Beta-1 receptor agonists preferentially stimulate cardiac beta-1 receptors and increase inotropy. Dobutamine is the principal clinically used drug in this category.

Beta-1 receptors couple to Gs, increasing cyclic AMP and calcium handling in cardiomyocytes. This raises contractility and usually heart rate and myocardial oxygen consumption.

Dobutamine is the key example. Dopamine and isoproterenol have beta-1 activity but belong to broader mixed or nonselective groups.

Dobutamine provides short-term inotropic support in selected low-output states, acute cardiac decompensation and cardiogenic shock when perfusion remains inadequate despite appropriate pressure and volume management.

Tachycardia, ectopic beats, atrial or ventricular arrhythmias, angina and blood-pressure changes may occur. Prolonged infusion can lead to tolerance and does not improve long-term heart-failure outcomes.

Use requires continuous haemodynamic and rhythm monitoring. Caution is necessary in obstructive hypertrophic cardiomyopathy, uncontrolled arrhythmia and active myocardial ischaemia.