Chronic Obstructive Pulmonary Disease and Cardiac Repolarization: Data from a Randomized Controlled Trial

Abstract

Background: Altered cardiac repolarization is a risk factor for sudden cardiac death and seems to be increased in chronic obstructive pulmonary disease (COPD) patients. Objective: Lung volume reduction surgery (LVRS) has been shown to improve breathing mechanics and lung function in patients with severe COPD and emphysema and possibly also improve altered cardiac repolarization. Methods: Thirty patients scheduled for LVRS were randomized to LVRS or to the control group. We investigated the treatment effect 3 months after LVRS on measures of cardiac repolarization and dispersion of repolarization (QTc interval, QT dispersion) derived from electrocardiography. Univariable and multivariable analyses were used to identify possible confounders influencing the treatment effect. Results: LVRSwas associated with an improvement in lung function (mean ± SD residual volume/total lung capacity of -9 ± 11% and forced expiratory volume in 1 s of +30 ± 29%). LVRS did not significantly reduce QTc (median -5.3 ms, 95% confidence interval, CI -15.5 to 3.7, p = 0.214) and QT dispersion (median -3.0 ms, 95% CI -13.0 to 7.0, p = 0.536) compared to the control group. No significant association between change in QTc and change in QT dispersion, respectively, and change in possible confounders was found. Conclusion: LVRS seems to have no effect on cardiac repolarization in patients with COPD. Thus, lung hyperinflation seems not to be a causal mechanism for altered cardiac repolarization in COPD patients.

The relationship between frontal QRS‐T angle and the severity of newly diagnosed chronic obstructive pulmonary disease

“…Thus, the increased risk of mortality F I G U R E 1 An example of the calculation of frontal QRS-T angle using the automatic report of the ECG device as a result of cardiovascular causes in these patients has been principally attributed to cardiac arrhythmias and SCD because of the altered cardiac repolarization and depolarization. [2][3][4][5]16 Although the main mechanism of the altered cardiac repolarization and depolarization in patients with COPD has not been clearly elucidated, it has been suggested that hypoxemia, autonomic dysfunction and acidbase disturbances might be the potential causes. 6,8,17 Alteration in myocardial repolarization represents an increased risk for malign cardiac arrhythmia and SCD.…”

The Role of Electrocardiographic Markers in the Prevention of Atrial and Ventricular Arrhythmias

“…In nearly 75% of patients with paroxysmal, AF has an increased duration of the initial portion of P wave in lead III [24]. Various investigations have reported the clinical value of P-wave measurements in the prediction of AF ( Table 2) [22,23,[25][26][27][28][29][30].…”

“…Hyperthyroidism [25,26] Postcardiac surgery [27,28] Renal failure and renal replacement therapy [22,23] Pulmonary diseases [29,30]…”