Vivid 7 dimension

We assess left ventricle diameters, volumes, systolic and diastolic function according to American Society of Echocardiography guidelines for chamber quantification.^{[25 (link)]} We use Vivid 7 Dimension echocardiographic machine with integrated software (GE, Horten, Norway) for measurements.

It was performed on an expert class apparatus ‘Vivid-7 Dimension’ (General Electric, USA) by two-dimensional echocardiography, Doppler echocardiography in pulsed and continuous wave mode, color Doppler scanning (CDS) in accordance with the current [9 (link)]. Diameter and thickness of the LV walls were measured in the two-dimensional M-mode. Left heart analysis included assessment of the size and volumetric parameters of the left ventricle, left ventricular mass, the maximum transverse diameter of the left atrium in the diastole (LA). Ejection fraction of the left ventricle (LVEF) was calculated according to the Simpson method.
Left ventricular diastolic parameters were studied using pulsed-wave Doppler imaging, including peak velocity of early (E) and late (A) transmitral filling of the left ventricle and their ratio (E/A) and the isovolumetric relaxation time of the left ventricle. The study was carried out within the first two days from the moment the patient was admitted to the hospital.

Cardiac morphology and function were assessed by transthoracic echocardiography at week −1, 4, and 8 (Fig. 1). Rats were anesthetized with 2% isoflurane (Forane, AESICA, Queenborough Limited Kent, UK). Then, the chest was shaved, and the rat was placed in a supine position onto a heating pad. Two-dimensional, M-mode, Doppler, and tissue Doppler echocardiographic examinations were performed by the criteria of the American Society of Echocardiography with a Vivid 7 Dimension ultrasound system (General Electric Medical Systems) using a phased array 5.5–12 MHz transducer (10S probe) as described previously^{63 (link)–65 (link)}. Data of three consecutive heart cycles were analysed (EchoPac Dimension software; General Electric Medical Systems) by an experienced investigator in a blinded manner. The mean values of three measurements were calculated and used for statistical evaluation.

The ABI of each foot was calculated by dividing the higher pressure in the posterior tibial or dorsalis pedis arteries by the higher systolic blood pressure in the right or left arm. To record blood pressure, a Doppler probe was placed over the pulsing artery at a 45° to 60° angle to the surface of the skin [20 (link)].
The level and severity of arterial stenosis were assessed by the duplex ultrasound scanning of the lower limb arteries using the Philips Affinity 50 (Philips Ultrasound, Tampa, Florida, USA) and the Vivid 7 Dimension (GE Healthcare, Chicago, Illinois, USA). The ultrasound protocol involved assessing the presence of hemodynamically significant stenoses (at least 50% of the diameter reduction) in 6 main arteries of each lower limb (common femoral artery, deep femoral artery, superficial femoral artery, popliteal artery, anterior tibial artery, posterior tibial artery).

Conventional echocardiography was performed on forty-eight New Zealand white rabbits using the GE Vivid7 Dimension ultrasound machine. Preoperative and postoperative LV end-systolic volume (LVESV), end-diastolic volume (LVEDV), stroke volume (SV) and LV ejection fraction (LVEF) were recorded in the rabbits, and standard high frame rate apical four, three and two-chamber views of three consecutive cardiac cycles were stored for off-line analysis.

Open chest, epicardial echocardiography was performed according to the American Society of Echocardiography Guidelines for Comprehensive Epicardial Echocardiography Examination using GE Vivid 7 Dimension ultrasound system equipped with a 10 MHz phased‐array transducer (GE Vingmed, Horton, Norway). A bovine liver tissue offset was used to enhance image quality; all images were optimized for speckle tracking analysis by manually adjusting sector widths to optimize speckle quality and maintaining frame rates 55–90 frames/sec. Echocardiographic and hemodynamic data were acquired simultaneously at baseline and 1, 5, and 15 minutes after induction of ischemia. Measurements were repeated 1, 15, and 30 minutes after reperfusion. All images were obtained by the same echocardiographer (EM).

To monitor cardiac function, transthoracic echocardiography was performed using a Vivid 7 Dimension imaging system (GE Medical Systems, Munich, Germany) equipped with a 14 MHz scanning head (i13L Probe). During the procedure, mice were anesthetized with 2% (vol) isoflurane in oxygen (0.5 l/min) via a respiratory mask and placed in dorsal position on a 37°C heating plate. Left ventricular wall and chamber dimensions as well as heart rate were measured in the M-Mode. Ejection fraction (EF) was calculated as described previously [18 (link)]. In TAC and sham mice, the aortic diameter was assessed before and 2 or 4 weeks after surgery.