The prevalence of heart failure (HF) among adult populations in developed countries is approximately 1–2% which increases to ≥10% in populations above 70 years of age. [1] Patients with HF have poorer prognosis in general, however the survival is improving with implementation of evidence-based drug and device therapy. [2,3] HF patients are specifically susceptible to sudden cardiac death and in those with severe symptomatic HF an implantable cardioverter-defibrillator (ICD) is typically indicated. [1,4] Patients with HF usually have several other co-morbid conditions which affect their quality of life. [5] Studies have reported differing opinions towards cardiopulmonary resuscitation (CPR) and do not resuscitate (DNR) decisions in patients with HF. [6,7] Naturally, the decision to DNR is associated with increased mortality in HF patients. [6]

The global 30-day and 1-year survival is poor after an out-of-hospital cardiac arrest (OHCA). [8] The knowledge on consequences of out-of-hospital cardiac arrest (OHCA) where resuscitation was attempted in patients with HF is lacking and such data are particularly relevant given the significantly improved outcomes in recent years along with substantial improvements in bystander cardiopulmonary resuscitation and public access to defibrillators. [[9], [10], [11], [12], [13], [14]] Thus, the aims of the current study are two-fold: 1) compare the clinical outcomes among the patients with and without preexisting HF after OHCA where a resuscitation attempt was initiated in the prehospital setting and 2) to identify the clinical variables associated with poor prognosis after OHCA in patients with pre-existing HF.