title: Preload reduction to unmask the characteristic Doppler features of constrictive pericarditis. A new observation.
abstract: BACKGROUND
  Respiratory variation of > or = 25% in mitral E velocity is a characteristic Doppler echocardiographic feature in constrictive pericarditis. However, a subset of patients with constriction do not exhibit the typical respiratory change, most likely because of marked increase in the left atrial pressure, and preload reduction may unmask the respiratory variation.
  
  
  RESULTS
  In 12 patients with surgically confirmed constrictive pericarditis who had < 25% respiratory variation in mitral E velocity during an initial preoperative examination, the Doppler study was repeated after an attempt to decrease left ventricular filling pressure. At baseline, mean mitral E velocity was similar after inspiration and expiration (0.81 +/- 0.24 and 0.84 +/- 0.21 m/s, respectively). On repeat Doppler examination, with the patient in a head-up tilt or sitting position the decrease in mitral E velocity with inspiration (0.61 +/- 0.13 m/s) was significant (P < .004), whereas it did not change significantly with expiration. The mean percent respiratory change in E velocity was 5 +/- 7% at baseline and 32 +/- 28% with preload reduction. Eight (75%) of the 12 patients developed respiratory variation of > or = 25%.
  
  
  CONCLUSIONS
  When the respiratory variation in Doppler mitral E velocity is blunted or absent during the evaluation of suspected constrictive pericarditis, repeat Doppler recording of mitral flow velocities after maneuvers to decrease preload is recommended to unmask the characteristic respiratory variation in mitral E velocity.
authors.affiliation: Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, Rochester, Minn 55905, USA.
authors.forename: J K
authors.initials: JK
authors.lastname: Oh
authors.forename: A J
authors.initials: AJ
authors.lastname: Tajik
authors.forename: C P
authors.initials: CP
authors.lastname: Appleton
authors.forename: L K
authors.initials: LK
authors.lastname: Hatle
authors.forename: R A
authors.initials: RA
authors.lastname: Nishimura
authors.forename: J B
authors.initials: JB
authors.lastname: Seward
mesh_terms: D004452:Echocardiography; D015150:Echocardiography, Doppler; D006801:Humans; D008943:Mitral Valve / Q000000981:diagnostic imaging* / Q000503:physiopathology; D010492:Pericardiectomy; D010494:Pericarditis, Constrictive / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D010496:Pericardium / Q000000981:diagnostic imaging / Q000503:physiopathology; D013599:Systole; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right