TNNI3K and sinoatrial nodal reentry tachycardia: This is, however, unlikely considering the published TNNI3K-p.Glu768Lys families where a similar phenotype was observed.4 Another potential cause could be that a potential signal for atrioventricular-nodal reentry tachycardia in TNNI3K variant carriers was lost in the more broad SVT phenotype obtained from the UK Biobank.