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Four key indicators of ATTR-Cardiac Amyloidosis (ATTR-CM) that showed a patient what was wrong with his heart
How this treatment helped him manage his heart condition
By WP Creative Group
November 3, 2025
Please see Important Safety Information for Attruby® (acoramidis) below. For the Full Prescribing Information and Patient Information for Attruby, visit Attruby.com/PI.
Ken couldn’t seem to catch his breath. He’d never fully bounced back from his second rotator cuff surgery. He could no longer swim as fast or as far as he had before. A year after the surgery, he was back in the hospital — this time, because he’d suffered a stroke.
“I blamed myself for the slow recovery, for not pushing hard enough,” Ken said. “In hindsight, there was probably another reason.”
Ken’s search for answers brought him to nearly a dozen doctors. After months of tests, he was finally diagnosed with a rare condition called ATTR-cardiac amyloidosis, or ATTR-CM. A second opinion confirmed there was no cure, and Ken prepared for what seemed like would be several years of slow decline.
“I started thinking about the need to review our wills,” he said.
An active older man who cherishes daily activity like exercise and walking his dogs, Ken continued looking for ways to improve his condition. Soon he had reason for hope: he participated in a clinical trial and was put on an investigational product, later approved as Attruby. While ATTR-CM is not curable, Attruby was being studied to evaluate whether it could slow the progression of the condition. (See Important Safety Information below. For full prescribing information for Attruby, visit Attruby.com/PI.)
ATTR-CM is a progressive condition that interferes with the normal functioning of the heart. There are two main types of ATTR-CM, one that is inherited through one’s family, and one that is caused by natural aging. Ken’s condition was not hereditary. In both cases, it all starts with transthyretin (TTR), an important protein which transports vitamin A and metabolism-supporting hormones as it circulates through the bloodstream. If TTR becomes unstable, it can break down into smaller proteins that clump together into what is known as amyloid fibrils, which then deposit in tissues, including the heart, says Dr. Richard Wright, a cardiologist at Cedars-Sinai Pacific Heart Institute.
Attruby works by stabilizing TTR so that TTR is less likely to break down. In laboratory tests, over 90 percent of TTR proteins were stabilized with Attruby, which was seen as early as 28 days. In a clinical study, people treated with Attruby did significantly better than those not taking Attruby, based on a combined measure of survival and hospitalizations due to heart issues. Impact was seen as early as three months. By the end of the study at 30 months, people had reduced hospital visits by 50 percent. (With the placebo, study members reported 0.6 hospital visits per year, while with Attruby that dropped to 0.3.) The most common side effects of Attruby were mild and included diarrhea and stomach-area (abdominal) pain.
It’s unclear how many people have ATTR-CM, largely because it’s often underdiagnosed or misdiagnosed altogether. Many of the signs and symptoms overlap with other common heart conditions, meaning it can sometimes take years to reach a formal diagnosis. Medical experts say it’s critical for patients and physicians alike to recognize early indicators and know that treatment is available.
“Early recognition is important,” Wright said. “If not treated, ATTR-CM inexorably gets worse. It just progresses over time and shortens people’s lives.”
– Dr. Richard Wright, Cedars-Sinai Pacific Heart Institute
Here are four key symptoms to look for:
Shortness of breath
For Ken, shortness of breath stood out as a key symptom that impaired his regular routine.
When the heart malfunctions, it can be difficult to breathe. The kind of breathlessness normally associated with heavy exercise is present constantly, as Dr. Wright put it, “because of this combination of the heart and the lungs not doing their job.” Soon, shortness of breath wasn’t just affecting Ken’s swimming. As his condition progressed, even getting around his home was difficult at times.
“I struggled to climb even a single set of stairs without pausing halfway up to catch my breath—and our bedroom is on the second floor,”
— Ken, Attruby patient
Tiredness or weakness
Another symptom occurs when the body becomes tired and weak because there’s not enough blood and oxygen being circulated. “People sometimes overlook these symptoms or write them off as typical signs of aging,” Wright said, “but they shouldn’t assume they’re just out of shape.”
Swelling in legs or feet
One of the most challenging symptoms of Ken’s ATTR-CM was fluid retention, caused because his heart was not pumping fluid around his body as it should. Ken built up so much fluid that he was hospitalized for treatment, which resulted in him losing 45 pounds of fluids in just five days.
“Many normal conditions or activities can lead to swollen ankles and feet,” Wright said, “like sitting on a plane for hours during an international flight. But when the heart is malfunctioning, it sends signals to the kidneys to make less urine. If each day, the kidneys hang on to a little bit of fluid, where does that fluid go?” The answer is usually a person’s lower extremities, causing swelling that can be a warning sign of larger issues.
Irregular heartbeat
“If the heart becomes so laden with amyloid fibrils, it becomes stiff and more rigid,” Wright said, causing the walls of the heart to thicken, almost like pouring concrete onto the muscle. Over time, this buildup of protein deposits can interfere with the heart’s normal functions, including its rhythm and electrical wiring.
In practice, Wright says patients with ATTR-CM may notice an irregular heartbeat where their heart feels like it is fluttering or skipping a beat.
Early indicators of progression
Ken’s two rotator cuff surgeries may have ended up having more to do with his heart condition than he ever imagined. The same protein deposits in his heart were likely building up in his shoulders, too.
Roughly 60 percent of patients diagnosed with ATTR-CM also experience numbness and tingling in the hands, due to carpal tunnel syndrome. Up to 40 percent of people with ATTR-CM also experienced spinal stenosis, where the space within the backbone narrows and applies pressure on the spinal cord. These can be early warning signs of abnormal protein buildup in the body.
Ken says that beginning to treat his ATTR-CM with Attruby was a turning point in his life. He’s still being monitored as part of the clinical trial and he continues to take Attruby to help stabilize his TTR proteins and help prevent abnormal deposits from building up in his heart. The shortness of breath that plagued him has receded. On a recent vacation, a fire alarm forced him and his wife to evacuate the hotel. Once, walking down those stairs would have been impossible. But on this trip, Ken didn’t just walk down the stairs: When the emergency was over, he and his wife walked back up.
“I couldn’t have done this before I started treatment with Attruby,” he said.
If you have a heart condition or are experiencing symptoms similar to those described by Ken, consult your healthcare provider for medical advice.
IMPORTANT SAFETY INFORMATION AND USE
Before taking Attruby, tell your healthcare provider about all your medical conditions, including if you:
- are pregnant or plan to become pregnant
- are breastfeeding or plan to breastfeed
Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
What are the possible side effects of Attruby?
The most common side effects of Attruby were mild and include:
- diarrhea
- stomach-area (abdominal) pain
These are not all of the possible side effects of Attruby. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-332-1088 or www.fda.gov/medwatch.
What is Attruby?
Attruby is a prescription medicine used to treat adults with a disease that affects the heart muscle called cardiomyopathy of wild-type or variant transthyretin-mediated amyloidosis (ATTR-CM), to reduce death and hospitalization related to heart problems.
It is not known if Attruby is safe and effective in children.
For the Full Prescribing Information and Patient Information for Attruby, visit Attruby.com/PI.
Attruby® and the Attruby logo are trademarks of BridgeBio Pharma, Inc.
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