The invention relates to arylated furane and thiophene carboxylic acid amides, a method for the production thereof, the use thereof as medicaments, in addition to pharmaceutical preparations containing the compounds of formula (Ia) and (Ib) wherein X, R(1), R(2), R(3), R(4), R(5), R(6), R(7), R(30) and R(31) have the same meaning as cited in the claims. According to the invention, the compounds are particularly suitable as novel anti-arrhythmic active ingredients, particularly for the treatment and prophylaxis of atrial arrhythmia for example, atrial fibrillation, AF, or atrial flutter.