Prevalence and prognostic significance of restriction versus systolic dysfunction in patients with transthyretin and light chain cardiac amyloidosis

Abstract The tenet of cardiac amyloidosis (CA) as a paradigm of heart failure with restrictive ventricular physiology and preserved systolic function has come under scrutiny. Thus, we aimed to evaluate the prevalence and clinical significance of left ventricular (LV) systolic dysfunction versus restriction in a large real-world cohort with CA, assessed at the time of diagnosis. Methods This is a multicenter retrospective analysis including 540 transthyretin (ATTR)-CA and 280 light chain (AL)-CA. Patients were divided into 3 phenotypes: 1) preserved LV function: LV ejection fraction (EF) ≥50% associated with grade 0/I diastolic dysfunction; 2) restriction: LV-EF≥50% associated with grade II/III diastolic dysfunction; 3) systolic dysfunction: LV-EF<50% irrespective of diastolic function. We analysed progression from preserved LV function towards the other two phenotypes and their survival. Results In ATTR-CA, prevalence of preserved LV function was 27%, restriction was 44% and systolic dysfunction was 28%. Among patients with preserved LV function, annual conversion rate to restriction was 24% and to systolic dysfunction was 17%. At 3 years, survival free from all-cause mortality was 88%, 76% and 63% respectively (figure A). In AL-CA, prevalence of preserved LV function was 30%, restriction was 49% and systolic dysfunction was 20%. Among patients with preserved LV function, annual conversion rate to restriction was 28% and to systolic dysfunction was 8%. At 3 years, survival free from all-cause mortality was 56%, 39% and 29% respectively (figure B). Conclusions Restriction was the presenting phenotype in less than half of patients, while systolic dysfunction in approximately one quarter. The annual rate of progression form preserved LV function towards restriction or systolic dysfunction was high. In ATTR systolic dysfunction was associated with worse outcome, compared to restriction; in AL both restriction and systolic dysfunction were associated with equally ominous outcome.