心脏兴奋剂

例句：

1. 1. The medication was designed to stimulate the heart's natural rhythm.
   这种药物被设计来刺激心脏的自然节律。
2. 2. He took a heart stimulant before his surgery to help him stay awake.
   他在手术前服用了心脏刺激剂，以帮助他保持清醒。
3. 3. The researcher found that certain drugs could be used as heart stimulants to treat anxiety disorders.
   研究者发现某些药物可以作为心脏刺激剂用于治疗焦虑障碍。