Some babies and children will need medicines to help strengthen the heart muscle, lower their blood pressure, and help the body get rid of extra fluid. The following classes of drugs may be prescribed for children with Congenital Heart Disease.

  • ACE Inhibitors
    Captopril (Capoten); Enalapril (Vasotec); Lisinopril (Prinivil, Zestril).
  • Antiplatelet agents / Anticoagulants
    Aspirin: Warfarin (Coumadin)
  • Diuretic agents
    Furosemide (Lasix); Spironolactone (Aldactone)

About Warfarin

  • Warfarin is an anticoagulant that has been used for more than five decades to prevent the formation of blood clots.
  • There are two brands of Warfarin used in Australia (Coumadin and Marevan). The two ‘types’ are delivered in different tablet strengths (and colours) and are not inter changeable for this reason.
  • Warfarin is taken once daily and should be taken at around the same time each day to eliminate fluctuations of drug concentration in the body.
  • It takes two to three days for Warfarin to take effect and the duration of action of a single dose of warfarin is two to five days.
  • Warfarin works by blocking the formation of Vitamin K dependent clotting factors.
  • The International Normalised Ratio (INR) is a test used to determine the effects of the warfarin. It measures how long it takes for the blood to clot. The higher the INR, the longer it takes for the blood to clot.
  • Diet plays an important role in the efficacy of Warfarin as foods high in Vitamin K counteract the effects of the drug. Some foods (e.g. Cranberries) can also increase the effect of Warfarin and may lead to bleeding problems. This does not mean foods high in Vitamin K need to be avoided. However it is important that the diet of the patient provides a consistent amount of Vitamin K to ensure that INR stays stable.
  • Some medications and the general health of the patient can change the efficacy of Warfarin. It is important that the medical professional managing the warfarin dosage of the patient be advised of any changes in this regard as additional INR testing may be needed to determine if Warfarin dosage need to be changed.
  • The effects of Warfarin can be reversed by discontinuing its use or by administering vitamin K1.

Further Reading

  • ENT Wellbeing
    Warfarin Diet

    Synopsis: Warfarin diet – what foods should I eat if I am taking warfarin? What is warfarin? INR? Warfarin and diet. How does diet play a role? What foods are high in vitamin K? Should foods with vitamin K be eaten as part of a warfarin diet? Warfarin diet summary.

INR Testing
INR can be tested either by a venous blood test or by using a Coaguchek INR monitor. The Coaguchek is a device that allows patients to determine their INR quickly by drawing a drop of blood from the fingertip and applying it to a test strip loaded into the device. The monitor analyses the blood and gives an accurate INR reading. More information about the monitor can be found by visiting the Roche website below.

Home Monitoring of INR
The Royal Children’s Hospital Anticoagulation Service facilitates the INR Home monitoring Program for families residing in Victoria and Tasmania. More information about this service can be found at their Information for Families webpage. Other centres in Australia may also provide similar services. Please contact them or HeartKids Australia to find out what may be available in your local area.

Hearts of Hope Australia may also be able to assist families in acquiring a Coaguchek INR Monitor. Please visit our Programs (MEAP) page for further information.

Further Reading

Bone Density in Children on Long-Term Warfarin Therapy
A research study carried out at the Royal Children’s Hospital, Melbourne suggests that long-term Warfarin usage may reduce the bone density of children. It also states that exercise intervention trials have demonstrated a beneficial and durable effect of high-impact exercise on bone density of children. Exercise programs incorporating jumping have been shown to improve bone mass and may have limited demand on the cardiovascular system of children with Congenital Heart Disease

The study recommends that children on long-term Warfarin be screened for reduced bone density.

Further Reading