Endovascular Aortic Repair Follow up Protocol Based on Contrast Enhanced Ultrasound Is Safe and Effective.

OBJECTIVES

The aim of this study was to define the safety and effectiveness of a contrast enhanced ultrasound (CEUS) based follow up for endovascular aortic repair (EVAR) surveillance at a mid-term period (4 years).

METHODS

At the tertiary referral centre EVAR surveillance was based on plain abdominal radiograph and duplex ultrasound (CDU), with computed tomography angiography (CTA) reserved for any non-diagnostic imaging during the period 1999-2011 (Group A). From 2012, CEUS was performed when (a) any endoleak was detected at CDU, (b) sac growth > 5 mm within 6 months, and routinely for (c) patients with renal insufficiency (above Stage 3 chronic kidney disease), or (d) iodine contrast allergy (Group B).

RESULTS

A total of 880 patients (mean age 75.6 ± 8.4 years; 824 male) who underwent EVAR between 1999 and 2015 and with a minimum of 1 year follow up were included. Six hundred and nineteen patients were in Group A (70%) and the remaining 261 in Group B (30%). Median follow up was 48 months (interquartile range 24-84). During the study period 318 CEUS scans were performed with no related complications. Indications for CEUS were the following: (a) 160 (50%) endoleak presence, (b) 34 (11%) significant sac expansions, (c) 91 (29%) renal insufficiency (Stage 3 or above CKD), and 33 (10%) iodine contrast allergies. CEUS was compared with CTA, with additional confirmation by angiographic and operative findings in the case of repair in the first 100 patients. CEUS had 100% sensitivity and 100% specificity in classifying endoleaks. No differences in endoleak, re-interventions and sac shrinkage percentage were seen between the two groups at 4 years. A 4 year analysis of CTA use found a 90% reduction with the introduction of CEUS.

CONCLUSIONS

The introduction of a CEUS based protocol for EVAR follow up was safe and effective and it was similar to the previous CTA based follow up protocol with regard to identification of endoleaks in a mid-term period. Moreover, CEUS allowed for 90% reduction of CTA, thereby decreasing radiation exposure for patients.