ATTR-CM

This multicenter, prospective, single-arm, interventional study will enroll about 4,000 adult patients at high risk of ATTR amyloidosis from around 50 sites in China. Eligible patients are aged ≥60 years and have documented symptomatic heart failure with left ventricular ejection fraction ≥40% and LVH. Exclusion criteria include known etiologies of myocardial diseases, anomalies of serum free light chain or serum immunofixation electrophoresis, acute myocardial infarction within 6 months before screening, and inability to undergo 99mTc-PYP. Patients will undergo a 14-week diagnostic process. The study intervention involves knowledge training, operation training and post-training verification among investigators. Knowledge training for CV department investigators will cover disease-specific knowledge, standard diagnostic pathways, and genetics; training for investigators in echocardiology (ECHO) and nuclear medicine departments will focus on disease knowledge, standardized operating procedures (SOPs), and imaging parameter reporting. Operation training includes hands-on training in SOPs and image interpretation for ECHO and nuclear medicine investigators. Post-training verification will assess site-level compliance. Extra training will be arranged if quality audit is off target. The primary endpoint is the proportion of patients diagnosed with ATTR amyloidosis in high-risk populations. Secondary endpoints include the proportion of patients with ATTRwt amyloidosis, concordance between local investigators and central reviewers in ECHO and 99mTc-PYP readings, and genotype distribution. All analyses will be descriptive with no pre-planned hypotheses. Risk factors associated with 99mTc-PYP-diagnosed ATTR amyloidosis will be analyzed via logistic regression models.

Transthyretin amyloid cardiomyopathy (ATTR-CM), is a heart muscle disease that's stops the heart muscle working properly. With an ageing population, it is increasingly common but untreated, it has a poor prognosis. Several novel expensive treatments have become available, although we do not understand exactly how they work and why some patients respond, and others do not. The challenge is to develop better methods for monitoring the effects of these treatments, maximizing their benefits and cost-effectiveness. In I-CARE we aim to bring a new imaging technique, named 18F-fluoride PET, to the clinic and thereby improve the care of patients with ATTR-CM. Hypotheses: 1. A delayed imaging protocol and state-of-the-art PET motion correction will optimise 18F-fluoride imaging in ATTR-CM and provide a clear threshold in myocardial TBR values for the diagnosis of ATTR-CM. 2. Optimised 18F-fluoride PET will provide a quantitative marker of the ATTR-CM burden that will allow disease progression and treatment response to be tracked. 3. Myocardial 18F-fluoride TBR values will reduce in patients responding to tafamidis treatment and increase in non-responders and patients not receiving therapy

The MaesTTRo study aims to enroll a global cohort of patients with transthyretin (ATTR) amyloidosis to longitudinally observe the natural course of the disease and describe real-world treatment patterns and outcomes. In addition, information on the effectiveness of ATTR amyloidosis treatments, including eplontersen, which is a ligand-conjugated antisense oligonucleotide gene silencing treatment targeting activity against both the mutant and wild-type TTR protein, will be collected.

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.