**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Nicolas Piriou, Nantes University Hospital, Nantes, France

**Main Body of the Abstract**
Background: Recognition of transthyretin amyloid cardiomyopathy (ATTR-CM) is increasing due to advances in cardiac imaging and diagnostic strategies, but questions remain regarding disease frequency. In the TTRACK study, we aimed to determine the prevalence of ATTR-CM in patients with unexplained hypertrophic cardiomyopathy (HCM).
Methods: In this multicenter, non-interventional epidemiological study (ClinicalTrials.gov: NCT03842163), ATTR-CM prevalence was analyzed in patients ≥50 years of age with HCM(LV maximum wall thickness ≥15 mm on echocardiogram) of unknown etiology. After technetium-99m (99mTc)-DPD/-PYP/-HMDP–labelled bone scintigraphy, patients with low (Perugini grade 1) or moderate/high (grade 2/3) cardiac uptake were assessed. Tests for monoclonal protein abnormalities and gene sequencing were also performed.
Results: Among 766 patients who satisfied inclusion criteria and had scintigraphy data, mean (SD) age was 72.3 (10.6) years, and 69.6% were male. Based on moderate/high cardiac uptake, 208/766 (27.2%) patients had cardiac amyloidosis (CA) (Fig. 1A). A total of 49/766 (6.4%) had monoclonal protein abnormalities and were suspected to have ATTR amyloidosis plus monoclonal gammopathy of undetermined significance (MGUS) or light chain amyloidosis with bone tracer cardiac retention; 144/766 (18.8%) did not have these abnormalities and were identified as having ATTR-CM (Fig. 1B). In the latter group, 11/144 (7.6%) had variant ATTR-CM (Fig. 1C).
Discussion: In this final analysis of the TTRACK study, 27% and 19% of patients ≥50 years of age with unexplained HCM had scintigraphy findings suggestive of CA and ATTR-CM, respectively. Obtaining more information on prevalence is essential to improving disease knowledge and detection.



**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Nicolas Piriou, Nantes University Hospital, Nantes, France

**Main Body of the Abstract**
**Background:** Recognition of transthyretin amyloid cardiomyopathy (ATTR-CM) is increasing due to advances in cardiac imaging and diagnostic strategies, but questions remain regarding disease frequency. In the TTRACK study, we aimed to determine the prevalence of ATTR-CM in patients with unexplained hypertrophic cardiomyopathy (HCM).
**Methods:** In this multicenter, non-interventional epidemiological study (ClinicalTrials.gov: NCT03842163), ATTR-CM prevalence was analyzed in patients ≥50 years of age with HCM(LV maximum wall thickness ≥15 mm on echocardiogram)_ _of unknown etiology. After technetium-99m (99mTc)-DPD/-PYP/-HMDP–labelled bone scintigraphy, patients with low (Perugini grade 1) or moderate/high (grade 2/3) cardiac uptake were assessed. Tests for monoclonal protein abnormalities and gene sequencing were also performed.
**Results:** Among 766 patients who satisfied inclusion criteria and had scintigraphy data, mean (SD) age was 72.3 (10.6) years, and 69.6% were male. Based on moderate/high cardiac uptake, 208/766 (27.2%) patients had cardiac amyloidosis (CA) (**Fig. 1A**). A total of 49/766 (6.4%) had monoclonal protein abnormalities and were suspected to have ATTR amyloidosis plus monoclonal gammopathy of undetermined significance (MGUS) or light chain amyloidosis with bone tracer cardiac retention; 144/766 (18.8%) did not have these abnormalities and were identified as having ATTR-CM (**Fig. 1B**). In the latter group, 11/144 (7.6%) had variant ATTR-CM (**Fig. 1C**).
**Discussion:** In this final analysis of the TTRACK study, 27% and 19% of patients ≥50 years of age with unexplained HCM had scintigraphy findings suggestive of CA and ATTR-CM, respectively. Obtaining more information on prevalence is essential to improving disease knowledge and detection.



Prevalence of transthyretin amyloid cardiomyopathy in patients with hypertrophic cardiomyopathy: Final analysis of the TTRACK study OB8 (#18)

We invite you to attend the XIX International Symposium on Amyloidosis to be held in Rochester, MN.

This symposium is organized as a hybrid meeting (with the focus on in-person) held from Sunday, May 26 through Thursday, May 30, 2024.

Together with the ISA Board and members of Mayo Clinic, a very attractive scientific hybrid program is being planned. The program will cover a variety of types of systemic amyloidosis: ATTR (hereditary and wild-type), AL (light-chain), AA and less frequent forms. There will be key lectures, specific symposia including those company sponsored, oral presentations and poster sessions of accepted abstracts.

COURSE DESCRIPTION
This program will provide a comprehensive review of state-of-the-art education in systemic amyloidosis: basic science, pathophysiology, diagnosis, current and emerging treatments. Scientific presentations will include competitive oral and poster abstracts. The rapid evolution of scientific discovery and expanding treatment options has created tremendous interest in the field and this meeting will fill and important gap in educating scientists and clinicians.