Brugada syndrome
In the western world it affects mainly young and middle-aged adult men. It has been associated with mutations in the same sodium channel that is affected in long QT syndrome, but this appears to account for only 1 in every 5 people with the condition. The sodium channel behaves abnormally in that movement of sodium ions into the cells is restricted. This results in particular changes on the ECG but no abnormalities in the structure of the heart. Other genes have been described as being involved in Brugada syndrome that produce calcium ion channels and a protein in the cell surface (membrane) that interacts with the sodium channel. They have, however, only been detected in a small number of carriers.
Coronary artery anomalies
The heart is a muscle and requires a regular supply of oxygen and nutrients to function. This is supplied by blood carried by two blood vessels known as the left and right coronary arteries. The arteries arise from the left and right side of the body’s main artery, the aorta. In up to 1% of […]
Catecholaminergic polymorphic ventricular tachycardia (CPVT)
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare condition that has been associated with two genes that make proteins found inside the cell – the human ryanodine receptor (a calcium ion channel) and calsequestrin (a protein that interacts with the calcium channel). These regulate the release of calcium ions into the rest of the cell. […]
Dilated cardiomyopathy (DCM)
In dilated cardiomyopathy (DCM) the main pumping chambers of the heart are dilated and contract poorly. This results in a reduced volume of blood (low output) pumped around the body which fails to meet the body’s demand and features of what is commonly known as heart failure. There is a build up of fluid in […]
Long QT syndrome (LQTS)
Long QT syndrome (LQTS) is an ion channelopathy. Ion channelopathies (also sometimes referred to as arrhythmia syndromes or cardiac channelopathies)affect the electrical functioning of the heart without affecting the heart’s structure. They are a group of rare genetic conditions that are caused by abnormalities of the DNA known as mutations. They are usually inherited from parents although they can occur for the first time in a person. (If they occur for the first time they are described as sporadic.)
Progressive cardiac conduction defect (PCCD)
Progressive cardiac conduction defect (PCCD) is a rare condition. In people with PCCD, the heart’s electrical impulses are conducted very slowly and this results in the gradual development over time of heart block. (Heart block is a failure of the heart’s electrical impulse to conduct properly from the top chambers [the atria] to the bottom […]