MedlinePlus Genetics :
43
Ankyrin-B syndrome is associated with a variety of heart problems related to disruption of the heart's normal rhythm (arrhythmia). Heart rhythm is controlled by electrical signals that move through the heart in a highly coordinated way. In ankyrin-B syndrome, disruption of different steps of electrical signaling can lead to arrhythmia, and the resulting heart problems vary among affected individuals.Individuals with ankyrin-B syndrome may have problems with the sinoatrial (SA) node, which generates the electrical impulses that start each heartbeat. If the SA node is not functioning properly, the heartbeat can be too slow (bradycardia). In a small number of people with ankyrin-B syndrome, the heart takes longer than usual to recharge between beats, which is known as a prolonged QT interval (long QT). Some affected individuals have impaired progression (conduction) of electrical impulses between the chambers of the heart, which can cause a problem called heart block. Other heart problems that occur in ankyrin-B syndrome include irregular and uncoordinated electrical activity in the heart's upper chambers (atrial fibrillation) or lower chambers (ventricular fibrillation) and an abnormality called catecholaminergic polymorphic ventricular tachycardia (CPVT), in which an increase in the heart rate can trigger an abnormally fast and irregular heartbeat called ventricular tachycardia. In people with ankyrin-B syndrome, arrhythmia can lead to fainting (syncope) or cardiac arrest and sudden death.When associated with a prolonged QT interval, the condition is sometimes classified as long QT syndrome 4. However, because additional heart problems can result from changes in the same gene, long QT syndrome 4 is usually considered part of ankyrin-B syndrome.
MalaCards based summary :
Cardiac Arrhythmia, Ankyrin-B-Related, also known as
long qt syndrome 4, is related to
sick sinus syndrome and
syncope, and has symptoms including
syncope An important gene associated with Cardiac Arrhythmia, Ankyrin-B-Related is
ANK2 (Ankyrin 2), and among its related pathways/superpathways are
Developmental Biology and
Transmission across Chemical Synapses. Affiliated tissues include
heart, and related phenotypes are
sudden cardiac death and
prolonged qt interval
Disease Ontology :
12
A long QT syndrome that has material basis in heterozygous mutation in ANK2 on chromosome 4q25-q26.
OMIM® :
57
Loss-of-function mutations in ANK2 can result in a broad spectrum of clinical cardiac phenotypes. Carriers of some mutations (e.g., E1425G, 106410.0001) display QT interval prolongation, stress- and/or exercise-induced polymorphic ventricular arrhythmia, syncope, and sudden cardiac death. Patients with other variants show clinical phenotypes, sometimes mild, extending beyond LQTS, leading to the label 'ankyrin-B syndrome.' These phenotypes include bradycardia, sinus arrhythmia, delayed conduction/conduction block, idiopathic ventricular fibrillation, and catecholaminergic polymorphic ventricular tachycardia (Mohler et al., 2007).
(600919) (Updated 05-Mar-2021)
UniProtKB/Swiss-Prot :
73
Long QT syndrome 4: A heart disorder characterized by a prolonged QT interval on the ECG and polymorphic ventricular arrhythmias. They cause syncope and sudden death in response to exercise or emotional stress, and can present with a sentinel event of sudden cardiac death in infancy. Long QT syndrome type 4 shows many atypical features compared to classical long QT syndromes, including pronounced sinus bradycardia, polyphasic T waves and atrial fibrillation. Cardiac repolarization defects may be not as severe as in classical LQT syndromes and prolonged QT interval on EKG is not a consistent feature.
