Related Experiment Videos
Serum CK-MB activity during and after aortocoronary bypass surgery
Insights
Cardiac enzyme monitoring after bypass surgery reveals elevated creatine kinase-MB (CK-MB) levels predict myocardial infarction. New Q waves on ECGs underestimate the incidence of perioperative infarction.
Area of Science:
- Cardiology
- Biochemistry
Background:
- Aortocoronary bypass surgery is a major cardiac procedure.
- Assessing perioperative myocardial infarction is crucial for patient outcomes.
Purpose of the Study:
- To evaluate the utility of serum creatine kinase-MB (CK-MB) and total CK levels in detecting perioperative myocardial infarction following bypass surgery.
- To compare CK-MB levels and ECG findings (new Q waves) in identifying infarction.
Main Methods:
- Frequent serum sampling of CK-MB and total CK in 100 patients undergoing bypass surgery.
- Ion exchange chromatography used for CK-MB determination.
- Monitoring occurred during and up to 48 hours post-surgery.
Main Results:
- Significantly higher serum CK-MB levels (peak 46.1 +/- 5.2 u/L vs. 31.3 +/- 2.2 u/L) were observed 6-16 hours postoperatively in patients with new Q waves.
- Total CK levels did not show significant differences.
- New Q waves on ECGs were present in only half of cases with abnormal CK-MB curves, underestimating infarction incidence.
Conclusions:
- Elevated serum CK-MB levels are a more sensitive indicator of perioperative myocardial infarction than new Q waves on ECG.
- Myocardial infarction typically occurs intraoperatively or early postoperatively, as indicated by peak CK-MB levels within 16 hours.
Abstract:
Frequent serum sampling of CK-MB and total CK levels was carried out in 100 patients during and up to 48 hours following aortocoronary bypass surgery. Using an ion exchange chromatography method for CK-MB determination, significantly higher serum CK-MB levels (peak 46.1 +/- 5.2 cf. 31.3 +/- 2.2 u/L), but not total CK levels were present 6 to 16 hours postoperatively in those with new Q waves in the ECG. Serum levels of CK-MB in those patients with uncomplicated surgery were defined. New post-operative Q waves were seen in only one half of cases with frankly abnormal CK-MB curves and seriously underestimated the incidence of perioperative infarction. Peak levels of CK-MB in patients with new Q waves occurred within 16 hours of surgery suggesting that infarction is usually an intraoperative or early post-operative event.