Transthyretin cardiac amyloidosis (ATTR-CM) isn’t just a heart condition. The same abnormal protein buildup that affects the heart can also harm your nerves, leading to a condition called neuropathy. This nerve damage can cause a wide range of symptoms, from tingling in the toes to more severe issues like dizziness, digestive problems, and even incontinence.
Why this matters: Neuropathy often develops gradually, meaning symptoms can be overlooked or mistaken for something else. Early detection is crucial because the longer nerve damage goes untreated, the harder it becomes to reverse.
How ATTR-CM Causes Nerve Damage
ATTR-CM occurs when misfolded transthyretin proteins accumulate in tissues, including the heart and nerves. This buildup disrupts normal nerve function. There are two main types: hereditary (genetic) and wild-type (no known cause).
The peripheral nerves, responsible for communication between the brain and the rest of the body, are particularly vulnerable. These nerves control everything from muscle movement to digestion. When amyloid deposits form on them, it can affect:
- Sensory nerves: leading to numbness, pain, or tingling.
- Motor nerves: causing weakness or difficulty moving.
- Autonomic nerves: disrupting involuntary functions like breathing, digestion, and blood pressure regulation.
Common Neuropathic Symptoms
Symptoms of ATTR-CM-related neuropathy can be varied and sometimes subtle. They may even appear before heart symptoms, making diagnosis challenging. Common signs include:
- Digestive issues: diarrhea, constipation, or nausea.
- Sexual dysfunction: erectile dysfunction or loss of libido.
- Urinary problems: incontinence or difficulty urinating.
- Eye issues: dry eyes, blurred vision, or glaucoma.
- Dizziness and fainting: caused by low blood pressure when standing (orthostatic hypotension).
- Fatigue and weakness.
- Sweating abnormalities: excessive or reduced sweating.
The challenge: Many of these symptoms overlap with other conditions, which can delay diagnosis. Doctors must consider all possibilities to identify ATTR-CM early. If left untreated, neuropathy can progressively impair daily tasks like walking, dressing, or even gripping objects.
Treatment Options and Future Outlook
Fortunately, treatments are available to slow or stop nerve damage. Medications like gene silencers (vutrisiran, patisiran, eplontersen) reduce the production of the problematic transthyretin proteins. These therapies can improve mobility, reduce pain, and alleviate digestive symptoms.
“Earlier treatment leads to a better quality of life,” says Elizabeth A. Mauricio, MD, a neurologist at Mayo Clinic.
While these medications don’t cure the condition, they can halt progression. Nerve repair is possible, but it’s a slow and often incomplete process.
What to do: If you have ATTR-CM or suspect you may, discuss these symptoms with your healthcare team. Sharing all details can help ensure accurate diagnosis and prompt treatment.
In conclusion, nerve damage is a significant complication of ATTR-CM that requires attention. By recognizing the symptoms and seeking early treatment, patients can improve their quality of life and slow disease progression.
