RESUMEN
Background: The perioperative impact of calcium and vitamin D on left ventricular (LV) performance during major cardiac surgery remains unexplored. We aimed to assess the relation of calcium and vitamin D measured at different time points with the LV ejection fraction (EF), and to investigate whether changes in EF correlate with postoperative outcomes. Methods: We enrolled 83 patients, in whom ionized calcium was measured before, during, and after surgery (until discharge), vitamin D preoperatively, and EF pre- and postoperatively at 24 h. The postoperative outcomes were cardiopulmonary bypass (CPB) time, aortic cross-clamp time, mechanical ventilation time, vasoactive inotropic score (VIS) (intraoperative, day 0, day 1), and ICU stay time. Results: The mean age was 64.9 ± 8.5 years, with 21 of the patients (25%) having an EF < 50%. The median change from preoperative to postoperative EF was -2.0 (-10.0-0.0) % (p < 0.001). At the baseline, the EF < 50% group had significantly lower preoperative vitamin D levels than the EF ≥ 50% group (p = 0.048). The calcium trend did not differ across the groups. Preoperative EF was significantly associated with CPB time (r = 0.22, p = 0.044) and aortic cross-clamp time (r = 0.24, p = 0.031). Postoperative EF was significantly and inversely associated with intraoperative VIS (r = -0.28, p = 0.009), VIS day 0 (r = -0.25, p = 0.020), VIS day 1 (r = -0.23, p = 0.036), and ICU length of stay (r = -0.22, p = 0.047). Finally, the change in ejection fraction was significantly and inversely associated with CPB time (r = -0.23, p = 0.037), aortic cross-clamp time (r = -0.22, p = 0.044), intraoperative VIS (r = -0.42, p < 0.001), VIS day 0 (r = -0.25, p = 0.024), mechanical ventilation time (r = -0.22, p = 0.047), and ICU length of stay (r = -0.23, p = 0.039). Conclusions: The fluctuations in perioperative ionized calcium levels were not associated with the evolution of LVEF, although preoperative vitamin D levels may affect those with low EF. Correspondingly, a reduced EF significantly impacted all the studied postoperative outcomes. Further investigation into biomarkers affecting cardiac inotropic function is warranted to better understand their significance.
RESUMEN
Background: There is emerging but conflicting evidence regarding the association between calcium biomarkers, more specifically ionized calcium and the prognosis of intensive care unit (ICU) postoperative cardiac patients. Methods: Our study investigated the relationship between ionized calcium, vitamin D, and periprocedural clinical events such as cardiac, neurologic and renal complications, major bleeding, vasoactive-inotropic score (VIS), and length of ICU and hospitalization. Results: Our study included 83 consecutive subjects undergoing elective major cardiac surgery requiring cardiopulmonary bypass. The mean age of the participants was 64.9 ± 8.5 years. The majority of procedures comprised isolated CABG (N = 26, 31.3%), aortic valve procedures (N = 26, 31.3%), and mitral valve procedures (N = 12, 14.5%). A difference in calcium levels across all time points (p < 0.001) was observed, with preoperative calcium being directly associated with intraoperative VIS (r = 0.26, p = 0.016). On day 1, calcium levels were inversely associated with the duration of mechanical ventilation (r = -0.30, p = 0.007) and the length of hospital stay (r = -0.22, p = 0.049). At discharge, calcium was inversely associated with length of hospital stay (r = -0.22, p = 0.044). All calcium levels tended to be lower in those who died during the 1-year follow-up (p = 0.054). Preoperative vitamin D levels were significantly higher in those who experienced AKI during hospitalization (median 17.5, IQR 14.5-17.7, versus median 15.3, IQR 15.6-20.5, p = 0.048) Conclusion: Fluctuations in calcium levels and vitamin D may be associated with the clinical course of patients undergoing cardiac surgery. In our study, hypocalcemic patients exhibited a greater severity of illness, as evidenced by elevated VIS scores, and experienced prolonged mechanical ventilation time and hospital stays. Additional larger-scale studies are required to gain a deeper understanding of their impact on cardiac performance and the process of weaning from cardiopulmonary bypass, as well as to distinguish between causal and associative relationships.