Because HD patients possess many coronary risk factors, including advanced age, hypertension, and diabetes, the coronary vascular pathology of HD patients is characterized not only by diffuse coronary artery lesions extending across several branches but also by the progression of atherosclerosis as a result of lipid metabolism abnormalities and severe calcification as far as the media. These pathological features develop as a result of calcium/phosphorus metabolism abnormalities.

Marked systemic atherosclerosis is also characteristic of HD patients, and calcifications and obstructive lesions of the aorta, peripheral arteries in the legs, and the carotid arteries are frequent additional complications.

Left ventricular hypertrophy is also frequently evident in HD patients, probably as a result of prolonged hypertension, and is one cause of left ventricular failure. Even if left ventricular function initially appears to be maintained, patients can easily succumb to left heart failure.

Long-term follow-up results for HD patients after CABG are comparatively poor compared with patients without complications. In particular, 5-year survival after CABG in HD patients with diabetes is below 50 % [4, 5]. It is important that treatment strategies be established that take into account the fact that such patients have a large number of risk factors that may affect their prognosis, not only in terms of ischemic heart disease but also other conditions, such as cerebrovascular disturbance in the context of systemic atherosclerosis and susceptibility to infection associated with compromised immune function.

OPCABG is more frequently performed in Japan than in Europe and the United States. This is because of the high rate of use of PCI in Japan, meaning that patients who undergo CABG are frequently high-risk individuals, and surgeons are working in an environment where OPCABG is used proactively with the aim of avoiding perioperative complications. In Japan, where 65 % of isolated CABG procedures are performed off pump, OPCABG may be actively used to treat high-risk HD patients.

Numerous studies have found that OPCABG is advantageous for HD patients from the standpoint of perioperative mortality [6–8]; however, there is concern that fewer branches can be bypassed in OPCABG, resulting in poorer long-term results due to incomplete revascularization. According to Dewey et al. [9], although operative mortality in OPCABG is good, long-term survival for nondiabetic patients is better when ONCABG is used. The cause of these poor long-term results is the fact that the mean number of branches bypassed in ONCABG is 3.3, compared with 2.4 in OPCABG. In OPCABG it is difficult to perform bypasses to the circumflex branch region, meaning that revascularization is incomplete.

However, surgeons who are highly skilled at performing OPCABG are capable of achieving an equivalent level of revascularization to that attainable with ONCABG [10].

Beckermann’s analysis of the United States Renal Disease System (USRDS) database [11] clearly shows the advantages of performing OPCABG. As OPCABG does not entail the risks of excessive fluid balance and inflammatory cytokine production that are involved in extracorporeal circulation, it may be a particularly beneficial surgical procedure for high-risk HD patients.

Reports from Japanese institutions have also shown the usefulness of OPCABG for HD patients [12–14].

The choice between ONCABG and OPCABG when performing CABG is made according to the policies of individual institutions, but in some cases, it is absolutely necessary to perform OPCABG in order to avoid the risks of extracorporeal circulation. In institutions that use conventional ONCABG as the basic surgical procedure for CABG, it may be difficult to use OPCABG only for high-risk patients, and proficiency in OPCABG must be acquired.