Related Experiment Videos
Cardiac isoenzymes following heart transplantation
J S Ladowski1, M Sullivan, M H Schatzlein
1Northern Indiana Heart Institute, Fort Wayne.
Insights
Post-heart transplant (HT) creatine phosphokinase (CPK) isoenzyme levels do not predict patient outcomes. This study found no correlation between CPK-MB levels and one-year survival, rejection, or graft dysfunction, leading to discontinuation of routine CPK-MB monitoring.
Area of Science:
- Cardiology
- Transplantation Immunology
- Biochemistry
Background:
- Creatine phosphokinase (CPK) isoenzymes, specifically CPK-MB, are frequently measured post-heart transplantation (HT) to assess donor heart myocardial injury.
- The clinical utility of routine CPK-MB monitoring after HT has not been definitively established.
Purpose of the Study:
- To retrospectively evaluate the predictive value of post-transplant CPK-MB levels on the outcomes of orthotopic heart transplantation.
- To determine if elevated CPK-MB levels correlate with mortality, rejection, coronary artery disease, or graft dysfunction.
Main Methods:
- Retrospective analysis of 56 orthotopic heart transplant recipients with at least two daily CPK-MB measurements post-HT.
- Patients were categorized into entirely negative (NEG) and persistently positive (POS) CPK-MB groups.
- Comparison of one-year survival, 3-month freedom from treated rejection, 3-year freedom from coronary artery disease (CAD), and 1-year ejection fraction between NEG and POS groups.
Main Results:
- No significant differences were observed between the NEG and POS groups in donor organ ischemic times or follow-up duration.
- One-year survival rates were similar (84% vs. 74%).
- Rates of freedom from treated rejection at 3 months (39% vs. 42%) and freedom from CAD at 3 years (83% vs. 86%) were comparable. Donor heart ejection fractions at 1 year were also similar (64% vs. 59%).
Conclusions:
- Post-transplant myocardial injury, indicated by CPK-MB levels, does not reliably predict one-year mortality, rejection risk, CAD development, or long-term graft dysfunction.
- Routine CPK-MB monitoring after heart transplantation is not clinically useful for predicting patient outcomes.
- Discontinuation of routine CPK-MB testing post-HT may lead to more economical healthcare practices.
Abstract:
Creatine phosphokinase (CPK) isoenzymes are commonly obtained after heart transplantation (HT) to assess myocardial injury of the donor heart. This investigation retrospectively evaluated the utility of this practice. Fifty-six recipients of orthotopic heart transplants had at least two daily CPK-MB studies following HT. All patients were followed up for at least one year (or until death). Nineteen patients had entirely negative CPK-MB determinations (NEG). Eighteen patients had a single positive CPK-MB determination, and were considered to be equivocal (EQUIV). Nineteen patients had more than one daily positive CPK-MB determination (POS). To evaluate the influence of positive CPK-MB determinations on the outcome of HT, we compared the results in the NEG and POS groups. There was no difference in the donor organ ischemic times between the two groups. The duration of follow-up for the two groups was also similar (1,192 days vs 1,020 days). The NEG and POS groups had no significant difference in: 1 year survival (84 percent vs 74 percent); freedom from treated rejection episodes in 3 months (39 percent vs 42 percent); and freedom from coronary artery disease (CAD) at 3 years (83 percent vs 86 percent). Additionally, the ejection fractions of the donor hearts were similar at 1 year post-transplant for the 2 groups (64 percent vs 59 percent). We conclude that myocardial injury, as reflected by post-transplant CPK-MB levels, does not predict one-year mortality, predisposition to rejection, predisposition to coronary artery disease, or ultimate graft dysfunction. In an effort to perform HT more economically, we no longer obtain CPK-MB levels following HT.