Heart failure can be a complex condition with many underlying causes, one of which is cardiac amyloidosis (CA). CA is a rare but increasingly recognised cause of heart failure. To support healthcare professionals in Scotland with early diagnosis and management of suspected cardiac amyloidosis, a new Cardiac Amyloidosis Diagnostic Pathway has been developed. This pathway provides clear guidance on when to suspect CA, diagnostic tests required, and referral options, ensuring patients receive timely and appropriate care.
Why is this important?
Cardiac amyloidosis, caused by abnormal protein deposits in the heart, can significantly impact cardiac function, quality of life and outcomes for patients. The two main types affecting the heart are:
- Transthyretin amyloidosis (ATTR) – further divided into wild-type ATTR and hereditary ATTR (associated with genetic variants, including those found in the Scottish population).
- Light chain (AL) amyloidosis – caused by abnormal plasma cell production, requiring urgent haematological assessment.
Despite its severity, CA is often underdiagnosed. The new diagnostic pathway streamlines the process, helping healthcare professionals recognise red flags, initiate the correct investigations, and facilitate timely referrals for specialist care.
Key Features of the Pathway
Recognising red flags
Healthcare professionals should consider cardiac amyloidosis in patients over 60 years old presenting with heart failure and left ventricular wall thickening (>12mm), particularly if they have no history of hypertension. Other key clinical features include carpal tunnel syndrome, neuropathy and orthostatic hypotension.
Essential Diagnostic Steps
The pathway outlines a stepwise approach to diagnosis:
- Haematological testing: to screen for AL amyloidosis using serum protein electrophoresis & immunofixation, urinary Bence Jones and serum free light chains.
- Cardiac imaging: including echocardiography and cardiac MRI (with T1 and extracellular volume mapping) to assess for characteristic features of amyloid deposits.
- DPD scintigraphy: a non-invasive bone scan available in multiple Scottish health boards.
- Genetic testing: recommended if ATTR is diagnosed to differentiate between wild-type and hereditary forms.
Specialist referral & multidisciplinary support
If cardiac amyloidosis is confirmed or strongly suspected, referral to the National Amyloidosis Centre (NAC) in London is advised. However, for patients unable to travel, local guidance is available to facilitate specialist input through haematology, cardiology, and genetic services in Scotland.
What this means for heart failure patients in Scotland
By increasing awareness and providing a structured diagnostic approach, this pathway aims to improve early detection and treatment of cardiac amyloidosis. This will help ensure that patients receive the most appropriate therapy, whether supportive heart failure treatment, chemotherapy (for AL amyloidosis), or disease-modifying therapies (for ATTR).
ATTR-CM is an underdiagnosed condition that can often be overlooked as a cause of heart failure. Over one-third of patients have symptoms for over three years prior to a diagnosis and misdiagnosis occurs in up to one-half of patients. In the three years leading up to diagnosis, patients attend secondary care a median of 17 times. Amyloidosis is challenging to suspect, recognise, and diagnose. The guidelines are designed to be accessible and easy to use in order to support early identification and testing. The key diagnostic components are accessible across Scotland. The goal is to lead to earlier treatment and improve patient outcomes. By maintaining a high level of suspicion, we can identify patients earlier in their journey, eliminate delays, and improve equity of access to care.
Next steps
The Cardiac Amyloidosis Diagnostic Pathway is now available for use across Scotland. We encourage all cardiology, haematology, and primary care professionals to familiarise themselves with the pathway and consider cardiac amyloidosis in patients with unexplained heart failure.
For further information and access to the full pathway, please visit the Heart Failure Hub Scotland website.
Together, we can enhance early recognition, improve patient outcomes, and raise awareness of this often-overlooked condition.