Structural and functional characteristics of rat hearts with and without myocardial infarct. Initial experience with doppler echocardiography

Abstract

Objective -To assess by Doppler echocardiography the structural and functional alterations of rat heart with surgical induced extensive myocardial infarction. Methods -

Repercussões cardíacas após infarto do miocárdio em ratas submetidas previamente a exercício físico

“…Induction of MI followed a well-established protocol [20][21][22][23][24] . Briefly, after intraperitoneal anesthesia (ketamine 50 mg/kg and xylazine 20 mg/kg), intubation and mechanical ventilation (Harvard Rodent Ventilator, Model 863, Harvard Apparatus, Holliston, MA), thoracotomy was performed in the left hemithorax of each animal.…”

“…The procedures were performed by an observer blinded to the groups to which the animals had been assigned. A Sonos 5500 equipment (Philips Medical Systems, Andover, MA, USA) with a 12 -MHz transducer was used in a depth between 2 and 3 cm according to previously described methodology 20 . After having their thorax shaved, the animals were placed in the left lateral position.…”

Características fisiopatológicas do modelo de insuficiência cardíaca pós-infarto do miocárdio no rato

“…Although it identifies the presence of an MI-dependent electrically inactive area, the ECG is not a method that can quantify the infarction area 2 . The echocardiogram can determine the presence and the size of the MI with very good sensitivity [3][4][5][6][7][8][9][10][11][12][13][14][15] , even in periods as early as two days after necrosis, and it also provides information about deviant atrial and ventricular function. The best method for post-mortem diagnosis of MI depends on the stage in which the autopsy occurs.…”

“…The electrocardiogram 2 and the echocardiogram [3][4][5][6][7][8][9][10][11][12][13][14][15] are noninvasive methods capable of identifying the area of necrosis or scarring. Although it identifies the presence of an MI-dependent electrically inactive area, the ECG is not a method that can quantify the infarction area 2 .…”

Impacto da pesquisa básica nos avanços da cardiologia

“…This instrument has also been used consistently in the ABC for monitoring the process of cardiac remodeling secondary to various stimuli, particularly after experimental acute myocardial infarction 20,21 . Initially, the Doppler echocardiogram presented high sensitivity and specificity for the detection of large infarcts in the chronic phase and identified signs of increased ventricular cavity and pulmonary artery pressure 22 . Subsequently, it was shown that animals subjected to myocardial infarction presented two patterns of left ventricular geometry which were not factors predictive of ventricular dysfunction 23 .…”