Acute coronary angiography in patients resuscitated from out-of-hospital cardiac arrest-A systematic review and meta-analysis

IntroductionOut-of-hospital cardiac arrest has a poor prognosis. The main aetiology is ischaemic heart disease.AimTo make a systematic review addressing the question: “In patients with return of spontaneous circulation following out-of-hospital cardiac arrest, does acute coronary angiography with coronary intervention improve survival compared to conventional treatment?”MethodsPeer reviewed articles written in English with relevant prognostic data were included. Comparison studies on patients with and without acute coronary angiography were pooled in a meta-analysis.ResultsThirty-two non-randomised studies were included of which 22 were case-series without patients with conservative treatment. Seven studies with specific efforts to control confounding had statistical evidence to support the use of acute coronary angiography following resuscitation from out-of-hospital cardiac arrest. The remaining 25 studies were considered neutral. Following acute coronary angiography, the survival to hospital discharge, 30 days or six months ranged from 23% to 86%. In patients without an obvious non-cardiac aetiology, the prevalence of significant coronary artery disease ranged from 59% to 71%. Electrocardiographic findings were unreliable for identifying angiographic findings of acute coronary syndrome. Ten comparison studies demonstrated a pooled unadjusted odds ratio for survival of 2.78 (1.89; 4.10) favouring acute coronary angiography.ConclusionNo randomised studies exist on acute coronary angiography following out-of-hospital cardiac arrest. An increasing number of observational studies support feasibility and a possible survival benefit of an early invasive approach. In patients without an obvious non-cardiac aetiology, acute coronary angiography should be strongly considered irrespective of electrocardiographic findings due to a high prevalence of coronary artery disease.