Organ-specific biomarker analysis (Table 4)
Analysis of liver function biomarkers showed an AST count increase in
both groups, but significantly higher in MIVT, together with raised ALT
counts. In contrast, LDH levels increased significantly more in the
sternotomy group compared to MIVT group.
Renal function biomarkers increased similarly in both groups as shown in
Figure 5, corresponding with a decrease of GRF, but without reaching a
statistically significant difference.
Myocardial damage assessed by troponin I and creatine kinase(CK) and
creatine kinase MB(CK-MB) counts revealed no difference of postoperative
troponin levels between MIVT and sternotomy. However, CK counts
increased significantly more in the MIVT group than in the sternotomy
group (MIVT: 89.74 to 933.02 U/l vs. sternotomy: 73.92 to 89.74 U/l;
p=0.002). In contrast, CK-MB levels increased postoperatively in both
groups, albeit based on samplings of only 44 patients.
Non-specific systemic inflammation was considered by leukocyte counts
and C-reactive protein(CRP) levels. Leukocyte counts increased
significantly more in MIVT compared to sternotomy. However, CRP counts
raised significantly more from the first to second postoperative day in
the sternotomy compared to the MIVT group(p<0.001)(Figure 6).
Other hematologic biomarkers are listed in Table 4.
As red blood cell derivatives are confounded by intra- and postoperative
transfusion, only the latter parameters are analyzed. Mediastinal
drainage loss during the first 12 and 48 hours was higher in the MIVT
group. No significant difference was found in the number of blood
transfusions nor total blood transfusion volume.
The impact of the surgical approach on lung function was represented by
the length of mechanical ventilation. No difference between groups was
found concerning mechanical ventilation longer than 24 hours.