Should creatine kinase-MB index be eliminated in patients with indeterminate troponins in the ED?

Acute Coronary Syndrome After Aneurysmal Subarachnoid Hemorrhage: Incidence, Risk Factors and Impact on the Outcome

Background and Objectives: Development of acute coronary syndrome (ACS) after aneurysmal subarachnoid hemorrhage (aSAH) strongly affects further neuro-intensive care management. We aimed to analyze the incidence, risk factors and clinical impact of ACS in aSAH patients. Materials and Methods: This retrospective analysis included 855 aSAH cases treated between 01/2003 and 06/2016. The occurrence of ACS during 3 weeks of aSAH was documented. Patients' demographic, clinical, radiographic and laboratory characteristics at admission were collected as potential ACS predictors. The association between ACS and the aSAH outcome was analyzed as the occurrence of cerebral infarcts in the computed tomography scans and unfavorable outcome (modified Rankin scale > 3) at 6 months after aSAH. Univariable and multivariable analyses were performed. Results: ACS was documented in 28 cases (3.3%) in the final cohort (mean age: 54.9 years; 67.8% females). In the multivariable analysis, there was a significant association between ACS, an unfavorable outcome (adjusted odds ratio [aOR] = 3.43, p = 0.027) and a borderline significance with cerebral infarcts (aOR = 2.5, p = 0.066). The final prediction model for ACS occurrence included five independent predictors (age > 55 years [1 point], serum sodium < 142 mmol/L [3 points], blood sugar ≥ 170 mg/dL [2 points], serum creatine kinase ≥ 255 U/L [3 points] and gamma-glutamyl transferase ≥ 36 U/L [1 point]) and showed high diagnostic accuracy for ACS prediction (AUC = 0.879). Depending on the cumulative score value, the risk of ACS in the cohort varied between 0% (0 points) and 66.7% (10 points). Conclusions: ACS is a rare, but clinically very relevant, complication of aSAH. The development of ACS can reliably be predicted by the presented prediction model, which enables the early identification of aSAH individuals at high risk for ACS. External validation of the prediction model is mandatory.

Changes in cardiac biomarkers in goats naturally affected by pregnancy toxemia

Pregnancy toxemia (PT) is considered one of the most common metabolic diseases with high impact on the production of small ruminants. The objective of this study was investigate possible myocardial damage in goats affected with PT by the determination of serum myocardial biomarkers CK-MB and cTnI. A total of 44 goats affected with PT, and 10 apparently healthy goats (control group or CG) were used in the study. In goats with PT, the serum concentrations of cTnI (0.43 ng/mL) were significantly higher than that in CG goats (0.06 ng/mL). Although CK-MB showed no significant difference, it was approximately three times higher in animals with PT. The serum concentrations of insulin were significantly lower in PT goats (5.03 ppmol/L) compared to CG goats (10.66 pmol/L). The serum concentrations of cortisol in PT goats (155.41 nmol/L) were significantly higher than that in CG goats (36.58 nmol/L). Results of this study indicate that a clinically significant myocardial damage might occur in goats affected with PT leading to significant elevations in values of cTnI and CK-MB. Therefore, these parameters could be used as a potential prognostic indicator in goats affected with this important disease.

Routine creatine kinase testing does not provide clinical utility in the emergency department for diagnosis of acute coronary syndromes

BACKGROUND

Despite the high sensitivity and negative predictive value of contemporary high-sensitivity troponin T assays (hsTnT), creatine kinase (CK) continues to be routinely tested for the diagnosis of acute coronary syndrome (ACS). We conducted a study to identify the clinical utility of routine CK measurement, its relevance in clinical decision making in the era of hsTnT, and the potential cost-savings achievable by limiting its use.

METHODS

We conducted a retrospective review of all adult patients presenting to a tertiary care center in the year 2017. We identified patients presenting with cardiac complaints who had non-diagnostic hsTnT and positive CK. These patients underwent chart review to determine whether a diagnosis of AMI was made.

RESULTS

A total of 36,251 presentations were reviewed. 9951 had cardiac complaints and 8150 had CK measured. 82% of these patients had hsTnT and CK measured; 2012 of these patients had non-diagnostic hsTnT with positive CK. Of these 2012 patients, only 1 was subsequently diagnosed with AMI (0.012%). CK provided no diagnostic benefit over hsTnT alone in > 99.9% of cases. With a cost for CK of $4/test, we estimated that routine CK testing costs at least $32,000 per year in our center, and over $100,000 per year across the region.

CONCLUSION

Routine CK testing does not provide a significant benefit to patient care and therefore represents an unnecessary system cost. Routine CK testing for the diagnosis of AMI should be eliminated from emergency departments in the era of hsTnT assays.

Effect of racing on the serum concentrations of cardiac troponin I and creatine kinase myocardial band in racing camels (Camelus dromedarius)

This study was designed to investigate the effect of racing on the serum concentrations of cardiac troponin I (cTnI) and creatine kinase myocardial (CK-MB) in healthy racing camels (Camelus dromedarius). Twenty-three racing camels scheduled for a 5 km race were investigated in this study. From each camel, 3 blood samples were collected: 24 h before racing (T0), within 2 h after the race (T1) and 24 h post-race (T2). Following the 5 km race, 91.3 % of the racing camels had increases in serum cTnI concentrations, while concentrations remained unchanged in 8.7 %. The cTnI concentration (median 0.06 ng/mL; range, 0.03-0.15 ng/mL) was significantly higher (P < 0.001) than the pre-race values (median 0.04 ng/mL; range, 0.01-0.07 ng/mL). Twenty-four hours post-race, the cTnI concentrations had returned very nearly to their pre-race values (median 0.04 ng/mL; range, 0.00-0.09 ng/mL) and were not significantly different (P = 0.35) from the pre-race values. Following the 5 km race, increases in CK-MB mass were seen in 17.4 % of the camels, with no changes in 4.3 % and decreases in 78.3 %. The CK-MB mass (median 0.41 ng/mL; range, 0.19-0.60 ng/mL) did not differ significantly (P = 0.84) when compared to the pre-race values (median 0.42 ng/mL; range, 0.32-0.55 ng/mL). Twenty-four hours post-race, the CK-MB mass concentrations (median 0.41 ng/mL; range, 0.15-0.55 ng/mL) did not differ significantly (P > 0.05) compared to pre-race or immediate post-race values. Resting cTnI concentrations in the racing camels were initially low, but increased above the baseline level in most of the camels immediately after racing, and returned to pre-race values within the 24-h post-race period. CK-MB is a less sensitive biomarker for myocardial activity as compared with cTnI. These findings could be of importance when evaluating racing camels with suspected cardiac disease after recent hard exercise.

The cardiac biomarkers troponin I and CK-MB in nonpregnant and pregnant goats, goats with normal birth, goats with prolonged birth, and goats with pregnancy toxemia

This study was designed to establish the reference range for the cardiac biomarkers cardiac troponin I (cTnI) and creatine kinase myocardial band (CK-MB) in nonpregnant and pregnant goats, goats with normal birth, goats with prolonged birth associated with dystocia, and goats with pregnancy toxemia. Fifty-seven does, categorized into three groups (G1 to G3), were used. These groups were comprised of 20 healthy does (G1), 19 does with prolonged birth (G2), and 18 does with pregnancy toxemia (G3). Six blood samples (T0 to T5) were collected from G1. The first blood sample (T0) was taken before insemination, the second (T1) at the first trimester, the third (T2) at the second trimester, the fourth (T3) at the last trimester, the fifth (T4) within 12 h of parturition, and the sixth blood sample (T5) was taken 10 days after parturition. A sample of blood was obtained from G2 and G3 upon admission to the hospital. At T0 to T3, no cTnI was detected in any of the 20 does in G1. At parturition (T4), seven of the 20 goats (35%) exhibited slightly elevated cTnI concentrations (range, 0.01 to 0.04 ng/mL). Ten days after parturition (T5), cTnI was not detected in any of the 20 goats. In 10 of the 19 goats (53%) with prolonged birth (G2), the cTnI was significantly elevated to a mean value of 0.094 ± 0.155 ng/mL, with a maximum value of 0.61 ng/mL. In 16 of the 18 goats (89%) with pregnancy toxemia (G3), the cTnI was significantly elevated to a value of 0.852 ± 1.472 ng/mL, with a maximum value of 5.219 ng/mL. Comparing the values of CK-MB in G1 (T0 to T5), G2 and G3 revealed nonsignificant differences. Only a slight elevation in the CK-MB levels in goats with prolonged birth (G2) was noted. We concluded that in healthy does, the cardiac biomarker cTnI is not elevated during normal pregnancy. The serum cTnI concentration may be elevated in a number of goats at normal vaginal or cesarean delivery. Finally, cTnI is significantly elevated in does with pregnancy toxemia and could be used as a prognostic indicator in such cases. The cardiac biomarker CK-MB is not a good indicator of parturition stress in does. Serum cTnI is elevated in goats with pregnancy toxemia, indicating some degree of cardiac dysfunction.