For example, you probably want to know what causes the heart condition and what symptoms and potential complications to expect. You’re also likely interested in available treatment options and overall prognosis. Unfortunately, ATTR-CM is a complex condition that is often diagnosed late, if at all, because some physicians don’t even fully recognize the signs, according to American Heart Association (AHA). That’s why it’s best to consult with a cardiologist with expertise in the condition, says Frederick L. Ruberg, MD, associate chief for academic affairs and director of the advanced cardiac imaging program, section of cardiovascular medicine at Boston Medical Center. Briefly, transthyretin (TTR, also known as prealbumin) is a “transporter” protein manufactured by the liver. TTR carries hormones in the blood that are involved in thyroid function as well as vitamin A. Sometimes these TTR proteins can break apart, misfold, and accumulate in your heart as amyloid fibrils. This can cause the heart to become weak or have difficulty functioning. “Not all physicians have a full understanding of what transthyretin amyloid cardiomyopathy is,” says Dr. Ruberg. However, he adds, understanding your ATTR-CM can help you, and your doctor, better manage your symptoms. Here are some questions to ask your care team:
1. What type of transthyretin amyloid cardiomyopathy do I have?
There are two types of ATTR-CM: hereditary and wild-type. Hereditary ATTR-CM runs in families and is caused by an inherited mutation in the TTR gene, which causes your liver to produce abnormal transthyretin protein that can accumulate in your heart or your nerves. If you have hereditary ATTR-CM, you may start experiencing symptoms as early as your 20s or as late as age 80, according to the AHA. In wild-type ATTR-CM, the gene encoding for the TTR protein is normal, so it’s unclear why the protein breaks apart and misfolds. However, the problem usually begins to surface with aging. People with wild-type ATTR-CM typically don’t experience symptoms until they’re older (usually 65 years and up).
2. What are my treatment options?
Previously, the only treatment for ATTR-CM was organ transplantation, either heart, liver, or both. Now, both hereditary and wild-type ATTR-CM are most commonly treated with medications designed to slow or stop the buildup of amyloid fibrils. Medications called ATTR silencers are designed to control transthyretin production or prevent abnormal transthyretins from accumulating in your heart. Newer drugs, known as ATTR stabilizers, work by binding to and stabilizing the unstable TTR protein, resulting in less amyloid deposition. Finally, fibril disruptors can break up existing transthyretin buildups and induce the body to reabsorb the amyloid proteins, although these drugs are still being researched. All of these strategies can help slow or even reverse the damage caused by amyloid deposition.
3. What can I expect from this treatment?
While none of these options promise a cure, they may prevent progression of disease and in some cases improve your symptoms, says Noel R. Dasgupta, MD, a cardiologist at Indiana School of Medicine and member of the Indiana University Amyloidosis Center.
4. Will I need to have a heart or liver transplant?
If ATTR-CM has progressed to advanced heart failure, heart transplantation may be an option. However, this is usually only an option in people with hereditary ATTR-CM, who tend to be younger, as the wild-type form of the condition tends to strike older adults in whom a heart transplant is not feasible, Ruberg says. In the past, according to Dr. Dasgupta, some people have undergone heart and liver transplantation simultaneously to address ATTR-CM, although this is increasingly rare. Liver transplantation was done in hereditary amyloidosis to stop production of the abnormal transthyretin by the liver.
5. What steps can I take to manage my symptoms?
The best way to manage symptoms is to stick to your doctor-prescribed treatment, Ruberg says. “For patients with ATTR-CM who have congestive heart failure the main treatment focuses on control of heart failure, which typically requires medications designed to manage fluid overload in the heart and control heart arrhythmias,” adds Dasgupta.
6. Why am I feeling short of breath, and is there anything I can do to help with that?
ATTR-CM can cause your heart to become stiff and weak, making it difficult for it to pump blood throughout your body. Blood builds up in your lungs, which can lead to shortness of breath, among other symptoms. Treatment of heart failure and fluid accumulation in the heart can reduce shortness of breath. Diuretics are medications that may help decrease fluid in the lungs and improve breathing. Treatment of abnormal heart rhythms and blockages in the heart arteries can also improve shortness of breath in some patients.
7. When should I seek emergency care?
“Passing out, or syncope, could be a sign of a serious heart arrhythmia,” Dasgupta says. “If you have severe shortness of breath, chest pain, or palpitations, these could be signs of a serious medical problem that requires emergency care.”
8. Can any diet or other lifestyle changes improve my condition?
Although diet and lifestyle changes won’t cure your ATTR-CM, Ruberg emphasizes, they can help you manage the symptoms and reduce your risk for progressing to advanced congestive heart failure. If you haven’t already, the AHA recommends that you quit smoking and eat a diet of nutrient-rich foods, including vegetables, fruits, whole grains, low-fat dairy, poultry, fish, legumes, nontropical vegetable oils, and nuts. You should also limit your intake of sweets, sugar-sweetened beverages, and red meat, and work with your doctor to maintain a healthy weight. In addition, according to the Amyloidosis Foundation, small studies have shown that green tea may help slow the progression of transthyretin-related diseases that involve the heart. Similarly, curcumin, a component of the spice turmeric, has shown some promise in decreasing transthyretin accumulation. Always consult with your doctor before considering any dietary changes or supplements. Although it’s likely that your ATTR-CM symptoms may limit your ability to exercise, you should try to remain physically active. Even walking can help, Ruberg notes.
9. Who should be on my ATTR-CM care team?
The Cleveland Clinic recommends that your care team for ATTR-CM include a cardiologist as well as a genetic counselor to consult with you and your family about hereditary risks for certain conditions. “I think it’s helpful to visit with a cardiologist at a center that specializes in ATTR-CM,” Ruberg says. “They will have the best understanding of the condition and can get you into a clinical trial for the newest treatments, if you’re eligible.”
10. What types of tests will I need and how often will I need them?
Your cardiologist should perform baseline electrocardiograms (ECGs) and echocardiograms to monitor your heart function. He or she may then perform periodic ECGs or cardiac MRIs, if needed, to monitor your heart’s electrical system and heart structure and function. A nuclear medicine scan may also be needed to see if your treatment is controlling or reducing the amyloid buildup in your heart. The frequency of testing depends on your clinical symptoms but is typically at least once per year for ECGs. In general, follow up testing may occur every six to 12 months.
11. What are the potential complications of transthyretin amyloid cardiomyopathy? Are there any signs or symptoms I should be aware of that signal an emergency?
According to Ruberg, complications associated with ATTR-CM include, most notably, progression to congestive heart failure and the development of related conditions such as cardiomyopathy, heart rhythm problems, peripheral neuropathy, and constipation or diarrhea. People with ATTR-CM are not at increased risk for a heart attack, he notes, but they are at risk for serious heart rhythm problems that would need immediate attention. Many of the symptoms of congestive heart failure mirror those of ATTR-CM, so if you experience any of them while on treatment, call your doctor.
12. Should I be monitored for atrial fibrillation?
Atrial fibrillation, or afib, is a common complication among people with ATTR-CM, according to Ruberg. If you have a history of afib, talk to your doctor about the best ways to monitor your heart function. Most patients with afib and ATTR-CM will need blood thinning medication to reduce the risk of stroke.
13. Should I be undergoing treatment for congestive heart failure?
Unfortunately, many of the drugs used to treat congestive heart failure, such as ACE inhibitors and beta blockers, aren’t well tolerated by people with ATTR-CM, causing side effects and complications, Ruberg explains. If you’re being treated for congestive heart failure and have been diagnosed with ATTR-CM, talk to your doctor about the medications you take and see if you need to make any changes.
14. Does having ATTR-CM mean I may get amyloid light-chain amyloidosis?
Amyloid light-chain (AL) amyloidosis is a bone marrow disorder that, like ATTR-CM, is caused by misfolded proteins. Although the two conditions are similar in that both are caused by misfolded proteins, the proteins that misfold are very different and having one doesn’t put you at higher risk to get the other, Ruberg notes. However, he adds, if you have AL amyloidosis and it moves to your heart, it can carry a far worse prognosis than standard ATTR-CM. “I definitely urge my patients to educate themselves about all forms of amyloidosis,” he says. “While I also caution them that there’s a lot we still don’t know about these conditions, they should stay as up to date and on top of their health as possible.”
