Prognostic value of acid-base balance parameters obtained from peripheral venous blood sample on admission in patients with myocardial infarction treated with percutaneous coronary intervention

Abstract

Peripheral venous blood sample may be used to obtain acid‑ base balance parameters (PVA‑BP) measured in rapid point‑of‑care test (POCT) analyzers on admission to an emergency department (ED). Thus, lactates, anion gap (AG), and base excess (BE) may be early prognostic markers in patients with myocardial infarction (MI). We aimed to confirm the relationship between PVA‑BP on admission and the outcome in patients with MI treated with percutaneous coronary intervention (PCI). This was a retrospective, observational analysis of MI patients admitted primarily to an ED and secondly transferred to PCI department. A total of 336 patients (41.1% ST‑elevated MI, 58.9% non-ST‑elevated MI) were divided according to their lactate level, that is, G1 group with lactate below or equal to 2.0 mmol/l (n = 207) and G2 group with lactate above >2.0 mmol/l (n = 129). G2 patients had higher values of AG (mean, [SD], 9.6 [4.3] vs 6.8 [3.2] mEq/l; P <0.001) and lower BE (median [interquartile range], -0.7 [-3.9 to 0.8] vs 1.0 [-0.2 to 2.4] mEq/l; P <0.001). In‑hospital nonsurvivors had higher values of lactates (4.0 [2.0-8.7] vs 1.7 [1.3-2.4] mmol/l; P <0.001), AG (10.5 [4.6] vs 7.7 [3.8] mEq/l; P <0.001), and lower BE (-4.8 [-10.6 to -1.8] vs 1.5 [-0.8 to 2.3] mEq/l; P <0.001) than the survivors. Lactates, AG, and BE correlated with Global Registry of Acute Coronary Events score (r = 0.361, P <0.001; r = 0.158, P = 0.004; r = -0.383, P <0.001, respectively). Only BE independently predicted both 30- and 365‑day mortality in the whole group (hazard ratio [HR], 0.79; 95% CI, 0.65-0.95; P = 0.01 and HR, 0.89; 95% CI, 0.76-0.99; P = 0.04, respectively) as well as in‑hospital mortality among patients without infarct‑related out‑of‑hospital cardiac arrest (odds ratio, 0.74; 95% CI, 0.57-0.97; P = 0.03). In the patients admitted to the ED with MI treated with PCI the evaluation of PVA‑BP in POCT analyzers may be a reliable tool for early risk stratification.