title: Influence of cardiac resynchronization therapy on oxidative stress markers in patients with chronic heart failure.
abstract: BACKGROUND
  The aim of the study was to assess changes of substances of oxidative stress in patients treated with cardiac resynchronization therapy (CRT).
  
  
  METHODS
  The study comprised 51 patients with median age of 66 years. The presence, severity, and changes of oxidative stress during CRT were assessed and expressed as malondialdehyde (MDA) concentration in plasma or in red blood cells. Antioxidant activity was assessed by the activity of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) in red blood cells. The concentration and activities were analyzed directly prior to implantation, 2-5 days after the procedure and after 6 months. Follow-up (6 months) included clinical, echocardiographic and implanted device assessments.
  
  
  RESULTS
  During the follow-up, 14% patients died. The median percentage of biventricular pacing was 99.29%. After 6 months 88% of patients improved NYHA, 12% remained as non-responders. Left ventricular ejection fraction increased from median 21.5% to 29% (p < 0.05). Left ventricular end-diastolic diameter decreased significantly from a median of 69.5 mm to 63 mm (p < 0.05). After a 6-month study, MDA plasma concentration and the activity levels of each antioxidant enzymes (CAT, SOD, GPx) showed a statistically significant reduction (p < 0.05). Changes concerning MDA concentrations in red blood cells remained statistically insignificant.
  
  
  CONCLUSIONS
  Resynchronization effect oxidative stress by reducing plasma concentration of MDA, CAT, SOD and GPX.
authors.affiliation: Department of Cardiology and Inter nal Medicine, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland. wkrupa@cm.umk.pl.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Krupa
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Rozwodowska
authors.forename: Sławomir
authors.initials: S
authors.lastname: Sielski
authors.forename: Ewa
authors.initials: E
authors.lastname: Czarnecka-Żaba
authors.forename: Tomasz
authors.initials: T
authors.lastname: Fabiszak
authors.forename: Gerard
authors.initials: G
authors.lastname: Drewa
authors.forename: Michał
authors.initials: M
authors.lastname: Kasprzak
authors.forename: Jacek
authors.initials: J
authors.lastname: Kubica
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood*; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis / Q000378:metabolism* / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D015415:Biomarkers