Hypogastric Artery Flow Interruption Is Associated With Increased Mortality After Open Aortic Repair

Abstract

INTRODUCTION The two feared complications of pelvic flow disruption include buttock and mesenteric ischemia. Unilateral or bilateral hypogastric artery flow interruption, either from atherosclerosis or intentionally, is not well studied in open AAA repair (OAR). METHODS The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing elective open AAA repair between 2003 and 2020. Patients with data on their hypogastric arteries were stratified into two groups - patent bilaterally (normal pelvic perfusion, NPP), and unilateral or bilateral occlusion or ligation (compromised pelvic perfusion, CPP). Primary endpoints were 30-day major morbidity and mortality. RESULTS During the study period, 9.492 patients underwent elective open AAA repair - 860 (9.1%) with compromised pelvic perfusion and 8,632 (90.9%) with patent bilateral hypogastric arteries. The groups had similar cardiac risk factors (Table 1). A majority of patients in the CPP cohort had concurrent iliac aneurysms (63.3% versus 24.8%; p<.001). The perioperative mortality was significantly higher in patients with compromised pelvic perfusion (5.5% versus 3.1%; p<.001). Bilateral interruption had a higher perioperative mortality compared to unilateral interruption (7.1% versus 4.7%; p<001). The CPP group had increased rates of myocardial injury (6.7% versus 4.7%; p=.012), leg and bowel ischemia (3.5% versus 2.1%, p=.008; and 5.7% versus 3.4%, p<.001; respectively). On multivariable analysis, CPP was associated with increased mortality (OR 1.47, CI 1.14-1.88, p=.003). However, on Kaplan-Meier analysis, there was no difference on long-term survival. CONCLUSIONS CPP is associated with increased perioperative complications and higher mortality in patients undergoing OAR, with no affect on longer-term survival. Hypogastric artery occlusion or need for ligating these vessels likely signifies presence of more complex disease, and warrants careful technique and appropriate patient selection. The two feared complications of pelvic flow disruption include buttock and mesenteric ischemia. Unilateral or bilateral hypogastric artery flow interruption, either from atherosclerosis or intentionally, is not well studied in open AAA repair (OAR). The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing elective open AAA repair between 2003 and 2020. Patients with data on their hypogastric arteries were stratified into two groups - patent bilaterally (normal pelvic perfusion, NPP), and unilateral or bilateral occlusion or ligation (compromised pelvic perfusion, CPP). Primary endpoints were 30-day major morbidity and mortality. During the study period, 9.492 patients underwent elective open AAA repair - 860 (9.1%) with compromised pelvic perfusion and 8,632 (90.9%) with patent bilateral hypogastric arteries. The groups had similar cardiac risk factors (Table 1). A majority of patients in the CPP cohort had concurrent iliac aneurysms (63.3% versus 24.8%; p<.001). The perioperative mortality was significantly higher in patients with compromised pelvic perfusion (5.5% versus 3.1%; p<.001). Bilateral interruption had a higher perioperative mortality compared to unilateral interruption (7.1% versus 4.7%; p<001). The CPP group had increased rates of myocardial injury (6.7% versus 4.7%; p=.012), leg and bowel ischemia (3.5% versus 2.1%, p=.008; and 5.7% versus 3.4%, p<.001; respectively). On multivariable analysis, CPP was associated with increased mortality (OR 1.47, CI 1.14-1.88, p=.003). However, on Kaplan-Meier analysis, there was no difference on long-term survival. CPP is associated with increased perioperative complications and higher mortality in patients undergoing OAR, with no affect on longer-term survival. Hypogastric artery occlusion or need for ligating these vessels likely signifies presence of more complex disease, and warrants careful technique and appropriate patient selection.