AKT · Cardiovascular/Failure & myocardiumlow yield

Restrictive cardiomyopathy & ARVC

Stiff non-compliant ventricle (restrictive) / fibrofatty RV replacement (ARVC)

Overview

Two less common cardiomyopathies. Restrictive cardiomyopathy = stiff, poorly compliant ventricles with impaired filling and preserved EF (amyloid, sarcoid, haemochromatosis, endomyocardial fibrosis) — presents like right heart failure and mimics constrictive pericarditis. Arrhythmogenic right ventricular cardiomyopathy (ARVC) = fibrofatty replacement of the RV causing ventricular arrhythmia and sudden death in young people.

Recognise

Restrictive: predominant right heart failure (raised JVP, ascites, oedema) with relatively preserved EF; fatigue, dyspnoea; signs of the underlying systemic disease (amyloid, sarcoid)
ARVC: palpitations, exertional syncope, ventricular arrhythmia/sudden death in a young adult; epsilon waves and T-wave inversion in V1–V3
Restrictive often mimics constrictive pericarditis — distinguishing them changes management

Red flags

ARVC with syncope/arrhythmia/family history of sudden death → ICD and exercise restriction
Cardiac amyloid (low-voltage ECG with thick walls on echo) → refer for amyloid-specific therapy

Differentials & how to tell them apart

Constrictive pericarditispericardial calcification/thickening, surgically treatable — MRI/catheter studies distinguish from restrictive

Other cardiomyopathiesdilated/hypertrophic morphology on imaging

Right heart failure from lung diseaseprimary respiratory cause

Investigations

Echo (restrictive filling, preserved EF / RV dilatation and dysfunction); cardiac MRI (infiltration, fibrofatty RV); ECG; endomyocardial biopsy/bone scintigraphy for amyloid; genetic testing for ARVC; work-up for sarcoid/haemochromatosis.

Management

Treat the underlying cause; cautious diuresis; ICD for ARVC at risk

1Image with echo/MRI to characterise; distinguish restrictive cardiomyopathy from constrictive pericarditis (the latter is surgically curable). Identify the infiltrative cause.Gate: ARVC with syncope, ventricular arrhythmia or a family history of sudden death → ICD and exercise restriction.
2Treat the cause (amyloid/sarcoid/iron), use cautious diuresis for congestion, and manage arrhythmia; family screening for ARVC.

Treat the underlying infiltrative disease — amyloid-specific therapy, immunosuppression for sarcoid, venesection for haemochromatosis

Cautious diuretics for congestion — these ventricles are pre-load dependent — avoid over-diuresis

ARVC: beta-blocker, antiarrhythmics, ICD — plus exercise restriction (exertion accelerates ARVC)

Key points

Right-heart-failure picture with preserved EF and stiff ventricles = restrictive cardiomyopathy (think amyloid/sarcoid/iron) — and always separate it from surgically curable constrictive pericarditis. Young adult with exertional arrhythmia + V1–V3 changes = ARVC → ICD + stop competitive exercise.

Monitor & prognosis

Disease-specific markers, arrhythmia surveillance, ICD checks, family screening.

Depends on the underlying disease; ARVC carries sudden-death risk.

Source: ESC cardiomyopathy guidance