A man, 43 years of age, presents to his general practitioner with a 6 day history of sore throat. There are no other symptoms of an upper respiratory tract infection. In passing, the patient mentions that 6 days ago he experienced an episode of exertional chest pain. On further questioning it is found the chest pain was central with no radiation, it lasted 30 minutes, resolved spontaneously and was associated with nausea. He did not seek medical assessment at the time and has no cardiac history. He takes no regular medication and has no allergies. He is an exsmoker with a 15 pack-year history (he quit 7 years ago) but has no other known cardiac risk factors. He does not drink alcohol or take illicit drugs. On examination, he appears well built with a body mass index of 27. He is not in distress apart from a moderate sore throat. He is afebrile. His heart rate is 66 bpm, regular and his blood pressure is 122/80 mmHg. His tonsils and uvula are neither inflamed nor swollen. He has no cervical lymphadenopathy. His lungs are clear on auscultation and his heart sounds are dual with no murmur. His electrocardiogram is shown in Figure 1.