Is Cardiomyopathy Always Hereditary?
The exact causes of cardiomyopathy are unknown, but genetics is known to be a risk factor for cardiomyopathy. If your doctors found out that the cause of your illness has a genetic root then they will classify it as hereditary cardiomyopathy.
Hereditary cardiomyopathy is also known as congestive cardiomyopathy, familial idiopathic cardiomyopathy, FDC, primary familial dilated cardiomyopathy.
A genetic heart disease that occurs when your heart or cardiac muscle turns thin and weak in at least a chamber of your heart, as a result causing the open area of that chamber to turn enlarged or dilated is familial dilated cardiomyopathy. Furthermore, your heart is not able to pump out blood as effortlessly as usually it should be. For compensating such actions, your heart takes a chance to raise the amount of blood, which is being pumped via your heart and then it leads to further more thinning and weakening of your cardiac muscle. Eventually, this type of conditions results in a heart failure.
Effects of Familial Dilated Cardiomyopathy
The effects usually take long years for showing symptoms of familial dilated cardiomyopathy to cause various health issues. Even though familial dilated cardiomyopathy starts showing its symptoms in people who are in mid-adulthood stage, it can also occur to infants or during late adulthood stage. Signs of this familial dilated cardiomyopathy include:
- Arrhythmia or irregular heartbeat
- Dyspnea or shortness of breath
- Extreme tiredness called as fatigue, fainting episodes called as syncope
- Swelling of your legs and feet.
In few cases, the first symptom of this kind of disorder is a sudden cardiac death. The seriousness of the condition differs among affected ones, even in some members belonging to a same family.
What Genetic Changes Can Cause Cardiomyopathy?
According to research, it is to be estimated that around 750,000 people in the United States (U.S.) has a frequency to have dilated cardiomyopathy; means almost half of these type cases are familial kind.
In terms of Genetic Changes, Mutations happening in more than thirty genes have been discovered to be a cause for familial dilated cardiomyopathy. These kinds of genes provide sets of instructions for developing proteins, which are found in your cardiac muscle cells which is also called cardiomyocytes.
Many of these kinds of proteins play crucial roles in contraction of your cardiac muscle via their association with some cell structures,which is otherwise called sarcomeres. Sarcomeres are basic units for muscle contraction and they are made out of a protein which generates some kind of mechanical force, which is needed for your muscles to contract. Many other proteins like that which are associated with this familial dilated cardiomyopathy make up a structural framework, known as the cytoskeleton of the cardiomyocytes and the rest of the proteins play different kinds of roles within their cardiomyocytes to ensure proper functioning.
It is not clear about how mutations in these other genes can result into familial dilated cardiomyopathy but it is mostly to be seen that these changes impair cardiomyocyte functions and also reduces the abilities of these cells for contracting, weakening and thinning of cardiac muscle.
Familial dilated cardiomyopathy is also described as a nonsyndromic or an isolated type as it typically affects your heart only. Furthermore, dilated cardiomyopathy can happen as part of syndromes which affect other such organs and tissues in your body.
Inheritance Pattern Involved
Familial dilated cardiomyopathy has several inheritance patterns which depend on the genes which are involved. Familial dilated cardiomyopathy for about 80% to 90% of cases is inherited in a pattern. The pattern is known as autosomal dominant pattern where one copy of an altered gene in each cell is enough to cause a disorder. In several cases, a patient inherits such mutation from the affected parent.
Additionally, some who inherits the altered gene can never develop characteristics of familial dilated cardiomyopathy and this kind of situation is known as as reduced penetrance. Also in very rare situations, this kind is inherited as an autosomal recessive pattern that means both the copies of gene in each cell will have mutations. The parents of the patient having an autosomal recessive condition each will carry a copy of such mutated gene, but they strangely don’t show any signs and symptoms.