Author(s): Ribeiro Henrique Barbosa | Okoshi Katashi | Cicogna Antonio Carlos | Bregagnollo Edson Antonio | Rodrigues Maria Aparecida Marchesan | Padovani Carlos Roberto | Aragon Flávio Ferrari | Jamas Elenize | Okoshi Marina Politi
Journal: Arquivos Brasileiros de Cardiologia
ISSN 0066-782X
Volume: 81;
Issue: 6;
Start page: 569;
Date: 2003;
Original page
Keywords: myocardial hypertrophy | echocardiogram | ventricular function | aortic stenosis and rats
ABSTRACT
OBJECTIVE: To characterize the follow-up of an experimental model of left ventricular hypertrophy (LVH) induced by supravalvular ascending aortic stenosis in young rats. METHODS: Wistar rats were submitted to thoracotomy and aortic stenosis was created by placing a clip on the ascending aorta (AoS group, n=12). Age-matched control animals underwent a sham operation (C group, n=12). Cardiac function was analysed by echocardiograms performed 6, 12, and 21 weeks after aortic banding. Myocardial morphological features and myocardial hydroxyproline concentration (HOP) were evaluated 2, 6, 12, and 21 weeks after surgery in additional animals. RESULTS: Aortic banding promoted early concentric LVH and a progressive increase in HOP. Under light microscopy, we observed myocyte hypertrophy and wall thickening of the intramural branches of the coronary arteries due to medial hypertrophy. Cardiac function was supranormal after 6 weeks (percentage of fractional shortening - EAo6: 70.3±10.8; C6: 61.3±5.4; p
Journal: Arquivos Brasileiros de Cardiologia
ISSN 0066-782X
Volume: 81;
Issue: 6;
Start page: 569;
Date: 2003;
Original page
Keywords: myocardial hypertrophy | echocardiogram | ventricular function | aortic stenosis and rats
ABSTRACT
OBJECTIVE: To characterize the follow-up of an experimental model of left ventricular hypertrophy (LVH) induced by supravalvular ascending aortic stenosis in young rats. METHODS: Wistar rats were submitted to thoracotomy and aortic stenosis was created by placing a clip on the ascending aorta (AoS group, n=12). Age-matched control animals underwent a sham operation (C group, n=12). Cardiac function was analysed by echocardiograms performed 6, 12, and 21 weeks after aortic banding. Myocardial morphological features and myocardial hydroxyproline concentration (HOP) were evaluated 2, 6, 12, and 21 weeks after surgery in additional animals. RESULTS: Aortic banding promoted early concentric LVH and a progressive increase in HOP. Under light microscopy, we observed myocyte hypertrophy and wall thickening of the intramural branches of the coronary arteries due to medial hypertrophy. Cardiac function was supranormal after 6 weeks (percentage of fractional shortening - EAo6: 70.3±10.8; C6: 61.3±5.4; p