A Multi-center Cardiac PYP Scan Registry in Taiwan

The investigators will retrospectively and prospectively collect total PYP scans that had been performed on suspected or diagnosed ATTR-CM patients in medical centers in Taiwan and follow-up at least 1 year. You are enrolled based on clinical suspicions such as "red-flag" signs using ultrasound, NT-pro BNP and clinical data according to the diagnostic algorithms. If you are with Grade 2 and 3 PYP myocardial uptake, genetic testing is arranged, serum and urine AL tests results will be confirmed. Before reading, the imaging quality will be evaluated (good quality, fair but interpretable, poor but interpretable, poor and insufficient for interpretation). All the images will be visually graded by experienced nuclear medicine physicians with consensus. It helps understand the real-world data.