This study will assess whether CA-4F can improve diagnosis of ATTR-CM in a community cardiology setting when used to screen electronic medical record data for patients suitable for follow-up investigations.

This is a prospective multicentre observational study to assess whether CA-4F can improve diagnosis of ATTR-CM in a community cardiology setting when used to screen electronic medical record data for patients suitable for follow-up investigations.

The algorithm will be used to screen electronic health records of participating cardiologists for patients suitable for PYP scans to investigate potential ATTR-CM and determine its positive predictive value.

Input parameters to the algorithm will be extracted from the pseudonymized electronic health records of patients who visited participating cardiologists in the 12 months preceding their enrolment.

The records of patients with elevated pre-test likelihood of ATTR-CM will be queried for Canadian Heart Failure Society red flag symptoms to facilitate clinical review. Participating cardiologists will review the red flag symptoms and electronic health records of patients with elevated pre-test likelihoods and document whether further investigation with PYP is clinically justified with supporting rationale.

Patients for which further investigation is clinically justified will be referred for confirmatory testing and the results of additional investigations will be documented. The positive predictive values of "moderate", "high" and "very high" CA-4F Risk Scores will be calculated by determining the percentage of those patients for which further investigations were performed and resulted in diagnosis of ATTR-CM.

Inclusion Criteria:

• Licensed cardiologist in the Canadian provinces of Ontario, Saskatchewan or British Columbia
• Outpatient cardiology practice with ≥1,200 unique patients annually
• Have used an electronic medical record system for ≥36 months from enrollment
• Currently subscribed to the Advanced Computing Platform by Ensho Health or using a cloud-hosted electronic medical record system compatible with the Apollo Electronic Data Capture System
• Experience with the clinical management of ATTR-CM
• Access to PYP scanning for follow-up investigations
• Previous participation in clinical studies

Exclusion Criteria:

• Predominantly hospital-based cardiology practice
• Have used an electronic medical record system for <36 months from enrollment
• Electronic medical record system incompatible with the Apollo Electronic Data Capture system
• No prior experience with the clinical management of ATTR-CM
• No access to PYP scanning for follow-on investigations
• No prior participation in clinical studies