Media Release


NHCS bridges the care transition from paediatric to adulthood for patients with Tetralogy of Fallot (TOF), a severe form of congenital heart disease, with comprehensive care programme, ranging from screening tests, surgical and minimally invasive medical therapies, to emotional, physical and educational support.

Singapore, 02 November 2022 – Tetralogy of Fallot (TOF) is one of the most common and severe form of congenital heart disease. National Heart Centre Singapore (NHCS) currently sees close to 400 patients with TOF, with the numbers increasing by nearly 5% each year. The majority of these patients transit from their paediatric care at KK Women’s and Children’s Hospital to NHCS under the care of our Adult Congenital Heart Disease (ACHD) Programme from the age of 16 upwards. The ACHD team comprises a multidisciplinary team of doctors, nurses and allied health professionals who monitor these patients closely in outpatient clinics with regular tests such as electrocardiogram (ECG), transthoracic echocardiogram (Echo), and other types of cardiac scans such as computed tomography (CT) or magnetic resonance imaging (MRI).

This programme aims to improve the quality of life of these adult congenital patients with the provision of comprehensive care ranging from regular surveillance of their underlying congenital heart defects to providing appropriate surgical and minimally invasive treatments, as well as psychological and educational support through the patient support group comprising fellow patients and healthcare professionals.

Surgical and minimally invasive treatments

Diagnosed at birth or infancy, TOF patients who have multiple heart defects (Refer to Annex A) would typically undergo surgery to repair the defects, and subsequently, be monitored and followed up closely throughout their life. About half of the patients who survived surgical repair when young usually require a pulmonary valve replacement in their adulthood (within the 20-30 years post-repair) due to narrowing or leaking of their native pulmonary valves which may lead to enlarged and weakened right heart over time.

“Pulmonary valve replacement can be done surgically, or via a minimally invasive method known as Percutaneous Pulmonary Valve Implantation (PPVI) for selected patients who are suitable. In PPVI, a special valve is guided to the heart via a thin catheter through a vein in the leg to repair the faulty pulmonary valve. As it is a minimal invasive procedure, it allows faster and better recovery in patients. Patients are required to continue with medications to strengthen their heart muscle contraction and to control abnormal heart rhythm,” shared Assistant Professor Foo Jie Sheng, Consultant, Department of Cardiology, and member of ACHD Programme, NHCS.

To-date, NHCS has done 9 such procedures, the highest number locally. All patients are currently doing well and continues to be followed up closely.

Support group to help patients better cope with challenges

“TOF is a lifelong heart condition. There are different challenges once patient enters adulthood – from medical and surgical issues requiring regular follow-ups, non-heart related medical problems that may occur, to family planning concerns. Our multidisciplinary ACHD Programme brings together the expertise and experience of various healthcare professionals in one setting to smoothly manage the care of our TOF patients.

We also recognise the psychological, vocational and lifestyle issues that many patients face as they enter adulthood. We have had regular patient support group sessions since 2006 focusing on different congenital heart conditions each year. Our aim is to connect patients with the same type of congenital heart defects and to provide them with information and resources such as latest treatments, mental well-being and lifestyle management. It also allows our patients to reach out to our care team of doctors, nurses and medical social workers,” shared Associate Professor Tan Ju Le, Senior Consultant, Department of Cardiology, and Director, ACHD Programme, NHCS.

When he was just two years old, Mr Alvin Poh underwent the first of many surgeries in his lifetime. Diagnosed with TOF, Alvin who is now 31 years old, used to have breathlessness and heart palpitations if he over exerts himself. An earlier open heart surgery to correct his leaky heart valves could not improve his condition until the availability of PPVI which helped him to recover faster and live better. He is also part of National Heart Centre Singapore’s Tetralogy of Fallot patient support group.

Annex A

Tetralogy of Fallot (TOF) is a congenital heart condition where there are four defects found in the heart. As illustrated in the image below, the defects are:

  1. a hole (ventricular septal defect) between the lower heart chambers (ventricles);
  2. an obstruction from the right ventricle to the lung caused by thickened muscle and/or narrowing of the pulmonary valves (pulmonary stenosis);
  3. the aorta, the major artery which supplies oxygen-rich blood to the rest of the body, lies over the ventricular septal defect; and lastly,
  4. the muscle of the right ventricle being thicker than usual (right ventricular hypertrophy).
These defects cause insufficient oxygen to reach the body, often resulting in a ‘bluish’ appearance in babies and young children.

Diagnosed at birth or infancy, TOF patients have multiple heart defects would typically undergo surgery to repair the defects, and subsequently, be monitored and followed up closely throughout their life. Upon reaching adulthood, there is likelihood of experiencing narrowed or leaky pulmonary valves, leaky aortic valves and abnormal heart rhythms - common problems in TOF patients post-surgical repair. Symptoms include breathlessness, palpitations, lower limb swelling, giddiness and chest pain.