Cardiomyopathy:
Cardiomyopathy is a general term for diseases of the heart muscle, where the walls of the heart
chambers have become stretched, thickened, or stiff. This affects the heart's ability to pump blood
around the body (NHS,2023). There are four types of cardiomyopathies:
1. Hypertrophic cardiomyopathy (HCM)
2. Dilated cardiomyopathy (DCM)
3. Restrictive cardiomyopathy (RCM)
4. Arrhythmogenic cardiomyopathy (ACM)
Hypertrophic Cardiomyopathy (HCM):
Hypertrophic Cardiomyopathy (HCM) is a genetic cardiovascular disease in which the muscles of the
heart walls become abnormally thick making it difficult to pump blood (Maron and Maron, 2013).
HCM is caused by the mutation of sarcomeric proteins however, the specific cause of the underlying
mutation remains unknown (Geske, Ommen and Gersh, 2018). HCM can be grouped into non-
obstructive and obstructive cardiomyopathy. Non-obstructive hypertrophic cardiomyopathy occurs
when the left ventricular wall becomes thickened and stiff resulting in a reduced amount of blood
being pumped out in one heartbeat. In obstructive hypertrophic cardiomyopathy, the septum
between the right and left ventricular chambers becomes thickened which can cause a blockage to
the aorta from the left ventricle.
Although Hypertrophic Cardiomyopathy is the most frequent cause of sudden death in young
people, the condition can often go undiagnosed. According to Frey, Luedde, and Katus, (2011), HCM
is the most-common cause of sudden cardiac death in people under 35 years of age. Hypertrophic
Cardiomyopathy can be diagnosed by echocardiograms, MRI, ECG, exercise tests and genetic testing.
According to the British Heart Foundation (2021), approximately 1 in 500 people in the UK have a
known case of hypertrophic cardiomyopathy, however there may be many more cases in people
who present no symptoms. People suffering with HCM are at risk for developing other conditions
such as sudden cardiac death, heart failure, mitral valve issues, abnormal cardiac rhythm
(Arrythmias) and blocked blood flow to and from the heart (Gore and Swami, 2021). Many people
with HCM live very normal lives and may not even experience any symptoms, however in some
cases, symptoms can develop and become worse over time. In most cases, symptoms can be
, managed with medication however, some individuals may need an implantable cardioverter
defibrillator (ICD) inserted and others may have a pacemaker inserted to maintain a healthy sinus
rhythm.
Hypertrophic Cardiomyopathy is a chronic progressive condition that will worsen over time. As HCM
progresses, it can lead to the development of other conditions. For example, people suffering from
HCM have a higher risk of developing atrial fibrillation which can lead to blood clots, stroke, and
other complications (American Heart Association, 2021).
Signs & Symptoms of HCM:
Many people live normal symptom free lives with HCM, and sudden death may be the first
disease presentation.
Other non-specific symptoms may be, SOB, chest pains, palpitations, and dizzy spells or
blackouts.
May be a jerky carotid pulse, heaving cardiac apex beat, and basal systolic murmur and
fourth heart sound.
May develop mitral regurgitation and abnormal heart rhythms.
Dilated Cardiomyopathy (DCM):
Dilated cardiomyopathy is a primary disorder
of cardiac muscle, characterised by dilation,
thinning, and dysfunction of the left and
sometimes right ventricles (Hobbs et al.,
2011). This leads to inefficiency of the heart
to contract due to the dilated and thinning
muscle. About a third of cases of completely
‘idiopathic’ dilated cardiomyopathy may have
a family history, with variable genetic
inheritance. It may also present in the late
stages of pregnancy or postpartum; some
cases of peripartum cardiomyopathy
deteriorate rapidly and may need to be
considered for urgent ventricular assist
devices and transplantation.
Restrictive Cardiomyopathy (RCM):
Restrictive cardiomyopathy is rare. It's most often
diagnosed in children, although it can develop at
any age (NHS, 2023). This is when the walls of the
heart become stiff and rigid. This prevents the
chambers of the heart from relaxing completely
and being able to fill up with blood, therefore it
restricts the heart’s ability to pump blood
effectively.
