External validation of the RAISE score for the diagnosis of transthyretin cardiac amyloidosis in patients with severe aortic stenosis. AMYLOCOR registry.

INTRODUCTION AND

OBJECTIVES

Transthyretin cardiac amyloidosis (ATTR-CA) is more prevalent among patients with severe aortic stenosis (AS). The RAISE score was developed to facilitate early identification of ATTR-CA in AS. Our main goal was to prospectively validate its discriminative performance for detecting ATTR-CA in patients with AS referred for transcatheter aortic valve replacement (TAVR).

METHODS

Patients with AS referred for TAVR between 2021 and 2025 were prospectively included. All underwent 99mtechnetium-diphosphonate scintigraphy. The RAISE score was calculated to evaluate its diagnostic performance, and patients with and without ATTR-CA were compared.

RESULTS

Among the 340 patients analysed, we found 14 cases of ATTR-CA (4.1%). These patients were older (83.5 ± 6.7 vs. 79.1 ± 6.1 years; p = 0.014), and exhibited more pseudo-infarct patterns (50% vs. 10.3%; p = 0.001), lower left ventricular ejection fraction (50.1% ± 16.1% vs. 62.4% ± 14.1%; p = 0.002), reduced global longitudinal strain of the left ventricle (-11.4 ± 5.8 vs. -18.3 ± 5.2; p = 0.001), and impaired right ventricular free wall strain (-16.0 ± 6.9 vs. -20.9 ± 7.8; p = 0.044). They showed higher levels of troponin I (93 [48-203] vs. 23 [13-53] ng/L; p = 0.042) and N-terminal pro-brain natriuretic peptide (4643 [2951-22,252] vs. 1563 [667-4282] pg/mL; p = 0.014). A RAISE score ≥ 2 was associated with higher prevalence of ATTR-CA compared to scores of 0-1 (7.2% vs. 2.3%; p = 0.044). The area under the curve was 0.69 (95% CI 0.554-0.825; p = 0.016).

CONCLUSIONS

In our population, the RAISE score significantly predicted ATTR-CA with moderate accuracy, lower than originally reported. The prevalence of ATTR-CA was low. Patients with ATTR-CA exhibited higher biomarker levels and worse echocardiographic parameters.