Concomitant Transthyretin Amyloidosis and Severe Aortic Stenosis in Elderly Indian Population

BACKGROUND: Prevalence of both degenerative severe aortic stenosis (AS) and transthyretin cardiac amyloidosis (ATTR-CA) increases with age. Dual disease (AS+myocardial ATTR-CA) occurs in significant proportion of patients undergoing surgical aortic valve replacement (SAVR). OBJECTIVES: This study aimed to determine the prevalence of ATTR-CA in severe AS in the Indian population, identify noninvasive predictors of its diagnosis, and understand its impact on prognosis. METHODS: Symptomatic severe AS patients aged ≥65 years undergoing SAVR were enrolled. ATTR-CA diagnosis was based on preoperative 99m-technetium pyrophosphate (PYP) scan and intraoperatively obtained basal interventricular septum biopsy for myocardial ATTR-CA, and excised native aortic valve for isolated valvular ATTR-CA. Primary amyloidosis was excluded by serum/urine protein electrophoresis with serum immunofixation. CONCLUSIONS: Dual disease is not uncommon in India. Isolated valvular amyloidosis in severe AS is much more common.