Aspartate transaminase to platelet ratio index and Model for End-Stage Liver Disease scores are associated with morbidity and mortality after endovascular aneurysm repair among patients with liver dysfunction.

BACKGROUND

Liver cirrhosis dramatically increases morbidity and mortality after open surgical procedures and is often a contraindication to open repair of abdominal aortic aneurysms. However, limited data have evaluated the effect of liver disease on outcomes after endovascular repair of aortic aneurysms.

METHODS

The National Surgical Quality Improvement Program was used to evaluate all nonemergent endovascular aneurysm repairs (EVARs) from 2005 to 2016. The aspartate transaminase to platelet ratio index is a sensitive, noninvasive screening tool used to screen for liver disease and was calculated for all patients. A value >0.5 was used to identify those with significant liver fibrosis. Demographics, comorbidities, and 30-day outcomes were then compared between patients with and patients without fibrosis. Additional analysis was then completed to assess the effect of increasing Model for End-Stage Liver Disease (MELD) score on 30-day outcomes. Multivariable regression was used to account for differences in baseline factors.

RESULTS

EVAR was performed on 18,484 patients including 2286 with liver fibrosis and 16,198 without. Patients with liver fibrosis had an increased 30-day mortality (1.5% vs 2.4%; P < .01) and significantly higher rates of major morbidities including return to the operating room, pulmonary complications, transfusion, and discharge other than home. After multivariable analysis, patients with liver fibrosis had a significant increase in 30-day mortality (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.1-2.1), return to the operating room (OR, 1.5; 95% CI, 1.2-1.8), pulmonary complications (OR, 1.6; 95% CI, 1.2-2.0), transfusion (OR, 1.7; 95% CI, 1.5-2.0), and discharge other than home (OR, 1.5; 95% CI, 1.3-1.8). In further analysis, mortality also increased in a stepwise fashion with increasing MELD score (MELD <10, 1.3%; MELD 10-15, 2.3%; MELD >15, 4.7%; P < .01), as did major complications (MELD <10, 7%; MELD 10-15, 11%; MELD >15, 15%; P < .01). These increases persisted in adjusted analysis.

CONCLUSIONS

Liver fibrosis significantly increases mortality and major morbidity after EVAR. The aspartate transaminase to platelet ratio index and MELD score should be used for preoperative risk stratification. Moreover, current 30-day morbidity and mortality rates among patients with MELD scores >10 exceed 5%, which is higher than the annual rupture risk for aneurysms <6 cm. Therefore, an increased size threshold of >6 cm may be warranted before EVAR in patients with liver fibrosis.