Integrated area of desaturation index in patients with myocardial infarction

Our aim in this study was to estimate the effectiveness of the integrated area of desaturation (IAD) index as a measure of sleep-disordered breathing (SDB) severity. The study comprised 98 patients with 36 old myocardial infarction (OMI), 40 with acute myocardial infarction (AMI), and 22 without myocardial infarction as control normal subjects. The ejection fraction was significantly lower (OMI: 48.3 ± 14.6% vs. AMI: 56.0 ± 10.5% vs. Control: 67.1 ± 9.3%, p < 0.001) and brain natriuretic peptide (BNP) was significantly higher (OMI: 554 ± 816 pg/ml vs. AMI: 170 ± 298 pg/ml vs. Control: 43 ± 65 pg/ml, p < 0.001) in patients with OMI. The apnea-hypopnea index (AHI) did not show significant difference, but the IAD index was significantly greater in patients with OMI (OMI: 73.8 ± 49.0% s/min vs. AMI: 35.4 ± 21.5% s/min vs. Control: 46.8 ± 29.3% s/min, p < 0.0001). Patients with low ejection fraction and high BNP demonstrated great IAD index and hence, our results suggest the possibility of IAD index being more accurate in indicating the severity of SDB in patients with myocardial infarction.