ATTR cardiac amyloidosis after lumbar spinal stenosis- a prospective cohort study

Abstract Background Systemic wild type transthyretin (ATTRwt) amyloidosis is underdiagnosed and generally diagnosed in manifest cardiac disease. Lumbar spinal stenosis (LSS) might be an early sign of ATTRwt and a possible screening target for early diagnosis. Aim To characterize patients with transthyretin amyloid deposits in ligamentum flavum six years after surgery for lumbar spinal stenosis, and assess prevalence of undiagnosed cardiac amyloidosis. Materials and methods In this prospective cohort study, 21 patients who had surgery for LSS in 2016-2018 and grade 3-4 ATTR deposits in ligamentum flavum, without manifest cardiac amyloidosis (CA) were followed up in 2022-2023, including biomarkers and multimodality cardiac imaging. Results Median age at follow-up was 79 years and 62% were male; 16% (3/19) of patients had DPD-scintigraphy and were diagnosed with ATTRwt cardiac amyloidosis. 48% (10/21) had a history of other tenosynovial conditions that associate to ATTRwt amyloidosis. on echocardiography. Conclusion In this prospective cohort study, 16% of patients were diagnosed with ATTRwt cardiomyopathy after a median of six years following surgery for lumbar spinal stenosis. These findings strengthen the hypothesis that LSS is a possible manifestation of ATTRwt amyloidosis and that analysis for amyloid in connective tissue and subsequent cardiac follow-up is of value.