Short‐period temporal repolarization dispersion in subjects with atrial fibrillation and decompensated heart failure

Abstract

Background/objectives The association between chronic heart failure (CHF) and permanent atrial fibrillation is very frequent. The repolarization duration was already found predictive for atrial fibrillation. Aim of this study was to evaluate the influence of atrial fibrillation on short period repolarization variables in decompensated CHF patients. Method We used 5 min ECG recordings to assess the mean, standard deviation (SD), and normalized variance (NV) of the following variables: QT end (QTe), QT peak (QTp), and T peak to T end (Te) in 121 decompensated CHF, of whom 40 had permanent atrial fibrillation, too. We reported also the 30‐day mortality. Results QTpSD (p < .01), TeSD (p < .01), QTpVN (p < .01), and TeVN (p < .01) were higher in the atrial fibrillation than among sinus rhythm CHF subjects. Multivariable logistic analysis selected only TeSD (odd ratio, o.r.: 1.32, 95% confidence interval, c.i.: 1.06–1.65, p: .015) associated with atrial fibrillation. A total of 27 patients died during the 30‐days follow‐up (overall mortality rate 22%), 7 (18%), and 20 (25%) respectively in the atrial fibrillation and sinus rhythm patients. Furthermore, the following variables were associated to the morality risk: NT‐pro Brain Natriuretic Peptide (o.r.: 1.00, 95% c.i.: 1.00–1.00, p: .041), left ventricular end diastolic diameter (o.r.: 0.81, 95% c.i.: 0.67–0.96, p: .010), and Te mean (o.r.: 1.04, 95% c.i.: 1.02–1.09, p: .012). Conclusion In decompensated CHF subjects, Te mean seems be associated to mortality and TeSD to the permanent atrial fibrillation. We could hypothesize that, during severe CHF, the multi‐level ionic CHF channel derangement could be critical in influencing these non‐invasive markers. (ClinicalTrials.gov number, NCT04127162).

Glucose dysregulation and repolarization variability markers are short-term mortality predictors in decompensated heart failure

“…For these reasons, we believe that elevated fasting glucose level and an increase of Te mean could be also considered a simple noninvasive marker of short-period mortality in acutely decompensated patients. In previous studies, both fasting glucose [16] and Te mean [4–6] were significantly associated with short-period mortality in this kind of CHF subjects; the novelty of the present study was the evidence that these two studied variables mutually increased their predictive power. Whereas we do not know if these two variables are merely mortality risk markers or if they even have a causal role, however, the link between these two variables should be sought in the combination of frequent diabetes complications and pathophysiological CHF derangement.…”

“…In particular, the II ECG lead recordings, the same used in our study, could represent a marker of apicobasal and interventricular repolarization myocardial dispersion rather than transmural [24]. However, whatever the genesis of this parameter could be, Te remains a powerful predictive marker of total and cardiovascular mortality [4–8] and not a mere marker of sudden cardiac death.…”

“…We, therefore, calculated mean (QT mean and Te mean), variance and SD (QT SD and Te SD ) values for each of these repolarization phase intervals, and finally, we calculated the variance normalized for mean of QT (QTVN) and Te (TeVN) [ 4 , 14 , 15 ].…”

“…could be used to stratify the 30-day mortality risk in decompensated CHF subjects. In particular, we recently observed that an increase of Tpeak-Tend interval (Te), obtained during 5-min ECG recoding, was able to stratify the short-period mortality risk in this kind of patients [4][5][6]. Previously, in a meta-analysis based on patients with different cardiovascular risk profiles [7] and in a large longitudinal epidemiologic study [8], an increased risk of cardiovascular mortality, sudden arrhythmic death and total mortality associated with a Te increase were reported.…”

Periodic repolarization dynamics as predictor of risk for sudden cardiac death in chronic heart failure patients

“…Several works have proposed other markers related to repolarization variability measured from short-term ECG recordings, such as the variance normalized by the mean of QT end, QT peak or T-peak-to-T-end (Te) intervals, and have evaluated them in CHF populations. In recent studies, the mean and/or standard deviation of Te have been shown to predict 30-day mortality 58 , 59 and mortality in hospital 60 among decompensated CHF patients.…”