Influence of respiratory cycle on proximal renal artery motion: an angiographic study in patients undergoing endovascular aneurysm repair.

Background: The purpose of our study was to evaluate the influence of respiratory cycle on proximal renal artery (RA) motion in twenty consecutive patients with abdominal aneurysm and the potential impact on endograft deployment during endovascular aneurysm repair (EVAR).

Methods: Prior to the device introduction, a preoperative angiography to define the location of the RAs was performed by a calibrated pigtail catheter. A measuring tape on the table served as the reference point for all measurements. Images of RA levels were acquired during expiration (E) and inspiration (I) cycles. In order to have homogenous comparative values for each patient during inhalation, the anaesthesiologist maintained a controlled inspiration with a uniform pressure of 30 cm of water. Motion of the RAs was defined as the changes in distance between E and I measures, adjusted to the calibrated pigtail.

Results: The median right proximal RA motion was 3.0 mm (IQR 2.4 mm; range: 0 to 5.6 mm). The median left proximal RA motion was 3.1 mm (IQR 2.2 mm; range: 0.54 to 5.6 mm). The current results demonstrate the proximal RAs motion during breath with a median magnitude of 3 mm, without significant differences between both RA (P = .83).

Conclusion: Our data confirm the RAs motion during respiratory cycle. More than the predictive absolute value of the RA motion between inspiratory and expiratory phases, it is the motion itself which is important. This unrecognized condition, even if it interests only a minority of patients, could potentially have clinical disastrous consequences : potential stenosis or covering of RAs.