Can restrictive cardiomyopathy be reversed? How serious is restrictive cardiomyopathy? What is end-stage restrictive cardiomyopathy? Let’s find out about restrictive cardiomyopathy symptoms and treatment!
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Restrictive Cardiomyopathy Definition
Restrictive cardiomyopathy meaning – What is restrictive cardiomyopathy? Restrictive cardiomyopathy is a condition in which the heart’s chambers stiffen up over time.
Restrictive Cardiomyopathy Causes
What causes restrictive cardiomyopathy? What is the most common cause of restrictive cardiomyopathy? Restrictive cardiomyopathy is caused by a disease called amyloidosis and scarring of the heart that has no known cause. It can also occur after a heart transplant.
In restrictive cardiomyopathy, the diastolic filling isn’t as good, but the size of the LV chamber is mostly the same. As a result, the condition isn’t very common, and amyloidosis is the most common cause.
In the last few years, cardiac amyloidosis has been diagnosed more often because diagnostic tests have improved, and people are more aware of how common it is. AL amyloid is found in about 12 out of every million people, and variant or inherited ATTR amyloid is found in about 0.3 out of every million people. Wild-type ATTR amyloid is found in 155 and 191 out of every million people. Many experts think that the number of wild-type ATTRs is much higher than they think. Even though light chain amyloid proteins can harm cardiomyocytes, they may also get inside many different types of cells. This may explain some of the cardiac dysfunction that has been seen.
ATTR stands for transthyretin, a protein usually found in the liver that helps move vitamin A and thyroid hormones. Wild-type (normal) amyloidosis is more common in older people and men. It was once called “senile systemic amyloidosis.” Hereditary or variant ATTR is passed down through genes, deposits happen at a younger age, and it affects the nervous system.
TTR is a tetramer that can break apart into four single molecules and stick together to form amyloid fibrils. Other than amyloidosis, infiltrative diseases like sarcoidosis, Gaucher disease, and Hurler syndrome are also possible causes of restrictive cardiomyopathy. The picture can also be caused by storage diseases like hemochromatosis, Fabry disease, and glycogen storage disease.
Rarely, non infiltrative diseases like familial cardiomyopathy and pseudoxanthoma elasticum can be a cause. Other secondary causes include diabetes, systemic sclerosis (scleroderma), radiation, chemotherapy, coronary artery disease (CAD), and long-term high blood pressure.
Restrictive Cardiomyopathy Diagnosis
- Most of the time, right heart failure is worse than left heart failure.
- There is high blood pressure in the lungs.
- Most of the time, it is caused by amyloidosis.
- Echocardiography is the key to making a diagnosis.
- Amyloid can be proven with radionuclide imaging or a biopsy of the myocardium.
Restrictive Cardiomyopathy Symptoms
Signs and symptoms of restrictive cardiomyopathy – What are some symptoms of restrictive cardiomyopathy?
Constrictive pericarditis is not the same as restrictive cardiomyopathy. In constrictive pericarditis, the ventricle interaction is stronger when you breathe. At the same time, in restrictive cardiomyopathy, there is no interaction between the ventricles.
Also, the high PCWP means that the pulmonary arterial pressure is always high in restrictive cardiomyopathy. Still, it is normal in simple constrictive pericarditis. Symptoms can include chest pain, fainting, a stroke, and nerve damage in the arms and legs. Physical signs of amyloidosis include periorbital purpura, a thickened tongue, and a swollen liver.
Restrictive Cardiomyopathy Diagnostic Criteria
There are often problems with conduction. For example, when the ECG shows low voltage and the echocardiogram shows that the ventricles are getting bigger, this is a sign of disease. Technetium pyrophosphate imaging also called “bone scan imaging,” can also find amyloid deposition in the myocardium. It is now the imaging method of choice for diagnosing transthyretin amyloidosis because it doesn’t hurt the patient.
When a patient doesn’t have a monoclonal gammopathy and has typical scintigraphic results, a biopsy is no longer needed to diagnose. However, cardiac MRI is a useful screening test because it shows a clear pattern of diffuse hyperenhancement of the gadolinium image in amyloidosis. A lot of late gadolinium hyperenhancement suggests that the heart is more involved. The echocardiogram shows a small, thickened LV with bright (speckled) myocardium. The mitral inflow Doppler shows fast early diastolic filling, and the biatrial size has grown.
Patterns of longitudinal strain typical for cardiac amyloidosis may help diagnose it. When the LVEF is low, the size of the LV chamber is usually normal. There may be thickening of the atrial septum, and a type of amyloid that mostly affects the atria has been described. Biopsies of the rectal tissue, abdominal fat, or gums can confirm systemic involvement. However, myocardial involvement may still be present if these tests return negative. An endomyocardial biopsy is needed to confirm that cardiac amyloid is present.
To figure out which protein is involved, tissue infiltration must be shown on biopsy samples using special stains, followed by immunohistochemical studies and genetic testing. When the TTR wild type or TTR mutant variant is suspected in a patient, it is best to do TTR gene sequencing and mass spectroscopy on all of the tissue in question. BNP and NT-proBNP are often high, which has helped doctors tell the difference between constrictive pericarditis and restrictive cardiomyopathy.
Restrictive Cardiomyopathy Treatment and Management Guidelines
Treatment of restrictive cardiomyopathy – What is the best treatment for restrictive cardiomyopathy?
AL amyloidosis is treated with alkylator-based chemotherapy or high-dose melphalan, followed by an autologous stem cell transplant. Immunoglobin light chain amyloidosis is usually treated with standard or high doses of chemotherapy and stem cell rescue.
ATTR amyloid treatment is changing. Tafamidis prevents the TTR tetramer from folding incorrectly and is now approved as a treatment. Patisiran is also available and blocks both wild-type and variant TTR production. For TTR polyneuropathy, subcutaneous inotersen is available (it binds to TTR mRNA, preventing transcription).
When someone has sudden heart failure, diuretics can help, but if they use them too much, it can worsen their kidney function. Most people with severe right heart failure benefit from loop diuretics, thiazides, and aldosterone antagonists. Atrial thrombi are fairly common, but the role of anticoagulation in amyloidosis is still unclear. Digoxin can cause irregular heartbeats and shouldn’t be used. By lengthening the time the heart spends in the diastolic phase, beta-blockers help slow the heart rate and improve filling by making the heart beat slower during the dia Verapamil probably works by helping the myocardium relax and by making the diastolic filling time longer.
We want slow heart rates so the diastolic filling time can be lengthened. Angiotensin II receptor blockade or angiotensin-converting enzyme (ACE) inhibition may help diastolic relaxation and filling if the systemic blood pressure is normal. Corticosteroids may help with sarcoidosis, but they work better for sarcoidosis-related conduction problems than for heart failure.
When a patient has restrictive cardiomyopathy, he or she should be sent to a cardiologist so that the cause can be determined and the right treatment can be planned. Unknown LVH with relatively normal LVEF and heart failure symptoms should make you think about cardiac amyloid, especially now that there are effective treatments.
I hope you understand restrictive cardiomyopathy symptoms and treatment guidelines.