Both patients in this report had a follow-up of 8 years. The rst patient had an abdominal aor­tography and study of the lower extremities for ischemic lesions of the left foot. The second patient in this report had subsequent occlusion of the graft (retrograde bypass graft), but the exact time of the occlusion cannot be determined.

One of the most devastating complications of CMI is mesenteric arterial thrombosis resulting in acute mesenteric ischemia (AMI). Acute arte­rial thrombosis superimposed on preexisting severe atherosclerotic disease represents that sec­ond most common cause of AMI as up to 20% of AMI patients have demonstrated a history of CMI, with symptoms of abdominal pain, food avoidance, or weight loss [8, 9]. For patients who progress from CMI to AMI, the classic symptom includes “abdominal pain of out proportion to exam” for early mesenteric ischemia. Yet this may be absent in 20–25% of cases, depending on the cause and timing of presentation [10]. Until transmural ischemia has developed, there is rela­tively little peritoneal irritation, thus minimizing tenderness to palpation. Further, in contrast to patients who develop AMI secondary to an embolic event, patients who develop acute on chronic mesenteric ischemia often have bowel infarction that is more insidious in onset because extensive collaterals are able to maintain viability until there is nal closure of a critically stenotic vessel or collateral. As such, a high index of sus­picion in the setting of a compatible history and physical examination serves as a cornerstone of prompt treatment. Regarding the diagnostic algo­rithm for AMI, there has been a paradigm shift. Older models advocated early and aggressive use of diagnostic arteriography; however, this has now largely been supplanted with computed tomographic angiography (CTA) when AMI is suspected. The use of ultrafast multidetector CTA (MDCTA) for the evaluation of both acute and chronic mesenteric ischemia is well described [11]. The widespread availability of the newest generation of CT scanners has advanced the diag­nostic algorithm for AMI, providing a signicant amount of information about the central arterial and venous circulations.

including endarterectomy, antegrade arterial bypass, retrograde arterial bypass, or hybrid revascularization. For arterial bypass in an emer­gent setting, a single bypass to the SMA is all that is required, and graft orientation is inuenced mainly by the degree of atherosclerosis and occlusive disease present in the inow vessels and by the overall lie of the graft. As such, a ret­rograde graft orientation is common with its ori­gin from the right common iliac artery in a “lazy C” conguration. This avoids any aortic clamp­ing with the increased hemodynamic stress and usually provides a good lie to prevent kinking. Alternatively, a hybrid open retrograde mesen­teric stenting can be performed for acute athero­sclerotic SMA thrombosis. This technique combines a less invasive mesenteric revascular­ization without compromising important general surgical principles. Recent small single center studies have demonstrated acceptable outcomes with a hybrid approach [7]. A solely endovascu­lar treatment modality is not generally applied due to the potential need for bowel resection. As described previously, operative bypass to the SMA is traditionally required owing to the extent of disease. In recent years, mortality after revas­cularization for AMI has declined from 50% in the 1990s to 30% in the 2000s; however, mortal­ity remains high in patients with AMI even after successful surgical revascularization [3]. Factors associated with increased mortality were renal insufciency, age older than 70years, metabolic acidosis, symptom duration, and need for bowel resection during second-look operations [12]. Lastly, owing to high recurrence rates, both short­and long-term follow-up is critical for maintain­ing the patency of open and especially endovascular revascularized vessels [13].

lethal condition. The technical issues are well delineated and outcomes overall good.