Anne-Marie Koop

5 205 3. Echocardiography 3.1. Preparation 3.1.1. Perform PAB gradient analysis by means of echocardiography 14 days after PAB surgery. 3.1.2. Start the echocardiography device. Choose the cardiac package and a 14.0 MHz transducer. 3.2. Anesthesia 3.2.1. Place the mouse in the induction chamber filled with a mixture of 5% isoflurane and 100% oxygen. 3.2.2. Shave the thorax of the mouse. 3.2.3. Place the mouse on its back on the heat mat (temperature 37 °C) and place the snout in the ventilation mask. 3.2.4. Ventilate with a mixture of 1.5%–2.5% isoflurane and 100% oxygen (0.15 L/min) and room air (0.3 L/min). 3.2.5. Check the depth of the anesthesia by performing a toe pinch and adjust the anesthesia accordingly. 3.2.6. Prevent dehydration of the eye by using eye ointment. 3.3. Determination of PAB gradient by echocardiography 3.3.1. Place pediatric electrocardiogram-stickers on each foreleg and one on both hind legs. Use the stickers to hold the animal. 3.3.2. Apply ultrasound gel to the shaved part of the mouse’s thorax. 3.3.3. To obtain the images of the pulmonary artery, two views can be used: the parasternal long axis (PLAX) or the parasternal short axis (PSAX) view. Obtain both and use the view that gives the best quality measurements and highest velocities for analysis. 3.3.4. Obtain PLAX and PSAX views. 3.3.5. Press the color-Doppler button to visualize blood flow. 3.3.6. Place the ultrasound probe at a 30° angle to the parasternal line to obtain PLAX (for detailed description see Cheng, et al. 48 the RV is significantly affected in pulmonary diseases such as pulmonary artery hypertension (PAH), visualizing the ascending aorta.