A Multicenter Study on Atrioventricular Regurgitation in Transthyretin Amyloid Cardiomyopathy: Definition, Prevalence, and Prognostic Impact.

Definition and Prognosis of Atrioventricular Regurgitation in Transthyretin Amyloid Cardiomyopathy - a Prospective International Multicenter Study

The objective of this prospective registry study is to comprehensively characterize the prevalence, (semi-) quantitative parameters, and associated clinical outcomes of mitral (MR) and tricuspid regurgitation (TR) in patients diagnosed with transthyretin amyloid cardiomyopathy (ATTR-CM). The study further aims to develop and implement new grading standards for the quantitative assessment of regurgitation severity, tailored to the distinct hemodynamic profile of ATTR-CM. This approach seeks to address the limitations of current regurgitation severity classifications, which do not adequately reflect the unique pathophysiology of a restrictive phenotype as seen in ATTR-CM.

Inclusion Criteria:

• Diagnosis of ATTR-CM according to current diagnostic criteria
• Comprehensive baseline echocardiographic assessment, including (semi-)quantitative mitral and tricuspid regurgitation (MR/TR) parameters, performed within ±6 months of diagnosis
• Age ≥ 18 years
• Willingness to participate in the study and provide informed consent

Exclusion Criteria:

• Severe aortic valve disease requiring intervention
• Inability to provide informed consent or participate in study follow-up