Prevalence of transthyretin cardiac amyloidosis in elderly patients diagnosed with heart failure

Objective: There is increased interest in studying ATTR-CA, a pathology that primarily affects patients of geriatric age and is frequently underdiagnosed. We aim to establish the prevalence of ATTR-CA in a cohort of patients with a history of HFpEF and to describe its characteristics.

Methods: We conducted a prospective observational study. Patients ≥75 years, clinical history of HFpEF, atrial dilation ≥34ml/m² and left ventricular wall thickening >13mm, were included. Demographic and analytical parameters were collected, and a comprehensive geriatric assessment was performed, along with a transthoracic echocardiogram and cardiac scintigraphy. Finally, telephone follow-up was carried out at 6 and 12 months.

Results: 50 patients were recruited, mean age 86±6 years, 54% women. Age and functional class (I-II vs. III-IV) were factors associated with presenting with ATTR-CA. Patients with positive scintigraphy had a median time to admission of 5.2 months (confidence interval [CI] 95% 0-10.9), while in those with negative scintigraphy, it was 12.2 months (95% CI 11.7-12.8); log-rank: p=0.064. Patients with positive scintigraphy had a median time to the combined endpoint (death and readmission) of 1.9 months (95% CI 0-6.1), and patients with negative scintigraphy of 11.9 months (95% CI 11.7-12); log-rank: p=0.027.

Conclusions: ATTR-CA appears to be a prevalent etiology in elderly patients within the spectrum of HFpEF. Patients with a diagnosis of ATTR-CA had a shorter time to admission for HF and the combined event of death and admission than patients with a negative result on scintigraphy.