Transthyretin amyloid cardiomyopathy (ATTR-CM) is a rare but serious disease caused by the buildup of abnormal deposits of a protein called transthyretin in the heart. These protein deposits interfere with the normal workings of the heart and can lead to heart failure if not treated properly. In this article, we will discuss the causes, symptoms, diagnosis and various treatment options available for ATTR-CM.

Causes of ATTR-CM

ATTR-CM can be caused due to two main reasons - wild type or mutant transthyretin. Wild type ATTR-CM is usually seen in elderly men and is caused due to a natural age-related buildup of wild type transthyretin protein in the heart. Mutant ATTR-CM is caused due to a inherited genetic mutation in the transthyretin gene. This mutation causes the transthyretin protein to fold abnormally and deposit in various organs including the heart. Over 100 mutations have been identified so far that can cause ATTR-CM. The Val30Met mutation is the most commonly seen mutation worldwide.

Symptoms of ATTR-CM

The Transthyretin Amyloid Cardiomyopathy Treatment symptoms of ATTR-CM can vary between individuals but some common symptoms include fatigue, shortness of breath, leg swelling and problems related to irregular heartbeats. As the disease progresses, people may develop symptoms of right or left sided heart failure such as increased shortness of breath, swelling of legs/abdomen due to fluid retention, loss of appetite and persistent cough. Some may also report symptoms of low blood pressure or lightheadedness due to poor pumping of the heart. Without treatment, ATTR-CM can cause loss of mobility, worsening heart failure and even death within 3-5 years of diagnosis.

Diagnosis of ATTR-CM

No single test can confirm ATTR-CM. Doctors rely on a combination of tests to make the diagnosis. Initial tests may include echocardiogram, cardiac MRI or nuclear imaging to check characteristics of cardiac amyloidosis. Blood tests to rule out other diseases and biopsy of fatty tissue or organs are also done to confirm amyloid deposits and their type (ATTR vs others). Genetic testing helps identify mutations in patients suspected with hereditary ATTR-CM. A positive scan with radioactive tracers like 123I-SAP and 99mTc-pyrophosphate that bind to amyloid deposits provides additional support for diagnosis.

Treatment Options for ATTR-CM

Once diagnosed, treatment aims to reduce symptoms, improve quality of life and slow the progression of heart disease. The main treatment options include:

Medication: Medications for managing heart failure symptoms like diuretics, beta-blockers, ACE inhibitors are commonly prescribed. Medications to reduce aggregation and deposition of abnormal transthyretin like tafamidis and diflunisal are also being used.

Liver Transplant: As the liver produces most of the mutant transthyretin, liver transplant was an option tried earlier to stop further production. However, it provided minimal benefits and was associated with risks. It is no longer routinely recommended.

Get more insights on Transthyretin Amyloid Cardiomyopathy Treatment