Arrhythmias in Patients on Maintenance Dialysis: A Cross-sectional Study.

RATIONALE & OBJECTIVE: Patients with kidney failure treated with maintenance dialysis experience a high rate of mortality, in part due to sudden cardiac death caused by arrhythmias. The prevalence of arrhythmias, including the subset that are clinically significant, is not well known. This study sought to estimate the prevalence of arrhythmias, characterize the pattern of arrhythmic events in relation to dialysis treatments, and identify associated clinical characteristics. STUDY DESIGN: Cross-sectional study. SETTING & PARTICIPANTS: 152 patients with kidney failure treated with maintenance dialysis in Denmark. EXPOSURES: Dialysis treatment; clinical characteristics; cardiac output and preload defined using echocardiography. OUTCOMES: Prevalence and pattern of arrhythmias on 48-hour Holter monitoring; odds ratios for arrhythmias. ANALYTICAL APPROACH: Descriptive analysis of the prevalence of arrhythmias. Pattern of arrhythmias described using a repeated-measures negative binomial regression model. Associations between clinical characteristics and echocardiographic findings with arrhythmias were assessed using logistic regression. RESULTS: Among the 152 patients studied, 83.6% were treated with in-center dialysis; 10.5%, with home hemodialysis; and 5.9%, with peritoneal dialysis. Premature atrial and ventricular complexes were seen in nearly all patients and 41% had paroxysmal supraventricular tachycardia. Clinically significant arrhythmias included persistent atrial fibrillation observed among 8.6% of patients, paroxysmal atrial fibrillation among 3.9%, nonsustained ventricular tachycardia among 19.7%, bradycardia among 4.6%, advanced second-degree atrioventricular block among 1.3%, and third-degree atrioventricular block among 2.6%. Premature ventricular complexes were more common on dialysis days, while tachyarrhythmias were more often observed during dialysis and in the immediate postdialytic period. Older age (OR per 10 years older, 1.53; 95% CI, 1.15-2.03; P=0.003), elevated preload (OR, 4.02; 95% CI, 1.05-15.35; P=0.04), and lower cardiac output (OR per 1L/min greater, 0.66; 95% CI, 0.44-1.00; P=0.05) were independently associated with clinically significant arrhythmias. LIMITATIONS: Arrhythmia monitoring limited to 48 hours; small sample size; heterogeneous nature of the population, risk for residual confounding. CONCLUSIONS: Arrhythmias, including clinically significant abnormal rhythms, were common. Tachyarrhythmias were more frequent during dialysis and the immediate postdialytic period. The relevance of these findings to clinical outcomes requires additional study.

Hemodialysis Using High Cut Off Filters in Light Chain Cast Nephropathy.

BACKGROUND/AIM: Hemodialysis using high cutoff (HCO) filters possibly improves renal function in diseases with light chain (LC) overproduction and acute kidney injury. We established the effect of HCO dialysis on renal outcome in consecutive patients with malignant monoclonal gammopathies and LC cast nephropathy. METHODS: LC concentration was measured before and after each dialysis session in 10 patients receiving HCO dialysis and bortezomib-based chemotherapy, and their renal function was monitored by plasma creatinine. RESULTS: The number of HCO sessions ranged from 4 to 34 (mean 13). Six patients recovered kidney function, 3 regained partial function while 1 patient continued chronic dialysis. Patients with the largest reductions in LC during HCO treatments had the lowest creatinine at 6 and 9 months of follow-up. For comparison, only 2 out of 10 patients in a historic control group recovered kidney function. CONCLUSION: HCO dialysis combined with bortezomib results in good renal recovery with kidney function being dependent on the degree of LC lowering.

Protocol for a randomised controlled trial comparing warfarin with no oral anticoagulation in patients with atrial fibrillation on chronic dialysis: the Danish Warfarin-Dialysis (DANWARD) trial.

INTRODUCTION: Atrial fibrillation is highly prevalent in patients on chronic dialysis. It is unclear whether anticoagulant therapy for stroke prevention is beneficial in these patients. Vitamin K-antagonists (VKA) remain the predominant anticoagulant choice. Importantly, anticoagulation remains inconsistently used and a possible benefit remains untested in randomised clinical trials comparing oral anticoagulation with no treatment in patients on chronic dialysis. The Danish Warfarin-Dialysis (DANWARD) trial aims to investigate the safety and efficacy of VKAs in patients with atrial fibrillation on chronic dialysis. The hypothesis is that VKA treatment compared with no treatment is associated with stroke risk reduction and overall benefit. METHODS AND ANALYSIS: The DANWARD trial is an investigator-initiated trial at 13 Danish dialysis centres. In an open-label randomised clinical trial study design, a total of 718 patients with atrial fibrillation on chronic dialysis will be randomised in a 1:1 ratio to receive either standard dose VKA targeting an international normalised ratio of 2.0-3.0 or no oral anticoagulation. Principal analyses will compare the risk of a primary efficacy endpoint, stroke or transient ischaemic attack and a primary safety endpoint, major bleeding, in patients allocated to VKA treatment and no treatment, respectively. The first patient was randomised in October 2019. Patients will be followed until 1 year after the inclusion of the last patient. ETHICS AND DISSEMINATION: The study protocol was approved by the Regional Research Ethics Committee (journal number H-18050839) and the Danish Medicines Agency (case number 2018101877). The trial is conducted in accordance with the Helsinki declaration and standards of Good Clinical Practice. Study results will be disseminated to participating sites, at research conferences and in peer-reviewed journals. TRIAL REGISTRATION NUMBERS: NCT03862859, EUDRA-CT 2018-000484-86 and CTIS ID 2022-502500-75-00.

Renal Artery Stenting in Consecutive High-Risk Patients With Atherosclerotic Renovascular Disease: A Prospective 2-Center Cohort Study.

Background The aim of this study was to prospectively evaluate the effects of renal artery stenting in consecutive patients with severe atherosclerotic renal artery stenosis and high-risk clinical presentations as defined in a national protocol developed in 2015. Methods and Results Since the protocol was initiated, 102 patients have been referred for revascularization according to the following high-risk criteria: severe renal artery stenosis (≥70%) with true resistant hypertension, rapidly declining kidney function, or recurrent heart failure/sudden pulmonary edema. At baseline, the mean 24-hour ambulatory systolic blood pressure was 166.2 mm Hg (95% CI, 162.0-170.4), the defined daily dose of antihypertensive medication was 6.5 (95% CI, 5.8-7.3), and the estimated glomerular filtration rate was 41.1 mL/min per 1.73m2 (95% CI, 36.6-45.6). In 96 patients with available 3-month follow-up data, mean 24-hour ambulatory systolic blood pressure decreased by 19.6 mm Hg (95% CI, 15.4-23.8; P<0.001), the defined daily dose of antihypertensive medication was reduced by 52% (95% CI, 41%-62%; P<0.001), and estimated glomerular filtration rate increased by 7.8 mL/min per 1.73m2 (95% CI, 4.5-11.1; P<0.001). All changes persisted after 24 month follow-up. Among 17 patients with a history of hospitalization for acute decompensated heart failure, 14 patients had no new episodes after successful revascularization. Conclusions In this prospective cohort study, we observed a reduction in blood pressure and antihypertensive medication, an increase in estimated glomerular filtration rate, and a decrease in new hospital admissions attributable to heart failure/sudden pulmonary edema after renal artery stenting. Registration URL: https://clinicaltrials.gov. Identifier: NCT02770066.