Clinical Associations between Serial Electrocardiography Measurements and Sudden Cardiac Death in Patients with End-Stage Renal Disease Undergoing Hemodialysis

Preexisting hemodialysis and survival outcome in out-of-hospital cardiac arrest patients: Ulsan, South Korea

Background

Although the incidence of sudden cardiac death is higher in hemodialysis (HD) patients, whether out-of-hospital cardiac arrest (OHCA) survival outcomes are poorer in this group remains unclear. This study aimed to assess the impact of HD on survival outcomes among adult nontraumatic OHCA patients and to compare these outcomes between HD and non-HD groups.

Methods

This observational cohort study retrospectively analyzed data from adult nontraumatic OHCA patients in Ulsan, South Korea, from January 2017 through December 2022. Multivariable logistic regression analysis was applied to evaluate whether HD was a risk factor for survival in OHCA patients. Survival was compared between the two groups in unadjusted, balanced groups by propensity score matching (PSM) and inverse probability of the treatment weighting (IPWT).

Results

The study included 2,489 patients (64 HD group and 2,425 non-HD group). Undergoing HD was not significantly associated with any return of spontaneous circulation (ROSC) (adjusted odds ratio [95% confidence interval], p-value, 1.648 [0.934-2.907], 0.085), survival to discharge (1.544 [0.734-3.250], 0.252), or neurological outcomes (0.394 [0.017-9.346], 0.564). There were also no significant differences observed in any ROSC (1.648 [0.934-2.907], 0.085), survival to discharge (1.544 [0.734-3.250], 0.252), or favorable neurological outcome (0.394 [0.017-9.346], 0.564) between the two unadjusted groups. The insignificant survival differences were persistently observed in the PSM group and IPWT group.

Conclusion

Although HD may pose a risk factor for cardiac arrest, our study did not find a significant association with survival outcomes in OHCA patients. Additionally, no notable survival difference was observed between HD and non-HD groups. Therefore, resuscitation efforts in HD patients should not be underestimated.

Clinical implication of electrocardiogram change in patients experiencing lung transplantation with end stage lung disease

Introduction

End-stage lung disease causes cardiac remodeling and induces electrocardiogram (ECG) changes. On the other way, whether lung transplantation (LTx) in end-stage lung disease patients are associated with ECG change is unknown. The object of this study was to investigate ECG changes before and after LTx in end-stage lung disease patients and whether these changes had clinical significance.

Method

This was a single-center retrospective cohort study of 280 end-stage lung disease patients who consecutively underwent LTx at a tertiary referral hospital. ECG findings before LTx and within 1 week and 1, 3, and 6 months after LTx were obtained and analyzed. To find clinical meaning, the ECG at 1 month after LTx was analyzed according to 1-year survival (survivor vs non-survivor groups). Survival data were estimated using the Kaplan-Meier method.

Results

Significant differences were observed in the PR interval, QRS duration, QT interval, QTc interval, and heart rate before LTx and 1 month after LTx; the PR interval, QRS duration, QTc interval, and heart rate were decreased. Particularly, the QTc interval was significantly decreased 1 month after LTx, whereas there was no significant change in the QTc interval from 1 to 6 months thereafter. The PR interval, QT interval, QTc interval, and heart rate were significantly different between the survivor and non-survivor groups. The serial changes in QTc interval before LTx and 1 and 3 months after LTx were also significantly different between the survivor and non-survivor groups (p = 0.040 after adjusting for age and body mass index). Upon dividing the patients based on the range of QTc interval change ≤ -8 ms, >-8-10 ms, >10-35 ms, >35 ms), the survival rate was significantly lower in the group whose QTc interval at 1 month after LTx decreased by > 35 m (p = 0.019).

Conclusion

LTx in patients with end-stage lung disease may induce ECG changes. Patients whose QTc interval at 1 month after LTx decreased by > 35 ms have a significantly higher 1-year mortality rate. Hence, these ECG changes may have clinical and prognostic significance.

Impact of Electrocardiographic Parameters on Sudden Death in Patients Receiving Maintenance Hemodialysis: Ten-Year Outcomes of the Q-Cohort Study

AIM

Sudden death is one of the most common causes of death among hemodialysis patients. Electrocardiography (ECG) is a noninvasive and inexpensive test that is regularly performed in hemodialysis clinics. However, the association between abnormal ECG findings and the risk of sudden death in hemodialysis patients is yet to be fully elucidated. Thus, the aim of this study was to determine the ECG parameters linked to sudden death in patients undergoing hemodialysis.

METHODS

The Q-Cohort Study is a multicenter, longitudinal, observational study of hemodialysis patients. In this study, 1,153 Japanese hemodialysis patients aged ≥ 18 years with ECG data recorded within 1 year of study enrollment were followed up for 10 years. Cox proportional hazards models were used to estimate the multivariate-adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for the association between ECG parameters and sudden death.

RESULTS

During the median follow-up period of 9.0 years, 517 patients died, 76 of whom exhibited sudden death. After adjusting for confounding factors, higher heart rate, QT prolongation, and left ventricular hypertrophy as per the Sokolow-Lyon voltage criteria were found to be independently associated with an increased risk of sudden death. The adjusted HRs [95% CIs] for each abnormal ECG parameter were 2.02 [1.05-3.89], 2.10 [1.30-1.77], and 1.91 [1.18-3.09], respectively.

CONCLUSIONS

Higher heart rate, QT prolongation, and left ventricular hypertrophy on ECG have been determined to be associated with an increased risk of sudden death. Therefore, regular ECG recording could enable medical practitioners to identify hemodialysis patients who require intervention to prevent lethal arrhythmia.