Bruce Ferguson - Academia.edu (original) (raw)

Papers by Bruce Ferguson

JACC: Clinical Electrophysiology, 2017

OBJECTIVES This study sought to determine whether plasma catecholamines and monoamine oxidase-B (... more OBJECTIVES This study sought to determine whether plasma catecholamines and monoamine oxidase-B (MOA-B) are associated with post-operative atrial fibrillation (POAF) in patients undergoing elective cardiac surgery. BACKGROUND Although intra-and post-operative adrenergic tone has been demonstrated to be an causative factor for POAF, the role and association of pre-operative plasma catecholamines remains unclear. METHODS Prior to administration of anesthesia on the morning of surgery, blood samples were obtained from 324 patients undergoing nonemergent coronary artery bypass graft and/or aortic valve surgery with cardiopulmonary bypass at East Carolina Heart Institute. The concentrations of norepinephrine (NE), dopamine (DA), epinephrine (EPI), and enzyme MAO-B were assessed in platelet-rich plasma. A log-binomial regression model was used to determine the association between quartiles of these variables and POAF. RESULTS Levels of NE (p ¼ 0.0006) and EPI (p ¼ 0.047) in the 4th quartile (Q4 þ NE) were positively associated with POAF, whereas DA (p ¼ 0.0034) levels in the 4th quartile (Q4 þ DA Þ were inversely associated with POAF. Adjusting for age, heart failure (HF), and history of atrial fibrillation, the composite pre-operative (adrenergic) plasma marker (Q4 þ NE V Q4 À DA) was associated with a 4-fold increased occurrence of POAF (adjusted p ¼ 0.0001). No association between plasma MAO-B and POAF was observed. CONCLUSIONS Our results suggest that pre-operative adrenergic tone is an important factor underlying POAF. This information provides evidence that assessment of plasma catecholamines may be a low-cost method that is easy to implement for predicting which patients are likely to develop POAF. More investigation in a multicentric setting is needed to validate our results.

American journal of critical care : an official publication, American Association of Critical-Care Nurses, May 1, 2016

Although many patients with chronic obstructive pulmonary disease (COPD) require a prolonged leng... more Although many patients with chronic obstructive pulmonary disease (COPD) require a prolonged length of stay (PLOS) following coronary artery bypass grafting (CABG), the impact of PLOS on long-term survival has not been examined in this population. To determine the association between PLOS and long-term survival among COPD and non-COPD patients after CABG and to examine consequent policy and practice-based implications. A retrospective cohort study of CABG patients was conducted between 2002 and 2011. Long-term survival was compared in patients with and without COPD and stratified by PLOS. Hazard ratios (HR) and 95% confidence intervals (CI) were computed using a Cox regression model. A total of 203 patients (4.2%) had PLOS after nonemergent CABG (N = 4801). PLOS was an important independent predictor of decreased long-term survival (no COPD, no PLOS: HR = 1.0; COPD, no PLOS: adjusted HR [95% CI], 1.8 [1.5-2.1]; no COPD, PLOS: 3.3 [2.5-4.4]; COPD, PLOS: 6.0 [4.4-8.2]; PTrend < .00...

The American Journal of Cardiology, 2016

Obesity has been identified as a risk factor for postoperative atrial fibrillation (POAF) followi... more Obesity has been identified as a risk factor for postoperative atrial fibrillation (POAF) following coronary artery bypass grafting (CABG). However, no studies have addressed the influence of race on this association. A total of 13,594 patients undergoing first-time, isolated CABG without preoperative atrial fibrillation between 1992 and 2011 were included in our study. The association

International Journal of Environmental Research and Public Health, 2014

Mortality represents an important outcome measure following coronary artery bypass grafting. Shor... more Mortality represents an important outcome measure following coronary artery bypass grafting. Shorter survival times may reflect poor surgical quality and an increased number of costly postoperative complications. Quality control efforts aimed at increasing survival times may be misleading if not properly adjusted for case-mix severity. This paper demonstrates how to construct and cross-validate efficiency-outcome plots for a specified time (e.g., 6-month and 1-year survival) after coronary artery bypass grafting, accounting for baseline cardiovascular risk factors. The application of this approach to regional centers

Journal of Critical Care, 2014

Background-While hemodynamic monitoring is often performed following coronary artery bypass graft... more Background-While hemodynamic monitoring is often performed following coronary artery bypass grafting (CABG), the relationship between postoperative central venous pressure (CVP) measurement and clinical outcomes is unknown. Methods-Detailed clinical data were analyzed from 2,390 randomly selected patients undergoing high risk CABG or CABG/valve at 55 hospitals participating in the Society of Thoracic Surgeons' National Cardiac Surgery Database from 2004 to 2005. Eligible patients underwent elective/urgent isolated CABG with an ejection fraction < 40%, or elective/urgent CABG at age ≥65 years with diabetes or a glomerular filtration rate 60 mL/min per 1.73 m 2. Correlation between post-operative CVP and in-hospital / 30-day mortality and renal failure was assessed as a continuous variable, both unadjusted and after adjusting for important clinical factors using logistic regression modeling. Results-Mean age was 72 years, 54% of patients had diabetes mellitus, 49% were urgent procedures, and mean cardiopulmonary bypass time was 105 minutes. Patients' CVP 6 hours postoperation was strongly associated with in-hospital and 30 day mortality: odds ratio (OR) 1.5 (95% confidence interval [CI] 1.23, 1.87) for every 5 mmHg increase in CVP, p<0.0001. This association remained significant after risk-adjustment for cardiac index: adjusted OR 1.44 (95% CI 1.10, 1.89), p<0.01. A model adjusting for cardiac index also revealed increased incidence of mortality or renal failure: adjusted OR 1.5 (95% CI 1.28, 1.86) for every 5 mmHg increase in CVP, p<0.0001. Conclusion-Patients' central venous pressure at 6 hours following CABG surgery was highly predictive of operative mortality or renal failure, independent of cardiac index and other important

The Heart Surgery Forum, 2014

Background: The effect of race on long-term survival of patients undergoing elective and nonelect... more Background: The effect of race on long-term survival of patients undergoing elective and nonelective coronary artery bypass grafting (CABG) is currently unknown. The purpose of this study was to compare long-term survival between black and white CABG patients by operative status.Methods: Long-term survival of black versus white patients undergoing elective and nonelective CABG procedures between 1992 and 2011 was compared. Survival probabilities were computed using the Kaplan-Meier product-limit method and stratified by race. Hazard ratios (HR) and 95% confidence intervals (CI) were computed using a Cox regression model.Results: A total of 13,774 patients were included in this study. The median follow-up time for study participants was 8.2 years. Black patients undergoing elective CABG died sooner than whites (adjusted HR = 1.4, 95% CI = 1.2�1.5). Survival was similar between blacks and whites in the nonelective population (adjusted HR = 1.0, 95% CI = 0.96�1.1).Conclusions: Black ra...

The Journal of Thoracic and Cardiovascular Surgery, 2006

In some respects, outcome reporting in valvular surgery has been hampered by focusing on specific... more In some respects, outcome reporting in valvular surgery has been hampered by focusing on specific populations, reluctance to publish high-risk subgroups, and possibly skewed or inadequate samples. The goal of this study was to evaluate risk factors for operative mortality comprehensively across the entire spectrum of cardiac valvular procedures over the past decade. Methods: All 409,904 valve procedures in the Society of Thoracic Surgeons database performed between 1994 and 2003 were assessed, and Society of Thoracic Surgeons preoperative and operative variables were related to operative mortality by using a multivariable logistic regression model. Data were greater than 95% complete, and the relative importance of relevant risk factors was determined by ranking odds ratios. The analysis had a high predictive power, with a C statistic of 0.735. Results: In the model, 19 variables independently influenced operative mortality (all P Ͻ .01). The most significant was nonelective (acute) presentation (odds ratios, 2.11), followed by advanced age (odds ratios, 1.88), reoperation (odds ratios, 1.61), endocarditis (odds ratios, 1.59), and coronary disease (odds ratios, 1.58). Generally, valve replacement was associated with higher mortality than repair (odds ratios, 1.52). Overall, female gender was very important (odds ratios, 1.37), and earlier year of operation increased risk (odds ratios, 1.34), implying improving outcomes over time. Although any single comorbidity, on average, was only moderately contributory (odds ratios, 1.19), specific comorbidities, such as renal failure, or multiple comorbidities in a given patient could be very significant. Aortic root reconstruction carried the highest risk (odds ratios, 2.78), followed by tricuspid valve surgery (odds ratios, 2.26), multiple valve procedures (odds ratios, 2.06), and then isolated mitral (odds ratios, 1.47), pulmonic (odds ratios, 1.29), and aortic (reference procedure) operations. Reduced ejection fraction and severity of valve lesion were relatively less important (odds ratios, 1.34 and 0.83, respectively). Conclusions: These data illustrate the significance of acute presentation in determining operative risk, and earlier surgical intervention under elective conditions might be emphasized for all types of significant valve lesions. Because aortic root reconstruction doubles mortality compared with simple aortic valve procedures, root replacement should be reserved for specific root pathology. Finally, issues related to reoperation, endocarditis, valve repair, gender, and the various procedures deserve more detailed examination. S cientific understanding of how baseline patient variables influence operative mortality in cardiac valvular surgery may have been limited by several factors. Most studies have reviewed small series from single centers and have focused on highly specific and usually low-risk subgroups. Complex valvular procedures are not available in sufficient numbers in most hospitals to allow a comprehensive analysis, and because the more complicated cases tend to have

The Journal of Thoracic and Cardiovascular Surgery, 2008

GeneChip technology was used to investigate the gene expression profile in the lungs of a rat mod... more GeneChip technology was used to investigate the gene expression profile in the lungs of a rat model of pulmonary arteriovenous malformations developing after cavopulmonary anastomosis. Significant modulation in expression of a number of genes was found, including several involved in angiogenesis and vascular remodeling.

Journal of the American College of Cardiology, 2004

This study utilizes Markov decision analysis to assess the relative benefits of prophylactic aort... more This study utilizes Markov decision analysis to assess the relative benefits of prophylactic aortic valve replacement (AVR) at the time of coronary artery bypass graft surgery (CABG). Multiple sensitivity analyses were also performed to determine the variables that most profoundly affect outcome. BACKGROUND The decision to perform CABG or concomitant CABG and AVR (CABG/AVR) in asymptomatic patients who need CABG surgery but have mild to moderate aortic stenosis (AS) is not clear-cut. METHODS We performed Markov decision analysis comparing long-term, quality-adjusted life outcomes of patients with mild to moderate AS undergoing CABG versus CABG/AVR. Age-specific morbidity and mortality risks with CABG, CABG/AVR, and AVR after a prior CABG were based on the Society of Thoracic Surgeons national database (n ϭ 1,344,100). Probabilities of progression to symptomatic AS, valve-related morbidity, and age-adjusted mortality rates were obtained from available published reports. RESULTS For average AS progression, the decision to replace the aortic valve at the time of elective CABG should be based on patient age and severity of AS measured by echocardiography. For patients under age 70 years, an AVR for mild AS is preferred if the peak valve gradient is Ͼ25 to 30 mm Hg. For older patients, the threshold increases by 1 to 2 mm Hg/year, so that an 85-year-old patient undergoing CABG should have AVR only if the gradient exceeds 50 mm Hg. The AS progression rate also influences outcomes. With slow progression (Ͻ3 mm Hg/year), CABG is favored for all patients with AS gradients Ͻ50 mm Hg; with rapid progression (Ͼ10 mm Hg/year), CABG/AVR is favored except for patients Ͼ80 years old with a valve gradient Ͻ25 mm Hg. CONCLUSIONS This study provides a decision aid for treating patients with mild to moderate AS requiring CABG surgery. Predictors of AS progression in individual patients need to be better defined.

Journal of the American College of Cardiology, 2008

For coronary artery disease with unprotected left main stem (LMS) stenosis, coronary artery bypas... more For coronary artery disease with unprotected left main stem (LMS) stenosis, coronary artery bypass grafting (CABG) is traditionally regarded as the "standard of care" because of its well-documented and durable survival advantage. There is now an increasing trend to use drug-eluting stents for LMS stenosis rather than CABG despite very little high-quality data to inform clinical practice. We herein: 1) evaluate the current evidence in support of the use of percutaneous revascularization for unprotected LMS; 2) assess the underlying justification for randomized controlled trials of stenting versus surgery for unprotected LMS; and 3) examine the optimum approach to informed consent. We conclude that CABG should indeed remain the preferred revascularization treatment in good surgical candidates with unprotected LMS stenosis.

Journal of the American College of Cardiology, 2003

We sought to examine trends in the use and outcomes of transmyocardial revascularization (TMR) in... more We sought to examine trends in the use and outcomes of transmyocardial revascularization (TMR) in community practice. We also identified important risk factors for TMR and compared outcomes of TMR combined with coronary artery bypass graft surgery (TMR ϩ CABG) versus bypass alone in patients receiving incomplete revascularization. BACKGROUND Although it is approved for use as a stand-alone procedure, there are limited data on the outcomes of (TMR ϩ CABG). METHODS We identified 3,717 patients receiving TMR at 173 U.S. hospitals participating in the Society of Thoracic Surgeons (STS) National Cardiac Database. Baseline characteristics and outcomes in these patients were compared with those from six published randomized TMR trials. Multivariable logistic regression was used to identify clinical risk factors for mortality with TMR. Risk-adjusted mortality was also compared for TMR ϩ CABG relative to CABG only in patients not amenable to complete traditional revascularization. RESULTS Between January 1998 and December 2001, the number of STS hospitals performing TMR and total procedural counts increased markedly, driven predominately by more TMR ϩ CABG cases. Overall mortality rates for TMR-alone and TMR ϩ CABG were 6.4% and 4.2%, respectively. Operative risks were significantly higher in those patients with recent myocardial infarction, unstable angina, and depressed ventricular function. Among patients receiving incomplete revascularization, TMR ϩ CABG was not associated with decreased mortality risk compared with CABG alone, adjusted odds ratio 1.11 (95% confidence interval 0.74 to 1.67). CONCLUSIONS The use of TMR, and in particular, TMR ϩ CABG, is expanding in community practice. Although procedural risks are high, there is room for optimization through improved patient selection and timing of the procedure. Further studies of TMR ϩ CABG are needed given its growing use and unclear benefits.

JAMA, 2003

N 1917 ERNEST CODMAN, MD, A Massachusetts surgeon, described his view of a quality evaluation sys... more N 1917 ERNEST CODMAN, MD, A Massachusetts surgeon, described his view of a quality evaluation system for medicine, in which clinicians assessed outcomes and the processes that led to those outcomes. 1 The modern iteration of Codman's quality system for medicine is continuous quality improvement (CQI). 2,3 Adapted from industrial manufacturing principles in Japan and the United States, 4 CQI in medicine is the repetitive cycle of process and outcomes measurement, design and implementation of interventions to improve the processes of care, and remeasurement to determine the effect on quality of care. Successful CQI programs in medicine have been difficult to achieve, in part due to a lack of appropriate information technology 5 and organizational infrastructure. 6 Randomized trials testing the effectiveness of CQI as an approach to quality improvement in medicine to date have yielded mixed results. A report by Soumerai et al 7 documenting the im

JAMA, 2002

Context ␤-Blockade therapy has recently been shown to convey a survival benefit in preoperative n... more Context ␤-Blockade therapy has recently been shown to convey a survival benefit in preoperative noncardiac vascular surgical settings. The effect of preoperative ␤-blocker therapy on coronary artery bypass graft surgery (CABG) outcomes has not been assessed. Objectives To examine patterns of use of preoperative ␤-blockers in patients undergoing isolated CABG and to determine whether use of ␤-blockers is associated with lower operative mortality and morbidity. Design, Setting, and Patients Observational study using the Society of Thoracic Surgeons National Adult Cardiac Surgery Database (NCD) to assess ␤-blocker use and outcomes among 629877 patients undergoing isolated CABG between 1996 and 1999 at 497 US and Canadian sites. Main Outcome Measure Influence of ␤-blockers on operative mortality, examined using both direct risk adjustment and a matched-pairs analysis based on propensity for preoperative ␤-blocker therapy. Results From 1996 to 1999, overall use of preoperative ␤-blockers increased from 50% to 60% in the NCD (PϽ.001 for time trend). Major predictors of use included recent myocardial infarction; hypertension; worse angina; younger age; better left ventricular systolic function; and absence of congestive heart failure, chronic lung disease, and diabetes. Patients who received ␤-blockers had lower mortality than those who did not (unadjusted 30-day mortality, 2.8% vs 3.4%; odds ratio [OR], 0.80; 95% confidence interval [CI], 0.78-0.82). Preoperative ␤-blocker use remained associated with slightly lower mortality after adjusting for patient risk and center effects using both risk adjustment (OR, 0.94; 95% CI, 0.91-0.97) and treatment propensity matching (OR, 0.97; 95% CI, 0.93-1.00). Procedural complications also tended to be lower among treated patients. This treatment advantage was seen among the majority of patient subgroups, including women; elderly persons; and those with chronic lung disease, diabetes, or moderately depressed ventricular function. Among patients with a left ventricular ejection fraction of less than 30%, however, preoperative ␤-blocker therapy was associated with a trend toward a higher mortality rate (OR, 1.13; 95% CI, 0.96-1.33; P=.23). Conclusions In this large North American observational analysis, preoperative ␤-blocker therapy was associated with a small but consistent survival benefit for patients undergoing CABG, except among patients with a left ventricular ejection fraction of less than 30%. This analysis further suggests that preoperative ␤-blocker therapy may be a useful process measure for CABG quality improvement assessment.

International Journal of Environmental Research and Public Health, 2013

The aim of this study was to examine racial differences in long-term survival among hemodialysis ... more The aim of this study was to examine racial differences in long-term survival among hemodialysis patients after coronary artery bypass grafting (CABG). To our knowledge this has not been previously addressed in the literature. Black and white hemodialysis patients undergoing first-time, isolated CABG procedures between 1992 and 2011 were compared. Survival probabilities were computed using the Kaplan-Meier

Circulation, 2008

is defined in the Oxford Pocket American Dictionary of Current English as "a chance or possibilit... more is defined in the Oxford Pocket American Dictionary of Current English as "a chance or possibility of danger, loss, injury, etc." 1 The evaluation of clinical risk and benefit is a mainstay of all clinical investigation in medicine. More recently, it is slowly becoming a component of everyday clinical care. In this issue of Circulation, Singh et al 2 potentially advance the evaluation of risk in the domain of ischemic heart disease.

Catheterization and Cardiovascular Interventions, 2009

The Annals of Thoracic Surgery, 2012

Background-Coronary revascularization trials often use a composite endpoint of major adverse card... more Background-Coronary revascularization trials often use a composite endpoint of major adverse cardiac and cerebrovascular events (MACCE). The usual practice in analyzing data with a composite endpoint is to assign equal weights to each of the individual MACCE elements. Noninferiority margins are used to offset effects of presumably less important components, but their magnitudes are subject to bias. This study describes the relative importance of MACCE elements from a patient perspective. Methods-A discrete choice experiment was conducted. Survey respondents were presented with a scenario that would make them eligible for the SYNTAX 3-Vessel Disease cohort. Respondents chose among pairs of procedures that differed on the 3-year probability of MACCE, potential for increased longevity, and procedure/recovery time. Conjoint analysis derived relative weights for these attributes. Results-In all, 224 respondents completed the survey. The attributes did not have equal weight. Risk of death was most important (relative weight 0.23), followed by stroke (.18), potential increased longevity and recovery time (each 0.17), MI (0.14) and risk of repeat revascularization (0.11). Applying these weights to the SYNTAX 3-year endpoints resulted in a persistent, but decreased margin of difference in MACCE favoring CABG compared to PCI. When labeled only as "Procedure A" and "B," 87% of respondents chose CABG over PCI. When procedures were labeled as "Coronary Stent" and "Coronary Bypass Surgery," only 73% chose CABG. Procedural preference varied with demographics, gender and familiarity with the procedures.

The Annals of Thoracic Surgery, 2007

Background. Obesity has become a public health crisis. Although prior studies in obese patients u... more Background. Obesity has become a public health crisis. Although prior studies in obese patients undergoing cardiac surgical procedures have shown variable effects on outcomes, data are limited for extremely obese patients (body mass index [BMI] > 45). We undertook this study to evaluate outcomes in this cohort. Methods. A retrospective analysis was performed on 14,571 patients in our database who underwent cardiac operations from 1992 to 2005. Patient demographics, comorbidities, and outcomes were recorded. A univariate analysis between two groups: BMI 21 to 34.9 and BMI 45 or more was performed. Logistic regression models were used to identify independent risk factors for 30-day mortality. Longterm follow-up of the extreme obese group was achieved. Results. We identified 128 extreme obese patients, and 480 patients with a BMI of 21.0 to 34.9 were randomly selected for comparison. Univariate analysis showed significant differences in age, gender, and multiple comorbidi-ties, as well as in cardiopulmonary bypass and cross-clamp times, operative procedure, and transfusion requirements. Extreme obese patients had a higher incidence of infection, acute renal failure, and 30-day mortality. Logistic regression analysis showed BMI, preoperative renal insufficiency, and transfusion status to be independent risk factors for 30-day mortality. Follow-up data did not reveal significant functional improvements. Long-term survival was 33.6% at 12 years. Conclusions. Extreme obese patients undergoing cardiac surgical procedures have higher perioperative morbidity and mortality compared with a lower BMI group. BMI and preoperative renal insufficiency increase mortality in both groups, whereas transfusion does so only in the extreme obese. These patients can realize acceptable outcomes from cardiac procedures, but continue to suffer from the comorbidities of obesity.

The Journal of Thoracic and Cardiovascular Surgery, 2012

Objective: Patients with coronary artery disease complicated by moderate ischemic mitral regurgit... more Objective: Patients with coronary artery disease complicated by moderate ischemic mitral regurgitation have demonstrably poorer outcome than do patients with coronary artery disease but without mitral regurgitation. The optimal treatment of this condition has become increasingly controversial, and a randomized trial evaluating current practices is warranted. Methods: We describe the design and initial execution of the Cardiothoracic Surgical Trials Network Surgical Interventions for Moderate Ischemic Mitral Regurgitation Trial. Results: This is an ongoing prospective, multicenter, randomized, controlled clinical trial designed to test the safety and efficacy of mitral repair in addition to coronary artery bypass grafting in the treatment of moderate ischemic mitral regurgitation. Conclusions: The results of the Cardiothoracic Surgical Trials Network Surgical Interventions for Moderate Ischemic Mitral Regurgitation Trial will provide long-awaited information on controversial therapies for this morbid disease process.