A Comparative Study on the Diagnostic Utility of Creatine Kinase-MB (Myocardial Band) Mass Estimation Over Its Activity Measurement in Patients with Acute Myocardial Infarction in a Tertiary Care Hospital in Puducherry

Abstract

BACKGROUND Cardiovascular diseases (CVDs) are one of the major health problems and leading cause of death worldwide. Acute myocardial infarction (AMI) is one of the cardiovascular diseases which has high mortality in early hours of presentation and hence early and accurate diagnosis is important to reduce the morbidity and mortality. Troponin I and CKMB (Creatine Kinase-Myocardial Band) activity are the routine biomarkers used for early diagnosis of AMI. Since there is a high degree of instability in the measurement of CKMB activity and also there are frequent noncorrelation with the Troponin I levels, we aimed to estimate and compare the levels of CKMB mass and CKMB activity in patients with and without AMI. METHODS This comparative study included 40 cases and 40 controls. Cases were adult patients between the age group of 30 -70 years diagnosed with AMI by electrocardiogram (ECG) and positive troponin I, and controls were who presented with non myocardial infection (MI) chest pain. Blood samples were collected to estimate CKMB activity and CKMB mass. RESULTS The median value of CKMB activity in controls was 21 IU/L (IQR 13.25-27.75) and that in cases was 40 IU/L (IQR 30.25-94.25) and this difference is statistically significant. The median value of CKMB mass in controls was 5 ngmL (IQ 4-6) and that in cases was 19.50 ng/mL (IQR 6-61.50) which is also statistically significant in differentiating both. In Spearman correlation test, both showed a better statistical significance and correlation in cases (r = 0.787). It was evident that the median value of CKMB activity in controls was higher than that of the normal range for CKMB activity which is 8-16 IU/L, but the median value of CKMB mass in controls was well within the normal range of 5- 10 ng/mL, considering it to be a better marker for eliminating false positive results. CONCLUSIONS CKMB mass can be considered as a better marker than CKMB activity for accurate diagnosis of AMI along with troponin I. KEYWORDS Cardiovascular Diseases, Biomarker, Acute Myocardial Infarction, CKMB Mass, CKMB Activity

CK-MB Aktivite ve Kütle Ölçüm Yöntemlerinin Karşılaştırılması

“…Bland-Altman Grafiğine göre; hesaplanan değerler ile ölçülen değerlere ait farkların ortalaması 0.008 (-5.65 ile 5.67 arasında) ve standart sapması 17.7 olarak bulundu (Şekil 3). (18). Marwah ve ark.…”