Impact of Vascular Anomalies on Pancreatoduodenectomy Procedure

BACKGROUND: One of the critical steps during pancreatoduodenectomy (PD) procedure lies in identifying the complicated vascular anatomy of the resected area. The blood supply usually stems from branches of the celiac and the superior mesenteric arteries. However, only in 55-79% of surgeries, the anatomy of the blood vessels encountered by the surgeon is considered normal, while in the remaining cases, there are vascular variations that make these surgeries even more challenging. Any change or deviation from the known surgical course of PD makes surgery difficult and can result in an increase in intra/postoperative complications. In order to reduce difficulties encountered during PD, as well as reducing complication rates and improving surgical outcomes, a preliminary design, which includes preoperative identification of anatomical variations, is needed. The most accurate and accessible tool for identifying such variations is computed tomographic angiography (CTA). The aim of this retrospective study is to assess the prevalence of vascular anomalies encountered during PD, and examine whether there is an association between these anomalies and intra/postoperative morbidity and mortality. METHODS: A retrospective study over 5 years was performed at the HPB and Surgical Oncology Unit, Rambam Health Care Campus, Haifa, Israel. The charts of all patients submitted to PD were reviewed, and all patients with vascular anomalies were included. The types of anatomical variant as well as other information were collected. For statistical purposes, the group of patients with vascular anomalies was compared to a control group with identical demographic characteristics. A statistical analysis on possible association between vascular anomalies and intra/postoperative complications (mainly bleeding) was performed. RESULTS: During the aforementioned period, 202 patients underwent PD, and in 41 (20.3%) vascular anomalies were identified. The majority of these patients (32/41) had single anatomical variant, where two and three anatomical variants were identified in seven and two patients, respectively. The most common vascular anomaly was replaced right hepatic artery, noticed in 34 patients (83%). The most common indication for PD for both groups (anatomical variant and control group) was pancreas adenocarcinoma (56%). Intraoperative complication, in the form of bleeding, developed in 6/41 patients (14.6%) of the anatomical variant group and none in the control group. Postoperative complication rates, including post- pancreatoduodenectomy hemorrhage (PPH), postoperative pancreatic fistula (POPF), intra-abdominal abscess and wound infection were almost identical for both groups. One case of death within 30 days occurred, and it was in the anatomical variant group. CONCLUSIONS: Anatomical vascular anomalies are a common variant encountered during PD, with RRHA being the most common. Although postoperative morbidity and mortality are not affected by the presence of these anomalies, intraoperative bleeding rate is higher in this specific group, thus; a preoperative diagnosis by means of CTA is mandatory.