A 48 year old man presents with crushing central chest pain for the last 90 minutes, which radiates to the jaw and down the left arm. He has a 20-pack year smoking history and Hypertension. He is not on regular medications, having declined antihypertensives last year.
On examination, his blood pressure is 162/94 mmHg, his heart rate is 108 beats per minute, his respiratory rate is 16 breaths per minute and his oxygen saturation is 93% in air.
You have already called an ambulance, administered Glyceryl Trinitrate spray and an antiplatelet. What is the next most appropriate management step?