II. Incidence
- Least common form of Primary Cardiomyopathy (2-5% of cases)
III. Pathophysiology
- Normal systolic function
- Decreased ventricular filling progresses to right-sided Heart Failure
- Restrictive Cardiomyopathy Definition
- Heart Muscle dysfunction secondary to stiff ventricles that interfere with contraction
IV. Causes
- See Cardiomyopathy
- Infiltrative Cardiomyopathy
- Structural and component abnormalities
- Desmin abnormality
- Troponin abnormality
V. Signs
VI. Imaging
-
Chest XRay
- Pulmonary vascular congestion
VII. Diagnostics
-
Electrocardiogram
- Decreased voltage
- Prolonged PR Interval (first degree AV Block)
- Biatrial enlargement
-
Echocardiogram
- Biatrial enlargement
- Diastolic Dysfunction
- Normal or reduced ventricular volume with impaired ventricular filling
- Normal left ventricular wall thickness and normal systolic function
-
Cardiac MRI (CMR)
- May identify underlying cause (infiltrative or storage disease cause)
- Other testing in unclear cases
- Endomyocardial biopsy
- Genetic analysis
VIII. Management
-
General Measures
- See Diastolic Dysfunction
- Salt Restriction
- Diuretics for volume overload
- Resulting Hypotension may limit the use of Beta Blockers, ACE Inhibitors and ARBs in Restrictive Cardiomyopathy
- Specific management based on underlying condition
- Chelation therapy or Phlebotomy for infiltrative processes
- Devices
- Pacemaker (for higher grade AV Block)
- Implantable Defibrillator
- Cardiac Transplantation for children with recently diagnosed Restrictive Cardiomyopathy
IX. Prevention
- Screening for first degree relatives of those with Dilated Cardiomyopathy (e.g. ekg, Echocardiogram, exam)
- Screen every 3-5 years