Single versus multiple internal mammary artery grafting for coronary artery bypass: 15-year follow-up of a clinical practice trial

Abstract

Background-The long-term clinical advantages of using routine multiple internal mammary artery (IMA) grafts for coronary artery bypass (CAB) are not clear. This study was designed to test the hypothesis that multiple IMA grafts would provide better 15-year outcomes when compared with single IMA and vein grafts. Methods and Results- Between 1984Between and 1987Between , 1067 consecutive patients undergoing isolated CAB were referred to 1 surgeon practicing primarily single and another surgeon maximizing multiple IMA grafts (clinical practice trial). A 207-patient subset with multiple IMAs underwent postoperative graft angiography at 1 to 32 weeks to define initial IMA patency. Patients were followed-up yearly, and the groups were analyzed as (I) surgical strategy (surgeon operating) (singleϭ413 versus multipleϭ654), (II) ultimate operation performed (singleϭ418 versus multipleϭ449), or (III) single versus multiple coronary systems revascularized with IMAs (singleϭ490 versus multipleϭ377). Advantages of this study design were that an entire referral population was examined, multiple IMAs were applied to the entire spectrum of baseline patient risk, 15-year follow-up provided a complete prognostic picture, and the subgroups were potentially comparable at baseline. In all 3 analyses, single and multiple groups were statistically similar with respect to baseline, operative, and immediate postoperative variables. Early IMA patency was 98.5% (333/338 grafts patent), validating the quality of IMA procedures. Unadjusted and adjusted 15-year outcome analyses for I, II, and III for death, myocardial infarction, percutaneous coronary intervention, redo coronary bypass, and the composite of all events identified multiple versus single as a significant predictor of outcome for the composite end point in adjusted analysis III (hazard ratioϭ0.808; 95% CI, 0.689 to 0.948; Pϭ0.009), because of a 5% to 10% absolute reduction in each of the outcome variables at 15 years. Moreover, Ͼ50% reduction in reoperation rate was observed at 15 years in every analysis. Conclusions-At 15-year follow-up, multiple IMA grafting was associated with a 19.2% adjusted risk reduction in death and cardiac events, caused by decreases in all adverse end points and fewer reoperations. These data indicate that the clinical advantages of maximizing IMA conduits are significant. Based on this information, it is suggested that multiple IMA grafting to 2 coronary systems should be applied liberally to patients with noncardiac risk profiles predictive of long-term survival.

Conduit Selection for Improved Outcomes in Coronary Artery Bypass Surgery

“…However, survival curves do not separate until several years postoperatively, which has been a consistent finding [15, 88, 89; Figure]. The demonstrated clinical advantages of BIMA grafting strategies include prolonged survival and reduced need for coronary reintervention on the basis of recurrent myocardial ischemia, including freedom from the need for coronary reintervention [15,88,90] which hold true for women as well as for men, where it has been demonstrated that use of BIMA had 3-fold improved cardiacrelated survival compared with patients who did not receive an IMA graft [91]. Reported rates of BIMA use in CABG range from 4.0% to nearly 50% depending upon several factors including the contributing authors' practice preferences and the particular patient cohort treated [19][20][21][22]92].…”

“…Most notably, the LIMA-LAD graft has been shown to be an independent predictor of survival after CABG when compared with patients not receiving LIMA-LAD [76]. In addition, using more than one IMA graft reduces the need for subsequent reintervention and prolongs survival relative to patients receiving only one arterial grafts www.intechopen.com [15,17]. Similarly, Guru et al evaluated the potential benefit of multiple arterial grafting in over 53,000 patients undergoing primary CABG between 1991 and 2001.…”

“…CABG with multiple arterial grafts have been shown to have improved graft patency, reduced need for reoperation or reintervention, and prolonged survival compared with patients undergoing CABG with one IMA and SVG [14][15][16][17]. For instance, Sabik et al reviewed a 27-year experience at the Cleveland Clinic with regard to need for reintervention after primary CABG and found that the extent of arterial grafting correlated with freedom from subsequent reintervention [18].…”

Bilateral Internal Thoracic Artery Grafting: Is It Reasonable in Octogenarians?

“…Most recent studies reported better outcomes after use of BITA grafts, especially in the younger population. [1][2][3][4][5] However, some studies reported higher rates of surgical site infection (SSI) after use of BITA grafts because of the decreased blood supply to the sternum and surrounding tissues. [6][7][8] Previous studies investigating the feasibility of using BITA grafts in elderly patients included patients aged >65 or >70 years, [9][10][11][12] but the feasibility of using BITA grafts specifically in octogenarians has not previously been investigated.…”

Revascularização do miocárdio com emprego de ambas artérias mamárias internas em pacientes com diabetes mellitus

“…Such a benefit seems more evident in young patients, but it cannot be ruled out that those other groups of less favorable prognostic can get advantages of this surgical strategy [9]. DM is long recognized as an important risk factor for infection and dehiscence of surgical wound [10]; therefore, there is a special concern with diabetic patients.…”