Registry of Patients with Suspected Amyloidosis in Heart Failure

Observational, cohort study with a duration of two years to recruit at least 150 patients in the group with CA, and a follow-up of two years. The investigators estimate a sample size of at least 150 patients in the Group 1 (CA confirmed), and a total of 450 patients.

The primary objectives of this study are:

• To evaluate differential characteristics between two groups of patients with Heart

Failure with clinical suspicion of Cardiac Amyloidosis (CA):

• Group 1: Patients in whom CA is confirmed.
• Group 2: Patients in whom CA is ruled out.

• Clinical, laboratory, electrocardiographic, echocardiographic characteristics, and other studies (MRI, biopsies, etc.) will be compared between both groups.

The secondary objectives are:

• To evaluate the clinical and complementary test data on which the suspicion of the diagnosis of AC has been based.
• To identify prognostic differences between both groups by comparing readmission rates, mortality and other events of patients with CA and without CA in a period of two years.

The patients included in the study are elderly patients, of both genders, with heart failure, who have undergone an echocardiogram in the last 24 months, with a clinical suspicion of amyloidosis.

All patients who meet inclusion criteria will be included from January 2022 to December 2023.

The following studies are performed on each patient:

• Clinical, laboratory, electrocardiographic, echocardiographic.
• Bone-cardiac scintigraphy.
• Laboratory test to rule out monoclonal protein.
• The number of readmissions, emergency room visits, and mortality in the 24 months following their inclusion will be recorded.

A descriptive analysis of the data and a comparative analysis will be made in relation to different variables. The association of different variables with readmission and mortality data will be assessed using univariate and multivariate analysis. An analysis of survival curves will also be performed using the Kaplan-Meier method using the log-rank test.

Inclusion criteria

• Age ≥ 18 years.
• Both genders.
• Heart Failure (2021 European Society of Cardiology criteria)
• Any LVEF value.
• Outpatients or hospitalized patients in Internal Medicine Units
• Patients with suspicion criteria proposed by the European Society of Cardiology:

• Ventricular hypertrophy ≥ 12 mm

And one or more of the following criteria:

• Heart failure in ≥ 65 years
• Aortic stenosis in ≥ 65 years
• Hypotension or Normotensive if previously hypertensive
• Sensory involvement, autonomic dysfunction
• Peripheral polyneuropathy
• Proteinuria
• Skin bruising (eg, periorbital purpura)
• Bilateral carpal tunnel syndrome
• Ruptured biceps tendon
• In CMR: Subendocardial / transmural late gadolinium enhancement (LGE), or increased extracellular volume (ECV)
• In ECO: Reduced longitudinal strain with apical sparing
• Reduced QRS voltage to mass ratio
• Pseudo Q waves on ECG
• Atrioventricular conduction disease
• Possible family history of ATTRv

Exclusion criteria

• Refusal to participate in the registry