Elevated CK-MB isoenzyme after exercise stress test and atrial pacing in patients with ischemic heart disease

Area of Science:

• Cardiology
• Biochemistry
• Clinical Diagnostics

Background:

• Cardiac biomarkers are crucial for diagnosing myocardial ischemia.
• Creatine kinase-MB (CK-MB) isoenzyme is a specific marker for cardiac injury.
• Understanding CK-MB release kinetics during exercise stress is vital for accurate diagnosis.

Purpose of the Study:

• To investigate the release of CK-MB isoenzyme following exercise stress testing in patients with ischemic heart disease.
• To compare CK-MB release patterns between patients with ischemic heart disease and healthy controls.
• To assess the immediate impact of acute ischemia on CK-MB and total CK levels.

Main Methods:

• Utilized a highly sensitive monoclonal antibody kit for CK-MB detection.
• Monitored CK-MB levels 4–6 hours post-exercise stress test in 15 ischemic heart disease patients and 18 healthy controls.
• Measured CK-MB and total CK levels in coronary sinus blood within 10–30 minutes of induced acute ischemia via atrial pacing in 5 coronary artery disease patients.

Main Results:

• Significant CK-MB isoenzyme release was detected 4–6 hours post-exercise in 66% of ischemic heart disease patients versus 5.6% of healthy controls.
• Atrial pacing induced acute ischemia led to a drastic elevation in CK-MB (2.04 ± 2.06 ng/L to 10.88 ± 6.9 ng/L, p < 0.001) and a significant increase in total CK (21 ± 12 IU/L to 52 ± 14 IU/L, p < 0.01).
• These findings indicate a correlation between exercise-induced ischemia and CK-MB release.

Conclusions:

• Exercise stress testing can reveal significant CK-MB isoenzyme release in patients with ischemic heart disease.
• The observed CK-MB release is significantly higher in patients with ischemic heart disease compared to healthy individuals.
• Further investigation in larger cohorts is warranted to establish the definitive clinical significance of CK-MB release during exercise.