Abstract Background Wild-type transthyretin amyloidosis (ATTRwt) is a progressive condition that is often underdiagnosed. The introduction of bone scintigraphy with bisphosphonates for non-invasive diagnosis has simplified the diagnostic process of ATTRwt. However, the true impact of this method on earlier diagnosis and its effect on patient outcomes remains unclear. Purpose To compare clinical status, echocardiographic parameters, and outcomes between patients diagnosed with ATTRwt before and after the implementation of bone scintigraphy as a diagnostic tool in our region. Methods Retrospective cohort study including ATTRwt patients from our Institutional Amyloidosis Registry from 2008 to 2023. The population was divided into two groups based on the timing of diagnosis: before and after 2017, the year when bone scintigraphy was implemented at our center (Pre-bone scan era and Bone scan era). Clinical and echocardiographic characteristics at the time of ATTRwt diagnosis were collected and compared between groups. The primary outcome was a composite of all-cause mortality and heart failure hospitalization at one year follow-up. A Kaplan-Meier curve was generated to estimate the incidence of the primary endpoint in each group, and the log-rank test was used to compare the curves. Results A total of 134 patients were included. The median age was 82 76 - 86 years, with 86% male. Twenty-four patients (18%) were diagnosed in the pre-bone scan era, and 110 (82%) in the bone scan era. The annual diagnosis rate was 3 patients/year in the pre-bone scan era and 18 patients/year in the bone scan era. Patients diagnosed in the pre-bone scan era had a higher incidence of heart failure (87% vs. 62%; p=0.01) and atrial fibrillation (83% vs. 43%; p=0.02) at diagnosis, as well as higher septal thickness (18.7 mm vs. 16.9 mm; p=0.03) compared to those diagnosed in the bone scan era (TABLE). The incidence of the primary outcome was significantly higher in patients diagnosed in the pre-bone scan era compared to those diagnosed in the bone scintigraphy era (50% vs. 20%; log-rank test p= 0.003, FIGURE). Conclusion In our region, the introduction of bone scintigraphy with bisphosphonates has led to a sixfold increase in the diagnostic incidence of ATTRwt, often at earlier stages of the disease, resulting in better clinical outcomes.
Domenech et al. (Sat,) studied this question.