Twenty-one hypercholesterolemic patients (mean age, 56 years) who were otherwise healthy received 20 mg/day of simvastatin for 6 months. The mean left ventricular ejection fraction (LVEF) decreased from 61% at baseline to 58% after one month (p = 0.02), but returned to the baseline value at three and six months. The authors concluded that simvastatin treatment is not associated with impairment in left ventricular function in hypercholesterolemic patients after 6 months of treatment. The study was funded by Merck Sharp and Dohme (Australia).

Comment: CoQ10 deficiency has been found in myocardial tissue of patients with congestive heart failure, and CoQ10 supplementation improved heart failure in some but not all studies. In the new study, the authors' conclusion did not mention the significant decrease in LVEF that occurred after 1 month of simvastatin treatment. This decrease could be clinically significant for patients with heart failure or marginal myocardial function. There are case reports in which initiation of treatment with a statin drug was followed by cardiac decompensation in patients with previously stable heart failure.

The authors of the new study reported that plasma CoQ10 levels decreased with simvastatin treatment, but that the ratio of CoQ10 to LDL cholesterol actually increased. One could argue that the ratio is more important than the absolute CoQ10 concentration, but neither of those measurements necessarily correlates closely with tissue CoQ10 concentrations. In animal studies, administration of lovastatin or pravastatin resulted in a significant reduction in CoQ10 concentrations in myocardial tissue.

One wonders whether statin-induced heart failure will be the next "Vioxx." Perhaps one day the main question in a class-action lawsuit will be what did the drug companies know and when did they know it regarding the potential of statins to cause heart failure and whether or not CoQ10 could prevent it.

Colquhoun DM, et al. Effects of simvastatin on blood lipids, vitamin E, coenzyme Q10 levels and left ventricular function in humans. Eur J Clin Invest. 2005;35:251-258.