Role of H-FABP values in determining the etiologic factors of the cardiac injuries

Introduction Cardiac injury resulting from blunt thoracic trauma is a frequent clinical occurrence which is difficult to diagnose. Our purpose in this study was to research whether H-FABP, which is a new marker for the diagnosis of cardiac injury, can be used in this patient group. Methods 50 patients with blunt thoracic injury who were admitted to our emergency service within a period of 8 months and 50 cases as controls were included in our study. Results Of the 50 patients with blunt thoracic injury in our study, 88% were male while 12% were female. The average age of the patients was 43 ± 15.15. While 27 (54%) of the 50 patients with blunt thoracic injury had cardiac injury, 23 (46%) did not have cardiac injury. The results of the statistical analyses showed a significant association between thorax trauma and cTnI, CPK, CPKMB and H-FABP (p<0.05). While there was a significant association between cardiac injury resulting from thoracic trauma and cTnI, ECG and TTE (p<0.05), there was no significant association between CPK, CPKMB and H-FABP (p>0.05). Conclusion In thoracic traumas, cardiac injury diagnosis can be made as a result of the assessment with Troponin-I, ECG and ECHO. For cardiac injury diagnosis, wide scale prospective studies are needed for H-FABP use.


Introduction
Today, traumas are one of the most important public health issues. About 1/3 of the patients hospitalized for traumas are severe thoracic traumas. Although the heart is thought to be well protected inside the thoracic cage, blunt cardiac injury occurs in 20 to 70% of motor vehicle accidents. Cardiac injury resulting from blunt thoracic trauma is a frequent clinical occurrence which is difficult to diagnose. Cardiac injuries can occur in a wide spectrum ranging from asymptomatic myocardial injury to rupture and death.
Generally, there may not be a correlation between the severity of the trauma and cardiac injury. There is no single golden standard test for diagnosis of cardiac injury [1]. Since heart-type fatty acid binding protein (H-FABP) diffuses to plasma rapidly following myocardial injury, it is a biochemical marker which has come to the forefront recently in the early diagnosis of cardiac injury [2]. Its concentration increases in the first 1.5 hours, reaches the peak point within 5-6 hours and tends to decrease after 6 hours. It returns to normal levels 24-30 hours later. It is thought to have an important place in the diagnosis of myocardial injury [3]. Apart from myocardium, it is found in skeleton muscle, brain, mammary gland and placenta. There are recent studies which state that it can be used in the early diagnosis of especially acute coronary syndrome, coronary failure, kidney and liver injury, pulmonary embolism and some poisonings [4]. In this study, our purpose was to asses H-FABP, a new marker for the cardiac injury diagnosis in patients with thoracic trauma by using cardiac troponin (cTnI), creatine phosphokinase (CPK), creatine phosphokinase myocardial band (CPKMB), transthoracic echocardiography (TTE) and electrocardiography (ECG). The "SPSS 15.0 for Windows" package program was used for the statistics used in the study. Chi-squre test was conducted for the comparison of the categorical data whereby those whose p value equaling 0.05 or less were considered to be positive values. Mann-Whitney test was employed in the correlation evaluation.

Results
Of the 50 patients with thoracic injury in our study, 44 (88%) were male while 6 (12%) were female.

Discussion
One of the most important and also most neglected injuries following a trauma is cardiac injury resulting from thoracic injury.
Although the mechanism of cardiac injury in blunt thoracic trauma is not completely understood, it is thought that it occurs as a result of heart being stuck between the vertebral colon and sternum or as a result of increased thoracic pressure being transmitted to cardiac cavities [5].  [9]. The results of our study were similar to the results in literature.
The incidence of cardiac injury resulting from blunt chest trauma in literature varies between 8% and 76% [10]. The incidence of cardiac injury was 50% in Skinner et al.'s study [9]. 54% cardiac injury was found in our study, which was in parallel with the literature.
The rate of positive finding in echo has been reported as 13-38% in literature [11]. In their study, Emet et [9]. It was stated that the rates were low since their study was retrospective.
In our study, ECG change was found in 40.7% of the patients with cardiac injury. Significant association was found between cardiac injury and ECG in our statistical analyses (p<0.05). It is difficult to find out cardiac injury with only one ECG. The fact that there is no ECG change although there is cardiac injury is an important finding.
In trauma patients, ECG may show nonspecific changes due to hypoxia, hypovolemia, anemia, failures in serum electrolytes, vagal or sympathic tonus. Previous ECG changes of the patients and ECG changes which are normal for the patients but accepted as positive findings increase insecurity to this parameter [12,13].
As we included increased Tn-I level within the diagnostic criteria for BCI, the specificity for Tn-I was 100%; however, its sensitivity was