Severe correctable CAD was identified in 34 % of patients with abdominal aortic disease [19, 20]. CAD is the leading cause of postoperative death following abdominal aortic aneurysm (AAA) repair [21]. The 5-year mortality rate of myocardial infarction in patients who had preoperative evidence of heart disease is four times higher than that in patients without CAD [22]. Therefore, cardiac evaluation and coronary revascularization have been recommended, if indicated, to be carried out before AAA repair [23–26]. Generally, CAD is treated first, followed by AAA repair, and improvements in CABG and percutaneous coronary intervention (PCI) before AAA operation have clearly decreased both early and late mortality [27, 28]. Single-vessel CAD can be treated by PCI, and some two-vessel diseases may be treated in accordance with guidelines of the treatment for stable ischemic coronary disease. However, there are some considerable issues after PCI. PCI requires repeated treatment more often than does CABG in early and long-term observations [29, 30]. In addition, if a drug-eluting stent or even a bare metal stent is implanted in the coronary artery, the patient requires heavy anticoagulation therapy for 3 months or more. In this situation, the patients have to wait for a long time, may experience heavy postoperative bleeding, and may require transfusion and re-exploration. In contrast, conventional CABG surgery with CPB also requires patients to wait until they recover. The duration varies depending on each individual patient. In general, after using CPB, the waiting time would be 3 weeks or more. One report says 6 weeks are needed for complete recovery after using CPB [31]. For all these reasons, OPCAB can shorten the waiting time for the second stage. Another reason is that major open chest or abdominal surgery could accelerate the enlargement of the aortic aneurysm. In addition, surgery using CPB may have a direct impact on aortic aneurysm dilation, causing further wall weakening and decreasing tensile strength, because CPB itself induces various inflammatory responses.

However, when a patient has some symptoms of AAA or when the AAA is critically enlarged, simultaneous surgery should be planned. OPCAB is superior to conventional CABG [32, 33] in simultaneous surgery with AAA repair. However, in cases of asymptomatic AAA and CAD, whether a simultaneous operation is better than a staged operation is controversial, and many surgeons are concerned over wound infection, including mediastinitis, bleeding, and prolonged ventilation-induced pneumonia, excepting the cost–benefit ratio of medical care. In not only simultaneous operation of CABG and AAA repair but also the other types of simultaneous surgeries, the outcome depends on the surgeon’s skill.

In addition, currently, endovascular aortic replacement (EVAR) is widely available, although indication for EVAR is strict in terms of the morphology. The combination strategy of OPCAB and EVAR will soon be commonly adopted.

As mentioned earlier, simultaneous operations should be considered primarily. However, therapeutic priority should be judged with precise assessments of the severity and urgency of both cancer and CAD, and then simultaneous or staged procedures should be selected.