Cardiovascular considerations in tuberous sclerosis
Joanna Kohut1, Bogusław Mazurek1, Jacek Pająk1, Lesław Szydłowski1, Aleksandra Morka2
Tuberous sclerosis complex is a genetic condition with an autosomal dominant pattern of inheritance, with an incidence of approximately 1:10,000, and 1:6,800 in the paediatric population, caused by a mutation of either of two genes: TSC1 on chromosome 9 (9q34) or TSC2 on chromosome 16 (16p13.3). Detailed American guidelines for cardiologists published in 2014 emphasize the vast assortment of phenotypes that may be found on tuberous sclerosis complex spectrum. The condition may manifest either very early, with foetal cardiac rhabdomyomas, observed as early as at 15 weeks of gestation, or with cardiovascular symptoms (aberrant cardiac conduction in particular) in adult tuberous sclerosis complex patients with no previous history of any such symptoms. Cardiovascular manifestations in tuberous sclerosis complex patients, apart from rhabdomyomas, arrhythmia and conduction disorders, include also rarer symptoms, such as coarctation of the aorta, thoracic or abdominal aortic aneurysms, rhabdomyositis (a rare form of cardiomyopathy), and hypertension. Echocardiography is the method of choice in the diagnosis of cardiac involvement in the course of tuberous sclerosis complex. Rhabdomyomas tend to occur between 20 and 30 weeks of foetal life. Cardiac magnetic resonance imaging can be used an alternative, and sometimes as a useful adjunct to echocardiography in the diagnostic workup of tuberous sclerosis complex. In the past 5 years, there have been some reports regarding the use of everolimus to induce prompt regression of rhabdomyomas in cases of heart failure resistant to conventional pharmacotherapy. The natural history of a vast majority of rhabdomyomas, however, is spontaneous regression within the child’s first year of life. In isolated cases, cardiac surgery is required to excise the tumours causing refractory heart failure.