Current practices and access to cardiac bone scans for the detection of transthyretin cardiac amyloidosis based on the results of a large national electronic survey

Background The diagnosis of transthyretin cardiac amyloidosis (ATTR-CM) requires a good collaboration between physicians to confirm the diagnosis. Purpose This study aimed to assess current practices of nuclear medicine (NM) physicians for cardiac scintigraphy with bone radiotracers and to evaluate access to cardiac bone scintigraphy in the healthcare circuit for the diagnosis of ATTR-CM. Methods A nationwide electronic survey was sent to 13 830 French physicians including 775 nuclear medicine (NM) physicians to assess their knowledge of 1. clinical signs of amyloidosis and 2. the recommended diagnostic algorithm to identify TTR cardiac amyloidosis. In addition, accessibility, appointment delays and results interpretation difficulties for each of the explorations required to confirm the diagnosis of ATTR-CM were evaluated among different medical specialists. A part of the questionnaire was exclusively dedicated to NM to understand their current practice regarding acquisitions protocols and reporting of cardiac bone scans. Results 1264 physicians including 148 NM physicians (19 % of all NM physicians contacted) completed the survey. NM physicians who answered to the survey worked in academic hospitals (35 %), general hospitals (31 %), or private practices (26 %). Cardiac bone scans using early acquisitions were performed by 20 % of NM and SPECT acquisitions by 72 %. Grading of cardiac uptake of bone tracers using the Perugini score was carried out by 93 % of the NM, but only 31% and 5% of NM systematically performed heart/whole body or heart/mediastinum signal quantification, respectively. Median (Q1; Q3) delay to obtain results for a cardiac bone scan was estimated at 2 weeks (2; 4) compared to 4 (3; 8) weeks for cardiac MRI, and 2 (2 ; 4) weeks for a biopsy. Among physicians involved in clinical management of patients with ATTR-CM, 68% rarely or never faced difficulties for cardiac scintigraphy. Main difficulties encountered by physicians were: appointment delay (60%), geographical distance (17%), interpretation (12%). Conclusions In this large French national survey, access to cardiac bone scintigraphy for patients with a suspicion of ATTR cardiac amyloidosis and quality of reports appear excellent thanks to good adherence of NM physicians to the recommended acquisition protocols for cardiac bone scans and the widespread use of the Perugini grading scale in reports. However, quantitative measurements of cardiac uptake of bone tracers were performed only in one third of bone scans underscoring room for improvement in the next procedural guidelines for cardiac bone scans.