摘要:
An indole derivative represented by formula (1),
wherein A is a group
or
wherein R¹⁰ is hydrogen or lower alkyl, dotted lines may optionally be resent, and R¹-R⁹ represents various substitutional groups. The compound (1) exhibits a positive inotropic action on cardiac muscle, an anti-arrhythmic action, and a vasodilation action without increasing the heart rate. A heart affection therapeutic agent comprising this compound as an effective component is extremely effective for treating heart failures and arrhythmia.