We investigated the relation of initial metabolic acidemia to in-hospital mortality in patients treated with emergency coronary angioplasty for shock complicating first anterior ST-segment elevation myocardial infarction (STEMI).
Methods
A total of 23 consecutive patients (17 men, 73±12 years) with Killip class IV class due to anterior STEMI were studied. Using median levels of arterial base excess (BE, −5.8 mmol/L), the patients were divided into high and low BE groups, and both groups were compared regarding microvascular revascularization and clinical outcomes. To evaluate myocardial tissue-level reperfusion, severe microvascular injury was defined by the presence of both angiographic myocardial blush grade 0/1 and less than 30 % resolution of ST-elevation after angioplasty.
Results
In-hospital mortality was 92 % in the high BE group (−12.0±4.9 mmol/L) as compared with 9 % in the low BE group (−0.9±2.4mmol/L, p=0.0001 vs. high BE group). Baseline clinical and angiographic characteristics were not different between the two groups. Arterial gas analysis showed lower pH and higher levels of lactate in the high BE group than in the low BE group (7.22±0.16 vs. 7.42±0.06, p=0.006, 8.52±4.43 vs. 2.42±1.33, p=0.016). Despite successfully culprit angioplasty in all cases, the incidence of severe microvascular injury was significantly high in the high BE group as compared with the low BE group (83 vs. 36 %, p=0.018). Initial levels of BE showed a significant negative relation to ST-segment resolution (r=0.61, p=0.002). A multivariate regression analysis demonstrated a potent association of initial levels of BE with severe microvascular injury (r
2
=0.341, p=0.015).
Conclusions
We identified the pivotal association of initial metabolic crisis with severe microvascular reperfusion injury leading to high in-hospital mortality in patients with cardiogenic shock complicating STEMI.
Epidemiology of cardiogenic shock and cardiac arrest complicating non‐ST‐segment elevation myocardial infarction: 18‐year US study
