Endoleaks after endovascular aneurysm repair lead to nonuniform intra-aneurysm sac pressure.
OBJECTIVE
This was a study of intra-aneurysm sac pressures in patients who presented with endoleaks after endovascular repair (EVAR) of abdominal aortic aneurysms (AAA).


METHODS
Twenty-five patients (18 men, 7 women) with endoleaks, age (IQR 68 to 80), underwent 31 direct intra-aneurysm sac pressure measurements, DISP at 16 months after EVAR (IQR, 14 to 26 months). Diameter of AAA was 59 mm (IQR, 52 to 67 mm). Six patients underwent DISP twice. Tip-pressure sensors were used through direct translumbar puncture of the AAA except in three patients (transabdominal puncture in 2; endoluminal in 1). Mean pressure index (MPI) was calculated between simultaneously registered intra-aneurysm sac and systemic pressures. Values presented are medians with interquartile range (IQR).


RESULTS
Type I endoleaks (n = 1) showed MPI of 93% in the nidus and 62% in the thrombus. Type II endoleaks were associated with lower MPIs in the thrombus (35%; IQR 24% to 38%) when AAAs shrank (n = 4) compared with when the AAAs remained unchanged (n = 11; MPI, 78%; IQR, 47% to 85%) or expanded (n = 6; MPI, 74%; IQR, 58% to 87%; P = .019). The nidus of type II endoleaks (MPI, 79%; IQR, 70% to 90%) had higher pressure than the thrombus (45%, IQR, 34% to 85%; P = .047; n = 7). Successful embolization of type II endoleaks led to AAA shrinkage (n = 3; MPI reduction, 13% to 31%) or diameter stability (n = 3; unchanged MPIs, 37% to 44%). Type III endoleaks (n = 3) had MPIs in the thrombus of 33% to 70%.


CONCLUSIONS
Endoleaks after EVAR pressurize the AAA sac nonuniformly, with higher, near-systemic, pressure in the endoleak nidus compared with the thrombus. Nevertheless, type II endoleaks in shrinking AAAs have lower intra-sac pressure than expanding or stable aneurysms, and successful endoleak embolization reduces pressure.
Department of Vascular Diseases Malmö-Lund and Endovascular Centre, Malmö University Hospital, Lund University, Malmö, Sweden. nuno.dias@med.lu.se
Nuno V
NV
Dias
Krassi
K
Ivancev
Timothy A
TA
Resch
Martin
M
Malina
Björn
B
Sonesson
D000368:Aged; D015901:Angiography, Digital Subtraction; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000295:instrumentation*; D004621:Embolization, Therapeutic; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011182:Postoperative Care / Q000295:instrumentation*; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy; D011312:Pressure; D011475:Prosthesis Failure; D015607:Stents; D013997:Time Factors; D036542:Tomography, Spiral Computed; D014160:Transducers, Pressure; D016896:Treatment Outcome