Validation of the Kumamoto criteria for prediction of 99m technetium pyrophosphate scintigraphy positivity as a strategy for diagnosis of transthyretin cardiac amyloidosis: A retrospective cohort study in Kochi

BackgroundEarly diagnosis of transthyretin cardiac amyloidosis (ATTR-CA) is important. The aim this study was to validate the ‘Kumamoto criteria’ for prediction technetium-99m pyrophosphate (99mTc-PYP) scintigraphy positivity.MethodsOne hundred fifty patients (median age: 79.4 years, 117 males) with possibility ATTR-CA who underwent 99mTc-PYP were assessed. We divided into 4 groups (groups score 0–3) according Kumamoto criteria by total points following 3 factors: high-sensitivity troponin T (hs-cTnT) ≥0.0308 ng/ml, left ventricle posterior wall thickness ≥13.6 mm, and wide QRS (QRS ≥ 120 ms).ResultsSeventy (46.7%) positive scintigraphy. positivity rates in 0, 1, 2, 4%, 39%, 69%, 89%, respectively. Compared original cohort, our 1 group showed a relatively high rate because hs-cTnT as one factors had ability discriminate disease. sensitivity negative predictive value ng/ml 97.1% 93.9%.ConclusionsIn Kochi validation useful predicting positivity. However, should be assessed cautiously if high.