Contrast-Enhanced Transthoracic Aortic Ultrasonography for Endoleak Detection After Thoracic Endovascular Aortic Repair

Pocket-Size Mobile Echocardiographic Screening of Thoracic Aortic Aneurysms in Hypertensive Patients

BACKGROUND

Patients with hypertension may develop a thoracic aortic aneurysm (TAA) that can be asymptomatic but potentially life-threatening. We sought to assess the prevalence of asymptomatic TAA among hypertensive patients with a point-of-care screening program using pocket-size mobile echocardiographic (PME) devices.

METHODS

We prospectively performed transthoracic aortic ultrasound using a PME device on patients attending our hypertension clinics between June 2016 and July 2018. The echo examinations were performed by a research fellow to obtain aortic diameter measurements including the aortic sinus, sinotubular junction, ascending aorta, aortic arch, and descending thoracic aorta through various standard echo views. Images were stored on the PME and transferred to a desktop computer for measurements and further statistical analysis.

RESULTS

During the study period 1529 hypertensive patients (mean age, 62 years [range, 30-85]; 824 men) were recruited. The prevalence of TAA (defined as maximum aortic diameter ≥ 4.5 cm and/or >50% larger than the diameter of the adjacent normal aorta) in our study population was 7.5% (115/1529). Multiple logistic regression analysis identified male gender (odds ratio, 2.120; P < .001) and older age (odds ratio, 1.031; P < .001) as independent factors associated with TAA.

CONCLUSIONS

Silent TAA is common among hypertensive patients in Hong Kong. We found the PME device to be effective in detecting TAA in a clinic setting. Such an approach may be useful for early detection of TAA among at-risk patients, allowing aggressive blood pressure control and early surgical intervention to prevent catastrophic complications.

Intraoperative contrast-enhanced ultrasound examination for endoleak detection after complex and infrarenal endovascular aortic repair

OBJECTIVE

The aim of this pilot study was to evaluate intraoperative contrast-enhanced ultrasound (iCEUS) examination for endoleak (EL) detection after complex endovascular aortic repairs (EVAR) in comparison with the standard angiographic completion control.

METHODS

Twenty-one patients (16 male; median age, 73 years [range, 54-81 years]) who underwent single-stage EVARs at our center between October 2016 and October 2018 were included prospectively. The procedures comprised fenestrated and/or branched EVAR (n = 14; 66%), infrarenal EVAR (n = 5; 24%), infrarenal EVAR with bilateral iliac side branch implantation (n = 1; 5%), and infrarenal EVAR with occluder implantation into the internal iliac artery (n = 1; 5%). The used endografts included 14 custom made devices (Cook, Australia Pty Ltd, Brisbane, Australia, n = 6; Vascutek Terumo, Glasgow, Scotland, n = 8) and seven standard infrarenal endografts (Medtronic Inc, Santa Rosa, Calif, n = 5; Vascutek Terumo, Glasgow, Scotland, n = 1; Cook, n = 1). All patients underwent an angiographic completion control for EL detection followed by iCEUS examination. The iCEUS examination was performed by the same examiner who was blinded to the angiography result. In addition to the comparison of the angiographic results to iCEUS examination, iCEUS examination was also compared with the computed tomography angiography (CTA) before discharge (median time to CTA, 5 days [range, 1-7 days]).

RESULTS

Angiography detected eight type II EL, defining the EL origin in four cases. In addition to detecting all of those eight EL, iCEUS examination revealed eight more type II EL not seen on angiography (P = .002) and allowed a definition of the EL origin in all cases. CTA before discharge showed a persistence of only 5 of the 16 type II EL detected by iCEUS examination (31%, P = .002).

CONCLUSIONS

An iCEUS examination can be used as another adjunct to decrease exposure to contrast agent and radiation during EVAR, including complex procedures. A replacement of the completion angiography by iCEUS examination is conceivable for infrarenal EVAR, but also for endovascular type IV or type V repairs. Future studies with larger patient numbers will help to further validate iCEUS examination during complex EVAR.