The use of early beta-blocker therapy in acute MI reduces the risks of reinfarction and ventricular fibrillation, but increases the risk of cardiogenic shock, especially during the first day or so after hospitalisation. Consequently, it may generally be prudent to consider starting beta-blocker therapy in hospital only when the haemodynamic condition following MI has stabilized (and then, based on previous evidence, to continue such therapy long-term following discharge).