Comparison of cardiac amyloidosis due to wild-type and V122I transthyretin in older adults referred to an academic medical center
Abstract
Aims: In the USA, transthyretin cardiac amyloidosis usually results from ‘wild-type’ transthyretin (senile cardiac amyloidosis [SCA]) or the V122I variant. Patients & methods: We compared presentations and outcomes among SCA and V122I patients referred to the Center for Advanced Cardiac Care at Columbia University Medical Center (NY, USA) between 2001 and 2012. Results: V122I patients were younger (mean: 71 years, standard deviation [SD]: 7) than SCA patients (mean: 77, SD: 6; p = 0.0002) and 96% were black compared with 3% of SCA patients (p < 0.0001). Average ejection fraction was lower among V122I patients (mean: 25% [SD: 12] vs mean: 47% [SD: 15]; p = 0.0001), as was mean cardiac index. Median time to death or orthotopic heart transplant was 36.4 months for V122I patients and 66.5 for SCA patients (p = 0.09). Conclusion: In this study of patients with transthyretin cardiac amyloidosis, V122I patients presented to a tertiary academic medical center at a younger age than SCA patients but had higher levels of cardiac dysfunction, despite genetic screening availability. There was a trend toward shorter time to orthotopic heart transplant or death among V122I patients. Whether this is a result of a different biologic progression or late diagnosis requires further study.
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