Table 3

Adverse clinical endpoints at hospital discharge and 6-month follow-up in patients with confirmed ST-elevation myocardial infarction

CharacteristicNo supplemental oxygen exposure
N=128
Low supplemental oxygen exposure
N=105
Moderate supplemental oxygen exposure
N=104
High supplemental oxygen exposure
N=104
p Value
At hospital discharge, n (%)
 All-cause mortality4 (3.1)4 (3.8)3 (2.9)3 (2.9)0.98
 Cardiac mortality3 (2.3)2 (1.9)3 (2.9)3 (2.9)0.96
 Recurrent myocardial infarction0 (0.0)1 (1.0)4 (3.8)9 (8.7)0.001
 Stroke or transient ischaemic attack0 (0.0)1 (1.0)2 (1.9)1 (1.0)0.50
 Cardiogenic shock6 (4.7)8 (7.6)10 (9.6)16 (15.4)0.04
 Coronary artery bypass grafting2 (1.6)7 (6.7)1 (1.0)4 (3.8)0.07
 Major bleeding2 (1.6)5 (4.8)0 (0.0)8 (7.7)0.01
 Arrhythmia30 (23.4)37 (35.2)42 (40.4)49 (47.1)0.002
 ST-segment resolution >70%*85 (70.2)72 (70.6)72 (71.3)52 (50.2)0.003
At 6-month follow-up, n (%)†
 All-cause mortality6 (4.7)5 (5.0)4 (4.0)6 (5.9)0.94
 Cardiac mortality5 (3.9)2 (2.0)3 (3.0)5 (4.9)0.70
 Recurrent myocardial infarction3 (2.4)3 (3.0)5 (5.0)13 (12.7)0.003
 Stroke or transient ischaemic attack1 (0.8)3 (3.0)3 (3.0)1 (1.0)0.45
 Coronary artery bypass grafting5 (3.9)9 (8.9)4 (4.0)7 (6.9)0.34
 Repeat revascularisation12 (9.4)7 (6.9)11 (11.0)9 (8.8)0.79
 Readmission26 (20.5)21 (20.8)26 (26.0)26 (25.5)0.66
 Major adverse cardiac event‡20 (15.7)17 (16.8)20 (19.8)23 (22.5)0.56
  • *Measured on ECG one day after hospital admission.

  • †14 of 441 were lost to follow-up.

  • ‡Major adverse cardiac event denotes any of the following: all-cause mortality, recurrent myocardial infarction, repeat revascularisation or stroke.