Hypertrophic Cardiomyopathy Oakville

Hypertrophic Cardiomyopathy

What is Hypertrophic Cardiomyopathy?

Hypertrophic cardiomyopathy is a type of cardiomyopathy whereby the heart muscle becomes thickened (hypertrophied) and stiffens. This makes It more difficult for the heart to pump blood to the rest of the body. 

Hypertrophic Cardiomyopathy can be categorized as follows:

graphic of a normal heart vs a heart with Hypertrophic Cardiomyopathy

Obstructive Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy typically leads to muscle thickening along the septal wall of the heart. The septum is the wall separating the two lower chambers of the heart (right and left ventricle). This septal muscle thickening may create an obstruction, and impede proper blood flow out of the heart.  This is called obstructive hypertrophic cardiomyopathy. 

Non-Obstructive Hypertrophic Cardiomyopathy

Sometimes the muscle thickening is located in an area of the heart, that does not impede blood flow as it flows out of the heart.  This may include the right ventricle, the entire left ventricle, or muscle thickening at the apex of the lower chamber (left ventricle). This latter condition is called Apical Hypertrophic Cardiomyopathy, and is also known as Yamaguchi Syndrome. Despite variations in the location of muscle thickening, non-obstructive cardiomyopathy will cause stiffening of the left ventricle, which makes it challenging for the ventricle to relax after each heartbeat. The ventricle subsequently does not fill with blood sufficiently, and therefore sends less oxygen rich blood out of the heart, with the next heartbeat.  

What Causes Hypertrophic Cardiomyopathy and Who Should Be Screened?

Hypertrophic cardiomyopathy typically has a genetic cause, and may appear in multiple family members, throughout generations. Currently there are only a handful of genes identified that cause hypertrophic cardiomyopathy and ongoing research is being conducted to identify the others. 

If a genetic variant is identified in the family member with hypertrophic cardiomyopathy, genetic testing and genetic counseling is important for first degree family members, who may also carry this gene variant. However, this is a unique cardiomyopathy, in that carrying the gene does not necessarily translate into developing hypertrophic cardiomyopathy. It does however allow for improved risk stratification and preventative care strategies.

What are the Symptoms of Hypertrophic Cardiomyopathy?

Although relatively common, hypertrophic cardiomyopathy may go undetected and undiagnosed for many years, as many people have no symptoms in the early stages. As the disease progresses, common symptoms include:

older woman holding her neck in pain due to Hypertrophic Cardiomyopathy

What are the complications of Hypertrophic Cardiomyopathy?

Although Hypertrophic cardiomyopathy is a very complex disease, the complications can be thought of  as falling into 3 categories:

graphic comparison showing a normal heart vs a congestive heart

Heart Failure

Hypertrophic cardiomyopathy produces a type of heart failure that is the result of a stiff left ventricle, rather than a weakened left ventricle.  This is when the left ventricle is unable to relax sufficiently after each heart beat, and therefore is unable to fill with adequate blood for the next heart beat. This leads to less oxygen-rich blood traveling out of the heart to the rest of the body. This is typically called Heart Failure with Preserved Ejection Fraction (HFpEF).  Symptoms include shortness of breath, abdominal distension, leg swelling, weight gain and fatigue. Over time however, if left untreated, the left ventricle can become weak, and the hypertrophic cardiomyopathy can transition to what is called Heart Failure with Reduced Ejection Fraction (HFrEF), or “Burnt out Hypertrophic cardiomyopathy”. This is why prompt and early management with an advanced heart failure specialist is imperative for long term health, and prevention of progression.

Mitral Regurgitation

The mitral valve separates the two chambers on the left side of the heart (left atrium and left ventricle).  When there is an obstruction of blood flowing out of the heart, a force is created that pulls part of the mitral valve leaflet into the outflow passage way, which further obstructs blood flowing out the heart. Consequently, blood now leaks  (regurgitates) from the left ventricle, into the left atrium, as this is the path of least resistance.

computer screen showing Mitral Regurgitation
computer screen showing heart Arrhythmias


The heart muscle cells become rearranged (myocyte disarray), which alters the electrical system of the heart. This makes the heart more likely to trigger arrhythmias such as atrial fibrillation or life-threatening ventricular arrhythmias, which can result in sudden death. Your advanced heart failure specialist may discuss preventative strategies, such as an implantable cardioverter-defibrillator (ICD), depending on your overall risk.

Chahal Cardiovascular Centre in Oakville Favicon

Frequently Asked Questions

Hypertrophic cardiomyopathy is fairly common, with an incidence of 1 in 500 adults, but unfortunately it often goes undiagnosed. In fact, it is the most common cause of sudden death in athletes.

Yes, this is true. Infective endocarditis is an infection of your heart valves or the inner lining of the heart muscle (Endocardium). The infectious agents (typically bacteria) may cause growths or perforations in the valve itself, and may lead to scarring. This ultimately affects the way the valves open and close, and may require valve repair/replacement. Infective endocarditis can even be fatal. The infection is able to seed the heart valves and lining, by traveling in the bloodstream. This most commonly originates from germs that originate in the mouth and around the teeth. It is imperative to take good care of your oral health, including routine dental care, regular brushing, flossing, and ensuring dentures fit appropriately.  While antibiotics are not routinely prophylactically prescribed before dental check-ups in patients with hypertrophic cardiomyopathy, they may be warranted in certain individualized cases, including those with a history of valve repair or replacement.

illustration of a heart showing aortic valve with bacteria and infection vs a normal aortic valve

No this is not exactly true. Moderate intensity aerobic type exercise is quite reasonable for patients with hypertrophic cardiomyopathy, as this improves overall cardiovascular health. However, weight training and high intensity aerobic exercise, such as competitive sports, and high intensity interval training are strongly discouraged due to the risk of ventricular arrhythmias and sudden cardiac death. 

Before beginning an exercise program, please discuss this with your cardiologist, who will be able to advise you based on your individualized risk assessment.

Still have a question about hypertrophic cardiomyopathy? Speak to your doctor about a referral to the Chahal Cardiovascular Centre for an Advanced Heart Failure consultation.