Some cardiomyopathies do not present with muscular hypertrophy or ventricular dilatation.
Instead, the ventricular filling is restricted, resulting in symptoms and signs of heart failure.
Dilatation of the atria and thrombus formation commonly occur.
Conditions associated: (linked to fibrotic infiltration and therefore restriction of expansion)
- o Amyloidosis
- o Sarcoidosis
- o Loeffler’s endocarditis (eosinophillic infiltrate)
- o Endomyocardial fibrosis (sub-endocardial)
- o Dyspnoea
- o Fatigue
- o Embolic symptoms
- o Restriction to ventricular filing result in persistently elevated central venous pressures (CVP), consequent hepatic enlargement, ascites, and dependent oedema – presenting like RHF.
- o High jugular venous pressure with diastolic collapse = Friedreich’s sign
- o Elevation of venous pressure with inspiration = Kussmaul’s sign
- o S4: heard in restricted/hypertrophic ventricles due to increased force required to fill atria
- Chest xray
- o May show pulmonary venous congestion
- o Cardiac silhouette can be normal or show cardiomegaly and/or atrial enlargement.
- o Low voltage
- o ST segment and T wave abnormalities
- o Symmetrical myocardial thickening
- o Normal systolic ejection fraction
- o Impaired ventricular filling
- Cardiac catheterisation
- o Help distinct it from constrictive pericarditis
No specific treatment
Cardiac failure and embolic manifestations should be treated.
N.B = restrictive CMP and constrictive pericarditis present in similar way – be cautious in differentiation.