Dr Oon (second right) is seen with (from left) heart failure specialist Dr Ling Hwei Sung, cardiologist Dr Joshua Chung, Clinical Genetics Malaysia head Dr Ngu Lai Hock, and medical officer Dr Nadia Mohammad Nazri.
KUCHING (Jan 5): The Sarawak Heart Foundation has contributed RM100,000 towards a fund for genetic testing for inherited cardiovascular disease at the Sarawak Heart Centre in Kota Samarahan near here.
The fund was set up in 2021 with RM50,000 from the foundation, and has benefitted 58 patients, including eight children, according to a press release today.
Last year, the genetic testing service was extended to children with inherited cardiovascular disease (mainly inherited aortopathies).
These children are under the careful care of the paediatric cardiology team at Sarawak Heart Centre.
With another contribution of RM50,000 from the foundation last month, the centre will be able to support more children.
Consultant cardiologist Dr Oon Yen Yee, who initiated the fund, said it subsidises or sponsors patients from the lower income group so that genetic testing is accessible to all.
Inherited cardiovascular disease is one that has been passed on through families.
Many cardiac diseases can be inherited, including cardiomyopathy, high cholesterol, arrhythmias, and congenital heart disease, which can affect people of any age.
Dr Oon explained that symptoms reported by patients with inherited cardiovascular include palpitations, fainting spells, shortness of breath, and chest pain.
However, some patients do not display any symptoms, and some may have risk of sudden cardiac death. Contrary to many people’s beliefs, inherited cardiovascular diseases are not uncommon.
At the Sarawak Heart Centre, the most common inherited cardiovascular disease seen is hypertrophic cardiomyopathy (HCM), which is a disease affecting the heart muscle, causing it to thicken abnormally.
“Many patients with HCM under our care, are healthy individuals who display no symptoms. They are usually referred to Sarawak Heart Centre because of abnormal heart findings from a health check.
“Genetic testing can help to confirm the diagnosis of an inherited cardiovascular disease. It can also help to alleviate unnecessary anxiety among family members, because through genetic screening, those who do not carry the gene will not have the disease,” said Dr Oon.
She said not all patients with inherited cardiovascular disease will have a positive genetic test or a pathogenic mutation identified as there are those where genetic testing only picks up a gene variant that is of ‘uncertain significance’.
“Some may even have a negative test. This is because the current scientific data is insufficient to classify the gene variant as a disease-causing variant, or the gene causing the disease has not been identified.
“It does not mean that the patients do not have the disease, and the family screening approach in this group of patients will be different from the group of patients with a pathogenic mutation identified,” she explained.
Dr Oon said genetic testing has also allowed the doctors to provide individualised and targeted treatment for patients with inherited cardiovascular disease.
She cited a case of a patient with heart failure due to Titin gene mutation.
“His mother also suffers from heart failure and has passed down the gene to the patient. Because Titin mutation carries a better prognosis compared to other form of cardiomyopathy, the patient was offered cardiac contractility modulation (CCM) therapy.
“CCM is a relatively new device-based therapy for patients with heart failure. The treatment can help improve heart function. He became the first patient to receive CCM therapy in Southeast Asia, and is now recovering and doing well,” Dr Oon said.
The genetic tests at Sarawak Heart Centre are sent to a US-based company called INVITAE and the current cost of a genetic test is US$349.
When factoring in transportation fees, which range from RM150 to RM200, a patient would need to pay up to RM1,900 for a genetic test.
When a pathogenic mutation is detected in a patient, the company provides free testing to immediate family members, regardless of numbers.
Last year, Sarawak Heart Centre started its cardiogenetic clinic service, making it the first cardiac centre under the Ministry of Health to do so.
The clinic is run with the help of qualified geneticists from Kuala Lumpur Hospital and provides comprehensive cardiovascular evaluations, genetic counselling, genetic testing, and individualised treatment plans for patients with or at risk of inherited cardiovascular disease.
Dr Oon shared that patients often ask, “Will a genetic test change the treatment of our heart disease?”
“Unfortunately, there is currently no cure for most of the inherited cardiovascular diseases. The treatment provided is mainly for symptom alleviation and prevention of sudden cardiac death. But there are studies examining treatment targeted at the mutated gene, and the findings showed promising results. In the future, these investigational treatments called gene therapy might offer a complete cure for inherited cardiovascular disease,” she said.
Dr Oon also brought up the social implications when a person is tested positive for an inherited cardiovascular disease.
“Those who are professional athletes will be advised to stop participating in competitive sports, hence affecting their career and income. Insurance companies may impose certain restrictions or limit on their coverage. And the fear of passing down the gene to their offspring may hinder one from having a child.
“That is why we provide counselling before genetic testing, and when the results are out, another session of counselling will be arranged to explain the test results and the next course of action. We will try our best to help you and your family, so allow us to explain genetic testing to you when it is indicated. There may be no cure for the heart problem at present, but in the future, things might change,” she added.