title: Oliguric acute kidney injury as a main symptom of bradycardia and arteriosclerosis resolved by pacemaker implantation: a case report.
abstract: BACKGROUND
  Cardiovascular comorbidities regularly determine renal function. We report a case of acute kidney injury (Acute Kidney Injury Network stage 3) due to an intermittent third-degree atrioventricular block, which had not been diagnosed before.
  
  
  METHODS
  A 76-year-old Caucasian man with liver cirrhosis due to non-alcoholic fatty liver disease, and type-2 diabetes was cognitively impaired and had reduced vigilance presumably caused by hepatic encephalopathy and/or Alzheimer dementia. Within 2 years, two hospitalizations occurred for syncope attributed to orthostatic failure and hypovolemia. During the last hospitalization, oliguric acute kidney injury occurred. Sonography ruled out a post-renal cause. His renal resistive index was 1.0; his heart rate was below 50 beats per minute. After cessation of beta-blocker therapy, Holter electrocardiogram showed a new intermittent third-degree atrioventricular block with pauses for less than 3 seconds. Pacemaker insertion resolved his acute kidney injury, despite resumption of beta-blocker therapy. During four months of follow-up, syncope has not occurred, and vigilance was stable. However, his renal resistive index of 1.0 remained.
  
  
  CONCLUSIONS
  Here, typical neurologic symptoms of bradycardia were misclassified. Diagnostic work-up of oliguric acute kidney injury revealed intermittent third-degree heart block. The pathomechanism of acute kidney injury relates to relevant bradycardia and increased vascular stiffness attenuating arterial diastolic renal blood flow.
authors.affiliation: Department of Internal Medicine II, University Hospital Halle, Martin Luther University of Halle-Wittenberg, Halle, Saale, Germany. rainer.pliquett@medizin.uni-halle.de.
authors.forename: Rainer U
authors.initials: RU
authors.lastname: Pliquett
authors.forename: Daniel
authors.initials: D
authors.lastname: Radler
authors.forename: Alexander
authors.initials: A
authors.lastname: Tamm
authors.forename: Daniel
authors.initials: D
authors.lastname: Greinert
authors.forename: Robin
authors.initials: R
authors.lastname: Greinert
authors.forename: Matthias
authors.initials: M
authors.lastname: Girndt
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology*; D000368:Aged; D001161:Arteriosclerosis / Q000150:complications / Q000175:diagnosis*; D054537:Atrioventricular Block / Q000150:complications / Q000175:diagnosis* / Q000628:therapy; D001919:Bradycardia / Q000150:complications / Q000175:diagnosis* / Q000628:therapy; D059347:Cardio-Renal Syndrome / Q000175:diagnosis* / Q000628:therapy; D006801:Humans; D008297:Male; D009846:Oliguria / Q000209:etiology*; D010138:Pacemaker, Artificial