Insights into cardiac amyloidosis screening in TAVI from a Greek/Cypriot Cohort: the GRECA-TAVI registry

Abstract Background Transthyretin amyloid cardiomyopathy (ATTR-CM) is a disease with a poor prognosis and an unknown prevalence in the general population. Specific patient subgroups are at higher risk, such as patients with severe aortic stenosis (AS). Purpose To investigate the prevalence of ATTR-CM in Greek and Cypriot patients with severe AS that undergo Transcatheter Aortic Valve Implantation (TAVI). Methods A total of eight (n=8) tertiary hospital centers from Greece and Cyprus formed part of the GRECA-TAVI registry to evaluate the prevalence of ATTR-CM in patients undergoing TAVI. The inclusion criteria were diagnosis of severe AS in the presence of left ventricular hypertrophy (i.e. ≥12mm). Patients were referred for ATTR-CM screening by Tc99m-DPD or Tc99m-PYP bone scintigraphy. A complete hematologic workup was performed in all patients to rule out plasma cell dyscrasias. Cases with equivocal bone scintigraphy findings were not included in analysis. Results A total number of n=303 AS patients were screened from January 2023 until February 2024. Screening for CA with Tc99m-DPD/PYP bone scintigraphy and hematological tests was complete for all the patients included in the study. A positive bone scan (i.e. Perugini scale 2 or 3) was found in n=31 or 10.2% of the patients. The mean age of patients was not significantly different between AS patients with and without ATTR-CM (82,25 ±1,8 vs. 81,21 ±0,44 respectively, p=0.478). A male predominance was found in the ATTR-CM subgroup, although this was not statistically significant compared to non-ATTR-CM patients (%male: 64.5% vs. 49.3%, respectively, p=0.13). ATTR-CM patients had a lower LVEF compared to non-ATTR-CM patients (47.5% ±2.13 vs. 55% ±0.75, p=0.046). Conclusions The prevalence of ATTR-CM in this cohort of patients with severe AS undergoing TAVI was ~10%. These findings call for the implementation of national screening strategies for ATTR-CM which still remains significantly underdiagnosed in many geographic parts of the globe.