Analysis of Lumbar Spine Stenosis Specimens for Identification of Transthyretin Cardiac Amyloidosis

This is a multicenter, prospective cohort study aimed at facilitating identification of individuals with ATTR-CA. Investigators will identify subjects with previous LSS surgery who have evidence of TTR amyloid deposits in spinal specimens. Subjects with localized TTR in spinal tissue will be invited to an on-site visit and be evaluated for the presence of clinical manifestations of ATTR cardiac amyloidosis (ATTR-CA).

Subjects will undergo nuclear scintigraphy, TTR genetic test, a clinical evaluation, electrocardiogram, and echocardiogram. Quality of life questionnaires will also be administered. Subjects who have myocardial retention of the imaging radiotracer with a Perugini score equal to 2 (uptake equal to bone) or 3 (uptake greater than bone) and confirmation by SPECT or SPECT/CT that the uptake is myocardial in nature and have no evidence of monoclonal proteins will be diagnosed with ATTR-CA.

This study is to be conducted at five study sites: Boston Medical Center, Cedars Sinai Medical Center, Cleveland Clinic, Columbia University Irving Medical Center, and Tufts University Medical Center. The Mayo Clinic will serve a Pathology research core to analyze spine specimens.

Most of the subjects are expected to complete all the study procedures and questionnaires on a single day.

Up to 1663 patients will be consented in this study to have spinal specimens examined for the presence of amyloid by Congo Red at the Mayo Clinic core lab. From the pool of subjects with amyloid detected (which anticipate will be 33% or at least 544), the investigators expect to recruit 163 participants to undergo cardiac phenotyping (Tc99m and cardiac evaluation). Among the 163 participants who undergo cardiac phenotyping, 98 will have TTR as the precursor protein identified by mass spectrometry and 65 will have an indeterminant precursor protein by mass spectrometry.