Sudden cardiac arrest in patients with cancer in the general population: insights from the Paris-SDEC registry

Background Data on the management of patients with cancer presenting with sudden cardiac arrest (SCA) are scarce. We aimed to assess the characteristics and outcomes of SCA according to cancer history. Methods Prospective, population-based registry including every out-of-hospital SCA in adults in Paris and its suburbs, between 2011 and 2019, with a specific focus on patients with cancer. Results Out of 4069 patients who had SCA admitted alive in hospital, 207 (5.1%) had current or past medical history of cancer. Patients with cancer were older (69.2 vs 59.3 years old, p<0.001), more often women (37.2% vs 28.0%, p=0.006) with more frequent underlying cardiovascular disease (41.1% vs 32.5%, p=0.01). SCA happened more often with a non-shockable rhythm (62.6% vs 43.1%, p<0.001) with no significant difference regarding witness presence and cardiopulmonary resuscitation (CPR) performed. Cardiac causes were less frequent among patients with cancer (mostly acute coronary syndromes, 25.5% vs 46.8%, p<0.001) and had more respiratory causes (pulmonary embolism and hypoxaemia in 34.2% vs 10.8%, p<0.001). Still, no difference regarding in-hospital survival was found after SCA in patients with cancer versus other patients (26.2% vs 29.8%, respectively, p=0.27). Public location, CPR by witness and shockable rhythm were independent predictors of in-hospital survival after SCA in the cancer group. Conclusions One in 20 SCA occurs in patients with a history of cancer, yet with fewer cardiac causes than in patients who are cancer-free. Still, in-hospital outcomes remain similar even in patients with known cancer. Cancer history should therefore not compromise the initiation of resuscitation in the context of SCA.