Novartis AG has synthesized naphthyridinone derivatives acting as K(ir) 3.1/3.4 (GIRK1/4; KCNJ3/5) IKACh channel blockers reported to be useful for the treatment of bradyrhythmic arrhythmia, bradycardia, atrial fibrillation, heart block, hypotension, primary aldosteronism, sick sinus syndrome and vasovagal syncope, among others.