation, also roughly class III (~27% event risk framed in the talk).
No single “right” answer in class III — geography (can she attend fortnightly imaging?), tolerance of dissection risk, and anticoagulation lifestyle all decide. Document the conversation.
Endocarditis prophylaxis
| Situation | Panel take |
|---|---|
| Native BAV with moderate AS | Routine dental IE prophylaxis not recommended on current guidance as stated; prior proven IE → treat as high risk thereafter. |
| Everyday prevention | Excellent dental hygiene, regular dentist, avoid non-sterile piercings/tattoos; treat skin infections early and firmly. |
| Mechanical / prosthetic valve | Prophylaxis for high-risk dental work (gingival manipulation / bleeding). Mona: amoxicillin 3 g one hour pre (ESC table); alternatives if allergic. Bio prosthesis: cover first 6 months; after 6 months if no significant residual lesion, routine prophylaxis may stop (as stated). |
| Cautionary tale | 14-year-old with mild BAV stenosis — endocarditis after brushing/angry gums discussion; multiple early bioprosthetic failures in a high-output adolescent — counsel durability honestly. |
Always cross-check Therapeutic Guidelines / CSANZ for Australian practice — panel referenced both ESC and TG access.
Five years on: surgery & valve choice
Lost to follow-up, returns breathless: harsh ESM radiating to carotids, severe bicuspid AS, concentric LVH/remodelling, more AR, ascending aorta 5 cm — clear surgical case. At 42, no further pregnancy planned: historical default mechanical (± root/ascending replacement) for longevity; growing discussion of bioprosthesis with future TAVI-in-valve — still a moving space for this age. Shared decision must include warfarin lifestyle.
Floor Q&A (compressed): ADHD stimulants — watch BP/HR; real-world concern in older/metabolically ill patients despite early literature; no clear data that dexamfetamine accelerates BAV stenosis via shear. Exercise with dilated aorta — avoid heavy isometric loads (firefighter/weightlifting example). Incidental hypertension — ARBs often preferred over beta-blockers for aortopathy BP work when a choice exists (Scott: trial data for beta-blockers “not impressive”).
Clinic checklist
- Young adult murmur → ECG + echo; report must comment on aortic dimensions.
- BAV on letter → measure/confirm aorta; offer first-degree relative screening echo; lifestyle + BP plan.
- Challenge “asymptomatic”; refer cardiology early if pregnancy is on the table and aorta ≥~4.5 cm.
- IE advice: hygiene first; know prosthetic vs native rules; give a pre-dental script when indicated.
- Never let moderate AS + dilated aorta disappear from recall — five-year gap in this case ends in theatre.