Long-Term Effects of Oxygen Therapy on Death or Hospitalization for Heart Failure in Patients With Suspected Acute Myocardial Infarction
Authors: Tomas Jernberg, Bertil Lindahl, Joakim Alfredsson, Ellinor Berglund, Olle Bergström, Anders Engström, David Erlinge, Johan Herlitz, Raluca Jumatate, Thomas Kellerth, Jörg Lauermann, Krister Lindmark, Markus Lingman, Lina Ljung, Carina Nilsson, Elmir Omerovic, John Pernow, Annica Ravn-Fischer, David Sparv, Troels Yndigegn, Ollie Östlund, Stefan K. James, Robin Hofmann, Rickard Linder, Mattias Ekström, Lena Forsman, Oskar Angerås, Björn Hornestam, Robert Kastberg, Espen Haugen, Anna Millbourn, Jörg Carlsson, Urban Haaga, Linda Mellbin, Dinos Verouhis, Fredrik Kjellberg, Lennart Malmqvist, Gull-Britt Eriksson, Lennart Nilsson, Eva Swahn, Dimitrios Venetsanos, Tommy Pettersson, Melvin Pourbazargan, Martin Serrander, Jan-Erik Karlsson, Neshro Barmano, Martin Risenfors, Magnus Peterson, Ylwa Wallström, Ulf Ekelund, Marianne Erlandsson, Nils Witt, Mats Frick, Leif Svensson, Gabriel Arefalk, Bo Lagerqvist, Christofer Digerfeldt, Björn Byström
Journal: Circulation (2018)

In the DETO2X-AMI trial (Determination of the Role of Oxygen in Suspected Acute Myocardial Infarction), we compared supplemental oxygen with ambient air in normoxemic patients presenting with suspected myocardial infarction and found no significant survival benefit at 1 year. However, important secondary end points were not yet available. We now report the prespecified secondary end points cardiovascular death and the composite of all-cause death and hospitalization for heart failure.In this pragmatic, registry-based randomized clinical trial, we used a nationwide quality registry for coronary care for trial procedures and evaluated end points through the Swedish population registry (mortality), the Swedish inpatient registry (heart failure), and cause of death registry (cardiovascular death). Patients with suspected acute myocardial infarction and oxygen saturation of ≥90% were randomly assigned to receive either supplemental oxygen at 6 L/min for 6 to 12 hours delivered by open face mask or ambient air.A total of 6629 patients were enrolled. Acute heart failure treatment, left ventricular systolic function assessed by echocardiography, and infarct size measured by high-sensitive cardiac troponin T were similar in the 2 groups during the hospitalization period. All-cause death or hospitalization for heart failure within 1 year after randomization occurred in 8.0% of patients assigned to oxygen and in 7.9% of patients assigned to ambient air (hazard ratio, 0.99; 95% CI, 0.84–1.18; P=0.92). During long-term follow-up (median [range], 2.1 [1.0–3.7] years), the composite end point occurred in 11.2% of patients assigned to oxygen and in 10.8% of patients assigned to ambient air (hazard ratio, 1.02; 95% CI, 0.88–1.17; P=0.84), and cardiovascular death occurred in 5.2% of patients assigned to oxygen and in 4.8% assigned to ambient air (hazard ratio, 1.07; 95% CI, 0.87–1.33; P=0.52). The results were consistent across all predefined subgroups.Routine use of supplemental oxygen in normoxemic patients with suspected myocardial infarction was not found to reduce the composite of all-cause mortality and hospitalization for heart failure, or cardiovascular death within 1 year or during long-term follow-up.URL: https://www.clinicaltrials.gov. Unique identifier: NCT01787110.