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In coronary artery bypass grafting (CABG), the combined use of left and right internal mammary arteries (LIMA and RIMA) — collectively known as bilateral IMAs (BIMAs) provides a survival advantage over the use of LIMA alone. However, gene expression in RIMA has never been compared to that in LIMA. Here we report a genome-wide transcriptional analysis of BIMA to investigate the expression profiles of these conduits in patients undergoing CABG. As expected, in comparing the BIMAs to the aorta, we found differences in pathways and processes associated with atherosclerosis, inflammation, and cell signaling — pathways which provide biological support for the observation that BIMA grafts deliver long-term benefits to the patients and protect against continued atherosclerosis. These data support the widespread use of BIMAs as the preferred conduits in CABG.

Background Elderly patients with aortic stenosis are under-referred for aortic valve replacement surgery. This study investigated the perioperative factors associated with midterm outcomes in a consecutive series of patients undergoing aortic valve replacement with or without coronary artery bypass graft surgery. Methods From 2006 to 2010, 509 patients having aortic valve replacement or aortic valve replacement with coronary artery bypass were grouped according to age (Results and conclusions 5-year survival among octogenarians was 59.2% with an observed 30-day mortality of 1% for aortic valve replacement and 3% for aortic valve replacement with coronary artery bypass. Kaplan-Meier survival analysis showed that age ≥80 years, New York Heart Association functional class III/IV, and left ventricular ejection fraction

OBJECTIVES More elderly patients (80 years of age) are being referred for aortic valve replacement (AVR) with or without CABG. Current risk stratification models may not accurately predict the preoperative risk in these patients. We sought to determine which perioperative variables were relevant in determining short-term (30-day to in-hospital) outcomes in our intuition's series of consecutive AVR and AVR+CABG surgeries. We constructed a novel variable, patient-prosthesis mismatch (PPM) in the presence of diminished functional status (NYHA) classification, and studied its role as a predictor of mortality risk. METHODS From 2006 to 2010, 509 patients undergoing AVR or AVR+CABG were evaluated. We created four groups based on the age and procedure (AVR80, AVR+CABG80, AVR80 and AVR+CABG80). PPM was defined as a calculated effective orifice area index value of ≤ 0.85, and it was calculated from manufacturer-generated charts. In-hospital and 30-day outcomes were assessed using the Chi-square and logistic regression analyses. RESULTS Overall observed 30-day mortality for all groups was lower (n = 8, 1.6%) than the STS-predicted mortality. Reoperation and PPM+NYHA class III-IV were associated with short-term mortality, but age80 years was not. Octogenarians referred for surgery often had advanced heart failure. CONCLUSIONS Overall, short-term outcomes after AVR with or without CABG were excellent and lower than predicted by the STS model. The low risk of AVR with CABG supports the consideration for earlier surgical referral and intervention for patients with a high likelihood of aortic stenosis progression before the onset of advanced heart failure ensues, regardless of the age. This should help further decrease the already very low mortality observed in these series. Efforts to avoid PPM in the setting of advanced heart failure may improve short-term results in this subset of patients.

The current standard of care is to delay coronary surgery 5-7 days after clopidogrel exposure to prevent bleeding complications. We sought to determine the utility of an objective tool (ie, the VerifyNow assay) to measure platelet inhibition (PI) in patients receiving preoperative clopidogrel prior to off-pump coronary artery bypass grafting surgery (OPCABG).Between June 2007 and July 2009, a total of 482 isolated OPCABG procedures were performed at our institution. In 160 patients, the VerifyNow assay results were used to determine timing of the OPCABG. These patients were compared to the remaining 322 patients. We divided the cohort into 4 subgroups: Group 1 patients (n = 205) were not taking clopidogrel; Group 2 patients (n = 117) were taking clopidogrel, but the test was not performed; Group 3 patients (n = 122) were taking clopidogrel and had a preoperative PI result of ≤20%; and Group 4 patients (n = 38) had ≥21% preoperative PI.Demographic and clinical factors were compared in all groups. The median waiting time for surgery from the last dose of clopidogrel was 6 days for the control groups and 3 days for the groups where the test was performed (P.001). Reoperation for bleeding occurred most often in Group 4 (7.9%; P=.003). Blood utilization was lower in Group 1 (24.4%) than in Groups 2 (34.2%), 3 (40.2%), or 4 (55.3%) (P.001). Major complications and postoperative length of stay were similar in all groups.Utilization of a PI tool in the preoperative assessment of OPCABG patients exposed to clopidogrel can provide valuable information to guide the timing of coronary surgery and may lead to a decrease in reoperation for bleeding and blood usage.

OBJECTIVES: Bilateral internal mammary arteries (BIMA) remains widely underutilized in coronary artery bypass grafting (CABG). Although prior research has demonstrated a long-term benefit of the use of BIMA over left internal mammary artery (LIMA)-only, validation of these results is lacking in a contemporary surgical experience. We compared complications and survival at 17-year follow-up in a large series of consecutive CABG patients from a single institution that underwent BIMA grafting with a propensity-matched group where LIMA only was used. METHODS: Propensity scores representing the estimated probabilities of patients receiving either BIMA or LIMA alone were developed based on 22 observed baseline covariates in a logistic regression model with procedure group as the dependent variable. The nearestneighbour-matching algorithm with Greedy 5-1 Digit Matching was used to produce two patient cohorts of 928 patients each balanced for baseline factors. We compared 30-day morbidity and mortality, as well as long-term survival at 5-year intervals up to 17-year follow-up. RESULTS: In-hospital and 30-day mortality was 0.8% for the BIMA group and 1.1% for the LIMA-saphenous vein grafting (SVG). No significant difference was found in complications, mortality and/or length-of-stay between these two groups. Off-pump was done in 48.9% of BIMA cases and 51.3% of LIMA cases. Regardless of the types of grafts used, on-pump patients were more likely to have postoperative permanent strokes and longer postoperative lengths of stay. Use of the BIMA over LIMA-only had a statistically significant impact conferring a 10% survival advantage at 10-year and 18% at 15-year follow-up. The Kaplan–Meier survival curves comparing off-/on-pump BIMA and off-/on-pump LIMA-SVG patients demonstrated a 22% survival advantage for off-pump BIMA patients when compared with on-pump LIMA-SVG patients at 15-year follow-up. CONCLUSIONS: Perioperative complications do not increase with the use of BIMAs. Long-term survival is optimized with off-pump CABG and BIMA grafting. The low morbidity and mortality rates in this series are likely due to the continuous evolution of technology and the adoption of less invasive options for CABG patients. A more widespread use of BIMAs in CABG patients would continue to improve the overall excellent short- and long-term results of this operation.

Clopidogrel is an oral antiplatelet pro-drug prescribed to 40million patients worldwide who are at risk for thrombotic events or receiving percutaneous coronary intervention (PCI). However about a fifth of patients treated with clopidogrel do not respond adequately to the drug. From a cohort of 105 patients on whom we had functional data on clopidogrel response, we used ultra-high throughput sequencing to assay mutations in CYP2C19 and ABCB1, the two genes genetically linked to respond. Testing for mutations in CYP2C19, as recommended by the FDA, only correctly predicted if a patient would respond to clopidogrel 52.4% of the time. Similarly, testing of the ABCB1 gene only correctly foretold response in 51 (48.6%) patients. These results are clinically relevant and suggest that until additional genetic factors are discovered that predict response more completely, functional assays are more appropriate for clinical use.