Assessment of arrhythmias and cardiac autonomic tone at a relatively young age patients with obesity class III

The association between insulin resistance and QT interval: A systematic review and Meta-Analysis

BACKGROUND

Insulin resistance (IR) is a major health concern associated with various diseases, and prolonged QT interval can potentially lead to life-threatening arrhythmias and death. There are conflicting views on the relationship between IR and QT interval. This meta-analysis aims to comprehensively investigate the association between IR and QT interval.

METHODS

An extensive search in databases PubMed, Scopus, Cochrane Library, Embase, and Web of Science up to October 2024 was conducted. Cohort studies which reported means and standard deviations for the QTc interval across the case and control groups with and without insulin resistance based on HOMA-IR were eligible for inclusion. Research with partial or inaccessible primary data, those involving participants with pre-existing cardiac conditions, and those with ambiguous results were excluded. The evaluation of study quality utilized the Newcastle-Ottawa Scale. A random-effects model was applied for the meta-analysis, and Egger's test was used to assess publication bias. GRADEproGDT was used to evaluate the certainty of the evidence.

RESULTS

Five studies, encompassing 603 participants, met the inclusion criteria. A significant positive association was observed between IR and QT interval (Weighted Mean Difference [WMD] = 12.38, 95% Confidence Interval [CI]: 5.51, 19.25). All included studies demonstrated high methodological quality. Assessment for publication bias revealed no significant findings (p-value for Egger's test = 0.39). The quality of evidence for the main outcome was moderate. Subgroup analyses revealed a significant link between IR and QT interval in studies from Turkey and India, with samples over fifty, and involving adults.

CONCLUSIONS

This meta-analysis highlights that IR is linked to an elevated risk of QT prolongation. Early identification of IR is crucial to mitigate the risk of QT prolongation and subsequent arrhythmias, thus emphasizing the importance of early intervention to prevent adverse cardiac outcomes and sudden cardiac death. Caution is needed when interpreting our results due to study heterogeneity, certainty of evidence, and sensitivity analysis findings. More rigorous research on this subject is required.

Bariatric surgery partially reverses subclinical proarrhythmic structural, electrophysiological, and autonomic changes in obesity

BACKGROUND

Obesity confers higher risks of cardiac arrhythmias. The extent to which weight loss reverses subclinical proarrhythmic adaptations in arrhythmia-free obese individuals is unknown.

OBJECTIVE

The purpose of this study was to study structural, electrophysiological, and autonomic remodeling in arrhythmia-free obese patients and their reversibility with bariatric surgery using electrocardiographic imaging (ECGi).

METHODS

Sixteen arrhythmia-free obese patients (mean age 43 ± 12 years; 13 (81%) female participants; BMI 46.7 ± 5.5 kg/m2) had ECGi pre-bariatric surgery, of whom 12 (75%) had ECGi postsurgery (BMI 36.8 ± 6.5 kg/m2). Sixteen age- and sex-matched lean healthy individuals (mean age 42 ± 11 years; BMI 22.8 ± 2.6 kg/m2) acted as controls and had ECGi only once.

RESULTS

Obesity was associated with structural (increased epicardial fat volumes and left ventricular mass), autonomic (blunted heart rate variability), and electrophysiological (slower atrial conduction and steeper ventricular repolarization time gradients) remodeling. After bariatric surgery, there was partial structural reverse remodeling, with a reduction in epicardial fat volumes (68.7 cm3 vs 64.5 cm3; P = .0010) and left ventricular mass (33 g/m2.7 vs 25 g/m2.7; P < .0005). There was also partial electrophysiological reverse remodeling with a reduction in mean spatial ventricular repolarization gradients (26 mm/ms vs 19 mm/ms; P = .0009), although atrial activation remained prolonged. Heart rate variability, quantified by standard deviation of successive differences in R-R intervals, was also partially improved after bariatric surgery (18.7 ms vs 25.9 ms; P = .017). Computational modeling showed that presurgical obese hearts had a larger window of vulnerability to unidirectional block and had an earlier spiral-wave breakup with more complex reentry patterns than did postsurgery counterparts.

CONCLUSION

Obesity is associated with adverse electrophysiological, structural, and autonomic remodeling that is partially reversed after bariatric surgery. These data have important implications for bariatric surgery weight thresholds and weight loss strategies.

The Prevalence of Arrhythmias, Including Premature Supraventricular and Ventricular Beats and Other Electrocardiographic Patterns, in 24-Hour Holter Monitoring in Patients with Overweight and Obesity

OBJECTIVES

this study aims to evaluate the prevalence of various arrhythmias and other electrocardiographic patterns within the group of individuals with overweight and obesity.

METHODS

One hundred eighty-one adults (90 females and 91 males) were qualified for inclusion in the experimental group. All participants had a body mass index (BMI) exceeding 25 kg/m2 (98 patients with obesity and 83 with overweight). The mean BMI in the obesity group was 33.6 kg/m2, and all participants had class 1 obesity. The control group comprised 69 individuals (56 females and 13 males) with normal BMI. The basic measurements were performed, and the participants filled out questionnaires describing their health conditions and lifestyles. Each participant underwent an electrocardiographic (ECG) examination and a 24 h Holter ECG examination.

RESULTS

In patients with class 1 obesity compared to the control patients, the average numbers of premature ventricular beats (PVBs) and premature supraventricular beats (SPBs) were statistically significantly higher (p = 0.030 and p = 0.042). There was a positive correlation between body weight and PVB (p = 0.028) and between body weight and SPB (p = 0.028). Moreover, BMI and waist circumference were correlated with SPB (p = 0.043 and p = 0.031). In the backward stepwise multivariate regression model considering 24 h Holter ECG monitoring, concerning SPB as the dependent variable, it was observed that BMI (especially obesity class 1), type 2 diabetes, and thyroid disease exhibited the highest regression coefficients.

CONCLUSIONS

obesity, even in class 1, might be a factor in a more frequent occurrence of abnormalities in electrocardiographic tests.

Holter-Derived Autonomic Function, Arrhythmias and Carbohydrate Metabolism in Patients with Class III Obesity Treated with Laparoscopic Sleeve Gastrectomy

The effects of weight loss following bariatric surgery on autonomic balance, arrhythmias and insulin resistance are still of interest. We prospectively investigated 50 patients with BMI > 40 kg/m², aged 36.5 (18–56) years who underwent laparoscopic sleeve gastrectomy. Among other examinations, all subjects had 24-h Holter monitoring with heart rate variability (HRV) and heart rate turbulence (HRT) evaluation. After a median of 15 months, BMI decreased from 43.9 to 29.7 kg/m², the incidence of hypertension decreased from 54 to 32% (p = 0.04) and any carbohydrate disorders decreased from 24 to 6% (p = 0.02). Fasting insulin concentration and insulin resistance index improved significantly (p < 0.001). Improvements in HRV parameters related to the sympathetic autonomic division were also observed (p < 0.001), while HRT evaluation was not conclusive. The enhancement of autonomic tone indices was correlated with reduction of BMI (SDNN-I r = 0.281 p = 0.04; SDNN r = 0.267 p = 0.05), but not with reduction of waist circumference, and it was also associated with decrease of mean heart rate (OR 0.02, 95%CI 0.0–0.1, p < 0.001). The incidence of arrhythmias was low and similar before and after follow-up. In conclusion, improvement of homeostasis of carbohydrate metabolism and autonomic function is observed in relatively young patients after weight loss due to laparoscopic sleeve gastrectomy.