Improved systolic ventricular function with normal myocardial mechanics in compensated cardiac hypertrophy
Restricciones de acceso
MetadatosMostrar el registro completo del ítem
There still controversy about the relation between changes in myocardial contractile function and global left ventricular (LV) performance during stable concentric hypertrophy. To clarify this, we analyzed LV function in vivo and myocardial mechanics in vitro in rats with pressure overload-induced cardiac hypertrophy. Male Wistar rats (70 g) underwent ascending aorta stenosis for 8 weeks (group AAS, n=9). LV performance was assessed by transthoracic echocardiography under light anesthesia. Myocardial function was studied in isolated papillary muscle preparation during isometric contraction. The data were compared with age- and sex-matched sham-operated rats (group C, n=9). LV weight-to-body weight ratio (C: 2.0 ± 0.5 mg/g; AAS: 3.3 ± 0.7 mg/g), LV relative wall thickness (C: 0.19 ± 0.02; AAS; 0.34 ± 0.10), and LV fractional shortening (C: 54 ± 5%; AAS: 70 ± 8%) were increased in the group AAS (p<0.05). Echocardiographic analysis also indicated a significant association (r=0.74; p<0.001) between percent fractional shortening and LV relative wall thickness. The performance of AAS isolated muscle revealed that active tension (C: 6.6 ± 1.7 g/mm 2; AAS: 6.5 ± 1.5 g/mm 2) and maximum rate of tension development (C: 69 ± 21 g/mm 2/s; AAS: 69 ± 18 g/mm 2) were not significantly different from group C (p>0.05). In conclusion: 1) Compensated pressure-overload myocardial hypertrophy is associated with preserved myocardial function and increased ventricular performance; 2) The improved LV function might be due to the ventricular remodeling characterized by an increased relative wall thickness. Copyright © 2002 By PJD Publications Limited.
Cómo citar este documento
Mostrando ítems relacionados por Título, autor o materia.
Soriano, Eline A. ; Gaiolla, Paula Schmidt Azevedo ; Miot, Hélio Amante ; Minicucci, Marcos Ferreira ; Pansani, Mariele C. ; Matsubara, Luiz Shiguero ; Okoshi, Katashi ; Zornoff, Leonardo Antonio Mamede ; Matsubara, Beatriz Bojikian ; Paiva, Sergio A.R. (International Journal of Cardiology, 2013) [Artigo]Background: Currently, 13-cis-retinoic acid (13-cis-RA) is the most effective therapy for acne. Isotretinoin, a first-generation synthetic 13-cis-RA compound, is associated with numerous adverse effects. To investigate the ...
Damatto, R. L. ; Martinez, P. F. ; Lima, A. R R ; Cezar, M. D M ; Campos, D. H S ; Oliveira Junior, S. A. ; Guizoni, D. M. ; Bonomo, C. ; Nakatani, B. T. ; Dal Pai Silva, M. et al. (International Journal of Cardiology, 2013) [Artigo]Background: Although skeletal muscle atrophy and changes in myosin heavy chain (MyHC) isoforms have often been observed during heart failure, their pathophysiological mechanisms are not completely defined. In this study ...
Waist circumference, but not body mass index, is a predictor of ventricular remodeling after anterior myocardial infarction Cogni, Ana Lucia ; Farah, Elaine ; Minicucci, Marcos Ferreira ; Gaiolla, Paula Schmidt Azevedo ; Okoshi, Katashi ; Matsubara, Beatriz Bojikian ; Zanati, Silméia G. ; Paiva, Sergio A.R. ; Zornoff, Leonardo Antonio Mamede (Nutrition, 2013) [Artigo]Objective: The impact of obesity on ventricular remodeling after myocardial infarction (MI) is still poorly understood. Therefore, the aim of this study was to evaluate the role of waist circumference (WC) and body mass ...