Critérios ecocardiográficos para definição de graus de disfunção ventricular em ratos portadores de estenose aórtica

Abstract

M a i l i n d A d d r e s s : K a t a s h i O k o s h i• T r a v e s s a C y r o T a r g a , 1 1 5 -1 8 6 1 0 -2 5 0 -B o t u c a t u , S P -B r a z i l E-mail: okoshi@cardiol. OBJECTIVEThe purpose of this study was to identify echocardiographic parameters that allow distinguishing different levels of cardiac dysfunction in aortic banded rats. METHODSWistar male rats (90-100 g) were subjected to aortic banding (n=23) or a sham operation (n=12). The following echocardiographic parameters were evaluated and used to group rats into groups with similar characteristics using cluster analysis: absolute values and after normalization to body weight of left ventricular enddiastolic diameter (LVDD) and left atrial systolic diameter; left ventricular end-systolic diameter (LVSD); LV weight to body weight ratio (LVW/BW); three indexes of left ventricular shortening (endocardial fractional shortening, EFS; midwall FS, MFS; and posterior wall shortening velocity, (PWSV). RESULTSThe cluster analysis could group aortic banded rats into two groups: mild (n=13) and severe (n=9) stage of heart failure. There was no overlapping among the values of the 95% confi dence interval of the following parameters between the two groups: LVDD, LVSD, EFS, MFS, LVW/BW, and PWSV. CONCLUSIONIt is feasible to distinguish two groups of aortic banded rats according to the level of cardiac dysfunction using those echocardiographic parameters. This allows to perform longitudinal studies in homogeneous groups of rats with aortic banding and cardiac dysfunction.

Diabetes mellitus activates fetal gene program and intensifies cardiac remodeling and oxidative stress in aged spontaneously hypertensive rats

“…When normalized to body weight, LV diastolic diameter and left atrium diameter were higher in SHR-DM than SHR. Normalization of cardiac structural parameters to body weight can lead to misinterpretation of results as cardiac chambers diameters are not exactly proportional to body weight [41]. Therefore, our data suggest that DM increases LV systolic diameter without dilating LV or left atrium in spontaneously hypertensive rats.…”

Digoxin Induces Cardiac Hypertrophy Without Negative Effects on Cardiac Function and Physical Performance in Trained Normotensive Rats

“…Meanwhile, Sullivan et al [31] observed significant improvement in physical performance in patients aged 40-75 years who had CHF treated with a digoxin dose of 0.25 mg/day. Morisco et al [23] evaluated 10 patients with CHF treated for 3 weeks with digoxin at a dosage of 0.25 mg/kg and found some improvements in the exercise capacity of the patients studied. This difference in the results may be related to the drug dosage, type of stress, and clinical conditions of the individuals tested, because digoxin may be more sensitive to heart failure conditions.…”

Remodelamento cardíaco: análise seriada e índices de detecção precoce de disfunção ventricular

“…These periods are suitable to observing morphological and functional alterations in rats with SVA and precede appearance of HF, which takes place around the 20 th week 9,10,13 .…”

“…Heart's function and structure were analyzed by means of ECHO according to methodology used in our lab 4,9,10,14 . Animals were anesthetized with ketamine chloride (50 mg/kg) and xylazine chloride (1 mg/kg), intraperitoneal.…”

“…SVAS advantages are: gradual development of CR, associated in short term to the improvement of systolic function; absence of severe lesions in myocardial anatomy; and low maintenance cost 9 . Around the 20 th week of SVAS, deterioration of systolic performance and HF [10][11][12][13] begin. This model is partially similar to SVAS in men 11 .…”