A 70 year old woman suffered an out of hospital cardiac arrest whilst playing golf. She received bystander cardiopulmonary resuscitation and two shocks from an automated external defibrillator which restored spontaneous circulation. She was intubated at the scene and arrived in the resuscitation department cardiovascularly stable, well oxygenated and unconscious in the context of propofol sedation.
There was no prodrome suggestive of a specific aetiology for the cardiac arrest but information from relatives described an ex-smoker with hypercholesterolaemia and diet controlled diabetes mellitus who had previously undergone percutaneous coronary intervention (PCI) for ischemic heart disease. She took regular aspirin, statin and beta-blocker. A post resuscitation 12 lead ECG showed sinus rhythm, left axis deviation and non-specific lateral ischaemia. Troponin was elevated above 200 ng/L.
In view of this she was loaded with dual antiplatelet therapy and underwent emergency coronary angiography which demonstrated occlusion of two small branches (OM1 and PLV) but no large vessel coronary artery occlusion to explain the cardiac arrest. The occluded vessels were not stented. Subsequent echocardiogram and cardiac MRI demonstrated old circumflex territory scar but an otherwise normal heart and ultimately it was agreed that the cause of cardiac arrest was probably ventricular arrhythmia secondary to scar.
She was ventilated for 24 hours with targeted temperature management before being woken and extubated. Although she was initially confused, her neurology improved over approximately 48 hours such that she was discharged with no apparent neurological injury. An implantable cardiac defibrillator was placed prior to discharge to prevent sudden cardiac death from any future arrhythmia.
- In survivors of out of hospital cardiac arrest should we proceed to early coronary angiography with a view to PCI?
- If so, should we apply this approach to all such patients or only a subset?
- If we do proceed to early coronary angiography, should this occur before or after other investigations, specifically computed tomography (CT) of the head and chest to look for intracerebral bleed and pulmonary embolism?