More Singaporeans are living longer and developing heart valve disease
Patients' lack of knowledge and fear of open heart surgery stymie the treatment of heart valve disease. But combating the disease is now easier, says National University Heart Centre of Singapore's Dr Edgar Tay.
SINGAPORE: With an average life expectancy of about 83 years, Singaporeans live longer than most of the rest of the world, coming in third after Japan and Switzerland, in the longevity stakes.
Our healthy life expectancy, the number of years one lives in “full health”, is an impressive 74 years, and second in the world.
This can be credited to general improvements in living standards, greater access to healthcare, and better dietary and lifestyle habits.
Reduction in risk factors such as smoking, and better control of hypertension and cholesterol levels have also lowered deaths from a once top killer: Coronary heart disease, where narrowed heart arteries hinder blood and oxygen from reaching the heart muscle, and may trigger a heart attack.
Japan’s success in tackling it has enabled the country to snag the top spot in longevity worldwide.
Ironically, following increased longevity is the emergence of another type of cardiovascular disease: Degenerative heart valve disease.
The prevalence is about 2.5 per cent in patients in industrialised countries globally and increases to about 8 per cent in patients aged 65 to 74, and more than 12 per cent in patients 75 years or older.
HEART VALVES AND THEIR IMPORTANCE
Heart valves are thin membranes attached to the heart wall that constantly open and close to direct the flow of blood in a single direction, through the heart chambers, and then to the rest of the body.
Valves open and close with each heartbeat, which means that, by the time we reach 80 years of age, they would have performed this action more than three billion times. Over the years, these valves degenerate with calcium deposits building up and fibrous scarring.
One study estimated that one in eight patients over the age of 75 all over the world would have moderate to severe heart valve disease.
Heart valves may fail to open, making it difficult for blood to flow through. This is especially common in the aortic valve, the gateway through which blood flows from the heart chamber to supply oxygen and nutrients to the rest of the body. Its narrowing or failure to open leads to heart failure and reduced blood supply to the organs.
Patients often only take action when the symptoms of breathlessness or chest pains become unbearable. But by the time they show up at the doctor’s, the disease may have advanced significantly. Many never make it there.
Previously, the tools available to the physician were limited to the stethoscope and a thorough physical examination.
While these tools remain the cornerstone of good medical care, today’s imaging tools such as echocardiography, enable accurate diagnosis and disease detection even before the patient develops symptoms. Imaging tools allow the physicians to see the heart and assess its functioning in real time.
When time is of the essence, such technology can make the difference between life and death.
THE PROMISE OF NON-INVASIVE SURGERY
Diagnosis is merely the first step, and appropriate treatment is the other half of the battle. Medication may help alleviate some symptoms but the diseased valve will need to be treated through surgery or with some other medical intervention.
The conventional treatment for aortic valve stenosis is open heart surgery and it is well established that this leads to improved survival rates and quality of life.
Yet, a study conducted 10 years ago found that 40 per cent of Singaporean patients turned down the option of surgery.
A fear of invasive surgery, lack of understanding of the treatment, or the impact of such treatment are plausible reasons for their responses. After all, the image of lying under fluorescent operating lights with one’s chest cut open is a chilling one.
Annie*, a patient in her late 70s, had breathlessness and felt exertion when carrying out daily activities. For years, I had advised her to undergo open heart surgery but she refused because of a fear of going under the knife.
She had no choice but to reduce her household chores and movements, slowly becoming homebound and bedbound, losing years of good quality of life, and finally succumbing to the disease a few years later.
It was unfortunate because surgery could have helped prolong her life and given her many more years of healthy living.
Fortunately, significant progress has been made in the treatment of valve diseases over the past decade, reducing the need for invasive surgery.
Transcatheter aortic valve implantation can treat aortic valve stenosis without the need for open heart surgery. Instead, a catheter or tube is used to deliver a collapsible replacement valve to the obstructed aortic valve to take over the regulation of blood flow.
Unlike open surgery, which involves opening the breast bone and arresting the heart, it is a less invasive procedure that can allow for faster recovery, in addition to a shorter hospital stay and down time.
It is also suitable for a wider range of patients, many of whom may be in their 80s, or suffer from other medical conditions that make open heart surgery unsuitable.
This treatment is now the standard of care for patients whose conditions are deemed unsuitable for surgery.
Such breakthrough therapies are significant. The availability of such alternatives have resulted in a significant increase in patients seeking treatment.
In the United States, 20 per cent more patients were willing to undergo and received various kinds of surgery and treatment for aortic stenosis, with the introduction of the transcatheter aortic valve implantation method.
It seems giving people choice was key.
As with all healthcare breakthroughs, we should combine cautious optimism with rigorous evaluation – not least on whether such treatment options are readily available and affordable to patients.
For what good is life-changing technology if it is out of reach for those who need it most?
The cost and accessibility of these new treatments must not be neglected.
Apart from Japan, in most countries in Asia including Singapore, the procedure is either only partially subsidised or not at all. Some are assessing the cost effectiveness of such therapies before deciding how to fund them.
Increasing awareness of and openness to such therapies could help push them into the mainstream and bring costs down. There should also be active consideration to include such treatment under schemes such as Medisave, opening up options to more people.
With low birth rates, low mortality and high longevity, we are on the cusp of a silver tsunami. Whether we sink or surf is partly down to what we make of the technology available to us.
Dr Edgar Tay is a senior consultant at the Department of Cardiology, National University Heart Centre Singapore.
*Not her real name.