title: Myocardial fluid balance in dogs with naturally acquired heartworm infection.
abstract: OBJECTIVE
  To determine the effect of naturally acquired heartworm (Dirofilaria immitis) infection on myocardial fluid balance as indicated by myocardial water content and the dynamics of transepicardial fluid flow.
  
  
  METHODS
  7 dogs infected with adult heartworms and 8 dogs free of heartworm infection.
  
  
  METHODS
  Infected dogs had heartworms in the right ventricle, pulmonary artery, or both but no evidence of cardiovascular disease on physical examination. A hemispheric capsule was attached to the epicardial surface of all dogs for determination of transepicardial fluid dynamics and permeability of the epicardium to water and protein. Myocardial water content and hydroxyproline content were assessed at necropsy.
  
  
  RESULTS
  Myocardial water content was significantly lower in heartworm-infected dogs. No differences in myocardial hydroxyproline content, transepicardial fluid flow, or epicardial water or protein permeability were detected.
  
  
  CONCLUSIONS
  Heartworm infection significantly altered myocardial fluid balance in dogs, possibly because of a change in the myocardial interstitial pressure-volume relationship. These changes may be associated with increased vulnerability to cardiovascular stressors in heartworm-infected dogs.
authors.affiliation: Michael E. DeBakey Institute, Texas A&M University, College Station, TX 77843, USA.
authors.forename: Randolph H
authors.initials: RH
authors.lastname: Stewart
authors.forename: Karen
authors.initials: K
authors.lastname: Uray
authors.forename: Charles S
authors.initials: CS
authors.lastname: Cox
authors.forename: Glen A
authors.initials: GA
authors.lastname: Laine
mesh_terms: D000818:Animals; D009202:Cardiomyopathies / Q000378:metabolism / Q000469:parasitology*; D004182:Dirofilaria / Q000254:growth & development*; D004184:Dirofilariasis / Q000378:metabolism* / Q000469:parasitology*; D004283:Dog Diseases / Q000378:metabolism* / Q000469:parasitology*; D004285:Dogs; D005260:Female; D006909:Hydroxyproline / Q000378:metabolism; D008297:Male; D009997:Osmotic Pressure; D014882:Water-Electrolyte Balance / Q000502:physiology*
chemical_list: D006909:Hydroxyproline