Synopsis
Recognise the time-critical electrical, pump and mechanical complications of myocardial infarction and choose the next diagnostic and escalation step.
- Electrical complications are most prominent early: ventricular tachycardia/fibrillation, bradyarrhythmia and atrioventricular block can all cause sudden deterioration.
- A new harsh pansystolic murmur with shock suggests ventricular septal rupture; an apical systolic murmur with flash pulmonary oedema suggests acute severe mitral regurgitation from papillary-muscle rupture.
- Sudden hypotension, raised JVP and pulseless electrical activity may be free-wall rupture with tamponade; absence of a loud murmur does not exclude a mechanical defect.
Key red flags
Palpitations, syncope, broad-complex tachycardia, VF or cardiac arrest; correct ischaemia, hypoxia and electrolyte disturbance while following the RCUK peri-arrest or ALS algorithm.
Investigation priorities
Detect recurrent ischaemia, ventricular arrhythmia, bradycardia or AV block.
Management branches
Shock, hypoxaemia, chest pain, arrhythmia, syncope or a new murmur
- Start ABCDE, attach defibrillator pads, obtain a 12-lead ECG, IV access, blood gas/lactate and targeted oxygen only for hypoxaemia.
- Call senior cardiology and critical care immediately; obtain bedside echocardiography without delaying resuscitation.