Medical advancements mean many rare diseases are now being diagnosed and getting treated earlier. Take the case of homemaker Shafeena (name changed) who lives in Trichur, Kerala. The 45-year-old saved herself and some members of her family thanks to her own timely diagnosis of hypertrophic cardiomyopathy (HCM), which was earlier considered a rare disease. In HCM, the heart muscle thickens, making it difficult for the heart to pump oxygen and nutrient-rich blood to the body.
Shafeena developed shortness of breath and suffered the condition for six months before she consulted experts at the Amrita Institute of Medical Sciences and Research, Kochi, Kerala, in 2012. After an investigation, following evaluation protocols for inherited cardiac disease, the experts realised that Shafeena’s family had a history of nine sudden cardiac deaths. Of them, six deaths occurred in young individuals below 35 years of age. They all died in their sleep.
Lipoprotein (a): A marker to identify heart attack risk
Oil is well? Yes, but conditions apply
Yes, children too can have high blood pressure
Silent or vague symptoms of heart attack put women at risk
Shafeena was recognised with a high risk for sudden cardiac death and an AICD (automatic implantable cardioverter defibrillator) was implanted in her chest. Her two siblings also received an AICD to prevent sudden cardiac death. The doctors also diagnosed HCM in seven other family members, including two of Shafeena’s siblings and one of her children.
“A comprehensive genetic analysis was performed on Shafeena, and a rare and unique genetic abnormality was detected,” says Dr Hisham Ahamed, project lead, hypertrophic cardiomyopathy clinic and registry, Amrita Institute of Medical Sciences and Research. “This genetic information was then used to identify members of the next generation, and we managed to identify children who are likely to develop this disease and guide their follow-up.”
What is hypertrophic cardiomyopathy?
“[In HCM] the heart muscles get so thick that it obstructs the flow of blood coming out of the heart,” says Dr Refai Showkathali, senior consultant, interventional cardiologist, Apollo Hospital, Chennai. “It is an autosomal dominant disorder and found more among men. In very rare situations, it can also lead to sudden cardiac death.”
He says HCM was earlier detected only during autopsy on a victim of sudden cardiac death. But today, with the help of technology, the condition can be detected early.
Dr Showkathali says in the West, sports clubs screen athletes for heart conditions before enrolling them. He strongly recommends that people interested in pursuing high-intensity workouts or sporting activity should undergo prior screening.
There are several types of HCM, and the thickening of the heart muscle can vary and happen in different areas of the heart. Depending on where the thickening is, Dr Ahamed says, it can cause:
- stiffness of muscle, making it harder for the main pumping chamber to fill with blood that is pumped out to the body. This is called non-obstructive HCM
- limitation or blocking of blood flow from the heart to the body, forcing the heart to work harder. This is called obstructive HCM. Sometimes, non-obstructive can turn to obstructive HCM upon exercise or exertion as blood flow out of the heart gets blocked or slowed
- irregular beating or rhythm of heart (arrhythmias)
How common is it?
HCM is one of the most common inherited cardiovascular diseases. It is estimated to now affect one in every 200 persons. “If a parent has HCM, there is 25 per cent chance that one of the kids will have it too,” Dr Refai says. “One in four children can carry the condition. If there is a history of sudden cardiac death in the family, it is recommended that children of age 15 or 16 years undergo the screening.”
Who are at risk of HCM?
If a family member has evidence of HCM, it is then recommended that all family members get screened too. A clinical examination is done through electrocardiogram (ECG), echo or genetic testing.
Mostly, HCM tends to develop as the person grows, presenting in the late teens or early 20s. But if a parent has HCM, screening examinations for children starting from five years of age is advised. In case of an aggressive form of the disease, experts may advise screening children younger than five years. This screening is repeated at intervals of three to five years till about the age of 40, says Dr Ahamed.
HCM patients can be diagnosed at any age, from birth to the age of 80 and beyond. Infants born with HCM may develop serious complications such as heart failure.
Symptoms of HCM
The symptoms of HCM may vary from mild to severe symptoms, says Dr Ahamed. They include:
- Shortness of breath, especially when exercising or being active
- Dizziness or fainting (may or may not be related to exertion)
- Chest pain
- Pressure on the chest
- Fluttering of the heart or heart palpitations
- Overly tired or little energy to do usual activities
Treatment and management
Dr Ahamed says the treatment for HCM depends on the following factors:
- Severity of symptoms, including any signs of heart failure or irregular heart rhythms
- How thick is the heart muscle and if it is blocking or slowing blood flow from the heart to the body
- How well the heart is working overall
- Risk of sudden cardiac death
- How HCM is affecting your life
- The patient’s goals and preferences for care
At present, the increased thickness of the heart walls in HCM is not reversible. But Dr Ahamed says that in obstructive type of HCM, which leads to severe heart failure symptoms, surgical options exist to excise a portion of the thickened segment to relieve the obstruction.
How to lead an almost-normal life with HCM
HCM is not curable but can only be managed with the necessary treatment options and regular follow-ups with experts. “A large body of evidence gathered over the last half a century has clearly shown that with proper evaluation, risk stratification and treatment, along with regular follow-up, most people with HCM can have a near-to-normal life expectancy,” says Dr Ahamed.
A 2016 study by corresponding author Barry J Maron, also a cardiologist based in Boston, calls HCM a contemporary treatable genetic disease and says it is now possible to achieve significantly improved survival with a low HCM-related mortality of 0.5 per cent per year across all ages.
The study further states that these clinical-management initiatives, instituted by the practising cardiology community, have succeeded in preserving life and restoring an active lifestyle for thousands of patients with HCM, while providing many with a measure of reassurance and a reasonable expectation for an extended (if not normal) lifespan.
Dr Showkathali says HCM patients should ensure they have prescribed medicines on time and have plenty of liquids, much more than a normal person. “The patient should also undergo regular checks, avoid high-level sporting activity and seek immediate medical help in case of suspicion of giddiness,” he says.