LONDON — Inherited cardiac conditions such as heart muscle or rhythm problems may be well known within families or only discovered after a family member dies unexpectedly. To detect and treat these diseases, Mayo Clinic Healthcare in London is adding inherited cardiac condition services including advanced imaging and electrocardiography (ECG) and genetic testing and counseling.
Inherited cardiac conditions affect people of all ages and ethnicities, says Elijah Behr, M.D., a cardiologist at Mayo Clinic Healthcare. Improvements in cardiac imaging and ECG technology and the development of genetic screening and genetic counseling are helping physicians and families work together to identify and manage the conditions.
“An inherited cardiac condition is a disease affecting the heart that is caused by genetic problems. These are misspellings of the genetic code, known as DNA, and are often called mutations,” Dr. Behr says. “Mutations can be inherited from parents or, if it is a sporadic mutation, occur for the first time in a specific family member.”
Those who carry the mutation may be at risk from complications of heart disease, including heart rhythm problems, or arrhythmias; heart failure; and strokes. Many people will not have symptoms, but some may experience palpitations, blackouts, breathlessness or chest pain.
“If a family member has died suddenly and unexpectedly at a young age, it is possible that genetic heart disease is the cause. This means that other family members may be at risk,” Dr. Behr says. “Expert evaluation of cases of sudden death and family members is an important way to try to prevent further deaths.”
Major types of heart conditions that may be genetic include:
- Cardiomyopathies: heart muscle diseases such as hypertrophic cardiomyopathy, heart muscle thickening that makes it harder for the heart to pump blood; dilated cardiomyopathy, where an enlarged left ventricle prevents effective pumping of blood; and arrhythmogenic cardiomyopathy, where replacement of the right and sometimes left ventricle by scar and fat tissue leads to heart rhythm problems.
- Channelopathies or arrhythmias: diseases of the heart’s electrical function that can cause fast, chaotic heartbeats leading to blackouts and cardiac arrest. Those include long QT syndrome, Brugada syndrome, and early repolarization syndrome;CPVT, or catecholaminergic polymorphic ventricular tachycardia, which can cause a dangerously fast heart rhythm during exercise; and idiopathic ventricular fibrillation.
- Premature coronary artery diseaseusually due to high cholesterol levels due to problems with how the body processes cholesterol, known as familial hypercholesterolemia.
- Unexpected sudden deaths, some of which may be unexplained and known as sudden arrhythmic death syndrome (SADS), often are caused by genetic conditions, especially in young people. This means that their family members may carry heart disease
Genetic counseling is an important part of care; genetic counselors help families understand genetic testing and its implications. Sometimes family members come to the clinic together for testing and counseling.
“Sometimes there can be a taboo or anxiety around discussing inherited medical conditions within families,” Dr. Behr says. “Genetic counselors help break these barriers by having that conversation.”
At Mayo Clinic Healthcare, located at 15 Portland Place in the Harley Street Medical Area, care is tailored to each person. Patients will have an initial interview with a cardiac genetic nurse or counselor followed by a focused evaluation by the cardiologist. Tests can be arranged for one day, prior to the doctor’s assessment and at the patient’s convenience. If genetic testing is required, a genetic counselor will help to move it forward.
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