Thirty-four patients with
amyloidosis proved by biopsy specimen were studied using
technetium Tc 99m pyrophosphate scintigraphy to assess its utility in the diagnosis of
amyloid heart involvement. Of 14 patients studied retrospectively, only three had intense uptake judged to be diagnostic of cardiac
amyloidosis. In a prospective analysis of 20 patients with
amyloidosis, all of whom had evidence of cardiac involvement by two-dimensional echocardiography, 17 had abnormal scans. Fourteen of the 17 scans had only 1+ or 2+ uptake, a finding that also was present in 15 of the 20 control patients (without
amyloid heart disease). Only three of the 20 patients with cardiac
amyloidosis had intense uptake that was considered unequivocal and diagnostic of
amyloidosis. Of the five patients with biopsy specimen proof of endomyocardial
amyloidosis, only one had intense uptake and one had no uptake. When intense uptake of
technetium Tc 99m pyrophosphate is found in the heart of a patient,
amyloidosis is highly likely. The technique, however, is not sufficiently sensitive to warrant routine screening of patients with
amyloidosis or
cardiomyopathies. Cross-sectional echocardiography is superior to
pyrophosphate scintigraphy for recognition of cardiac
amyloidosis.