Using Biomarkers to Improve the Preoperative Prediction of Death in Coronary Artery Bypass Graft Patients

The current risk prediction models for mortality following coronary artery bypass graft (CABG) surgery have been developed on patient and disease characteristics alone. Improvements to these models potentially may be made through the analysis of biomarkers of unmeasured risk. We hypothesize that preoperative biomarkers reflecting myocardial damage, inflammation, and metabolic dysfunction are associated with an increased risk of mortality following CABG surgery and the use of biomarkers associated with these injuries will improve the Northern New England (NNE) CABG mortality risk prediction model. We prospectively followed 1731 isolated CABG patients with preoperative blood collection at eight medical centers in Northern New England for a nested case-control study from 2003–2007. Preoperative blood samples were drawn at the center and then stored at a central facility. Frozen serum was analyzed at a central laboratory on an Elecsys 2010, at the same time for Cardiac Troponin T, N-Terminal pro-Brain Natriuretic Peptide, high sensitivity C-Reactive Protein, and blood glucose. We compared the strength of the prediction model for mortality using multivariable logistic regression, goodness of fit and tested the equality of the receiving operating characteristic curve (ROC) area. There were 33 cases (dead at discharge) and 66 randomly matched controls (alive at discharge). The ROC for the preoperative mortality model was improved from .83 (95% confidence interval: .74–.92) to .87 (95% confidence interval: .80–.94) with biomarkers (p-value for equality of ROC areas .09). The addition of biomarkers to the NNE preoperative risk prediction model did not significantly improve the prediction of mortality over patient and disease characteristics alone. The added measurement of multiple biomarkers outside of preoperative risk factors may be an unnecessary use of health care resources with little added benefit for predicting in-hospital mortality

Comparative effectiveness of coronary artery bypass grafting versus percutaneous coronary intervention in a real-world Surgical Treatment for Ischemic Heart Failure trial population.

OBJECTIVE: There are no prospective randomized trial data to guide decisions on optimal revascularization strategies for patients with multivessel coronary artery disease and reduced ejection fraction. In this analysis, we describe the comparative effectiveness of coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI) in this patient population. METHODS: A multicenter, retrospective analysis of all CABG (n = 18,292) and PCIs (n = 55,438) performed from 2004 to 2014 among 7 medical centers reporting to the Northern New England Cardiovascular Disease Study Group. After applying inclusion and exclusion criteria from the Surgical Treatment for Ischemic Heart Failure trial, there were 955 CABG and 718 PCI patients with an ejection fraction ≤ 35% and 2- or 3-vessel disease. Inverse probability weighting was used for risk adjustment. The primary end point was all-cause mortality. Secondary end points included rates of 30-day mortality, stroke, acute kidney injury, and incidence of repeat revascularization. RESULTS: The median duration of follow-up was 4.3 years (range, 1.59-6.71 years). CABG was associated with improved long-term survival compared with PCI after risk adjustment (hazard ratio, 0.59; 95% confidence interval, 0.50-0.71; P \u3c .01). Although CABG and PCI had similar 30-day mortality rates (P = .14), CABG was associated with a higher frequency of stroke (P \u3c .001) and acute kidney injury (P \u3c .001), whereas PCI was associated with a higher incidence of repeat revascularization (P \u3c .001). CONCLUSIONS: Among patients with reduced ejection fraction and multivessel disease, CABG was associated with improved long-term survival compared with PCI. CABG should be strongly considered in patients with ischemic cardiomyopathy and multivessel coronary disease

Optimal Timing From Myocardial Infarction to Coronary Artery Bypass Grafting on Hospital Mortality.

BACKGROUND: Whether delaying coronary artery bypass grafting (CABG) after myocardial infarction (MI) is associated with better outcomes or is an unnecessary use of health care resources is unclear. This study investigated the relationship between MI-to-CABG timing on in-hospital death. METHODS: From the Northern New England Cardiovascular Disease Study Group (NNE) Cardiac Surgery Registry we identified 3,060 isolated CABG patients with prior MI from 2008 to 2014. We compared in-hospital death by MI-to-CABG timing of less than 1 day, 1 to 2 days, 3 to 7 days, and 8 to 21 days. We adjusted for patient characteristics using logistic regression. RESULTS: Among patients with prior MI, CABG was performed within 1 day for 99 (3.2%), 1 to 2 days for 369 (12.1%), 3 to 7 days for 1,966 (64.3%), and 8 to 21 days for 626 (20.5%) patients. NNE-predicted mortality was similar for patients operated on within 1 day (1.8%), 1 to 2 days (1.8%), and 3 to 7 days (1.9%), but was higher for 8 to 21 days (2.4%) of MI. Crude in-hospital mortality was higher for those with MI-to-CABG time of less than 1 day (5.1%) compared with 1 to 2 days (1.6%), 3 to 7 days (1.6%), and 8 to 21 days (2.7%, p = 0.044). Adjusted in-hospital mortality remained high for less than 1 day (5.4%; 95% CI, 1.5% to 9.4%), and similar for 1 to 2 days (1.8%; 95% CI, 0.4% to 3.1%), 3 to 7 days (1.7%; 95% CI, 1.1% to 2.3%), and 8 to 21 days (2.3%; 95% CI, 1.2% to 3.3%) between MI and CABG. CONCLUSIONS: Patients operated on 1 to 2 days and 3 to 7 days after MI had a similar mortality rate, suggesting it may be possible to reduce the MI-to-CABG interval for some patients without sacrificing outcomes. Patients operated on within 1 day after MI had a higher mortality rate

Does Use of Bilateral Internal Mammary Artery Grafting Reduce Long-Term Risk of Repeat Coronary Revascularization? A Multicenter Analysis.

BACKGROUND: Although previous studies have demonstrated that patients receiving bilateral internal mammary artery (BIMA) conduits during coronary artery bypass grafting have better long-term survival than those receiving a single internal mammary artery (SIMA), data on risk of repeat revascularization are more limited. In this analysis, we compare the timing, frequency, and type of repeat coronary revascularization among patients receiving BIMA and SIMA. METHODS: We conducted a multicenter, retrospective analysis of 47 984 consecutive coronary artery bypass grafting surgeries performed from 1992 to 2014 among 7 medical centers reporting to a prospectively maintained clinical registry. Among the study population, 1482 coronary artery bypass grafting surgeries with BIMA were identified, and 1297 patients receiving BIMA were propensity-matched to 1297 patients receiving SIMA. The primary end point was freedom from repeat coronary revascularization. RESULTS: The median duration of follow-up was 13.2 (IQR, 7.4-17.7) years. Patients were well matched by age, body mass index, major comorbidities, and cardiac function. There was a higher freedom from repeat revascularization among patients receiving BIMA than among patients receiving SIMA (hazard ratio [HR], 0.78 [95% CI, 0.65-0.94]; CONCLUSIONS: BIMA grafting was associated with a reduced risk of repeat revascularization and an improvement in long-term survival and should be considered more frequently during coronary artery bypass grafting

Tissue versus mechanical aortic valve replacement in younger patients: A multicenter analysis.

OBJECTIVE: The goal of this study was to examine the long-term survival of patients between the ages of 50 and 65 years who underwent tissue versus mechanical aortic valve replacement (AVR) in a multicenter cohort. METHODS: A multicenter, retrospective analysis of all AVR patients (n = 9388) from 1991 to 2015 among 7 medical centers reporting to a prospectively maintained clinical registry was conducted. Inclusion criteria were: patients aged 50 to 65 years who underwent isolated AVR. Baseline comorbidities were balanced using inverse probability weighting for a study cohort of 1449 AVRs: 840 tissue and 609 mechanical. The primary end point of the analysis was all-cause mortality. Secondary end points included in-hospital morbidity, 30-day mortality, length of stay, and risk of reoperation. RESULTS: During the study period, there was a significant shift from mechanical to tissue valves (P \u3c .001). There was no significant difference in major in-hospital morbidity, mortality, or length of hospitalization. Also, there was no significant difference in adjusted 15-year survival between mechanical versus tissue valves (hazard ratio, 0.87; 95% confidence interval [CI], 0.67-1.13; P = .29), although tissue valves were associated with a higher risk of reoperation with a cumulative incidence of 19.1% (95% CI, 14.4%-24.3%) versus 3.0% (95% CI, 1.7%-4.9%) for mechanical valves. The reoperative 30-day mortality rate was 2.4% (n = 2) for the series. CONCLUSIONS: Among patients 50 to 65 years old who underwent AVR, there was no difference in adjusted long-term survival according to prosthesis type, but tissue valves were associated with a higher risk of reoperation

The 30-Year Influence of a Regional Consortium on Quality Improvement in Cardiac Surgery.

BACKGROUND: The Northern New England Cardiovascular Disease Study Group (NNECDSG) was founded in 1987 as a regional consortium to improve cardiovascular quality in Maine, New Hampshire, and Vermont. We sought to assess the longitudinal impact of the NNECDSG on quality and cost of coronary artery bypass grafting (CABG) during the past 30 years. METHODS: Patients undergoing isolated CABG at 5 medical centers from 1987-2017 were retrospectively reviewed (n = 67,942). They were divided into 4 time periods: 1987-1999 (n = 36,885), 2000-2005 (n = 14,606), 2006-2011(n = 8470), and 2012-2017 (n = 7981). The first period was the time the NNECDSG initiated a series of quality improvement initiatives including data feedback, quality improvement training, process mapping, and site visits. RESULTS: Throughout the 4 time intervals, there was a consistent decline in in-hospital mortality, from 3.4% to 1.8% despite an increase in predicted risk of mortality (P \u3c .001), and a significant decline in in-hospital morbidity, including return to the operating room for bleeding, acute kidney injury, mediastinitis, and low output failure (P \u3c .001). Median length of stay decreased from 7 to 5 days (P \u3c .001), which translated into potential savings of $82,722,023. There was a decrease in use of red blood cells from 3.1 units to 2.6 units per patient in the most current time, which translated into potential savings of$1,985,456. CONCLUSIONS: By using collaborative quality improvement initiatives, the NNECDSG has succeeded in significant, sustained improvements in quality and cost for CABG during the past 30 years. These data support the utility of a regional consortium in improving quality

Surgical Atrial Fibrillation Ablation Improves Long-Term Survival: A Multicenter Analysis.

BACKGROUND: The Society of Thoracic Surgeons guidelines recommend surgical ablation (SA) at the time of concomitant mitral operations, aortic valve replacement, coronary artery bypass grafting (CABG), and aortic valve replacement plus CABG for patients in atrial fibrillation (AF). The goal of this analysis was to assess the influence of SA on long-term survival. METHODS: A retrospective analysis of 20,407 consecutive CABG or valve procedures from 2008 to 2015 among seven centers reporting to a prospectively maintained clinical registry was conducted. Patients undergoing operation with documented preoperative AF were included (n = 2,740). Patients receiving SA were compared with patients receiving no SA. The primary end point was all-cause mortality. Secondary end points included in-hospital morbidity and mortality. RESULTS: The frequency of SA was 23.1% (n = 634), and an increase was seen in the rate of SA over the study period (p \u3c 0.001). Concomitant SA was performed in 16.2% of CABG, 30.6% of valve, and 24.3% of valve plus CABG procedures. A substantial improvement was found in unadjusted survival among patients undergoing SA (hazard ratio 0.54, 95% confidence interval: 0.42 to 0.70). Moreover, no differences were found in postoperative complications. SA did have longer bypass times (p \u3c 0.001) but a shorter overall length of stay (p \u3c 0.001). After risk adjustment, SA patients had an improved 5-year survival (hazard ratio 0.69, 95% confidence interval: 0.51 to 0.92), and the effect was observed across all operations. CONCLUSIONS: In a multicenter cohort of patients with AF, concomitant SA resulted in substantially improved long-term survival across patients who underwent CABG, valve, and valve plus CABG. These findings support current guidelines from The Society of Thoracic Surgeons that recommend broader application of concomitant SA