[BLITZ-AF Cancer study: an international observational research project on patients with atrial fibrillation and cancer].

Background: Cancer is an important condition associated with the development of atrial fibrillation (AF). The objectives of the BLITZ-AF Cancer study were to collect real-life information on the clinical profile and use of antithrombotic drugs in patients with AF and cancer to improve clinical management, as well as the evaluation of the association between different antithrombotic treatments (or their absence) and the main clinical events.

Methods: European multinational, multicenter, prospective, non-interventional study conducted in patients with AF (electrocardiographically confirmed) and cancer occurring within 3 years. The CHA2DS2-VASc and the HAS-BLED scores were calculated in all enrolled patients.

Results: From June 2019 to July 2021, 1514 patients were enrolled, 36.5% women, from 112 cardiology departments in 6 European countries (Italy, Belgium, the Netherlands, Spain, Portugal and Ireland). Italy enrolled 971 patients in 77 centers. Average age of patients was 74 ± 9 years, of which 20.9% affected by heart failure, 18.1% by ischemic heart disease, 9.8% by peripheral arterial disease and 38.5% by valvular diseases; 41.5% of patients had a CHA2DS2-VASc score ≥4. The most represented cancer sites were lung (14.9%), colorectal tract (14.1%), prostate (8.8%), or non-Hodgkin's lymphoma (8.1%). Before enrollment, 16.6% of patients were not taking antithrombotic therapy, while 22.7% were on therapy with antiplatelet agents and/or low molecular weight heparin. After enrollment these percentages decreased to 7.7% and 16.6%, respectively and, at the same time, the percentage of patients on direct oral anticoagulant (DOAC) therapy increased from 48.4% to 68.4%, also to the detriment of those on vitamin K antagonist therapy.

Conclusions: The BLITZ-AF Cancer study, which enrolled patients diagnosed with AF and cancer, highlights that the use of DOACs by cardiologists in this clinical context has increased, even though the guidelines on AF do not give accurate indications about oral anticoagulant therapy in patients with cancer.