Evaluating direct intra-aortic adenosine administration for myocardial protection in cardiac surgery: A prospective pilot study

Myocardial ischemia-reperfusion injury continues to be a major contributor to postoperative cardiac dysfunction after cardiac surgery. Adenosine, has been investigated as an adjunctive therapy to limit this injury; However, evidence supporting its intraoperative evidence, remains controversial.

In this randomised, single-centre comparative study, we enrolled 99 patients who had heart surgery at our cardiac center. Patients were randomly assigned to two groups: the intervention group receiving intraoperative adenosine (direct injection into the ascending aorta immediately after aortic cross-clamps and prior to cardioplegia) and the control group, which received standard cardioplegia as monotherapy. Postoperative myocardial damage was evaluated by the determination of serum troponin levels 24 hours after surgical intervention.

There was no statistically significant difference between the adenosine group and the control group in post-operative troponin levels. Myocardial injury was more strongly correlated with procedural factors, including surgical and graft size, than with adenosine use. No serious adverse reactions related to adenosine have been documented.

Direct intra-aortic adenosine administration did not significantly reduce postoperative troponin levels compared with standard cardioplegia. Its cardioprotective effects may depend on dosing, timing, and route administration, highlighting the need for larger randomized studies.