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 < .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.

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

BACKGROUND: A patient's hemoglobin (Hb) A1c 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 HbA1c to assess whether levels are associated with short-term and long-term survival after CABG. METHODS: From a regional registry of consecutive cases, we identified 6,415 patients undergoing on-pump isolated CABG from 2008 to 2015 with documented preoperative HbA1c level. We defined four HbA1c groups: less than 5.7% (n = 1,713), 5.7% to 6.4% (n = 2,505), 6.5% to 8.0% (n = 1,377), and more than 8% (n = 820). Relationship to in-hospital outcomes and long-term survival was assessed. Outcome rates and hazard ratios were adjusted for patient and disease risk factors using multivariable logistic regression and Cox models. RESULTS: The study included 3,740 patients (58%) not diagnosed as having diabetes and 2,674 with diabetes. Prediabetes (HbA1c 5.7% to 6.4%) was documented in 52% (n = 1,933) of nondiabetic patients. Higher HbA1c values were associated with younger age, female sex, greater body mass index, more comorbid diseases, lower ejection fraction, more 3-vessel coronary disease, and recent myocardial infarction (p < 0.05 trend for all). After adjustment for patient risk, greater HbA1c values were not associated with higher rates of in-hospital death or morbidity. Long-term survival was significantly worse as HbA1c increased. Risk of death increased by 13% for every unit increase in HbA1c (adjusted hazard ratio, 1.13; 95% confidence interval, 1.07 to 1.19; p < 0.001). CONCLUSIONS: Preadmission glycemic control, as assessed by HbA1c, is predictive of long-term survival, with higher levels associated with poorer prognosis. Whether this risk can be modified by better glycemic control postoperatively remains to be determined.

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 < .01). Although CABG and PCI had similar 30-day mortality rates (P = .14), CABG was associated with a higher frequency of stroke (P < .001) and acute kidney injury (P < .001), whereas PCI was associated with a higher incidence of repeat revascularization (P < .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.

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. Crude and adjusted survival across strata of EF was estimated for patients up to 8 years beyond their index admission. A total of 5277 patients underwent AVR for severe aortic stenosis between 1992 and 2008. There were 727 (14%) patients with preoperative EF <40%. Preoperative EF had minimal effect on postoperative morbidity. There was no difference in 30-day mortality across EF strata among the isolated AVR cohort. Preserved EF conferred 30-day survival benefit among the AVR+coronary artery bypass grafting population (EF≥50%, 96%; EF<40%, 91%; P=0.003). Patients with preserved EF had significantly improved 6-month and 8-year survival compared with their reduced EF counterparts. CONCLUSIONS: Survival after AVR or AVR+coronary artery bypass grafting was most favorable among patients with preoperative preserved EF. However, patients with mild to moderately depressed EF experienced a substantial survival benefit compared with the natural history of medically treated patients. Furthermore, minor reductions of EF carried equivalent increased risk to those with more compromised function suggesting patients are best served when an AVR is performed before even minor reductions in myocardial function.

Limited blood transfusion does not impact survival in octogenarians undergoing cardiac operations.

BACKGROUND: We previously reported that transfusion of 1 to 2 units of red blood cells (RBCs) confers a 16% increased hazard of late death after cardiac surgical treatment. We explored whether a similar effect existed among octogenarians. METHODS: We enrolled 17,026 consecutive adult patients undergoing cardiac operations from 2001 to 2008 in northern New England. Patients receiving more than 2 units of RBCs or undergoing emergency operations were excluded. Early (to 6 months) and late (to 3 years, among those surviving longer than 6 months) survival was confirmed using the Social Security Death Index. We estimated the relationship between RBCs and survival, and any interaction by age (<80 years versus ≥80 years) or procedure. We calculated the adjusted hazard ratio (HR), and plotted adjusted survival curves. RESULTS: Patients receiving RBCs had more comorbidities irrespective of age. Patients 80 years of age or older underwent transfusion more often than patients younger than 80 years (51% versus 30%; p<0.001). There was no evidence of an interaction by age or procedure (p>0.05). Among patients younger than 80 years, RBCs significantly increased a patient's risk of early death [HR, 2.03; 95% confidence interval [CI], 1.47, 2.80] but not late death 1.21 (95%CI, 0.88, 1.67). RBCs did not increase the risk of early [HR, 1.47; 95% CI, 0.84, 2.56] or late (HR, 0.92 95% CI, 0.50, 1.69) death in patients 80 years or older. CONCLUSIONS: Octogenarians receive RBCs more often than do younger patients. Although transfusion of 1 to 2 units of RBCs increases the risk of early death in patients younger than 80 years, this effect was not present among octogenarians. There was no significant effect of RBCs in late death in either age group.

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. Our cohort included patients with preoperative ejection fractions >40%. Patients with preoperative intraaortic balloon pumps were excluded. LOF was defined as the need for ≥2 inotropes at 48 hours, an intra- or post-operative intraaortic balloon pumps, or return to cardiopulmonary bypass (for hemodynamic reasons). Case volume varied across the 32 surgeons (limits, 80-766; median, 344). The overall rate of LOF was 4.3% (return to cardiopulmonary bypass, 2.6%; intraaortic balloon pumps, 1.0%; inotrope usage, 0.8%; combination, 1.0%). The predicted risk of LOF did not differ across surgeons, P=0.79, and the observed rates varied from 1.1% to 10.2%, P<0.001. Patients operated by low-rate surgeons had shorter clamp and bypass times, antegrade cardioplegia, longer maximum intervals between cardioplegia doses, lower cardioplegia volume per anastomosis or minute of ischemic time, and less hot-shot use. Patients operated on by higher LOF surgeons had higher rates of postoperative acute kidney injury. CONCLUSIONS: Rates of LOF significantly varied across surgeons and could not be explained solely by patient case mix, suggesting that variability in perioperative practices influences risk of LOF.

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. METHODS AND RESULTS: From 2001 to 2004, 8542 patients underwent isolated coronary artery bypass grafting procedures, 52.5% with endoscopic vein harvesting. Surgical discretion dictated the vein harvest approach. The main outcomes were death and repeat revascularization (percutaneous coronary intervention or coronary artery bypass grafting) within 4 years of the index admission. The use of endoscopic vein harvesting increased from 34% in 2001 to 75% in 2004. In general, patients undergoing endoscopic vein harvesting had greater disease burden. Endoscopic vein harvesting was associated with an increased adjusted risk of bleeding requiring a return to the operating room (2.4 versus 1.7; P=0.03) but a decreased risk of leg wound infections (0.2 versus 1.1; P<0.001). Use of endoscopic vein harvesting was associated with a significant reduction in long-term mortality (adjusted hazard ratio, 0.74; 95% confidence interval, 0.60 to 0.92) but a nonsignificant increased risk of repeat revascularization (adjusted hazard ratio, 1.29; 95% confidence interval, 0.96 to 1.74). Similar results were obtained in propensity-stratified analysis. CONCLUSIONS: During 2001 to 2004 in northern New England, the use of endoscopic vein harvesting was not associated with harm. There was a nonsignificant increase in repeat revascularization, and survival was not decreased.

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 (51.1%; AVR) or with (48.9%; AVR + CABG) concomitant coronary artery bypass graft surgery between November 10, 1987 through June 30, 2006. Patient records were linked to the Social Security Administration's Death Master File. Survivorship was stratified by age and concomitant CABG surgery. During 39 835 person-years of follow-up, there were 2877 deaths. Among AVR, there were 3304 patients <80 years of age, 419 patients 80 to 84 years, and 156 patients > or =85 years (24 patients >90 years). Among AVR+CABG patients, there were 2890 patients <80 years of age, 577 patients 80 to 84 years, and 238 patients > or =85 years (22 patients >90 years). Median survivorship for patients undergoing isolated AVR was 11.5 years (<80 years), 6.8 years (80 to 84 years), 6.2 years (> or =85 years); for patients undergoing AVR+CABG, median survivorship was 9.4 years (<80 years), 6.8 years (80 to 84 years), and 7.1 years (> or =85 years). Among both procedures, adjusted survivorship was significantly different across strata of age (P<0.001). These findings are similar to life expectancy of the general population from actuarial tables: 80 to 84 years (7 years) and > or =85 years (5 years). CONCLUSIONS: Survivorship among octogenarians is favorable, with more than half the patients surviving more than 6 years after their surgery. Concomitant CABG surgery does not diminish median survivorship among patients >80 years of age.

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. The Social Security Administration Death Master File was used to assess long-term survival. Kaplan-Meier and log-rank tests were performed. In-hospital mortality was 15.5% (11.0% for patients <70 years, 18.0% for 70- to 79-year-olds, and 24% for those > or =80 years). Overall median survival was 7.3 years. Median survival without coronary artery bypass grafting was 9.5 years and with coronary artery bypass grafting was 5.7 years (P<0.001). Survival in women was worse than in men (7.3 versus 9.3, years, P=0.033). Median survival by age was 11.0 years for patients <70 years, 5.4 years for 70- to 79-year-olds, and 4.8 years for those > or =80 years. Median survival was not significantly different for patients > or =80 years compared with those who were 70 to 79 years old (P=0.245). CONCLUSIONS: Double-valve surgery has a high in-hospital mortality rate and a median survival of 7.3 years. After patients have survived surgery, long-term survival is similar between men and women, smaller and larger patients, and those receiving MV repair or replacement. Survival continues to decline after surviving surgery for patients > or =70 years old and those who undergo concomitant coronary artery bypass grafting. In patients <70 years, either mechanical valves in both positions or a tissue AV and mitral repair have the lowest in-hospital mortality and the best long-term survival. In patients > or =70 years, tissue valves in both positions have the best in-hospital and long-term survival.

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. A probabilistic match between the regional registry and the Social Security Administration's Death Master File determined mortality through June 30, 2006. Cox Proportional Hazard and propensity methods were used to calculate adjusted hazard ratios. RESULTS: Thirty-six percent of patients (n = 3254) were exposed to one or two RBC units. Forty-three percent of RBCs were given intraoperatively, 56% in the postoperative period and 1% were preoperative. Patients transfused were more likely to be anemic, older, smaller, female and with more comorbid illness. Survival was significantly decreased for all patients exposed to 1 or 2 U of RBCs during hospitalization for cardiac surgery compared with those who received none (P < 0.001). After adjustment for patient and disease characteristics, patients exposed to 1 or 2 U of RBCs had a 16% higher long-term mortality risk (adjusted hazard ratios = 1.16, 95% CI: 1.01-1.34, P = 0.035). CONCLUSIONS: Exposure to 1 or 2 U of RBCs was associated with a 16% increased hazard of decreased survival after cardiac surgery.

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. METHODS: We evaluated 4,684 consecutive isolated coronary artery bypass graft procedures performed in 2004 and 2005 in northern New England. Our regional registry data were used to categorize patients into clinical subgroups. Detailed clinical criteria were then used to categorize procedures within these subgroups as class I (useful and effective), class IIa (evidence favors usefulness), class IIb (evidence less well established), and class III (not useful or effective). RESULTS: Among these 4,684 procedures, we were able to classify 99.6% (n = 4,665). The majority of procedures were class I (87.7%). Class II procedures totaled 10.9%. The remaining 1.4% of procedures were class III. CONCLUSIONS: In this regional study, we found that 98.6% of CABG procedures that could be classified were considered to be appropriate. In these data, actual clinical practice closely follows the recommendations of the 2004 ACC/AHA guidelines for CABG surgery.

Long-term survival and cardiac troponin T elevation in on- and off-pump coronary artery bypass surgery.

INTRODUCTION: The long-term clinical usefulness of conventional coronary artery bypass graft surgery (CCAB) versus off-pump surgery (OPCAB) remains controversial. Long-term survival and elevation in cardiac troponin T (cTnT) concentration following CCAB and OPCAB have not been assessed. We tested the hypothesis that long-term survival rates for CCAB and OPCAB patients were similar when stratified by cTnT concentration. METHODS AND RESULTS: In this prospective cohort, we followed 1511 nonemergency patients with 2- or 3-vessel disease (778 CCAB and 733 OPCAB cases) from a hospital in northern New England to determine if 6-year survival rates for CCAB and OPCAB patients were similar. The patients underwent surgery between 2000 and 2004 by surgeons who used both procedures. Postoperative cTnT elevation was defined as > or =1 ng/mL, the upper quartile of cTnT values. Data were linked to the Social Security Administration Death Master File. Kaplan-Meier analysis and Cox proportional hazards models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI), with adjustments for baseline patient and disease characteristics. Patients were followed for a median of 4.1 years (mean, 4.0 years). Patients were similar with regard to baseline disease characteristics, comorbidities, cardiac history, function, and anatomy. OPCAB was associated with increased rates of postoperative bleeding and with a worse 6-year survival rate compared with CCAB, regardless of cTnT concentration (cTnT <1 ng/mL, P < .013; cTnT > or =1 ng/mL, P = .017). Compared with CCAB patients, the adjusted HR (95% CI) was 1.59 (1.09-2.32) for OPCAB patients with cTnT concentrations <1 ng/mL and 1.93 (1.12-3.31) for OPCAB patients with cTnT concentrations > or =1 ng/mL. CONCLUSION: Survival is better for CCAB patients than for OPCAB patients, regardless of cTnT concentration. This effect is sustained after multivariable adjustment for baseline mortality risk factors.

Long-term survival after cardiac surgery is predicted by estimated glomerular filtration rate.

BACKGROUND: Estimated glomerular filtration rate (eGFR) before coronary artery bypass graft (CABG) surgery is a key risk factor of in-hospital mortality. However, in patients with normal renal function before CABG, acute kidney injury develops after the procedure, making postoperative renal function assessment necessary for evaluation. Postoperative eGFR and its association with long-term survival have not been well studied. METHODS: We studied 13,593 consecutive CABG patients in northern New England from 2001 to 2006. Patients with preoperative dialysis were excluded. Data were linked to the Social Security Association Death Master File to assess long-term survival. Kaplan-Meier and log-rank techniques were used. Patients were stratified by established categories of postoperative eGFR (90 or greater, 60 to 89, 30 to 59, 15 to 29, and less than 15 mL x min(-1) x 1.73 m(-2)). RESULTS: Median follow-up was 2.8 years (mean, 2.7; range, 0 to 5.5). Patients with moderate to severe acute kidney injury (less than 60) after CABG had significantly worse survival than patients with little or no acute kidney injury (90 or greater). CONCLUSIONS: Patients having moderate to severe acute kidney injury after CABG surgery had worse 5-year survival compared with patients who had normal or near-normal renal function.

Neurocognitive outcomes of off-pump versus on-pump coronary artery bypass: a prospective randomized controlled trial.

BACKGROUND: Preliminary reports have documented the safety of off-pump coronary artery bypass graft compared with conventional coronary artery bypass graft surgery. Whereas off-pump coronary artery bypass graft surgery may be associated with improvement in some short-term outcomes, longer-term outcomes and influence on neurocognitive function have not been fully assessed. We examined short-term and intermediate-term neurocognitive and index admission morbidity and mortality after coronary artery bypass surgery performed with and without the use of extracorporeal circulation. METHODS: We prospectively randomly assigned 201 patients undergoing nonemergent isolated coronary artery bypass graft surgery to conventional coronary artery bypass graft surgery (n = 102) or off-pump coronary artery bypass graft surgery (n = 99). The primary end points of the study were neurocognitive function assessed using a 19-test neurocognitive battery at baseline, discharge, and 6 months. Neurocognitive deficit was defined as a 20% or greater reduction from baseline in at least 20% of the tests. Secondary end points included index admission mortality, stroke, low-output cardiac failure, return to the operating room for bleeding, and postoperative troponin release. Risk ratios and 95% confidence intervals were calculated based on intention-to-treat analysis. RESULTS: There was no difference in neurocognitive deficit at discharge (discharge versus preoperative: risk ratio, 0.83; 95% confidence interval, 0.65 to 1.07) or at 6 months (6 months versus preoperative: risk ratio, 0.94; 95% confidence interval, 0.70 to 1.28). There was no significant difference in mortality or morbidity between the two groups. The off-pump coronary artery bypass graft group had fewer patients with troponin release than the conventional coronary artery bypass graft group. CONCLUSIONS: Off-pump coronary artery bypass graft surgery did not result in decreased frequency of neurocognitive deficit. Off-pump coronary artery bypass graft surgery was associated with substantially lower levels of troponin release after surgery.

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 (57.6%) or three-vessel disease (42.4%), without left main disease, undergoing a first, nonemergency revascularization from 1992 to 2001. Adjusted hazard ratios (HR) were calculated for CABG versus PCI. Because survival curves for these procedures crossed midway through year 1, results were analyzed separately for the first 6 months and 6 months to 8 years. RESULTS: PCI was performed in 54.6% of patients with two-vessel disease and 23.7% of those with three-vessel disease. More CABG patients were men (54.7% versus 43.3%). The CABG patients had more peripheral vascular disease (23.1% versus 15.2%) and congestive heart failure (24.5% versus 13.1%) but less renal failure (4.6% versus 9.1%) and fewer prior myocardial infarctions (48.7% versus 53.6%). In-hospital mortality was 3.0% for PCI and 5.9% for CABG (p = 0.005). CABG was associated with poorer survival than PCI during the first 6 months (HR, 1.32; p = 0.135). Survival from 6 months to 8 years was significantly better with CABG for the group as a whole (HR, 0.72; p = 0.005) and for patients with two-vessel disease (HR, 0.68; p = 0.016), and there was a nonsignificant trend for those with three-vessel disease (HR, 0.75; p = 0.177). CONCLUSIONS: Patients aged 80 years or older with multivessel disease must consider the trade-off between the increased early risks of CABG in return for improved long-term survival.

Cardiac troponin T levels in on- and off-pump coronary artery bypass surgery.

BACKGROUND: Conventional coronary artery bypass graft surgery (CCAB) has been associated with greater myocardial injury than off-pump surgery (OPCAB). However, the extent of myocardial injury following CCAB and OPCAB has not been assessed by priority of surgery or the number of diseased vessels. We tested the hypothesis that the additional myocardial injury associated with CCAB compared with OPCAB is sustained when patients are stratified by priority and 2- or 3-vessel disease. METHODS AND RESULTS: In this prospective cohort, we measured 24-hour postoperative cardiac troponin T (cTnT) following CCAB and OPCAB surgery to determine if OPCAB results in less perioperative myocardial damage by priority (urgent or elective). We studied 1511 patients who underwent heart surgery in one hospital in northern New England between 2000 and 2004. Surgeons used either CCAB (778 patients) of OPCAB (733 patients). Unpaired t tests were used to test the mean difference in cTnT between CCAB and OPCAB subgroups. Mean cTnT levels were significantly higher in the CCAB group (0.94 ng/mL) than the OPCAB group (0.18 ng/mL) with P < .001; this difference was consistent across urgent and elective surgeries, and patients with both 2- and 3-vessel disease. CCAB patients consistently demonstrated higher cTnT levels. Similar results were evident when stratified by patient characteristics and surgeon. CONCLUSIONS: In summary, higher postoperative cTnT levels are associated with CCAB than with OPCAB, regardless of priority, number of diseased vessels, patient characteristics, or surgeon. OPCAB results in less myocardial injury in patients, whether they present with 2- or 3-vessel disease and whether they undergo urgent or elective cardiac surgery.

Perioperative increases in serum creatinine are predictive of increased 90-day mortality after coronary artery bypass graft surgery.

BACKGROUND: Impaired renal function after coronary artery bypass graft (CABG) surgery is a key risk factor for in-hospital mortality. However, perioperative increases in serum creatinine and the association with mortality has not been well-studied. We assessed the hypothesis that perioperative increases in creatinine are associated with increased 90-day mortality. METHODS AND RESULTS: We studied 1391 patients in northern New England undergoing CABG in 2001 and evaluated preoperative and postoperative creatinine. Patients with preoperative dialysis were excluded. Data were linked to the National Death Index to assess 90-day survival. Kaplan-Meier and log-rank techniques were used. Patients were stratified by percent increase in creatinine from baseline: <25%, 25% to 49%, 50% to 99%, > or =100%. We assessed 90-day survival and calculated adjusted hazard ratios (HR) and 95% confidence intervals (95% CI) for creatinine groups, adjusting for age and sex. Patients with the largest creatinine increases (50% to 99% or > or =100%) had significantly higher 90-day mortality compared with patients with a smaller increase (<50%; P<0.001). Adjusted HR and 95% CI confirmed patients in the higher 2 groups had an increased risk of mortality compared with the <25% (referent); however, the 25% to 49% group was not different from the referent: 1.80 (95% CI: 0.73 to 4.44), 6.57 (95% CI, 3.03 to 14.27), and 22.10 (95% CI, 11.25 to 43.39). CONCLUSIONS: Patients with large creatinine increases (> or = 50%) after CABG surgery have a higher 90-day mortality compared with patients with small increases. Efforts to identify patients with impaired renal function and to preserve renal function before cardiac surgery may yield benefits for patients in the future.

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. METHODS AND RESULTS: We conducted a prospective study of 33,137 consecutive isolated CABG patients between 1992 and 2001 in northern New England. Records were linked to the National Death Index for long-term mortality data. Cox proportional hazards regression was used to calculate hazard ratios (HRs). Patients were stratified by: no comorbidities (none), COPD, COPD plus comorbidities, and other comorbidities with no COPD. There were 131,434 person years of follow-up and 5344 deaths. The overall incidence rate (deaths per 100 person years) was 4.1. By group, rates were: 2.1 (none), 4.0 (COPD alone), 5.5 (other), and 9.4 (COPD plus; log rank P<0.001). After adjustment, survival with COPD alone was worse compared with none (HR, 1.8; 95% CI, 1.6 to 2.1; P<0.001). Patients with other comorbidities compared with none had even worse survival (HR, 2.2; 95% CI, 2.1 to 2.4; P<0.001). Patients with COPD plus other comorbidities compared with none had the worst long-term survival (HR, 3.6; 95% CI, 3.3 to 3.9; P<0.001). CONCLUSIONS: Patients with only COPD had significantly reduced long-term survival compared with patient with no comorbidities. Patients with COPD and > or = 1 other comorbidity had the worst survival rate when compared with all of the other groups.

Comparison of three measurements of cardiac surgery mortality for the Northern New England Cardiovascular Disease Study Group.

BACKGROUND: There is no consensus on the optimal period during which to assess death after coronary artery bypass graft (CABG) surgery. Three measures are commonly used: in-hospital, 30-day, and procedural (either in-hospital or 30-day) mortality. We used a regional database to calculate the CABG mortality rate using each of these mortality measures. METHODS: Data were collected prospectively on 31,592 consecutive isolated CABG surgeries in northern New England between January 1992 and December 2001. These data were linked to the National Death Index to obtain vital status through December 2001, and used to calculate 30-day and procedural mortality rates. Procedural mortality was defined as death occurring either within the hospital setting or within 30 days of the index procedure. Regional registry data were used to calculate in-hospital mortality rates. RESULTS: Mortality rates and their 95% confidence intervals were calculated. In all but one medical center, the in-hospital mortality was the lowest rate, while in all centers the procedural mortality rate was the highest. There were 1,082 deaths captured by the procedural mortality measure. Of these, 927 were included in the in-hospital mortality measure; 956 occurred within 30 days of surgery. CONCLUSIONS: Each of the measures studied has its advantages and may be used to assess the mortality outcomes of cardiac surgery. The more important issue other than the specific measure used is our ability to measure and validate it conveniently and accurately in actual practice.

Effect of diabetes and associated conditions on long-term survival after coronary artery bypass graft surgery.

BACKGROUND: The effects of diabetes on short-term results of coronary artery bypass graft (CABG) surgery are known, but less is known about the long-term effects of diabetes and diabetic-related sequelae for patients undergoing this surgery. We studied the 10-year survival of nondiabetic and diabetic patients undergoing CABG surgery. METHODS AND RESULTS: A prospective regional cohort study was conducted of 36,641 consecutive isolated CABG patients in northern New England from 1992 through 2001. Patient records were linked to the National Death Index to assess mortality. There were 154,140 person-years of follow-up and 5779 deaths. Kaplan-Meier techniques were used. Survival was stratified into three categories: no diabetes, diabetes without peripheral vascular disease and renal failure, and diabetes with peripheral vascular disease and/or renal failure. The overall annual incidence rate of death was 3.7 deaths per 100 person-years. Annual incidence rates for nondiabetic subjects and diabetic subjects were similar: 3.1 deaths per 100 person-years and 4.4 deaths per 100 person-years, respectively. The annual incidence rate for diabetic subjects with renal failure, peripheral vascular disease, or both was 9.4 deaths per 100 person-years. The log-rank test showed that the survival curves were significantly different (P<0.001). CONCLUSIONS: Patients that have diabetes without the sequelae of renal failure and/or peripheral vascular disease have long-term survival similar to but slightly less than patients without diabetes who undergo CABG surgery. Survival of CABG surgery patients with diabetes is greatly affected by associated comorbidities of peripheral vascular disease and renal failure. This knowledge may help guide the patient as well as the cardiologist and cardiac surgeon in making appropriate decisions in these critically ill patients.