P1.01 PULSE WAVE VELOCITY: HOW TO ASSESS THE DISTANCE?

Abstract

Objective: Pulse wave velocity (PWV) is accepted as the standard technique to assess aortic stiffness. While the carotid-femoral transit time can be assessed with high accuracy, the measurement of the aortic length is, however, less accurate. Several approaches for measuring aortic length over the body-surface exist, all of which are measured with a tape measure, hence introducing errors over the curved body surface. Design and method: We compared eight different body-surface distances with the aortic path length as determined from Magnetic Resonance (MR)-images. 12 healthy volunteers (aged 23 to 39 years) were imaged from carotid to femoral artery. Body surface measurements were done with an antropometer and tape measure. Aortic path length along the luminal centreline was determined from MR-images using custom built Matlab-based software. Results: Only two body surface measurements were close to the MR-derived aortic path length. Total distance between carotid and femoral artery minus the distance between carotid artery and sternal notch was 2.1±3.7cm (5.3±8.9 %) larger than the MR-derived aortic path length. The distance between the suprasternal notch and the femoral artery minus the distance between the carotid artery and the suprasternal notch was 1.1±2.7cm (2.4±6.0 %) smaller than the MR-derived aortic path length. Conclusions: For assessment of PWV, aortic length can be estimated by the total distance between carotid and femoral artery minus the distance between carotid artery and sternal notch or by the distance between the suprasternal notch and the femoral artery minus the distance between the carotid artery and the suprasternal notch.