title: Serial noninvasive assessment of progressive pulmonary hypertension in a rat model.
abstract: Current methods used to investigate pulmonary hypertension in rat models of the disease allow for only one to two measurements of pulmonary artery (PA) pressure in the life of a rat. We investigated whether transthoracic echocardiography can be used to assess the progression of pulmonary hypertension in rats at multiple time points. Serial echocardiographic measurements were performed over a 6-wk period on rats injected with monocrotaline (MCT) or placebo. Development of a midsystolic notch in the PA waveform, a decrease in the PA flow acceleration time (PAAT), an increase in right ventricular (RV) free-wall thickness, and the development of tricuspid regurgitation (TR) were observed as pulmonary hypertension developed. Changes in the PA waveform and PAAT began in week 3 of disease development as the PA systolic pressure (PASP) reached 25-30 mmHg according to right heart catheterization. The RV free-wall thickness increased significantly by week 5 (PASPs 40-50 mmHg). Development of quantifiable TR occurred in week 6 or at PASPs > 65 mmHg. A linear correlation was found between the PAAT and PASP in the range of 30-65 mmHg and between the RV-right atrial pressure gradient (derived from TR velocity) and PASP at pressures >65 mmHg, which enabled a noninvasive estimate of the PASP over a wide range of pressures based on these parameters. These data indicate that transthoracic echocardiography can be used for monitoring the progress of pulmonary hypertension in a rat model.
authors.affiliation: Department of Surgery, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
authors.forename: John E
authors.initials: JE
authors.lastname: Jones
authors.forename: Lisa
authors.initials: L
authors.lastname: Mendes
authors.forename: M Audrey
authors.initials: MA
authors.lastname: Rudd
authors.forename: Giulia
authors.initials: G
authors.lastname: Russo
authors.forename: Joseph
authors.initials: J
authors.lastname: Loscalzo
authors.forename: Ying-Yi
authors.initials: YY
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity; D001794:Blood Pressure; D006328:Cardiac Catheterization; D004195:Disease Models, Animal; D018450:Disease Progression; D004452:Echocardiography; D005240:Feasibility Studies; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006976:Hypertension, Pulmonary / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D017380:Hypertrophy, Right Ventricular / Q000000981:diagnostic imaging / Q000209:etiology; D008297:Male; D011651:Pulmonary Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology; D051381:Rats; D015203:Reproducibility of Results; D014262:Tricuspid Valve Insufficiency / Q000000981:diagnostic imaging / Q000209:etiology