Systolic blood pressure at admission, clinical manifestations, and in-hospital outcomes in patients with acute myocardial infarction

Background: Several clinical studies have demonstrated an inverse relationship between systolic blood pressure (SBP) at admission and in-hospital mortality in patients hospitalized for acute myocardial infarction (AMI). However, data on the relation between admission SBP and in-hospital prognosis in AMI patients are still lacking in Japan.

Methods and results: A total of 1211 AMI patients were classified into quintiles based on SBP at hospital admission (<106 mmHg, n = 241; 106-125 mmHg, n = 239; 126-140 mmHg, n = 244; 141-159 mmHg, n = 238; and ≥ 160 mmHg, n = 249). The patients with SBP < 106 mmHg tended to have higher age, Killip class ≥ 3 at admission, right coronary artery, left main trunk, or multivessels as culprit lesions, larger number of diseased vessels, lower Thrombolysis In Myocardial Infarction grade in the infarct-related artery before primary percutaneous coronary intervention (PCI), and higher value of peak creatine phosphokinase concentration. Patients with SBP <106 mmHg had a significantly higher mortality, while mortality was not significantly different among the other quintiles: 25.7% (<106 mmHg), 5.4% (106-125 mmHg), 5.7% (126-140 mmHg), 2.5% (141-159 mmHg), and 5.6% (≥ 160 mmHg) (p<0.001). On multivariate analysis, Killip class ≥ 3 at admission, admission SBP <106 mmHg, and age were the independent positive predictors of in-hospital mortality, whereas admission SBP 141-159 mmHg and primary PCI were the negative ones, but admission SBP 106-125 mmHg, admission SBP 126-140 mmHg, and admission SBP ≥ 160 mmHg were not.

Conclusions: These results suggest that admission SBP 141-159 mmHg might be correlated with better in-hospital prognosis, whereas admission SBP <106 mmHg was associated with in-hospital death in Japanese patients hospitalized for AMI.