A Multi-center Cardiac PYP Scan Registry in Taiwan

Amyloid deposition in the heart is called cardiac amyloidosis (CA); 95% is immunoglobulin light chain amyloidosis (AL) and transthyretin amyloidosis (ATTR). Hereditary (ATTRm) or wild-type (ATTRwt) depends on whether the ATTRm gene is mutated or not. The most common mutation in Taiwan is A97S, 80% have left ventricular hypertrophy. The good prognosis depends on early diagnosis and correct treatment strategy. Bone-avid tracers such as 99mTc-PYP/DPD/HMDP could detect CA. The mechanism is not clear yet, which may be related to the microcalcification. AL amyloidosis is mostly between visual score grade 0-2, and ATTR-CM is usually grade≥2 on PYP scan, or heart to contralateral (H/CL) ratio, and it might replace invasive myocardial biopsy. However, there are no large-scale clinical studies, lack of standardization data, and limited information in comparison between clinical and imaging parame