Occult senile cardiac amyloid in severe calcific aortic stenosis is not rare and has a poor prognosis: a 146 patient CMR biopsy study

Background Severe degenerative calcific aortic stenosis (cAS) affects 3% of the over 75 year-olds and leads to heart failure and death unless the valve is replaced. Coexisting cardiac amyloid typically wild-type Transthyretin (wtATTR) has been reported but has not been systematically studied: its prevalence and prognostic significance are unknown. Multiparametric CMR (function, LGE, T1 and ECV mapping) has high sensitivity and specificity for cardiac amyloidosis. We sought, in cAS, to define the prevalence of occult cardiac amyloid by biopsy, subtype it, explore its CMR presentation and understand its prognostic significance.