Diagnosis of myocardial contusion

From July 1988 to July 1990, 159 consecutive cases of major blunt chest injury were evaluated prospectively for myocardial contusion with serial electrocardiographic monitoring, cardiac isoenzyme studies, and two-dimensional echocardiography. One hundred and forty-seven cases in the series were assessable; 97 of the patients were male, and 50 were female. They ranged in age from 2 to 97 years (average, 38.5 years). There were five deaths, none of cardiac origin. Total lactate dehydrogenase (LDH) values were elevated in 115 patients (78%); total creatine phosphokinase (CPK) values were elevated in 100 (68%). Cardiac isoenzyme patterns were consistent with myocardial contusion in 18 patients (12%). Seventy-five patients had abnormal electrocardiograms, and 10 of these had ectopic rhythms. Two-dimensional echocardiograms were completed in 58 cases; 12 of these (21%) were abnormal. Nineteen patients (25%) with abnormal rhythms had elevated LDH values, and 26 (35%) had elevated CPK values. One patient (10%) with ectopy had an abnormal echocardiogram. Two patients (11%) with abnormal isoenzyme patterns experienced dysrhythmias. Costs for hospitalization and studies amounted to $1,886 per patient. Given the poor predictive value of laboratory testing in patients with significant (ie, symptomatic) cardiac contusion, observation alone with electrocardiographic monitoring and treatment of symptomatic dysrhythmias is an adequate and cost-conscious treatment.