Cryoprostatectomy consistently elevates serum creatine kinase-MB isoenzyme

To measure serum CK-MB, a market of myocardial infarction (MI), in elderly men before and after cryoprostatectomy.

Serum CK-MB was measured on each patient before and after cryoprostatectomy. Each patient's preoperative result was used as control measurement for comparison with measurements made after cryoprostatectomy.

Inpatient operating room and postanesthetic recovery unit of a university-affiliated general hospital.

38 male patients, mean (SEM) age 69.1 +/- 1.4 years, undergoing cryoprostatectomy.

All patients had a 12-lead ECG prior to surgery, in the recovery room, and 24 hours after surgery. Serum CK-MB was measured prior to induction of anesthesia, on arrival in the recovery room, and at 8 and 24 hours after surgery. Lactate dehydrogenase (LDH) and isoenzymes also were measured in 10 patients before and after cryoprostatectomy.

All patients underwent uneventful cryoprostatectomy. No patients had new ECG changes after surgery. All patients had normal serum CK and CK-MB concentrations before surgery. Serum CK and CK-MB were significantly elevated after cryoprostatectomy (p < 0.001). Enzyme values were greatest 8 hours after surgery: total CK mean 1453 +/- 145 U/L (range 199 to 3,356 U/L); CK-MB mean 52 +/- 3 ng/ml (range 12 to 114 ng/ml) or 5.0 +/- 0.5% of total CK (range 1.6% to 12.4%). All patients had significant elevations of LDH after cryoprostatectomy but did not show an increase in the ratio of LDH1 to LDH2 isoenzymes. Finally, unlike patients with an acute MI, the activity of CK-MB isoenzyme when measured by gel electrophoresis was two to three times greater (mean, 2.6 +/- 0.7) than the concentration measured with the monoclonal antibody assay in patients after cryoprostatectomy.

Serum CK-MB is an unreliable test to diagnose an MI in patients who have undergone cryoprostatectomy.