Prevalence of Atrial Fibrillation and Antithrombotic Therapy in Hemodialysis Patients: Cross-Sectional Results of the Vienna InVestigation of AtriaL Fibrillation and Thromboembolism in Patients on HemoDIalysis (VIVALDI).

BACKGROUND: Atrial fibrillation (AF) adds significant risk of stroke and thromboembolism in patients on hemodialysis (HD). The aim of this study was to investigate the prevalence of AF in a population-based cohort of HD patients and practice patterns of antithrombotic therapy for stroke prevention in AF. METHODS: The Vienna InVestigation of AtriaL fibrillation and thromboembolism in patients on hemodialysis (VIVALDI), an ongoing prospective observational cohort study, investigates the prevalence of AF and the risk of thromboembolic events in HD patients in Vienna, Austria. We analyzed cross-sectional data of 626 patients (63.4% men, median age 66 years, approx. 73% of HD patients in Vienna), who provided informed consent. A structured interview with each patient was performed, recent and archived ECGs were viewed and medical histories were verified with electronic records. RESULTS: The overall prevalence of AF was 26.5% (166 patients, 71.1% men, median age 72 years) of which 57.8% had paroxysmal AF, 3.0% persistent AF, 32.5% permanent AF, and 6.6% of patients had newly diagnosed AF. The median CHA2DS2-VASc Score was 4 [25th-75th percentile 3-5]. In multivariable analysis, AF was independently associated with age (odds ratio: 1.05 per year increase, 95% confidence interval: 1.03-1.07), male sex (1.7, 1.1-2.6), history of venous thromboembolism (2.0, 1.1-3.6), congestive heart failure (1.7, 1.1-2.5), history of or active cancer (1.5, 1.0-2.4) and time on HD (1.08 per year on HD, 1.03-1.13). Antithrombotic treatment was applied in 84.4% of AF patients (anticoagulant agents in 29.5%, antiplatelet agents in 33.7%, and both in 21.1%). In AF patients, vitamin-K-antagonists were used more often than low-molecular-weight heparins (30.1% and 19.9%). CONCLUSIONS: The prevalence of AF is high amongst HD patients and is associated with age, sex, and distinct comorbidities. Practice patterns of antithrombotic treatment indicate a lack of consensus for stroke prevention in HD patients with AF.

Recurrent posterior reversible encephalopathy syndrome in mitochondrial disorder.

OBJECTIVES: Recurrent posterior reversible encephalopathy syndrome (PRES) has not been reported in association with multi-system mitochondrial disorder (MID). CASE REPORT: In a 60-year-old HIV-negative, Caucasian female with short stature, double vision, struma, memory impairment, chronic renal failure requiring hemodialysis, seizures, intermittent atrial fibrillation, arterial hypertension, hyperlipidemia, anemia, hypacusis, tinnitus, and a daughter with multiple sclerosis, short stature and hypothyroidism; another daughter with schizophrenia, and a son who died from encephalopathy at age 3 months, an MID was suspected. At age 53 years, she experienced sudden, transient blindness for 2 days bilaterally during an episode of high blood pressure with complete recovery within 2 weeks. At age 60 years, a similar episode occurred. Four weeks later, she experienced a third PRES episode with high blood pressure, seizures, impaired consciousness and reversible blindness for 2 days. MRI at the second episode was indicative of a PRES, and MRI at the third episode additionally revealed occipital bleedings, acute embolic stroke and features indicating PRES. CONCLUSIONS: This case indicates that MID may be associated with recurrent PRES, triggered by recurrent episodes of high blood pressure. Whether high blood pressure was a manifestation of the MID or related to other causes remains speculative. PRES does not seem to be a primary but is rather a secondary manifestation of an MID.