Coenzyme Q10 therapy before cardiac surgery improves mitochondrial function and in vitro contractility of myocardial tissue

J Thorac Cardiovasc Surg. 2005 Jan;129(1):25-32. doi: 10.1016/j.jtcvs.2004.03.034.


Objectives: Previous clinical trials suggest that coenzyme Q(10) might afford myocardial protection during cardiac surgery. We sought to measure the effect of coenzyme Q(10) therapy on coenzyme Q(10) levels in serum, atrial trabeculae, and mitochondria; to assess the effect of coenzyme Q(10) on mitochondrial function; to test the effect of coenzyme Q(10) in protecting cardiac myocardium against a standard hypoxia-reoxygentation stress in vitro; and to determine whether coenzyme Q(10) therapy improves recovery of the heart after cardiac surgery.

Methods: Patients undergoing elective cardiac surgery were randomized to receive oral coenzyme Q(10) (300 mg/d) or placebo for 2 weeks preoperatively. Pectinate trabeculae from right atrial appendages were excised, and mitochondria were isolated and studied. Trabeculae were subjected to 30 minutes of hypoxia, and contractile recovery was measured. Postoperative cardiac function and troponin I release were assessed.

Results: Patients receiving coenzyme Q(10) (n = 62) had increased coenzyme Q(10) levels in serum (P = .001), atrial trabeculae (P = .0001), and isolated mitochondria (P = .0002) compared with levels seen in patients receiving placebo (n = 59). Mitochondrial respiration (adenosine diphosphate/oxygen ratio) was more efficient (P = .012), and mitochondrial malondialdehyde content was lower (P = .002) with coenzyme Q(10) than with placebo. After 30 minutes of hypoxia in vitro, pectinate trabeculae isolated from patients receiving coenzyme Q(10) exhibited a greater recovery of developed force compared with those in patients receiving placebo (46.3% +/- 4.3% vs 64.0% +/- 2.9%, P = .001). There was no between-treatment difference in preoperative or postoperative hemodynamics or in release of troponin I.

Conclusions: Preoperative oral coenzyme Q(10) therapy in patients undergoing cardiac surgery increases myocardial and cardiac mitochondrial coenzyme Q(10) levels, improves mitochondrial efficiency, and increases myocardial tolerance to in vitro hypoxia-reoxygenation stress.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Aged
  • Analysis of Variance
  • Biomarkers / analysis
  • Coenzymes
  • Coronary Artery Bypass / methods
  • Coronary Disease / pathology
  • Coronary Disease / surgery*
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Elective Surgical Procedures
  • Female
  • Heart Function Tests
  • Hemodynamics / physiology
  • Humans
  • In Vitro Techniques
  • Length of Stay
  • Male
  • Middle Aged
  • Mitochondria, Heart / drug effects*
  • Myocardial Contraction / drug effects*
  • Preoperative Care / methods*
  • Probability
  • Reference Values
  • Risk Factors
  • Sensitivity and Specificity
  • Treatment Outcome
  • Troponin I / analysis*
  • Ubiquinone / analogs & derivatives*
  • Ubiquinone / therapeutic use*


  • Biomarkers
  • Coenzymes
  • Troponin I
  • Ubiquinone
  • coenzyme Q10