What is a PYP Scan?
A PYP (pyrophosphate) scan is a nuclear medicine imaging study that uses technetium-99m pyrophosphate radiotracer to detect cardiac amyloidosis by identifying abnormal amyloid protein deposits in the heart muscle. 1
Primary Clinical Application
The PYP scan is specifically used to diagnose cardiac amyloidosis, particularly transthyretin (ATTR) cardiac amyloidosis, which is a critical risk factor for chemotherapy-induced cardiotoxicity in oncology patients. 1
What the Scan Entails
- Radiotracer injection: Technetium-99m pyrophosphate is administered intravenously 1
- Imaging timing: Images are typically acquired 1-3 hours after radiotracer injection to allow for optimal target-to-background ratio 1
- Detection mechanism: The pyrophosphate compound binds to calcium deposits and amyloid fibrils in the myocardium, creating areas of increased radiotracer uptake that appear as "hot spots" on imaging 1
- Imaging modality: SPECT (single-photon emission computed tomography) or planar imaging is used to visualize the heart 1
Clinical Context and Limitations
- The ACR Appropriateness Criteria note that while PYP scanning is established for cardiac amyloidosis evaluation, there is no relevant literature supporting its use for baseline cardiac risk stratification before initiating oncologic therapy in asymptomatic patients. 1
- The scan is not used for pancreatic imaging or pancreatic cancer diagnosis—this is a common source of confusion, as "PYP" might be mistakenly associated with "pancreatic" imaging 1
Important Distinction
Do not confuse PYP cardiac scanning with pancreatic PET imaging using FDG (fluorodeoxyglucose), which is an entirely different modality used in oncology for staging certain cancers. 1