Background: Congestive heart failure depletes the myocardium of carnitine, coenzyme Q10 (CoQ10), and taurine--substances known to influence mitochondrial function and cell calcium. We hypothesized that feeding patients a nutritional supplement that contained carnitine, CoQ10, and taurine would result in higher myocardial levels of these nutrients and improve left ventricular function.
Methods: Forty-one patients who underwent aortocoronary artery bypass with an ejection fraction < or =40% at referral were randomly assigned to a double-blind trial of supplement or placebo. Radionuclide ventriculography was performed at randomization and before surgery. Surgical myocardial biopsies, adjusted for protein content, were analyzed for carnitine, CoQ10, and taurine levels.
Results: The groups were well matched. Minor exceptions were supplement group versus placebo group for digoxin use (7 vs 0, respectively; P =.009) and age (62 +/- 11 years vs 69 +/- 5 years, respectively; P =.04). There were significantly higher levels in the treated group compared with the placebo group for myocardial levels of CoQ10 (138.17 +/- 39.87 nmol/g wet weight and 56.67 +/- 23.08 nmol/g wet weight; P =.0006), taurine (13.12 +/- 4.00 micromol/g wet weight and 7.91 +/- 2.81 micromol/g wet weight; P =.003), and carnitine (1735.4 +/- 798.5 nmol/g wet weight and 1237.6 +/- 343.1 nmol/g wet weight; P =.06). The left ventricular end-diastolic volume fell by -7.5 +/- 21.7 mL in the supplement group and increased by 10.0 +/- 19.8 mL in the placebo group (P =.037).
Conclusions: Supplementation results in higher myocardial CoQ10, taurine, and carnitine levels and is associated with a reduction in left ventricular end-diastolic volume in patients with left ventricular dysfunction before revascularization. Because the risk of death for surgical revascularization is related to preoperative left ventricular end-diastolic volume, supplementation could improve outcomes.