Alexios S. Antonopoulos, Theodoros Tsampras, Panagiotis Kanatas, Nikolaos Ktenopoulos, Maria Koutelou, Ιoannis Panagiotopoulos, Dimitrios Kyriakopoulos, Leonidas Koliastasis, Marios Ioannidis, Christos Eftychiou, Ιoannis Iakovou, Aikaterini Naka, Ilias K. Gartzonikas, Λάμπρος Λάκκας, Dimitrios Tziakas, Achilleas Zacharoulis, Georgios Katsimagklis, Konstantinos Aznaouridis, Sophia Vaina, George Latsios, Alexandra Frogoudaki, Stella Vakrou, Angelos G. Rigopoulos, Ilias Ninios, Evangelos Oikonomou, Spyridon Maragkoudakis, Kimon Stamatelopoulos, Efstathios Kastritis, Gerasimos Filippatos, Ioannis Kanakakis, George Kochiadakis, Lambros K. Michalis, Emmanouil Vavouranakis, Konstantinos Toutouzas, Konstantinos Tsioufis, Charalambos Vlachopoulos, Alexios S. Antonopoulos, Konstantinos Aznaouridis, George Benetos, Christina Chrysochoou, Vasiliki Gardiokioti, Nikolaos Ioakeimidis, Panagiotis Kanatas, Konstantinos Karampinos, Alexandros Kasiakogias, Themistoklis Katsimichas, Leonidas Koliastasis, Freideriki-Eleni Kourti, Nikolaos Ktenopoulos, Dimitrios Kyriakopoulos, George Latsios, George Lazaros, Panteleimon Ntoskas, Dimitrios Syrseloudis, Dimitrios Terentes-Printzios, Theodoros Tsampras, Konstantinos Tsioufis, Sofia Vaina, Charalambos Vlachopoulos
OBJECTIVE: Transthyretin cardiac amyloidosis (ATTR) is prevalent among patients undergoing transcatheter aortic valve implantation (TAVI) for severe aortic stenosis (AS). We aimed to develop and validate a risk score for predicting ATTR in this context. METHODS: In the prospective multicenter GRECA-TAVI registry, 500 patients with severe AS scheduled for TAVI were screened for ATTR using technetium-99m-labeled 3,3-diphosphono-1,2-propanodicarboxylic acid or pyrophosphate bone scintigraphy in 12 tertiary hospitals, from January 1 to December 31, 2024. Clinical, echocardiographic, and electrocardiographic variables were recorded. A logistic regression-derived integer-based risk score was developed in a training cohort (n = 350) and validated in a validation cohort (n = 150). Model performance was evaluated using discrimination, calibration, and decision curve analyses. RESULTS: ATTR was diagnosed in 38 (7.6%) patients. Five variables (age, sex, MWT, left ventricular ejection fraction, and intracardiac device presence) formed the basis of an 8-point risk score. The score demonstrated good discrimination (AUC = 0.75 training, 0.76 validation) and calibration (slope = 1.15). A score ≥4 identified patients with an ∼16% ATTR prevalence compared with 2.4% in those with a score <4. This threshold captured most of the ATTR cases (73%) while recommending screening for only 36% of the cohort. The decision curve analysis showed net clinical benefit across clinically relevant thresholds (5-20%) over and above a guideline-recommended approach (based on MWT ≥12 mm) or a screen-all strategy. CONCLUSION: ATTR is common in patients with severe AS undergoing TAVI. A simple bedside score using routinely available variables effectively identifies those patients at risk for ATTR. Selective screening using this tool could improve diagnostic yield and resource allocation.