A detailed understanding of drug-channel interaction is therefore essential in the perspective of improving HCN isoform-specific selectivity of block, particularly since differential isoform distribution in heart and brain may underlie isoform-dependent pathologies including for example arrhythmias, epilepsy, motor learning defects, pain transmission [7], [8], [27], [28]. Here, MALAT1 is linked to cardiac arrhythmia.