Article Summary

1. Cardiac amyloidosis can be difficult to diagnose, especially for those patients with transthyretin amyloidosis.
2. Heart failure and accompanying symptoms like arrhythmias can be a red flag with cardiac amyloidosis.
3. To detect cardiac amyloidosis, providers must obtain serum studies and perform imaging tests to diagnose the condition and determine its subtype.

Over the past two decades there has been a significant increase in both the incidence and prevalence of cardiac amyloidosis. This is most likely due to improved screening and diagnosis. However, even with these advances, delayed diagnosis is common.

Diagnosis typically takes two years for patients with amyloid light-chain amyloidosis (AL), and up to 7.2 years for those with transthyretin amyloidosis (ATTR), explains Temple heart failure cardiologist Carly Fabrizio, DO.

“We now know that light chain is rare, but transthyretin is not so rare as we previously used to think,” she says. “You really need to have a low threshold to screen for patients.”

Providers should move quickly to accurately diagnose cardiac amyloidosis and determine its underlying cause, she says. Early treatment is key, since current therapies are most effective at preventing further damage. 

Red Flags for Cardiac Amyloidosis

Heart failure, regardless of ejection fraction, combined with certain other symptoms should be considered a red flag for amyloidosis, she says. These can include:

• Arrhythmias, most commonly atrial fibrillation, but also including bradyarrhythmias
• Unexplained neuropathy
• Echocardiogram with unexplained left ventricular wall thickness
• EKG and echocardiogram findings that don’t match
• Progressive intolerance to anti-hypertension medications

Because amyloidosis can affect other organs, providers should also have non-cardiac symptoms on their radar. Musculoskeletal issues like carpal tunnel syndrome and spinal stenosis can be an early warning sign for ATTR, while kidney problems, autonomic dysfunction, and neuropathy are a red flag for AL.

Early Diagnosis and Treatment is Key

Providers who suspect cardiac amyloidosis should first obtain serum studies, followed by imaging tests to diagnose the condition and determine type and subtype. Testing for light-chain amyloidosis should be the first step, since these patients require chemotherapy, and early diagnosis is known to affect survival.

Treatment for ATTR includes gene silencer medications to help stop the production of transthyretin in the liver. Other medications include protein stabilizers; these drugs show a significant mortality benefit but typically take around 18 months to make a difference.

Fabrizio notes that providers should collaborate with other specialists to manage the effects of amyloidosis on other parts of the body.

“This is a multi-organ issue,” she says. “Remember that a multidisciplinary approach is best.”

Other topics Dr. Fabrizio covers in this presentation include:

• When to biopsy and what to look for
• Whether and when to use beta blockers, ACE inhibitors, MRAs, and SGLT2 drugs
• Current and upcoming research on additional treatments