Even if based on a small number of patients (n = 7), our results are in line with these previous findings, supporting the notion that the double burden of T1DM and obesity is more deleterious in terms of atrial function than T1DM alone, supposedly through mechanisms such as increased peripheral insulin resistance (double diabetes49), and altered lipid profiles resulting in lipotoxicity of the heart50. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.