Is melatonin (Melatonin) contraindicated in Coronary Artery Bypass Graft (CABG) patients?

Melatonin Use in CABG Patients

Melatonin is not contraindicated in CABG patients and may actually provide benefits for sleep quality and potentially reduce oxidative stress during the perioperative period.

Evidence on Melatonin in CABG Patients

The ACC/AHA guidelines for CABG surgery do not list melatonin among contraindicated medications 1. While the guidelines provide detailed recommendations on various medications including beta-blockers, statins, antiplatelet agents, and hormonal therapies, there is no mention of melatonin as a contraindicated substance.

The only hormonal therapy specifically contraindicated in the guidelines is postmenopausal hormone therapy (estrogen/progesterone), which should not be administered to women undergoing CABG 1.

Potential Benefits of Melatonin in CABG Patients

Several studies suggest melatonin may actually be beneficial in CABG patients:

1. Sleep Quality Improvement:

   • Melatonin (3mg) improved postoperative sleep quality compared to Oxazepam in CABG patients 2
   • This is particularly relevant as sleep disturbance is common after cardiac surgery

2. Oxidative Stress Reduction:

   • Preoperative melatonin (10mg daily for 1 month) significantly increased Nrf2 concentration, potentially enhancing antioxidant defense mechanisms during CABG 3
   • Melatonin (12mg sublingual) before surgery reduced inflammatory markers (hs-CRP, CK-MB) and duration of atrial fibrillation post-CABG 4

3. Myocardial Protection:

   • High-dose melatonin (20mg) showed dose-dependent protective effects against myocardial ischemia-reperfusion injury, with significant reductions in cardiac injury markers (troponin-I, IL-1β) 5

Dosing Considerations

The effective doses used in studies varied:

• 3mg daily for sleep improvement 2
• 10-20mg daily for myocardial protection 3, 5
• 12mg sublingual pre-surgery for reducing inflammatory markers 4

Limitations and Considerations

1. While physiological doses (3mg) of melatonin may improve sleep, they may not be sufficient to prevent ischemia-reperfusion injury; pharmacological doses may be required for antioxidant effects 6

2. The ACC/AHA guidelines do not specifically address melatonin use, suggesting it is not considered a medication of concern in the CABG perioperative period 1

3. The comprehensive anticoagulation management guidelines for CABG also do not mention melatonin as a medication requiring special consideration 7

Clinical Recommendation

For CABG patients experiencing sleep disturbances, melatonin may be considered as an alternative to benzodiazepines, with potential additional benefits of reducing oxidative stress and inflammation. Higher doses (10-20mg) may provide more significant cardioprotective effects than lower doses (3mg).

When considering melatonin use in CABG patients, monitor for any individual adverse reactions, though studies have not identified significant safety concerns specific to this population.