Restrictive cardiomyopathy (RCM) is the least common cardiomyopathy, defined by restrictive ventricular physiology — marked diastolic dysfunction with non-dilated ventricles and biatrial enlargement. It is heterogeneous in cause, which shapes its management.
Diagnosis and management
Because patients depend on high filling pressures to maintain cardiac output, volume management is delicate: excessive diuresis can compromise perfusion. Given the heterogeneity, treatment is individualized, and cardiac transplantation remains the preferred option for long-term survival in progressive disease with poor prognosis. Antithrombotic therapy is recommended at diagnosis, particularly in pediatric RCM, where thrombosis risk is high.
Cause-specific therapy and emerging directions
An important development lies in the infiltrative causes of restrictive physiology: transthyretin amyloid cardiomyopathy, a major cause of RCM in older adults, now has disease-specific therapy — the TTR stabilizers tafamidis and, more recently, acoramidis, alongside TTR-lowering agents — which has transformed a once-untreatable cause of restriction. More broadly, genomic characterization of the cellular mechanisms of myocardial restriction is identifying potential new targets, and novel left ventricular assist device cannulation techniques (such as transseptal left atrium-to-aorta cannulation) are being explored to address the specific challenges these patients pose for mechanical support.
Further reading: restrictive cardiomyopathy definition and diagnosis (Rapezzi et al., European Heart Journal 2022); AHA scientific statement on treatment of cardiomyopathy in children (Bogle et al., Circulation 2023); transthyretin amyloid cardiomyopathy therapy (tafamidis, acoramidis).