Is the Use of BIMA in CABG Sub-Optimal? A Review of the Current Clinical and Economic Evidence Including Innovative Approaches to the Management of Mediastinitis

Abstract

worldwide 1,2) with annual volumes of approximately 160000 isolated cases in the US. 3) There is a significant inter-country variation with recent incidence rates ranging from 17 to 73 per 100000 inhabitants in western European countries. 4) The absolute number of CABG has fallen during the last decade due to an increase in percutaneous coronary intervention (PCI) procedures. For example, in Germany, between 2008 and 2018, isolated CABG surgery decreased from 47337 to 33999 cases (-28%). According to current international guidelines, in single-vessel disease, low-risk multi-vessel coronary artery disease or isolated left main disease PCI is generally preferred; on the other hand, CABG is usually recommended in patients with complex two-vessel disease, three-vessel disease, and/or non-isolated left main disease. 5) Bilateral internal mammary artery (BIMA) in coronary artery bypass grafting (CABG) has traditionally been limited. This review looks at the recent outcome data on BIMA in CABG focusing on the management of risk factors for mediastinitis, one of the potential barriers for more extensive BIMA utilization. A combination of pre-, intra-and postoperative strategies are essential to reduce mediastinitis. Limited data indicate that the incidence of mediastinitis can be reduced using closed incision negative-pressure wound therapy as a part of these strategies with the possibility of offering patients best treatment options by extending BIMA to those with a higher risk of mediastinitis. Recent economic data imply that the technology may challenge the current low uptake of BIMA by reducing the short-term cost differentials between single internal mammary artery and BIMA. Given that most published randomized controlled trials and meta-analyses of observational long-term outcome data favor BIMA, if short-term complications of BIMA including mediastinitis can be controlled adequately, there may be opportunities for more extensive use of BIMA leading to improved long-term outcomes. An ongoing study looking at BIMA in high-risk patients may provide evidence to support the hypothesis that mediastinitis should not be a factor in limiting the use of BIMA in CABG.

The negative pressure wound therapy for prevention of sternal wound infection: Can we reduce infection rate after the use of bilateral internal thoracic arteries? A systematic literature review and meta-analysis

“…Research evidence has shown that using IMA grafts (or ITA grafts) correlates with an elevated risk of SWI, especially when using BIMA [ 6 ]. Research by Grossi et al [ 33 ] demonstrated that having one or more IMA grafts increased the prevalence of sternal infection by 1.37% compared to patients who had no IMA graft in CABG surgery.…”

“…The literature has described numerous risk factors for SWIs [5]. The use of the bilateral internal mammary artery (BIMA) for coronary artery grafting is the most consistently reported independent risk factor for SWI, together with insulin-dependent diabetes and obesity BIMA use alone can increase the risk by 4.23 times [1,[5][6][7][8][9][10]. This has resulted in the use of BIMA in CABG, despite better long-term prognosis, which has been restricted to low-risk patients [1,6,11].…”

Total Arterial Revascularization versus Conventional Coronary Artery Bypass Grafting; A Comparative study

“…Several studies showed that RIMA was associated with better long-term outcomes compared to other conduits. 13,14 Goldstone and associates found that RIMA was associated with increased sternal wound infections and offered no advantages over the radial artery. 15 RIMA was also associated with increased operative time, bleeding, and preoperative morbidity.…”

Bilateral versus single internal mammary artery in diabetic patients: systematic review and meta-analysis

“…Therefore, the current literature remains confusing and the use of bilateral mammary arterial conduits especially in diabetics, remains rare. 1 Surgeons are hesitant to use BIMA grafts, 2 as over the past 5 years, no growth was seen in BIMA use among Medicare beneficiaries in the USA.…”