Multivessel revascularization is generally recommended for patients who are undergoing open surgical revascularization for symptomatic chronic mesenteric ischemia (Table 21.2). This can be accomplished via antegrade bypass originating from the supraceliac aorta to the celiac and superior mesenteric arteries, retrograde bypass to multiple mesenteric vessels originating from the infrarenal aorta or iliac artery, or transaortic endarterectomy.

Improved patency and freedom from recurrent symptoms with multivessel revascularization has been demonstrated directly and indirectly in several nonrandomized case series. Early experience from the Mayo Clinic was described by Hollier et al. who reported a 20 year experience with operation for chronic mesenteric ischemia [3]. They noted a 50 % recurrence rate when one of the three mesenteric arteries was reconstructed, compared to an 11 % recurrence rate if all diseased vessels were reconstructed. Recurrence correlated inversely with number of visceral arteries that were revascularized. A subsequent study described a later experience from the same institution and confirmed these findings. This study included antegrade bypasses (of which there were none in the Hollier study) and found improved graft patency and patient survival in those undergoing three vessel repair compared to those who had two or one vessel repair (patency, 94 % vs. 54 % vs. 0 % for three, two, and one vessel revascularization; survival, 73 % vs. 57 % vs. 0 %) [4]. This study, like the earlier Mayo Clinic experience, defined symptomatic graft failure as the endpoint, so the true patency data are not known.

Another study of 85 patients with open mesenteric revascularization from Cleveland Clinic also confirmed improved outcomes with “complete” revascularization compared to “incomplete” [5]. In this review, 25 % of patient had all affected mesenteric vessels treated while 75 % had “incomplete” revascularization. This study attempted to evaluate recurrence in terms of both symptoms as well as objective evaluation of patency by Duplex ultrasound, CT angiography, or intra arterial angiography with 64 % of their patients having at least one of these studies in the postoperative period. They noted that all patients who died from mesenteric ischemia in the follow up period had “incomplete” revascularization and more patients with “incomplete” revascularization had recurrent symptoms at 5 years and had a lower overall survival rate. However, this improvement in freedom from symptoms and survival came at an expense of increased perioperative complications.

In a study of redo mesenteric bypass, Schneider noted that significantly fewer vessels were revascularized at the original operation in patients who were undergoing reoperation for recurrent mesenteric ischemia compared to a nonrecurrent group [6]. A small recent study reporting single vessel revascularization noted that three of nine patients developed restenosis or graft stenosis in the follow up period [7]. And finally, Oderich attempted a meta-analysis of combined data available in the literature and found a 14 % symptom recurrence rate with single vessel reconstruction compared to 5 % when multiple vessels were reconstructed [8]. This type of analysis is clearly limited by the differences in patient population, operation types, and endpoints reported in the various included studies.

Several additional studies have examined whether multivessel revascularization results in better patency and freedom from symptoms without finding a clear difference in outcomes. Park and colleagues reevaluated the Mayo Clinic experience in 2002 [10], and found no difference in patency or symptom free survival based on number of vessels revascularized. However, their series included a minority of single vessel revascularizations (19/98 patients). They continued to recommend multivessel revascularization based on equivalent results, to achieve a “margin of safety” in these challenging patients. Kruger also found no difference in patency between single and multivessel revascularization, but continued to recommend multivessel reconstruction based on the nature of outcomes when single vessel grafts occluded [13].

Several authors, including two series from the Oregon group, continue to support single vessel mesenteric revascularization. An earlier study by Gentile et al. demonstrated 89 % graft patency and 82 % survival rates at 4 years with single vessel reconstruction [11]. Foley and colleagues reported a later experience from the same group, continuing to support single vessel revascularization with a 9 year primary assisted patency rate of 79 % and 5 year patient survival rate of 61 % [12]. However, almost half of the patients included in this series had acute mesenteric ischemia, which represents a different circumstance than a chronic presentation.

Additional indirect data supporting multivessel revascularization can be extrapolated from studies examining open surgical versus endovascular procedures for chronic mesenteric ischemia. Kougias and colleagues examined surgical and endovascular mesenteric revascularization. They found significantly better freedom from recurrent symptoms in the surgical revascularization group, 64 % of which had two vessel reconstruction, compared to the endovascular group, 21 % of which had two vessel reconstruction. They attributed the improved outcomes of the surgical group to higher incidence of two vessel revascularization [14]. Oderich noted better patency with open revascularization (77 % of whom had multiple vessels treated) compared to an endovascular approach (75 % of whom had a single vessel treated) [9]. However, when they examined single versus two vessel revascularization separately in the open and endovascular groups, they were not able to find a significant difference, potentially due to the limited number of patients in the groups. Kasirajan found similar patency but greater recurrence of symptoms in patients treated via an endovascular approach compared to open surgery [15]. Again, the patients in the endovascular group had fewer vessels treated per patient compared to the open surgical group (1.1/patient vs. 1.5/patient), indirectly supporting multivessel reconstruction.

Another rationale supporting multivessel reconstruction is the idea that the consequences of graft occlusion of one of multiple revascularized vessels may not be as severe as if a single graft occludes in patients who typically have multivessel disease. Based on the principle that at least two mesenteric vessels must be diseased to result in symptoms, maintaining patency of one of two reconstructed vessels may be sufficient and provide a “margin of safety” as Park and colleagues have advocated [10]. They noted that symptoms only occurred if both limbs of a bifurcated graft became stenotic or occluded or if a single graft to the SMA developed recurrent disease. In 7 patients with stenosis in one of multiple vessels revascularized, no symptoms occurred. Kruger also noted that patients with multivessel reconstruction in whom only one vessel developed recurrent disease did not manifest symptoms, whether this occurred in the acute postoperative setting or in long term follow up [13].

The type of symptom presentation with recurrent disease may also differ depending on whether single or multiple vessel revascularization is utilized. Occlusion or stenosis of a single revascularized vessel in the setting of typical multivessel disease may be more likely to result in acute symptoms, which are commonly fatal. In the original Oregon experience, two of three patients with late graft failure after a single vessel revascularization died [11]. Similarly, in Mateo’s series from the Cleveland Clinic, all patients who died from mesenteric ischemia were ones who had undergone “incomplete” revascularization [5]. Giswold reports another series of patients with recurrent mesenteric ischemia after an original single vessel mesenteric bypass of which almost half presented with acute symptoms [16]. Certainly, recurrence of disease in the absence of mesenteric ischemia symptoms, or at the least, avoidance of acute mesenteric ischemia presents a more manageable situation than acute symptomatic recurrence, and in this situation, redo procedures may not be necessary at all, or can be attempted minimally invasively.

Initial multivessel revascularization may help to avoid subsequent redo mesenteric bypass by improving patency or preventing symptoms in the setting of recurrent disease. While some of the patients with recurrence may be able to be managed minimally invasively with an endovascular approach, many patients with recurrence will require reoperation due to the location and severity of the disease. Reoperation for mesenteric ischemia is a more difficult operation that is associated with significant morbidity and mortality. While several studies of reoperation for mesenteric ischemia have been unable to find a significant difference in morbidity and mortality compared to initial operation, these series had very limited numbers (under 50 patients). Most of them failed to take into account the group of one third to one half of the patients who presented with acute symptoms, which was almost universally fatal [6, 16, 17].