title: Rats with high left ventricular end-diastolic pressure can be identified by Doppler echocardiography one week after myocardial infarction.
abstract: The severity of left ventricular (LV) dysfunction in rats with myocardial infarction (MI) varies widely. Because homogeneity in baseline parameters is essential for experimental investigations, a study was conducted to establish whether Doppler echocardiography (DE) could accurately identify animals with high LV end-diastolic pressure as a marker of LV dysfunction soon after MI. Direct measurements of LV end-diastolic pressure were made and DE was performed simultaneously 1 week after surgically induced MI (N = 16) or sham-operation (N = 17) in female Wistar rats (200 to 250 g). The ratio of peak early (E) to late (A) diastolic LV filling velocities and the ratio of E velocity to peak early (Em) diastolic myocardial velocity were the best predictors of high LV end-diastolic pressure (>12 mmHg) soon after MI. Cut-off values of 1.77 for the E/A ratio (P = 0.001) identified rats with elevated LV end-diastolic pressure with 90% sensitivity and 80% specificity. Cut-off values of 20.4 for the E/Em ratio (P = 0.0001) identified rats with elevated LV end-diastolic pressure with 81.8% sensitivity and 80% specificity. Moreover, E/A and E/Em ratios were the only echocardiographic parameters independently associated with LV end-diastolic pressure in multiple linear regression analysis. Therefore, DE identifies rats with high LV end-diastolic pressure soon after MI. These findings have implications for using serial DE in animal selection and in the assessment of their response to experimental therapies.
authors.affiliation: Disciplina de Cardiologia, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São PauloSão Paulo, SP, Brasil.
authors.forename: R M
authors.initials: RM
authors.lastname: Saraiva
authors.forename: R M
authors.initials: RM
authors.lastname: Kanashiro-Takeuchi
authors.forename: E L
authors.initials: EL
authors.lastname: Antonio
authors.forename: O
authors.initials: O
authors.lastname: Campos
authors.forename: Tucci
authors.initials: T
authors.lastname: P J F
authors.forename: V A
authors.initials: VA
authors.lastname: Moisés
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D015150:Echocardiography, Doppler; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D009203:Myocardial Infarction / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology