Patient handout

Transthyretin amyloid cardiomyopathy (ATTR-CM, ATTRv + ATTRwt)

PRODUCTION

1. Your condition

This handout is for transthyretin amyloid cardiomyopathy (attr-cm, attrv + attrwt). Your care team identified this based on: hfpef with lv wall thickness ≥12 mm not explained by htn/as.

Other reasons your team may use this plan: low ecg voltage discordant with increased lv wall thickness; bilateral carpal tunnel syndrome / lumbar canal stenosis / biceps rupture (amyloid prodrome); 99mtc-pyp / dpd scintigraphy perugini grade 2–3.

3. When to call your provider

Contact your care team if any of the following happen:

Decompensation → cautious decongestion, amyloid-acute pathway — 2023 ACC amyloid ECDP
High-grade AV block → pacemaker — 2023 ACC amyloid ECDP
Monoclonal protein detected → AL pathway / hematology — Gillmore Circulation 2016

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

Abnormal serum FLC ratio or monoclonal on immunofixation — do NOT diagnose ATTR by PYP; route to AL amyloid / hematology pathway (oncologic) — Gillmore Circulation 2016
Patient on beta-blocker / ACEi-ARB-ARNi / non-DHP CCB / digoxin — deprescribe; standard HFrEF the four foundational heart-failure medications does not apply and CCB/digoxin are toxic in amyloid — 2023 ACC amyloid ECDP
Concomitant severe aortic stenosis + ATTR-CM (ATTR-AS) — TAVR consideration; do not deny intervention for amyloid alone — 2023 ACC amyloid ECDP
AF in ATTR-CM — anticoagulate regardless of CHA₂DS₂-VASc (high intracardiac-thrombus/stroke risk); rate control difficult (avoid BB/non-DHP CCB/digoxin) — 2023 ACC amyloid ECDP
High-grade AV block / progressive conduction disease (amyloid infiltration of conduction system) — pacemaker — 2023 ACC amyloid ECDP
NAC stage III (high natural marker of fluid overload (NT-proBNP) + low eGFR) — TTR-stabiliser benefit attenuated; emphasise symptom control, transplant assessment (young ATTRv), palliative discussion — ATTR-ACT subgroup

5. Follow-up

Family cascade screening (ATTRv); ATTR-AS → TAVR; lifelong amyloid-centre care

6. Sources

Guideline: 2023 ACC Cardiac Amyloidosis Expert Consensus Decision Pathway + 2022 AHA/ACC/HFSA HF Guideline; Gillmore non-biopsy diagnostic algorithm