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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 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.

Background How best to define patient-prosthesis mismatch (PPM) continues to be debated. Over time, the indexed effective orifice area has become the most widely used method. However, the clinical relevance of PPM remains controversial. Methods The indexed geometric orifice area and indexed effective orifice area were calculated for 143 patients having undergone aortic valve replacement with a normal left ventricular function 0.45 or less. Using the indexed geometric orifice area method, PPM was defined as nonsignificant if 1.2 cm 2 /m 2 or greater and as significant if less than 1.2 cm 2 /m 2 . Using the indexed effective orifice area method, PPM was considered as nonsignificant if greater than 0.85 cm 2 /m 2 , as moderate if greater than 0.65 cm 2 /m 2 and less than or equal to 0.85 cm 2 /m 2 , and as severe PPM if 0.65 cm 2 /m 2 or less. Results The number of patients classified as having PPM differed according to the method used to predict its presence (PPM: Effective orifice area method=72.7%; geometric method=19.6%). Regardless of the method used to classify PPM there was no significant effect on mortality (adjusted hazard ratio: 2.65 at 1 year, 0.99 at 5 years, 0.92 at 9 years; p = not significant). The postoperative mean transvalvular gradient (17.1 ± 6.5 mm Hg) and left ventricular function (0.50 ± 0.145) improved significantly compared with the preoperative findings. Conclusions The method used to calculate PPM resulted in significant classification discordance. However, regardless of classification, the presence of PPM did not adversely affect long-term outcome.

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 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.

Background Transfusion of red blood cells, while often used for treating blood loss or haemodilution, is also associated with higher infection rates and mortality. The authors implemented an initiative to reduce variation in the number of perioperative transfusions associated with cardiac surgery. Methods The authors examined patients undergoing non-emergent cardiac surgery at a single centre from the third quarter 2004 to the second quarter 2007. Phase I focused on understanding the current process of managing and treating perioperative anaemia. Phase II focused on (1) quality-improvement project dissemination to staff, (2) developing and implementing new protocols, and (3) assessing the effect of subsequent interventions. Data reports were updated monthly and posted in the clinical units. Phase III determined whether reductions in transfusion rates persisted. Results Indications for transfusions were investigated during Phase II. More than half (59%) of intraoperative transfusions were for low haematocrit (Hct), and 31% for predicted low Hct during cardiopulmonary bypass. 43% of postoperative transfusions were for low Hct, with an additional 16% for failure to diurese. The last Hct value prior to transfusion was noted (Hct 25–23, p=0.14), suggestive of a higher tolerance for a lower Hct by staff surgeons. Intraoperative transfusions diminished across phases: 33% in Phase I, 25.8% in Phase II and 23.4% in Phase III (p

Background Cardiothoracic surgical programmes face increasingly more complex procedures performed on evermore challenging patients. Public and private stakeholders are demanding these programmes report process-level and clinical outcomes as a mechanism for enabling quality assurance and informed clinical decision-making. Increasingly these measures are being tied to reimbursement and institutional accreditation. The authors developed a system for linking administrative and clinical registries, in real-time, to track performance in satisfying the needs of the patients and stakeholders, as well as helping to drive continuous quality improvement. Methods A relational surgical database was developed to link prospectively collected clinical data to administrative data sources at Dartmouth-Hitchcock Medical Center. Institutional performance was displayed over time using process control charts, and compared with both internal and regional benchmarks. Results Quarterly reports have been generated and automated for five surgical cohorts. Data are displayed externally on our dedicated website, and internally in the cardiothoracic surgical office suites, operating room theatre and nursing units. Monthly discussions are held with the clinical staff and have resulted in the development of quality-improvement projects. Conclusions The delivery of clinical care in isolation of data and information is no longer prudent or acceptable. The present study suggests that an automated and real-time computer system may provide rich sources of data that may be used to drive improvements in the quality of care. Current and future work will be focused on identifying opportunities to integrate these data into the fabric of the delivery of care to drive process improvement.

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 · min −1 · 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.

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.

Stroke is a devastating complication of coronary artery bypass graft (CABG) surgery. In-hospital outcomes have been described, yet the long-term effect of stroke on mortality following CABG surgery has not been well studied.We examined the survival of 35,733 consecutive patients undergoing isolated CABG surgery in northern New England from 1992 through 2001. Stroke was defined as a new fixed neurologic defect that persisted at least 24 hours after surgery. Patient records were linked to the National Death Index to assess mortality. There were 147,931 person years of follow-up and 5,705 deaths. Cox proportional hazard regression was used to calculate the adjusted hazard ratios (HR) and 95% confidence intervals (95% CI). We identified the 5-year survival stratified by primary stroke mechanism, the patient's functional impact, and discharge location among a subset of patients who had strokes between 1992 and 2000.Perioperative stroke occurred in 575 patients (1.61%). Patients who had strokes had more comorbidities. After adjustments for differences in baseline patient and clinical characteristics, patients who had perioperative stroke were at a significantly increased risk for death (HR, 3.20; 95% CI, 2.80 to 3.66; p0.0001). Survival for patients with stroke at 1, 5, and 10 years was 83.0%, 58.7%, and 26.9%, respectively. Five-year survival decreased among patients who had major functional limitations before discharge, among those who had hypoperfusion strokes, and among patients who were discharged to locations other than home or rehabilitation facilities.Perioperative stroke is associated with a very substantial increased risk of postoperative death among CABG surgery patients. The greatest risk of death was noted within the first year after surgery. Survival after 1 year approximates that of patients who did not suffer a stroke.

Background Predicting risk for aortic and mitral valve surgery is important both for informed consent of patients and objective review of surgical outcomes. Development of reliable prediction rules requires large data sets with appropriate risk factors that are available before surgery. Methods Data from eight Northern New England Medical Centers in the period January 1991 through December 2001 were analyzed on 8,943 heart valve surgery patients aged 30 years and older. There were 5,793 cases of aortic valve replacement and 3,150 cases of mitral valve surgery (repair or replacement). Logistic regression was used to examine the relationship between risk factors and in-hospital mortality. Results In the multivariable analysis, 11 variables in the aortic model (older age, lower body surface area, prior cardiac operation, elevated creatinine, prior stroke, New York Heart Association [NYHA] class IV, congestive heart failure [CHF], atrial fibrillation, acuity, year of surgery, and concomitant coronary artery bypass grafting) and 10 variables in the mitral model (female sex, older age, diabetes, coronary artery disease, prior cerebrovascular accident, elevated creatinine, NYHA class IV, CHF, acuity, and valve replacement) remained independent predictors of the outcome. The mathematical models were highly significant predictors of the outcome, in-hospital mortality, and the results are in general agreement with those of others. The area under the receiver operating characteristic curve for the aortic model was 0.75 (95% confidence interval [CI], 0.72 to 0.77), and for the mitral model, 0.79 (95% CI, 0.76 to 0.81). The goodness-of-fit statistic for the aortic model was χ 2 [8 df] = 11.88, p = 0.157, and for the mitral model it was χ 2 [8 df] = 5.45, p = 0.708. Conclusions We present results and methods for use in day-to-day practice to calculate patient-specific in-hospital mortality after aortic and mitral valve surgery, by the logistic equation for each model or a simple scoring system with a look-up table for mortality rate.

Single-center studies suggest substantial variation in intraaortic balloon pump (IABP) utilization. Our purpose is to examine IABP utilization over time and across medical centers.This was a prospective cohort of 29,961 consecutive patients undergoing isolated coronary artery bypass graft surgery, between 1995 and 2000, at 10 centers (eight in northern New England and two in Canada).A total of 2,678 (8.9%) patients received an IABP. The rate of preoperative IABP insertion was 6.3%, and that of intra- or postoperative insertion was 2.6%. During the 6 years, IABP use increased from 7.0% to 10.3% (p(trend)0.001). Preoperative IABP insertion increased from 5.4% to 7.8% (p(trend)0.001). There was no significant increase in intra-/postoperative IABP insertion 1.7% to 3.4% (p(trend) = 0.34). Adjustment for changes in patient and disease characteristics did not substantially alter these results. The rate of IABP use varied substantially by center, from 5.9% to 16.4% (p0.001). Adjustment for patient and disease characteristics resulted in variation from 4.8% to 12.8% across the 10 centers (p0.001). The adjusted rates of preoperative IABP insertion varied from 3.6% to 13.7% (p0.001), and the rates of intra-/postoperative IABP insertion ranged from 1.0% to 5.2% (p0.001). There was no significant correlation between the rates of preoperative and intra-/postoperative IABP use (r(s) = 0.085, p = 0.815).During the 6 years, there was a 47% increase in the rate of IABP utilization. Even after adjustment, there was almost threefold variation in IABP use across centers. This variation likely reflects lack of consensus on the appropriate use of the IABP in CABG patients.

Background— Renal insufficiency after coronary artery bypass graft (CABG) surgery is associated with increased short-term and long-term mortality. We hypothesized that preoperative patient characteristics could be used to predict the patient-specific risk of developing postoperative renal insufficiency. Methods and Results— Data were prospectively collected on 11 301 patients in northern New England who underwent isolated CABG surgery between 2001 and 2005. Based on National Kidney Foundation definitions, moderate renal insufficiency was defined as a GFR 2 and severe renal insufficiency as a GFR 12 000, prior CABG, congestive heart failure, peripheral vascular disease, diabetes, hypertension, and preoperative intraaortic balloon pump. The predictive model was significant with χ 2 150.8, probability value Conclusions— We developed a robust prediction rule to assist clinicians in identifying patients with normal, or near normal, preoperative renal function who are at high risk of developing severe renal insufficiency. Physicians may be able to take steps to limit this adverse outcome and its associated increase in morbidity and mortality.