Transforming patient care and saving lives
Timely detection and diagnosis of cardiac disorders can identify the best treatment options and improve prognosis.
Genetic tests for cardiovascular indications
Huge progress has been made in the identification of genes involved in the etiology of hereditary cardiovascular diseases. As examples, genetic mutations have been identified in approximately two thirds of cases of hypertrophic cardiomyopathy, almost the same number in cases of dilated cardiomyopathy and in most cases of familial cardiac arrhythmias.
Cardiomyopathies cover a wide range of diseases that manifest as a primary cardiac disorder or as a cardiomyopathy secondary to a systemic disease. Cardiomyopathy can be classified into five clinical phenotypes according to morphological and functional characteristics: hypertrophic cardiomyopathy (HCM); dilated cardiomyopathy (DCM); restrictive cardiomyopathy; Arrhythmogenic cardiomyopathy of the right ventricle (RV); and unclassified cardiomyopathy, including non-compaction of the left ventricle (LV). Hypertrophic cardiomyopathy has an estimated prevalence of approximately 1: 500; dilated has a prevalence of 1: 2,500; and Arrhythmogenic myocardiopathy of the right ventricle 1: 1,000-5,000. Genetic tests in the diagnostic evaluation of patients with cardiomyopathy allow the identification of causal variants in more than 70% of children1. Cardiomyopathy can also be a presenting characteristic of other inherited disorders, such as Danon's disease, Fabry's disease, mitochondrial myopathy or muscular dystrophy. Hereditary cardiomyopathy can be inherited in an autosomal dominant, autosomal recessive, X-linked or mitochondrial manner. Rare variants in> 30 genes, some also involved in muscular dystrophy or syndromic diseases, affect a diverse set of myocardial proteins important to produce a final cardiomyopathy phenotype.
Cardiac arrhythmias can lead to syncope, cardiac arrest and sudden death. They occur in isolation or as part of another heart disease, for example, cardiomyopathies. Some of the most frequent cardiac arrhythmias are long / short QT syndrome, Brugada syndrome and atrial fibrillation. They are inherited mainly in an autosomal dominant manner, with de novo mutations that occur in some cases.
Aortic aneurysms and related diseases are characterized by the appearance of dilatations, aneurysms and dissections that occur in the aorta or in any of the main branches of the arterial tree. In general, they are classified into syndromic and non-syndromic forms (aneurysms and familial thoracic dissections, FTAAD). Syndromic forms include Marfan syndrome, Loeys-Dietz syndrome and Ehlers-Danlos syndrome2,3. Most are inherited as autosomal dominant disorders, with de novo mutations that occur in a proportion of cases. Early diagnosis is relevant for the timely treatment and prevention of fatal complications such as arterial dissection / rupture.
Congenital heart disease (CHD) accounts for approximately 1% of all live births per year and the prevalence is increasing. About 25% of all newborns affected with congenital heart disease have a critical or life-threatening condition and need surgical treatment or other treatment immediately. The majority of coronary heart diseases have a multifactorial etiology, which has complicated the identification of the contributing genes4. Congenital malformations of the heart occur in several genetic syndromes that reflect the multiple genes involved in the development of the cardiovascular system (syndromic CHD). Noonan syndrome, Alagille syndrome and Holt-Oram syndrome are known examples.
Reasons for Reference
Individuals presenting the most common symptoms of cardiovascular disease.
People with a positive family history of cardiovascular disease or sudden death (unexplained).
Individuals without a positive family history but with symptoms that resemble the indication of a specific disease.
Individuals with a negative family history, but suspicious, to perform genetic counseling.
The four main categories of genetic cardiovascular disease with some examples found regularly.