[Retrograde aortomesenteric loop bypass behind the left renal pedicle ("French bypass") in the treatment of acute and chronic mesenteric ischemia. Clinical experiences and long-term follow-up in 27 patients]. / Der retrograde aorto-mesenteriale Bypass mit links retrorenalem Verlauf ("französischer Bypass") bei der Behandlung der akuten und chronischen viszeralen Ischämie. Klinische Erfahrung und Langzeitverlauf bei 27 Patienten.

ABSTRACT

BACKGROUND: In 2001 Leschi et al. published a new method to improve perfusion of the superior mesenteric artery (SMA) in operative therapy of acute and chronic visceral ischemia. They presented a retrograde aorto-mesenteric bypass following an arcuate course behind the left renal pedicle. Due to the intricate correct anatomic description of this vascular reconstruction this loop bypass was named the "French bypass". PATIENTS AND METHODS: In our department 84 patients underwent surgery because of an acute or chronic visceral ischemia between January 2002 and December 2007. Out of these patients 27 received a "French bypass". The pre-, intra-, and postoperative data were collected from the patient hospital files retrospectively. The follow-up consisted of a review of the patient history and clinical findings in an outpatient setting, combined with a duplex sonography of the visceral arteries. RESULTS: The group of 27 patients had an average age of 55.0 years (range 29-81 years) and consisted of 21 women (78.6 %) and 6 men (21.4 %). The cardinal symptom of all patients was abdominal pain of variable intensities. 14 patients complained about an increased pain post ingestion (abdominal angina) and 12 patients about an involuntary loss of weight. Bypass material was autologous saphenous vein in 18 patients (66.7 %) and in 9 patients (33.3 %) an 8-mm ring-enforced PTFE prosthesis. Apart from 10 patients who only received the French bypass, we performed comprehensive visceral revascularisations in 12 patients. Overall hospital mortality was 18.5 %; 4 out of the 5 deceased patients had undergone surgery due to acute visceral ischemia. The mortality of patients with acute visceral ischemia was 30.8 % and of patients with chronic visceral ischemia 7.1 %. Eight patients had a revision before -discharge from hospital (surgery n = 6, interventional n = 2). Primary and secondary patencies of the bypasses of the surviving patients were 54.6 % (12 out of 22 patients) and 81.8 % (18 out of 22 patients), respectively. Concerning the end-point "freedom from abdominal complaints" 14 out of 27 patients (51.9 %) benefited after a mean follow-up of 38.9 months (range 3-84 months), 7 patients each in the acute and chronic visceral ischemia group. CONCLUSIONS: The implantation of a "French bypass" represents a good option to reconstruct the SMA, combining the advantages of ante- and retrograde visceral bypasses. Furthermore this -bypass procedure allows to reconstruct distal segments of the -superior mesenteric artery in cases when long distance and peripheral stenosis impeded local thromendarterectomy. Perioperative morbidity and mortality are acceptable when the acute clinical situation is taken into account. The long-term benefit for the patients with regard to the prevention of intestinal ischemia and also the freedom from complaints is high.