Predictors of Survival and Favourable Functional Outcomes Following an Out of Hospital Cardiac Arrest in Patients Systematically Brought to a Dedicated Heart Attack Centre

BACKGROUND: Despite advances in cardiopulmonary resuscitation, survival remains low after out of hospital cardiac arrest (OOHCA), with less than 20% of patients surviving to hospital discharge. Acute coronary ischaemia is the predominating cause and prompt delivery of patients to dedicated facilities may improve outcomes. Since 2011, all patients in London with OOHCA, in whom a cardiac aetiology is suspected, are brought to dedicated Heart Attack Centres (HACs). OBJECTIVES: We sought to determine the predictors for survival and favourable functional outcomes following OOHCA in this setting. METHODS: We analysed 182 consecutive OOHCA patients brought by the emergency services to Harefield Hospital - a designated HAC in London. Of these, 174 patients achieved return of spontaneous circulation. We analysed (a) all-cause mortality at 1 year; and (b) functional status at discharge using a modified Rankins score (mRS:0-6, where mRS0-3=favourable functional status). We used multivariate models to determine predictors of survival and favourable functional status. RESULTS: The overall survival rates were 66.7% at 30 days and 62.1% at 1 year. Of the 174 patients, 95 patients (54.5%) had favourable functional status at discharge. Patients with favourable functional status had significantly reduced mortality rates compared to those with poor functional status: 30 days (1.2% vs. 72.2%, p<0.001) and 1 year (5.3% vs. 77.2%, p<0.001). Multivariate analyses identified a shorter duration of resuscitation and absence of cardiogenic shock as consistent independent predictors of both favourable functional status and long-term survival (figure). CONCLUSIONS: The strategic delivery of OOHCA patients to HACs is associated with improved functional status and survival. Those with favourable functional status at discharge have significantly improved survival. Our study supports the standardisation of care for such patients with the widespread adoption of dedicated facilities.