No abstract

Background: 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. Methods: 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. Results: 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. Conclusions: 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. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01787110.

Background: The value of family history of coronary artery disease (CAD) in diagnosing acute coronary syndrome (ACS) in chest pain patients is uncertain, especially in relation to high-sensitivity assays for cardiac troponin T (hs-cTnT), which have improved ACS diagnostics. Our objective was to investigate the association between verified family history of CAD and ACS in chest pain patients, overall and in different strata of initial hs-cTnT. Methods: Data on chest pain patients visiting four emergency departments in Sweden during 2013–2016 were cross-referenced with national registers of kinship, diseases and prescriptions. Family history of early CAD was defined as the occurrence of myocardial infarction or coronary revascularization before the age of 55 years in male and 65 years in female first-degree relatives. The outcome was combined including ACS and cardiovascular death within 30 days of presentation. Results: Of 28,188 patients, 4.7% of patients had ACS. In total, 8.2% and 32.4% had a family history of early and ever-occurring CAD, respectively. Family history of CAD was positively associated with the outcome, independently of age, gender, cardiovascular risk factors and electrocardiogram findings. The strongest association was observed for family history of early CAD (odds ratio 1.62, 95% confidence interval 1.35–1.94). Stronger associations were observed in young patients (e.g. <65 years) and in patients with non-elevated initial hs-cTnT levels ( p-value for interaction = 0.004 and 0.001, respectively). Conclusions: Family history of CAD is associated with ACS in chest pain patients, especially in patients of young age or with non-elevated initial hs-cTnT levels.