What is Cardiac Amyloidosis?
Cardiac amyloidosis is a condition where abnormal proteins, called amyloid fibrils, build up in the heart muscle. These deposits cause the heart walls to become stiff and thickened, hindering the heart’s ability to fill with blood properly and potentially leading to heart failure. Once considered a rare disease, cardiac amyloidosis is now being diagnosed more frequently thanks to advances in imaging technology and increased clinical awareness.
Two Main Forms of the Disease
Not all cardiac amyloidosis is the same. The forms most often affecting the heart are:
- Transthyretin amyloidosis (ATTR): This can be linked to aging – often referred to as “wild-type” or “senile” ATTR – or to an inherited genetic mutation.
- AL amyloidosis (from light chains): This form is associated with a blood disorder (plasma cell dyscrasia) and requires prompt, multidisciplinary medical intervention.
Recognizing the Symptoms
The signs of cardiac amyloidosis can be subtle and often mimic other, more common conditions. Common symptoms include:
- Shortness of breath (dyspnea), particularly with exertion.
- Persistent fatigue and weakness.
- Swelling in the legs and ankles (edema).
- Non-cardiac symptoms: Many patients also experience symptoms not directly related to the heart, such as carpal tunnel syndrome (often in both hands), tingling in the hands and feet, or digestive problems.
Diagnosis and Treatment
Diagnosing cardiac amyloidosis requires a comprehensive approach. Advanced diagnostic imaging, including cardiac magnetic resonance imaging (MRI), is crucial for identifying the characteristic patterns of amyloid deposits in the heart. Other tests help determine the specific type of amyloidosis, guiding treatment decisions.
New Therapeutic Options
Historically, cardiac amyloidosis presented a significant therapeutic challenge. However, recent advances have brought new hope to patients. Innovative medications, such as transthyretin stabilizers and gene silencers, are now available and can significantly slow the progression of the disease and improve quality of life. These treatments target the underlying protein buildup, offering a more effective approach than managing symptoms alone.
Understanding the Types of Amyloidosis
The two main types, ATTR and AL amyloidosis, differ in their causes and treatment approaches. ATTR amyloidosis involves the buildup of transthyretin protein, while AL amyloidosis results from abnormal production of light chain proteins. The specific type of amyloidosis dictates the most appropriate treatment strategy.
ATTR amyloidosis is the more common form, particularly in older adults, especially men over 60. AL amyloidosis, is linked to a plasma cell disorder and often requires a more complex treatment plan involving chemotherapy and stem cell transplantation.
The Importance of Early Detection
Early diagnosis is critical for improving outcomes in cardiac amyloidosis. Because the symptoms can be nonspecific, it’s important to consider amyloidosis in patients with unexplained heart failure, particularly those with associated symptoms like carpal tunnel syndrome or neuropathy. Prompt diagnosis allows for timely initiation of appropriate treatment, potentially slowing disease progression and improving survival.
The increasing prevalence of diagnosed cases is attributed to improved diagnostic techniques, allowing for earlier and more accurate identification of the condition. This highlights the importance of continued research and awareness among healthcare professionals.
What to Expect During Diagnosis
A diagnosis of cardiac amyloidosis typically involves a combination of tests, including:
- Electrocardiogram (ECG): To assess the heart’s electrical activity.
- Echocardiogram: An ultrasound of the heart to evaluate its structure and function.
- Cardiac MRI: Provides detailed images of the heart muscle and can help identify amyloid deposits.
- Blood tests: To assess organ function and identify specific proteins associated with amyloidosis.
- Biopsy: In some cases, a biopsy of the heart or other affected tissues may be necessary to confirm the diagnosis.
