Available evidence indicates that patients with heart failure may benefit from using carnitine. Two studies suggest that in patients with HF, oral carnitine enhances exercise capacity, peak oxygen consumption and arterial and pulmonary blood pressure. One study suggests carnitine reduces echocardiographic end-diastolic dimensions and septal separation. One study measured mortality and found survival rate improved in the carnitine group. Individuals in this study were on ACE-inhibitors. Further research on the effect of carnitine use in patients with heart failure is needed.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.