Thoracic Surgery Risk Research Articles

Prospective, Comprehensive Assessment of Cardiac Troponin T Testing After Coronary Artery Bypass Graft Surgery

The significance and clinical role of cardiac troponin testing after coronary artery bypass grafting remain unclear. Cardiac troponin T (cTnT) was measured during the first 24 hours after coronary artery bypass graft surgery in 847 consecutive patients. Only 17 patients (2.0%) had new Q waves or left bundle-branch block after surgery; however, cTnT elevation was observed in nearly all subjects, with a median cTnT concentration of 1.08 ng/mL overall. Direct predictors of postoperative cTnT values included preoperative myocardial infarction (P<0.001), preoperative intraaortic balloon pump (P<0.001), intraoperative/postoperative intraaortic balloon pump (P<0.001), number of distal anastomoses (P=0.005), bypass time (P<0.001), and number of intraoperative defibrillations (P=0.009), whereas glomerular filtration rate (P<0.001), off-pump coronary artery bypass grafting (P=0.003), and use of warm cardioplegia (P=0.02) were inversely associated with cTnT values. A linear association was seen between cTnT levels and length of stay and ventilator hours, and in an analysis adjusted for the Society for Thoracic Surgery Risk Model, cTnT remained independently prognostic for death (odds ratio, 3.20; P=0.003), death or heart failure (odds ratio, 2.04; P=0.008), death or need for vasopressors (odds ratio, 2.70; P<0.001), and the composite of all 3 (odds ratio, 2.57; P<0.001). In contrast to consensus-endorsed cTnT cut points for postoperative evaluation, a cTnT <1.60 ng/mL had a negative predictive value of 93% to 99% for excluding various post-coronary artery bypass graft surgery complications. cTnT concentrations after coronary artery bypass graft surgery are nearly universally elevated, are determined by numerous factors, and are independently prognostic for impending postoperative complications when used at appropriate cut points.

Abstract 2307: Contemporary Perioperative Results of Isolated Aortic Valve Replacement for Aortic Stenosis: Implications for Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (AVI) is compelling for some high-risk patients with aortic stenosis (AS). However, comparison of procedure outcomes with older surgical series may overestimate operative risk. We therefore analyzed our contemporary series of isolated aortic valve replacement (AVR) for AS. From April 2004 to January 2008, 642 patients underwent AVR with or without concomitant cardiac procedures. Of these patients, 175 patients had an isolated AVR, and 140 patients underwent isolated AVR for AS. The characteristics were age 68, male gender 56%, ejection fraction 57%. Sixty-four percent had a minimally-invasive AVR and 18% were reoperations. Twenty percent were 80 years old or greater, 35% were in NYHA functional class III-IV, and 4% had an estimated operative mortality of 10% or greater using the Society of Thoracic Surgery (STS) risk calculator. Thirty-day mortality was 0%, but there was one in-hospital death (0.7%) from complications of an esophageal perforation. Reoperation for bleeding occurred in 5.7%, cerebrovascular accident (CVA) in 0%, acute renal failure (ARF) in 2.9%, myocardial infarction (MI) in 0%. Bioprosthetic valves were used in 98.6% and mechanical in 1.4%. Mean gradient decreased from 48 mmHg to10 mmHg. Actuarial survival was 97% and 90% at 1 and 3 years. Patients &gt;80 years (n=28) were more likely to have an increased length of hospital stay (9.8 versus 6.3 days, p=0.01) and less likely to be discharged to home (48% versus 86%, p&lt;0.01) as compared to patients &lt;80 years. Today, AVR for AS can be performed in many high-risk patients with low operative mortality and morbidity, although patients over 80 years are at greater risk of prolonged recovery. Transcatheter AVI should be compared to this high threshold.

Comparison of Outcomes in High-Risk Patients >70 Years of Age With Aortic Valvuloplasty and Percutaneous Coronary Intervention Versus Aortic Valvuloplasty Alone

The goal of this study was to compare outcomes of combined balloon aortic valvuloplasty (BAV) plus percutaneous coronary intervention (PCI) with BAV alone in a surgically high risk, older (>70 years) population with both aortic stenosis (AS) and coronary artery disease (CAD). The medical records, coronary angiograms, and procedural reports of 100 consecutive patients who underwent BAV and coronary angiography at our institution from July 2003 to November 2006 were reviewed. Seventeen patients (mean age 86.2+/-6.4 years) underwent combined (nonstaged) BAV and PCI with a calculated Society of Thoracic Surgery risk score of 13.5%+/-6.7; 13 of these underwent coronary stenting before BAV and 4 after BAV. All 17 patients were successfully treated with this combined strategy. The incidence of periprocedural mortality, myocardial infarction, and stroke was zero. An additional 25 patients (mean age 85.9+/-6.9) with CAD were identified who underwent BAV alone with a Society of Thoracic Surgery risk score of 12.6+/-5.7%. PCI in these patients was avoided primarily because of greater lesion complexity or a perceived low probability of symptomatic benefit. There was 1 procedural death, no myocardial infarction, and 1 postprocedural stroke in these 25 patients. The procedural duration and hospital length of stay for the combined BAV and PCI group was 98.8+/-17.6 minutes and 4.1+/-2.8 days, respectively, and for the BAV only group was 86.2+/-27.3 minutes and 3.3+/-2.1 days, respectively. In conclusion, with appropriate selection, BAV plus PCI was safely performed in this retrospective series of elderly, high-risk patients with severe AS and CAD.

Feasibility of transcatheter intervention for severe aortic stenosis in patients ≥90 years of age: Aortic valvuloplasty revisited

The goals of this study were to determine the feasibility, safety, and early outcomes of balloon aortic valvuloplasty (BAV) for severe aortic stenosis in a nonagenarian population. This very elderly population is expanding rapidly, has a high incidence of aortic stenosis, and uncommonly undergoes surgical aortic valve replacement. These patients may best be treated with a transcatheter approach due to comorbidities, surgical risk, and personal preference. We reviewed 31 consecutive patients >or=90 years of age who underwent BAV at our institution from July 2003 to August 2006 for data pertinent to patient characteristics, procedural techniques, and 30-day outcomes. Our patients had a mean age of 93 +/- 3.0 years (90-101). The society of thoracic surgery risk score was 18.5 (+/-10.2) and logistic Euroscore was 35.8 (+/-19.3). Twenty-five patients (81%) underwent retrograde BAV and 6 (19%) antegrade BAV. Five patients (16%) underwent combined BAV and coronary stenting. Overall mean aortic valve area increased from 0.52 cm2 (+/-0.17) to 0.92 cm2 (+/-0.22) and mean New York Heart Association (NYHA) functional class improved from 3.4 to 1.8. Intraprocedural mortality occurred in one patient (3.2%) and 30-day mortality in three patients (9.7%). BAV can be carried out in high risk nonagenarian patients with an acceptable complication rate, low perioperative mortality, and early improvement in NYHA functional class.

Prestorage Leukoreduction of Transfused Red Cells Is Associated with Significant Ongoing 2–12 Month Survival Benefit in Cardiac Surgery Patients.

Introduction: Red cell (RBC) transfusion (vs no transfusion) in cardiac surgery is associated with higer operative mortality and shortened long-term survival. Studies have suggested use of leukoreduced RBCs vs standard RBCs in transfused cardiac surgery patients is associated with improved short term (60 day) survival. It is unclear if this benefit persists longer term. Study Aim: This prospective, randomized, double-blind, 3-center trial compared short term and intermediate-term mortality (2–12 mos) in adult cardiac surgery patients undergoing cardiopulmonary bypass (CPB) randomized to receive either prestorage leukoreduced RBCs (LR-RBCs) vs standard RBCs (S-RBCs)Methods: 1226 cardiac surgery patients (undergoing coronary artery bypass grafting, cardiac valve replacement, or a combination of the two) were pre-operatively randomized to receive either LR- or S-RBCs. Patients were operated on by the same group of surgeons. Patients and clinicians were blinded as to product type. All deaths were verified by National Death Index records.Results: 562 patients (45.8%) were transfused: 304 received LR-RBCs and 258 S-RBCs. Groups were statistically equivalent demographically and by all Society of Thoracic Surgery risk criteria. Operative mortality was not affected. However a survival benefit for the LR-RBC group was evident at 60 days which persisted for 12 months (see Table 1). Mortality for non-transfused patients was significantly lower than for patients receiving either LR- or S-RBCs at all time points (p<0.0001).Conclusion: In adult cardiac surgery patients undergoing CPB who require transfusion, use of LR-RBCs vs S-RBCs is associated with significant improvement in survival at 2 months, and this survival advantage persists for up to 1 year.Table 1:Percent (%) Mortality--Operative (Op) and Cumulative by Month (mo) Post-operativeOp2 mo4 mo6 mo*9 mo*12 mo*LD-RBCs4.94.95.35.95.97.0S-RBCs7.09.79.710.111.311.7p-value0.3050.0290.0440.0700.0250.053*Kaplan-Meier (KM) analysis

Port-Access-Assisted Aortic Valve Replacement: A Comparison of Minimally Invasive and Conventional Techniques

A hybrid Port-Access (PA) approach to aortic valve surgery (MPAVR) was designed as a less invasive aortic valve operation. The approach combines components of Port-Access technology with conventional cardiac surgical techniques via a limited sternal incision. This technique is compared to conventional aortic vale replacement (CAVR) for safety and efficacy. One hundred eighty patients had aortic valve surgery between January 1, 2000, and June 30, 2004. Fifty-eight patients (32%) had primary isolated aortic valve replacement, 22 of those 58 patients (38%) underwent MPAVR procedures consisting of a limited inverted-T sternotomy, direct aortic cannulation, a percutaneous PA endocoronary sinus cardioplegia catheter, an endovent pulmonary artery catheter, and a percutaneous femoral endovenous return catheter. Thirty-six patients (62%) had aortic valve replacement by sternotomy and standard cardiopulmonary bypass techniques. The MPAVR and CAVR groups were compared for demographics and intraoperative and postoperative outcomes. Age, obesity, diabetes, New York Heart Association classification, ejection fraction, and other patient characteristics were not significantly different between the groups. MPAVR patients had lower Society of Thoracic Surgery risk scores (3.1 versus 3.9; P = .277). MPAVR patients were more likely to receive a stentless valve (36% versus 11%; P = .042) and required longer operative times (237 min versus 189 min; P <.001). Postoperative complications were minimal and equivalent. A single mortality in the CAVR group resulted in an overall mortality of 1.7%. This hybrid, less invasive PA-assisted approach to aortic valve surgery is safe and effective. A total sternotomy can be avoided in selected aortic valve patients. Results equivalent to CAVR can be expected with this minimal access operation.

Thoracic aortic endografting in patients with high risk for open surgery

Introduction: Out of 154 patients who underwent endografting at our institution between 07/1999 and 09/2005, 124 (80.5%) were at high risk for open thoracic aortic surgery. Our 8-year experience in this subgroup [84 male, 20 female patients; age 62 (16–88) years] is reviewed.