TTR and diabetes mellitus: First of all, HFpEF represents a complex and heterogeneous phenotypic set, including patients with several different comorbidities (such as diabetes, atrial fibrillation, chronic kidney disease) and with different clinical characteristics, such as those subjects with wild-type transthyretin (TTR) amyloidosis (Mohammed et al., 2014; Russo et al., 2020) who often remain underdiagnosed or misdiagnosed, being inappropriately enrolled in clinical trials and showing an unsatisfactory response to neurohormonal inhibitors (Maurer et al., 2018).