Main Body of the Abstract
Background
The natural disease progression of ATTR Cardiac Amyloidosis (ATTR-CA) is a complex, multi-faceted pathophysiologic process involving both local and systemic consequences of insoluble protein deposition. Predictors of disease progression and severity are vital in employing early, aggressive management strategies. The aim of this study is to stratify patients with ATTR-CA according to NT-proBNP levels at the time of diagnosis and investigate whether any differences exist in their clinical characteristics.
Methods
We included 192 patients with a confirmed diagnosis of ATTR-CA evaluated between 2/2016 and 12/2022 with NT-proBNP values. Patients were stratified into quartiles at the time of ATTR-CA diagnosis and their clinical characteristics were compared using appropriate testing methods.
Results
In this study of 192 patients with confirmed ATTR-CA (mean age 78.3 ± 8.5, 90.6% males), the median [IQR] NT-proBNP measured 1884.5 [817.5-3737.3] pg/ml. When stratifying patients according to NT-proBNP quartiles, patients in higher quartiles tended to be older (P=0.2) and had similar comorbidity profiles except for a higher prevalence of atrial fibrillation (P<0.001). At presentation, those in the higher quartiles had worse NYHA functional classification (P<0.001), lower glomerular filtration rate (P<0.001), and more impaired left ventricular ejection fraction. Use of heart failure therapies, including tafamidis, were no different among the subsets.
Conclusion
This study adds to the current body of literature on the clinical relevance of NT-proBNP to ATTR-CA disease severity and warrants more complex, multidisciplinary interventions in patients with higher NT-proBNP at the time of ATTR diagnosis.

**Main Body of the Abstract**
**Background**
The natural disease progression of ATTR Cardiac Amyloidosis (ATTR-CA) is a complex, multi-faceted pathophysiologic process involving both local and systemic consequences of insoluble protein deposition. Predictors of disease progression and severity are vital in employing early, aggressive management strategies. The aim of this study is to stratify patients with ATTR-CA according to NT-proBNP levels at the time of diagnosis and investigate whether any differences exist in their clinical characteristics.
**Methods**
We included 192 patients with a confirmed diagnosis of ATTR-CA evaluated between 2/2016 and 12/2022 with NT-proBNP values. Patients were stratified into quartiles at the time of ATTR-CA diagnosis and their clinical characteristics were compared using appropriate testing methods.
**Results**
In this study of 192 patients with confirmed ATTR-CA (mean age 78.3 ± 8.5, 90.6% males), the median [IQR] NT-proBNP measured 1884.5 [817.5-3737.3] pg/ml. When stratifying patients according to NT-proBNP quartiles, patients in higher quartiles tended to be older (P=0.2) and had similar comorbidity profiles except for a higher prevalence of atrial fibrillation (P<0.001). At presentation, those in the higher quartiles had worse NYHA functional classification (P<0.001), lower glomerular filtration rate (P<0.001), and more impaired left ventricular ejection fraction. Use of heart failure therapies, including tafamidis, were no different among the subsets.
**Conclusion**
This study adds to the current body of literature on the clinical relevance of NT-proBNP to ATTR-CA disease severity and warrants more complex, multidisciplinary interventions in patients with higher NT-proBNP at the time of ATTR diagnosis.

Clinical Relevance of NT-Pro BNP at the Time of ATTR Cardiac Amyloidosis Diagnosis PC59 (#237)

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.