Non-Invasive Diagnostic Algorithm in Transthyretin Cardiac Amyloidosis: Is Bone Scintigraphy Always Enough?

Area of Science:

• Cardiology
• Nuclear Medicine
• Radiology

Background:

• Technetium-99m bone scintigraphy has improved transthyretin cardiac amyloidosis (ATTR-CM) diagnosis and recognition.
• Incidental myocardial uptake may be detected in patients without typical red flags, necessitating careful evaluation.

Purpose of the Study:

• To highlight the importance of integrating scintigraphy findings with clinical context.
• To emphasize the complementary role of cardiac magnetic resonance (CMR) imaging in diagnosing ATTR-CM.
• To prevent misdiagnosis and inappropriate therapy in complex cases.

Main Methods:

• Review of clinical scenarios involving technetium-99m bone scintigraphy for ATTR-CM.
• Integration of scintigraphic findings with clinical features, biomarkers, and echocardiography.
• Application of cardiac magnetic resonance (CMR) imaging for differential diagnosis and tissue characterization.

Main Results:

• Scintigraphy can reveal incidental findings requiring further investigation.
• Confounding factors like left ventricular hypertrophy can complicate diagnosis.
• CMR provides essential complementary data for refined diagnosis and prognosis.

Conclusions:

• A combined approach using scintigraphy, clinical data, and CMR is fundamental for accurate ATTR-CM diagnosis.
• Awareness of potential pitfalls is essential for optimal patient management.
• Integrated diagnostic strategies improve diagnostic accuracy and therapeutic decisions.