A disorder known as transthyretin amyloidosis (ATTR) causes the buildup of the protein amyloid in several organs, including the heart, neurons, and others. Transthyretin amyloid cardiomyopathy is a potentially fatal cardiac condition that it may cause (ATTR-CM).
The particular form of amyloid protein that accumulates in the heart of ATTR-CM patients is transthyretin. Typically, it is responsible for transporting thyroid hormone and vitamin A throughout the body.
Wild type and inherited transthyretin amyloidosis are the two main forms of this condition.
There is no hereditary basis for wild-type ATTR, also called senile amyloidosis. The protein that was deposited is in its original, unaltered state.
The protein is produced improperly in cases of inherited ATTR (misfolded). Then, it forms clumps, increasing the likelihood that it may enter your body’s tissues.
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What Are The Symptoms Of ATTR-CM?
The left ventricle of your heart pumps your circulatory system. The walls of this heart chamber are susceptible to ATTR-CM.
The walls become rigid due to the amyloid deposits, making them unable to relax or contract naturally.
Because of this, your heart cannot pump blood efficiently or fill the chambers of your body with blood (decreased diastolic function) (reduced systolic function). A kind of heart failure is known as restricted cardiomyopathy.
Dyspnea, or difficulty breathing, particularly when laying down or exerting oneself, leg swelling, and an irregular heartbeat are all signs of this kind of heart failure (peripheral edema)
- chest discomfort
- irregular pulse (arrhythmia) (arrhythmia)
- palpitations
- lethargy, enlarged spleen and liver (hepatosplenomegaly)
- abdominal fluid (ascites)
- lack of hunger
- weakness, particularly while standing (syncope)
Elevated blood pressure that gradually improves is an unusual symptom that might arise. Because your heart isn’t able to pump blood efficiently enough to maintain high blood pressure, this occurs.
- Amyloid deposits in organs other than the heart may cause other symptoms such as:
- palmar tendinitis
- discomfort, paresthesia, or burning in the limbs (peripheral neuropathy)
- spinal stenosis causes back discomfort
When To See The Doctor
Quickly dial 911 if you’re experiencing chest discomfort. Immediately see a doctor if you have any of the following symptoms:
- increasing shortness of breath
- severe leg swelling or rapid weight gain
- rapid or irregular heart rate
- pauses or slow heart rate
- dizziness
- fainting
What Causes ATTR-CM?
Two distinct forms of ATTR arise from different sources.
Hereditary (Familial) ATTR
A genetic mutation causes transthyretin to misfold in this form. It may be inherited from parent to kid via the genes. Even while symptoms could start in your twenties, they most often manifest in your fifties.
Wild-Type ATTR
Proteins often undergo misfolding. These proteins won’t create any problems for your body since it has systems to eliminate them. Misfolded proteins may aggregate and create deposits due to these processes becoming less effective with age. In ATTR of the wild type, it is the result.
Due to the lack of a genetic mutation, wild-type ATTR cannot be transmitted from one generation to another. Typically, symptoms manifest in the latter years of life.
How Is ATTR-CM Diagnosed?
The symptoms are similar to those of other forms of heart failure, making diagnosis challenging.
- An ECG may reveal if the heart walls are thick due to deposits, which is a popular diagnostic test (usually the electrical voltage is lower)
- Cardiac echocardiography to detect thick walls, evaluate cardiac function, detect aberrant relaxation patterns, and detect indicators of elevated cardiac blood pressure
- Imaging techniques such as magnetic resonance imaging (MRI) and cardiac biopsies may detect amyloid deposits in the heart’s lining and muscle research aiming to identify inherited ATTR
How Is ATTR-CM Treated?
The liver is the primary site of transthyretin production. This is why, in some cases, a liver transplant is the treatment of choice for hereditary ATTR-CM. A heart transplant is often performed concurrently with the diagnosis of the illness due to the irreversible damage to the heart.
The FDA authorized two medicine formulations for ATTR CM in 2019: tafamidis meglumine (Vyndaqel) and tafamidis (Vyndamax) pills. Diuretics may alleviate some of the symptoms of cardiomyopathy by removing extra fluid.
Digoxin (Lanoxin) and beta-blockers are two other common heart failure drugs that should not be regularly taken because of the potential damage they might cause in this situation.
What Are The Risk Factors?
Risk factors for hereditary ATTR-CM include:
- a family history of the condition
- male gender
- age over 50
- African descent
Risk factors for wild-type ATTR-CM include:
- age over 65
- male gender
What Is The Outlook If You Have ATTR-CM?
Progression of ATTR-CM is inevitable in the absence of a liver and heart transplant. Persons diagnosed with ATTR-CM typically have a life expectancy of 2.5 to four years.
The illness might worsen your quality of life. However, medicine can assist a lot with the symptoms.