Efeitos da inibição prolongada da enzima de conversão da angiotensina sobre as características morfológicas e funcionais da hipertrofia ventricular esquerda em ratos com sobrecarga pressórica persistente Effects of the prolonged inhibition of the angiotensin-converting enzyme on the morphological and functional characteristics of left ventricular hypertrophy in rats with persistent pressure overload

Abstract

OBJETIVO: Avaliar os efeitos do lisinopril (L) sobre as taxas de mortes (M), insuficiência cardíaca (ICC), características da remodelação miocárdica, geométrica e funcional do ventrículo esquerdo (VE), em ratos com estenose aórtica supravalvar (EAS). MÉTODOS: Ratos foram submetidos a EAS ou cirurgia simulada (GC:n=10). Randomizados após 6 semanas para receber L (GL:n=30) ou nenhum tratamento (GE:n=73) sendo avaliados 6s e 21s por estudos ecocardiográfico, hemodinâmico e morfológico concomitantes. RESULTADOS: As taxas de M (GE: 53,9% vs GL: 16,7% e ICC GE: 44,8% vs GL: 20% p0,05) sendo ambos maiores que os verificados no grupo GE. Comportamento semelhante foram obtidos com os valores da primeira derivada positiva e negativa da pressão do VE. CONCLUSÃO: Em ratos com EAS o L reduziu as taxas de M e ICC e exerceu efeitos benéficos sobre a remodelação e a função do VE.OBJECTIVE: To assess the effects of lisinopril (L) on mortality (M) rate and congestive heart failure (CHF), and the characteristics of geometrical myocardial remodeling and left ventricular function in rats with supravalvular aortic stenosis (SAS). METHODS: Some Wistar rats underwent SAS or the simulated surgery (CG, n=10). After 6 weeks, the animals were randomized to receive lisinopril (LG, n=30) or no treatment (SG, n=73) for 15 weeks. Cardiac remodeling was assessed in the sixth and 21st weeks after the surgical procedures through concomitant echocardiographic, hemodynamic, and morphological studies. RESULTS: The M were 53.9% and 16.7% in SG and LG, respectively; the incidence of CHF was 44.8% and 20%, in SG and LG, respectively, (P0.05), and both were greater than those in SG;(P<0.05). Similar results were obtained with the values of the positive and negative first derivate of LV pressure. CONCLUSION: In rats with SAS, the treatment with L reduced M rate and ICC and had beneficial effects on geometrical myocardial remodeling and left ventricular function.

Keywords

• hipertrofia cardíaca
• hipertensão arterial
• inibidores da enzima conversora de angiotensina
• lisinopril
• função ventricular
• cardiac hypertrophy
• arterial hypertension
• angiotensin-converting enzyme inhibitors
• lisinopril
• ventricular function