ADRB1 and hydrops fetalis: Mirabegron was also well tolerated in combination with β1–2AR‐blockers in the BEAT‐HF trial, an association also allowed in the present Beta3‐LVH trial; such combination would not only avoid off‐target agonism at β1–2AR but may even reinforce the effects on downstream NO synthase/cGMP signalling.45 In the Beta3‐LVH trial, only unspecific β1–2–3AR‐blockers, such as propranolol or bupranolol, are not allowed, as well as nebivolol which, aside from specific β1AR blockade, is also endowed with β3AR agonist activity.