Researchers carried out a new multi-cohort study to understand the influence of wild-type transthyretin cardiac amyloidosis (ATTR) on aortic stenosis (AS) on AS-ATTR,.They analysed the myocardial stress, damage, function and structure by assessing the afterload-related and amyloid-related as well as age-related remodeling on the new AS-ATTR phenotype.
583 patients were included in the study and divided into 4 sample groups for comparison. 359 patients with AS, 107 with ATTR, 36 with AS-ATTR and a control group of 81 participants who were matched for age and ethnicity. For the diagnosis of amyloidosis, (Perugini grade 1 was excluded). 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scintigraphy was used for the grading. NT-pro Brain Natriuretic Peptide (BNP) was considered as a primary endpoint, and myocardial structure, function and damage were secondary endpoints.
The three disease cohort groups had greater cardiac remodelling, worsening of function and elevated NT-proBNP/high-sensitivity Troponin-T (hsTnT) than older age control groups. A higher level of NT-proBNP was seen in AS-ATTR group (2844 ng/dL) (1745, 4635 respectively) compared with AS (1294 ng/dL) (1077, 1554 respectively), whereas it wasn’t significantly different from ATTR (3272 (2552, 4197) ng/dL) group. Between the AS-ATTR and ATTR groups, prevalence of carpal tunnel syndrome, hsTnT and diastology were statistically similar but higher than AS. Left ventricular mass noted in AS-ATTR group was lesser than ATTR (139 (112, 167) which was lesser than ATTR (139 (112, 167) while it was non-significantly yet different from AS (120 (109, 130) g; p=0.179).
Researchers concluded that an early degree of amyloid infiltration is probably seen by in the AS-ATTR phenotype. However, an aggregate of AS-ATTR resembles ATTR patients. ATTR-specific treatment even after TAVI is likely to be beneficial even after of AS is resolved.