INTRODUCTION
Chronic Obstructive Pulmonary Disease (COPD), which is characterized by
persistent airflow restriction and respiratory symptoms, is one of the
most common causes of death globally 1. Previous
studies have demonstrated that COPD patients are at increased risk of
cardiovascular morbidity and mortality 2–4. Cardiac
arrhythmias and sudden cardiac death (SCD) are very common in these
patients 3,5. The underlying mechanism of the
relationships among COPD, cardiac arrhythmias, and SCD has not been
clearly elucidated yet. Nevertheless, hypoxemia, autonomic dysfunction
and acid-base disturbances can causes the improving of cardiac
arrhythmias and SCD by altering myocardial repolarization in these
patients 6.
Alteration in myocardial repolarization has a crucial role in improving
cardiac arrhythmias and SCD 7,8. Frontal QRS-T angle,
which is a novel marker of the heterogeneity in myocardial
depolarization and repolarization, is described as the absolute
difference between myocardial depolarization (QRS- axis) and
repolarization (T axis) 9. It can easily be measured
by using the 12-lead surface electrocardiography (ECG), and its
abnormality reflects the electrical instability of the myocardium10. The frontal QRS-T angle has been shown to be
valuable in predicting many cardiac and non-cardiac diseases11.
To our knowledge, there is no research that investigated the
relationship between the frontal QRS-T angle and the severity of COPD.
Our objective in this study is to evaluate the relationship between the
frontal QRS-T angle and the severity of recently diagnosed COPD.