Clinical & Experimental Cardiology
Open Access

Abstract

Do Ionized Calcium and Phosphorus Levels have any Prognostic Value in Patients with ST-Segment Elevation Myocardial Infarction?

Hromadka M, Dragounova E, Bernat I, Seidlerova J, Ostadal P and Rokyta R

Introduction: The significance of serum calcium and phosphorus levels in patients with acute myocardial infarction is not entirely clear. Objective: To assess the potential predictive value of ionized calcium (iCa) and phosphorus levels in acute STsegment elevation myocardial infarction (STEMI) patients treated using primary percutaneous coronary intervention. Design and Methods: A total of 256 patients included in the STEMI-RADIAL study were evaluated. Calcium and phosphorus levels were measured on admission, and after 6 h and 12 h. Correlations of these values with other laboratory and clinical parameters were assessed. Results: Within the first 12 h of admission we observed a statistically significant increase in iCa and phosphorus levels; none of the patients received iCa or phosphorus supplementation. Hypocalcemia was present in 14% of patients at baseline and was associated with increased troponin I levels (P<0.0018). After adjustment for confounders, a higher left ventricular ejection fraction was associated with increased iCa levels after 12 h (P=0.010) and lower values of peak troponin I (P<0.0001) and C-reactive protein (CRP; P<0.006) levels. Baseline hypophosphatemia was associated with longer chest pain duration (P=0.044) and lower CRP levels after 24 h (P=0.040). The mortality rate of the group after one month and one year was 1.32% and 3.08%, respectively. Of the biochemical parameters studied, only the CRP level was associated with higher one-month mortality (odds ratio [OR] 4.01 [95% confidence interval (CI) 1.16 to 13.9]; P=0.029). Twelve-month mortality was associated with CRP level (OR 2.21 [95% CI 1.00 to 4.89]; P=0.049) and also patient age (OR 1.08 [95% CI 1.00 to 1.17]; P=0.045). Conclusion: We did not find any prognostic value with regard to baseline levels of ionized calcium and phosphorus. We observed an association between iCa levels 12 h after admission and left ventricular systolic dysfunction in STEMI patients. However, the clinical relevance of this finding is not yet clear. Patients with longer chest pain duration had lower baseline phosphorus levels.