Serum Creatinine Phosphokinase In Acute Myocardial Infarction

Abstract

CREATINE phosphokinase (CPK) is an enzyme abundantly present in skeletal and cardiac muscle cells. It catalyzes the phosphorylation of muscle creatine, a reversible reaction requiring adenosine triphosphate (ATP): In 1959 Ebashi et al first utilized the measurement of this enzyme as a diagnostic aid.¹They determined the serum creatine phosphokinase (SCPK) in patients with muscular disorders and found abnormal elevations in a large percentage of patients with progressive muscular dystrophy of the Duchenne type. Other investigators have since confirmed these findings^2-4and in addition have enlarged the diagnostic possibilities by finding abnormally high SCPK values in other disorders affecting muscle tissue, such as dermatomyositis^3,4hypothyroidism,⁵following cardiac surgery,⁶and during acute myocardial infarction.^7-10 Since CPK is so heavily concentrated in muscle, as opposed to other tissues,¹¹it possesses a potentially high degree of diagnostic specificity, in contradistinction to the ubiquitous transaminases and dehydrogenases. Therefore, it is surprising that