Fall, 2017

Risk factors for dilation of the thoracic ascending aorta are age greater than 65, high blood pressure, family history, tobacco use, Marfan Syndrome and related disorders, or atherosclerosis.

Measuring the ascending aorta as far up as you are able in the parasternal view should already be a standard part of your echo protocol, with several measurements preferred and displayed. The IAC is not specific with regard to exact locations to measure, as this will vary according to patient anatomy.

Even if these measurements are within normal limits for the ascending aorta diameter (
The right parasternal window images are not difficult to obtain, even with obese patients, and most of the time, I have been able to obtain, and measure, a useful image. Once the patient has rolled up on his or her right side, ask him or her to place the right arm on the pillow up behind the head, or extended straight back on the pillow. The left arm may remain down by the patient’s side. If a female patient’s gown is open to the back, ask her to slip her left arm out of her gown and place it by her side. This will allow the sonographer unhindered access to the thoracic ascending aorta. The sonographer orients the transducer with the notch in the same direction as when obtaining standard parasternal images and, starting fairly high on the patient’s chest, look for the aorta. It will appear as a “tube” displayed transversely. Measurements should be obtained in as many locations as can be imaged. Some patients will have several centimeters of the aorta visible, and measurements should be obtained from as much of the vessel as the sonographer is able to display.

In many situations, I have found measurements of the thoracic ascending aorta to be normal in the parasternal view, but will find a dilated aorta (>3.8 cm) in the right parasternal view. Measurements over 4 cm should be routinely evaluated and, by current thinking, a thoracic ascending aorta should be repaired if it reaches 5 centimeters. Repair of the aneurysm may be done in one of three ways. A metal mesh “stent” is sometimes fitted over the aneurysm, preventing further dilation, or surgical repair if deemed appropriate.

In memoriam: We will miss our friend Lisa Miro. Thank you for your dedication of 30 years to the field of Diagnostic Echocardiography