Lyme borreliosis is a tick-borne disease. Cardiac manifestations of the disease are extremely rare. We report a case of Lyme carditis in an otherwise healthy male, who presented to the Accident & Emergency Department with chest pain, dizziness and generally symptoms indicating ischaemic heart disease. This patient, without documented history of Lyme disease, acutely developed third-degree atrioventricular block, which required placement of a transvenous pacemaker and resolved when the patient was administered doxycycline.