Intraoperative sac pressure measurement during endovascular abdominal aortic aneurysm repair.

ABSTRACT

PURPOSE: Intraoperative sac pressure was measured during endovascular abdominal aortic aneurysm repair (EVAR) to evaluate the clinical significance of sac pressure measurement. METHODS: A microcatheter was placed in an aneurysm sac from the contralateral femoral artery, and sac pressure was measured during EVAR procedures in 47 patients. Aortic blood pressure was measured as a control by a catheter from the left brachial artery. RESULTS: The systolic sac pressure index (SPI) was 0.87 +/- 0.10 after main-body deployment, 0.63 +/- 0.12 after leg deployment (P < 0.01), and 0.56 +/- 0.12 after completion of the procedure (P < 0.01). Pulse pressure was 55 +/- 21 mmHg, 23 +/- 15 mmHg (P < 0.01), and 16 +/- 12 mmHg (P < 0.01), respectively. SPI showed no significant differences between the Zenith and Excluder stent grafts (0.56 +/- 0.13 vs. 0.54 +/- 0.10, NS). Type I endoleak was found in seven patients (15%), and the SPI decreased from 0.62 +/- 0.10 to 0.55 +/- 0.10 (P = 0.10) after fixing procedures. Type II endoleak was found in 12 patients (26%) by completion angiography. The SPI showed no difference between type II endoleak positive and negative (0.58 +/- 0.12 vs. 0.55 +/- 0.12, NS). There were no significant differences between the final SPI of abdominal aortic aneurysms in which the diameter decreased in the follow-up and that of abdominal aortic aneurysms in which the diameter did not change (0.53 +/- 0.12 vs. 0.57 +/- 0.12, NS). CONCLUSIONS: Sac pressure measurement was useful for instant hemodynamic evaluation of the EVAR procedure, especially in type I endoleaks. However, on the basis of this small study, the SPI cannot be used to reliably predict sac growth or regression.