The Relationship Between the Mutation of Cardiac Potassium-Channel and Early Repolarization and the Importance of the Arrhythmia Marker Tests in this Population
Öz
Aim
Early repolarization (ER) electrocardiographic pattern is not
rare in the general population. This electrocardiographic (ECG)
abnormality, which has been accepted as benign for years, has
attracted attention with its association with sudden cardiac
death (SCD). The association of fatal arrhythmia history and
this pattern of ECG is defined as ER syndrome (ERS). Several
tests can help clinicians to understand which ER patterns cause a
risk for malignant arrhythmias. As in the other channelopathies,
ion channel-related gene mutations have also been reported in
ERS. In this study, we investigated the presence of the mutation
in KCNJ8, which has been described for the first time in ERS in
the groups with and without ER and which leads to an electrical functional change in the potassium (K) channel, causing an
arrhythmia. In addition, we attempted to determine the risk for
arrhythmia with 24-hour ECG monitoring and signal-averaged
electrocardiogram (SAECG).
Materials and Methods
A total of 100 patients who met the ECG criteria, and 50 of
whom had ER patterns underwent rhythm Holter evaluations.
The presence of SAECG and late potentials (LP) were studied. KCNJ8 gene mutation was investigated with the Polymerase
Chain Reaction (PCR) method.
Results
The majority of the patients in the ER pattern group were in
ER type 1 pattern. Although not statistically significant, QTc
intervals were shorter in the ER group. There were no significant ventricular arrhythmias in rhythm Holter records in both
groups. Heart rate variability (HRV) was decreased by 26%, and
late potentials (LP) were found in 14% of the patients in this
group with SAECG. No correlation was found between the investigated KCNJ8-S422L genetic mutation and ER pattern.
Conclusion
At the end of the study, the investigated genetic mutation was
observed in the control group, and not in the ER group. This
can be explained by the fact that the majority of the patients in
the ER group were asymptomatic for cardiac symptoms, and
they had no family history of SCD. Furthermore, comprehensive studies with a larger population of patients at risk will shed
light on the importance of arrhythmic tests and possible gene
mutation.
Anahtar Kelimeler
Kaynakça
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