Cardiac amyloidosis

Abstract

Amyloidosis is a condition characterized by the extracellular deposition of insoluble fibrillar protein in tissues and various organs including the heart. This review summarizes the clinical manifestations, diagnostic and treatment approaches for cardiac amyloidosis.

Keywords::

• AL amyloid
• ATTR amyloid
• cardiac amyloidosis
• treatment

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or a financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Approximately 30 different precursor proteins have the propensity to form amyloid fibrils.

• Mutations in several genes have been associated with hereditary amyloidosis. Most cases are due to the production of amyloid from a mutant transthyretin (TTR) protein.

• AL and TTR are the two types of amyloid commonly infiltrating the heart.

• AL amyloidosis is the most common variety and constitutes about 70% of all patients with amyloidosis.

• Isolated cardiac amyloidosis is rare. Only less than 5% of patients with AL amyloidosis involving the heart have evidence of isolated heart disease.

• Cardiac involvement leads to restrictive cardiomyopathy.

• Serum N-Terminal pro-brain natriuretic peptide and troponins are sensitive marker of cardiac involvement and predictor of prognosis in AL amyloidosis.

• In patients with primary amyloidosis, the presence of cardiac involvement is associated with a worse outcome and the majority of deaths are cardiac related.

• High-dose melphalan and autologous hematopoietic stem cell transplantation is associated with good response rate and improved survival in selected patients with AL, who are eligible for this therapy.

• In future, antibodies or novel agents that block the deposition of serum amyloid fibrils or dissolve amyloid fibrils will play a pivotal role in the management of this disease.