Disclosed herein is a combination therapy for the treatment of heart failure using a myocardial myosin activator such as omecamtivecarbyl and a sinoatrial node If current inhibitor such as ivabradine. Also disclosed herein are compositions comprising a myocardial myosin activator and a sinoatrial node If current inhibitor. [Selection figure] Noneオメカムチブメカルビル等の心筋ミオシン活性化剤及びイバブラジン等の洞房結節If電流阻害剤を用いた、心不全の治療ための併用療法を本明細書に開示する。また、心筋ミオシン活性化剤及び洞房結節If電流阻害剤を含む組成物も本明細書に開示する。【選択図】なし