Why Are We Weighting? Understanding the Estimates From Propensity Score Weighting and Matching Methods.

Background: Propensity score methods are used in observational studies to compensate for the lack of random allocation by balancing measured baseline characteristics between treated and untreated patients. We sought to explain the treatment effect estimates derived from different propensity score methods.

Methods: We performed a retrospective analysis of long-term mortality after single internal mammary artery versus bilateral internal mammary artery (BIMA) conduit in 47 984 index isolated coronary artery bypass grafting procedures from 1992 to 2014 in the Northern New England Cardiovascular Disease Study Group registry using multivariable Cox regression, 1:1 propensity score matching, inverse probability weighting (IPW) among the treated, and IPW among the overall population treatment estimates.

A multi-center analysis of readmission after cardiac surgery: Experience of The Northern New England Cardiovascular Disease Study Group.

Background: Readmissions after cardiac surgery are common and associated with increased morbidity, mortality and cost of care. Policymakers have targeted coronary artery bypass grafting to achieve value-oriented health care milestones. We explored the causes of readmission following cardiac surgery among a regional consortium of hospitals.

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.

Intensity of Glycemic Control Affects Long-Term Survival After Coronary Artery Bypass Graft Surgery.

Background: A patient's hemoglobin (Hb) A level, regardless of diabetic status, is a measure of glycemic control. Studies have found it is an independent predictor of short-term death in patients undergoing coronary artery bypass grafting (CABG). In this study, we used preoperative HbA to assess whether levels are associated with short-term and long-term survival after CABG.

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.

Coronary Revascularization With Single Versus Bilateral Mammary Arteries: Is It Time to Change?

Background: Arterial conduits are preferred to venous conduits for coronary artery bypass grafting because of longer patency. A single internal mammary artery (SIMA) is used routinely. Bilateral internal mammary arteries (BIMA) are used less frequently.

Should Diabetes Be a Contraindication to Bilateral Internal Mammary Artery Grafting?

Background: This study evaluates the influence of bilateral internal mammary artery (BIMA) versus single internal mammary artery (SIMA) grafting on postoperative morbidity and long-term survival among diabetic patients undergoing coronary artery bypass grafting (CABG).

Methods: A multicenter, retrospective analysis of 47,984 consecutive CABGs performed from 1992 to 2014 at 7 medical centers was conducted. Among the study population, 1,482 CABGs with BIMA were identified, and 1,297 BIMA patients were propensity-matched to 1,297 SIMA patients.

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.

Improving patients' readiness for coronary artery bypass graft surgery.

Background: Preoperative interventions improve outcomes for patients after coronary artery bypass surgery (CABG).

Objective: To reduce mortality for patients undergoing urgent CABG.

Methods: Eight centers implemented preoperative aspirin and statin, preinduction heart rate less than 80/min, hematocrit greater than 30%, blood sugar less than 150 mg/dL (8.

Geographic variability in potentially discretionary red blood cell transfusions after coronary artery bypass graft surgery.

Objective: A number of established regional quality improvement collaboratives have partnered to assess and improve care across their regions under the umbrella of the Cardiac Surgery Quality Improvement (IMPROVE) Network. The first effort of the IMPROVE Network has been to assess regional differences in potentially discretionary transfusions (<3 units red blood cells [RBCs]).

Methods: We examined 11,200 patients undergoing isolated nonemergent coronary artery bypass graft surgery across 56 medical centers in 4 IMPROVE Network regions between January 2008 and June 2012.

Impact of preoperative left ventricular ejection fraction on long-term survival after aortic valve replacement for aortic stenosis.

Background: The survival of patients who undergo aortic valve replacement (AVR) for severe aortic stenosis with reduced preoperative ejection fractions (EFs) is not well described in the literature.

Methods And Results: Patients undergoing AVR for severe aortic stenosis were analyzed using the Northern New England Cardiovascular Disease Study Group surgical registry. Patients were stratified by preoperative EF (≥50%, 40%-49%, and <40%) and concomitant coronary artery bypass grafting.

Variability in surgeons' perioperative practices may influence the incidence of low-output failure after coronary artery bypass grafting surgery.

Background: Postoperative low-output failure (LOF) is an important contributor to morbidity and mortality after coronary artery bypass grafting surgery. We sought to understand which pre- and intra-operative factors contribute to postoperative LOF and to what degree the surgeon may influence rates of LOF.

Methods And Results: We identified 11 838 patients undergoing nonemergent, isolated coronary artery bypass grafting surgery using cardiopulmonary bypass by 32 surgeons at 8 centers in northern New England from 2001 to 2009.

Long-term outcomes of endoscopic vein harvesting after coronary artery bypass grafting.

Background: Use of endoscopic saphenous vein harvesting has developed into a routine surgical approach at many cardiothoracic surgical centers. The association between this technique and long-term morbidity and mortality has recently been called into question. The present report describes the use of open versus endoscopic vein harvesting and risk of mortality and repeat revascularization in northern New England during a time period (2001 to 2004) in which both techniques were being performed.

Piloting the NPF data-driven quality improvement initiative.

Objective: To pilot a data-driven quality care program in National Parkinson Foundation (NPF) Centers of Excellence.

Background: Evidence from comparative effectiveness research (CER) can be used to guide decisions regarding health care and to improve quality and efficiency of care. We propose to develop the infrastructure required to conduct CER across an extensive network of NPF Centers of Excellence.

Outcomes of patients undergoing concomitant aortic and mitral valve surgery in northern new England.

Background: Concomitant aortic (AV) and mitral (MV) valve surgery accounts for 4% of all valve procedures in northern New England. We examined in-hospital and long-term mortality.

Methods And Results: This is a report of a prospective study of 1057 patients undergoing concomitant AV and MV surgery from 1989 to 2007.

Long-term survival of the very elderly undergoing aortic valve surgery.

Background: Increasing numbers of the very elderly are undergoing aortic valve procedures. We describe the short- and long-term survivorship for this cohort.

Methods And Results: We conducted a cohort study of 7584 consecutive patients undergoing open aortic valve surgery without (51.

The association of perioperative red blood cell transfusions and decreased long-term survival after cardiac surgery.

Background: Exposure to red blood cell (RBC) transfusions has been associated with increased mortality after cardiac surgery. We examined long-term survival for cardiac surgical patients who received one or two RBC units during index hospitalization.

Methods: Nine thousand seventy-nine consecutive patients undergoing coronary artery bypass graft, valve, or coronary artery bypass graft/valve surgery at eight centers in northern New England during 2001-2004 were examined after exclusions.

Prediction of survival after coronary revascularization: modeling short-term, mid-term, and long-term survival.

Background: Many clinical prediction rules for short-term mortality after coronary revascularization have been developed, validated, and introduced into routine clinical practice. Few rules exist for predicting long-term survival in the modern era of coronary revascularization. We report on the development and validation of models for predicting long-term survival after coronary artery bypass graft surgery and percutaneous coronary intervention on the basis of recent experience.

Appropriateness of coronary artery bypass graft surgery performed in northern New England.

Objectives: The goal of this study was to assess the concordance between the American College of Cardiology (ACC) and the American Heart Association (AHA) 2004 Guideline Update for Coronary Artery Bypass Graft Surgery and actual clinical practice.

Background: There is substantial geographic variability in the population-based rates of coronary artery bypass graft (CABG) procedures, and in recent years, there have been several public concerns about unnecessary cardiac care. The actual rate of inappropriate cardiac procedures is unknown.

Cardiopulmonary bypass recommendations in adults: the northern New England experience.

Using a regional cardiopulmonary bypass (CPB) registry, we compared the practice of CPB at eight northern New England institutions to recently published recommendations. We examined CPB practice among 3597 adult patients undergoing isolated coronary artery bypass grafting surgery from January 2004 to June 2005. Registry variables were used to compare regional CPB practice to recommendations on topics of neurologic protection (pH management, avoidance of hyperthermia, minimizing return of pericardial suction blood, aortic assessment, arterial line filtration), maintenance of euglycemia, reduction of hemodilution, and attenuation of the inflammatory response.

Long-term survival of the very elderly undergoing coronary artery bypass grafting.

Background: Increasing numbers of the very elderly are undergoing coronary artery bypass graft surgery (CABG). Short-term results have been studied, but few data are available concerning long-term outcomes.

Methods: We conducted a cohort study of 54,397 consecutive patients undergoing primary, isolated CABG surgery between July 1, 1987, and June 30, 2006.

Long-term survival after surgery versus percutaneous intervention in octogenarians with multivessel coronary disease.

Background: There is limited information comparing long-term survival after percutaneous coronary intervention (PCI) versus coronary artery bypass grafting (CABG) in patients aged 80 years and older. We studied the long-term survival of octogenarians with multivessel coronary artery disease undergoing PCI or CABG who might have been candidates for either procedure.

Methods: We identified 1693 patients, aged 80 to 89, with two-vessel disease (57.

Long-term survival of patients with chronic obstructive pulmonary disease undergoing coronary artery bypass surgery.

Background: Chronic obstructive pulmonary disease (COPD) is associated with increased in-hospital mortality in patients undergoing coronary artery bypass surgery (CABG). Long-term survival is less well understood. The present study examined the effect of COPD on survival after CABG.

Intraoperative red blood cell transfusion during coronary artery bypass graft surgery increases the risk of postoperative low-output heart failure.

Background: Hemodilutional anemia during cardiopulmonary bypass (CPB) is associated with increased mortality during coronary artery bypass graft (CABG) surgery. The impact of intraoperative red blood cell (RBC) transfusion to treat anemia during surgery is less understood. We examined the relationship between anemia during CPB, RBC transfusion, and risk of low-output heart failure (LOF).