title: Citric acid as a decalcifying agent for the excised calcified human heart valves.
abstract: OBJECTIVE
  Cardiac valvular pathologies are frequently encountered as mechanical and functional disorders due to the calcification of the valves whatever the etiologies are. This pathophysiologic table usually ends up with valvular replacement. In this study, we aimed to decrease/eliminate the calcium in the excised calcified human heart valves by using citric acid in vitro hence bringing about the question for possible oral treatment of calcification of the valves by citric acid ingestion.
  
  
  METHODS
  Fourteen pieces of mitral and/or aortic valves excised from 12 patients undergoing valve replacement were placed in a freshly prepared phosphate buffered saline solution containing 0.625% glutaraldehyde at +4 0C for 48 h. They were rinsed with 0.9% NaCl and divided into two groups; study and control. Control tissues were further treated in a freshly prepared solution with identical properties for another 5 days. Study tissues were placed into a solution containing 3.8% citric acid (pH 7.4) and kept for 48 h at +37 degrees C, then rinsed with 0.9% NaCl and transferred into a fresh solution containing 0.625% glutaraldehyde with phosphate buffer at 37 0C for 3 more days. Specimens were biochemically and histopathologically evaluated and compared using Mann Whitney U test.
  
  
  RESULTS
  Calcium and phosphate levels in the study group were lower than in the control group (852.5+/-913.41 microg g-1 vs 413.05+/-519.53 microg g-1, p=0.001 and 207.6+/-321.86 microg g-1 vs 124.4+/-289.48 microg g-1, p=0.035, respectively). Malondialdehyde and protein level values were changed insignificantly in the control and study groups. Histopathologic evaluation showed that collagen and elastin fibers were similar in both groups. In the study group, irregular and fusiform calcific formations around the collagen fibers were significantly decreased.
  
  
  CONCLUSIONS
  Decalcifying human heart valves in vitro conditions with citric acid without an adverse change to the morphology of the valvular tissue specimens is meaningful. We believe that forwarding and looking for the answer to the question "whether systemic application of citric acid could lead to the decalcification and/or reduction of calcification in the native human heart valves" would be expressive.
authors.affiliation: From Department of Cardiovascular Surgery, Faculty of Medicine, Mersin University, Mersin, Turkey.
authors.forename: Necmi
authors.initials: N
authors.lastname: Köse
authors.forename: Barlas Naim
authors.initials: BN
authors.lastname: Aytaçoğlu
authors.forename: Necat
authors.initials: N
authors.lastname: Yilmaz
authors.forename: H Ali
authors.initials: HA
authors.lastname: Döndaş
authors.forename: Lülüfer
authors.initials: L
authors.lastname: Tamer
authors.forename: Banu
authors.initials: B
authors.lastname: Coşkun
authors.forename: Ozden
authors.initials: O
authors.lastname: Vezir
authors.forename: Nehir
authors.initials: N
authors.lastname: Sucu
authors.forename: Murat
authors.initials: M
authors.lastname: Dikmengil
mesh_terms: D000328:Adult; D001024:Aortic Valve Stenosis / Q000188:drug therapy / Q000473:pathology; D002114:Calcinosis / Q000188:drug therapy / Q000473:pathology; D016022:Case-Control Studies; D002614:Chelating Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D019343:Citric Acid / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D005260:Female; D006349:Heart Valve Diseases / Q000188:drug therapy / Q000473:pathology; D006351:Heart Valves / Q000187:drug effects* / Q000473:pathology / Q000648:ultrastructure; D006801:Humans; D008297:Male; D008946:Mitral Valve Stenosis / Q000188:drug therapy / Q000473:pathology
chemical_list: D002614:Chelating Agents; D019343:Citric Acid