4. DISCUSSION
In a study, it was stated that the serum prolidase (U/L) level increased when patients with CAD were compared with control cases. In the same study, serum prolidase (U/L) levels gave a statistically significant result with Gensin Score. Since coronary atherosclerosis is a complex multifactorial disease, it has been stated that it may play an important key role in serum prolidase (U/L) level in patients with CAD with the progression of atheroscleratic plaque. 22 These data may show that the changes in serum prolidase (U/L) levels in the Bypass Entry and Bypass outlet blood of the patients in group 1 in our study may be caused by surgical trauma, cross clamp duration, cardiopulmonary bypass technique and extracorporeal circulation and respiratory support.
Patients with ischemic mitral regurgitation exhibit different pathology and clinical findings compared to mitral regurgitation due to other etiologies, and also present with a higher risk of mortality, morbidity, and poor prognosis.23
In a study, it was shown that vascular tissues lose tissue compatibility with advancing age. In the study, it was stated that there was a similar change between serum prolidase (U/L) activity and age. In this study, it was proven that increased prolidase activity is not only associated with aging and female gender, but also with the presence and duration of hypertension. It is requested to draw attention to its importance in the evaluation of prolidase activity in patients with hypertension. To the best of our knowledge, this is the first study to show that hypertension is associated with increased serum prolidase (U/L) activity. As a result of this study, it has been shown that there is a significant increase in serum prolidase (U/L) activity in patients with hypertension.24
In a study, they conducted a study on aortic stiffness related to blood and aortic tissue prolidase activity and immunohistochemical expression of prolidase in aortic tissue. Previous studies have shown that serum prolidase (U/L) activity is increased in patients with coronary artery disease (CAD) and hypertension. However, this correlation was thought to be related to prolidase secretion from other organs or drug use. They reported that this study is the first to evaluate the correlation of aortic stiffness with tissue prolidase activity and immunohistochemical expression of prolidase in aortic tissue. They found that plasma prolidase activity was higher in the study group than in the control group, as in previous studies. In addition, patients with pulmonary arterial pressure, diabetes mellitus (DM), dyslipidemia, tobacco use, myocardial infarction and chronic obstructive pulmonary disease (COPD) were reported to be in the majority in the study. Previous studies have shown that aortic stiffness is higher in CAD patients, blood prolidase activity is higher in DM and dyslipidemia patients, and lower in COPD patients.25
In the study named serum prolidase (U/L) activity in degenerative and rheumatic heart patients; The patient group who had valve replacement due to rheumatic etiology was compared with a group of patients who had valve replacement due to degenerative etiology and a group of healthy volunteers. They measured prolidase activity in all groups. Their conclusion was that prolidase activity was significantly higher in the control group than in the patient groups. However, there was no statistically significant difference between the patient groups in terms of serum prolidase (U/L) activity. No correlation was found between serum prolidase (U/L) activity and valve disease. In the light of these findings, they concluded that rheumatic and degenerative heart disease is associated with decreased serum prolidase (U/L) activity.26 In our study; There was an increase in prolidase level in group 2 bypass access and group 1 bypass access blood, but it did not show a significant result. Prolidase level in group 2 bypass outlet and group 1 bypass outlet blood increased, but it did not show a significant result.
In another study, in the evaluation of serum prolidase (U/L) activity in the patient group with coronary artery disease; stated that serum prolidase (U/L) level increased significantly. They stated that serum prolidase (U/L) levels were significant, but prolidase levels decreased in the control groups when compared with coronary artery disease.27 In our study, there was an increase in the level of prolidase in the blood of group 2 patients, but it did not give statistically significant results in our study.
When we look at the serum prolidase (U/L) levels in the blood of the group 2 patients entering the surgery (1084.07 ± 260.09 U/L) and exiting the surgery (1337.74 ± 397.61 U/L), this result gave us a statistically significant difference. (p < 0.05). When the serum prolidase (U/L) levels in the blood of the patients in Group 1 at the time of entry to the operation (1038.28 ± 150.09 U/L) and after the operation (1289.43 ± 357.34 U/L) were examined, the serum prolidase (U/L) levels increased significantly, making the study result statistically significant (p < 0.01). ). There was not much difference in serum prolidase (U/L) levels in the blood entering the surgery of the patients in group 2 and the patients in group 1 in the blood entering the surgery. When the serum prolidase (U/L) levels in the postoperative blood of the study group patients and the postoperative blood of the control group patients were evaluated, the serum prolidase (U/L) level increased in both patient groups compared to the access blood. However, despite the increase in the output blood levels of both groups, this serum prolidase (U/L) level increased at a more serious level in the study group patients who underwent ischemic mitral regurgitation in addition to bypass surgery. We have seen that patients who develop ischemic mitral regurgitation and additionally performing cardiac surgery cause a significant increase in serum prolidase (U/L) levels. The main reason for this increase was that the patient had primarily cardiac surgery and increased prolidase level due to this trauma (Figure 1).
A statistically significant difference was observed between serum prolidase (U/L) levels in group 2 bypass blood and group 2 bypass blood (p < 0.05) (Table 1). There is a significant difference between serum prolidase (U/L) levels in group 1 bypass blood and group 1 bypass blood (p < 0.01) (Table 2). There was no statistically significant difference between serum prolidase (U/L) levels in group 2 bypass blood and group 1 bypass blood (P = 0.686) (Table 3). There was no statistically significant difference between serum prolidase (U/L) levels in group 2 bypass blood and group 1 bypass blood (P = 0.463) (Table 4).
In our study, it was observed that the serum prolidase (U/L) level of the patients in group 2 was at a certain level at the entrance to the bypass, while it increased at the exit of the bypass. While the serum prolidase (U/L) level of the patients in Group 1 was at a certain level at the entrance to the bypass, it increased at the exit of the bypass. When we evaluated the serum prolidase (U/L) level of patients in group 2 and patients in group 1, there was no statistically significant difference between the two groups, although there was an increase in serum prolidase (U/L) values ​​in both groups. The prolidase level increased statistically significantly in both groups, but the serum prolidase (U/L) level in the blood of the patients in group 2 was higher than the serum prolidase (U/L) level in the blood of the patients in group 1.