Echocardiographic assessment of left ventricular midwall mechanics in spontaneously hypertensive rats

Aims. The present study was attempted to determine whether LV midwall mechanics yielded different conclusions about LV systolic function than the assessment of endocardial LV mechanics by echocardiography in spontaneously hypertensive rats (SHR). Methods and results. Thirty-six (18 Wistar normotensi...

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Detalles Bibliográficos
Autores: Escudero, Eduardo Manuel, Camilión de Hurtado, María Cristina, Pérez, Néstor Gustavo, Tufare, Ana Laura
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2004
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/84464
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/84464
Access Level:acceso abierto
Palabra clave:Ciencias Médicas
Echocardiography
Left ventricular function
Left ventricular hypertrophy
Midventricular mechanics
Descripción
Sumario:Aims. The present study was attempted to determine whether LV midwall mechanics yielded different conclusions about LV systolic function than the assessment of endocardial LV mechanics by echocardiography in spontaneously hypertensive rats (SHR). Methods and results. Thirty-six (18 Wistar normotensive (W), 18 [SHR]) anesthetized rats were studied with two-dimensional directed M-mode echocardiogram to analyze LV structure (LV diameter, left ventricular wall thickness and LV mass [LVM]) and LV function (endocardial shortening [ES] and midwall shortening [MS]). Measurements were made from three consecutive cardiac cycles on the M-mode tracings. There was no significant difference in LV dimension. LVM was higher in SHR (SHR: 595 ± 111 mg, W: 413 ± 83 mg - p < 0.01). ES was higher in SHR (SHR: 64.1 ± 6%, w: 58.2 ± 4% - p < 0.01), whereas no significant difference was found in MS (SHR: 27 ± 4%, W: 27.6 ± 4% - ns). Twelve of 18 (66%) SHR showed endocardial shortening higher than normally predicted, compared with 3/18 (16%) with observed enhanced MS (p < 0.01). Conclusion. These results suggest that the analysis of midwall mechanics by echo allows us to better understand the LV performance in SHR and that the exaggerated endocardial motion could not represent a really <i>supernormal</i> systolic performance.