Off-pump or on-pump coronary-artery bypass grafting at 30 days

BACKGROUND

The relative benefits and risks of performing coronary-artery bypass grafting (CABG) with a beating-heart technique (off-pump CABG), as compared with cardiopulmonary bypass (on-pump CABG), are not clearly established.

METHODS

At 79 centers in 19 countries, we randomly assigned 4752 patients in whom CABG was planned to undergo the procedure off-pump or on-pump. The first coprimary outcome was a composite of death, nonfatal stroke, nonfatal myocardial infarction, or new renal failure requiring dialysis at 30 days after randomization.

RESULTS

There was no significant difference in the rate of the primary composite outcome between off-pump and on-pump CABG (9.8% vs. 10.3%; hazard ratio for the off-pump group, 0.95; 95% confidence interval [CI], 0.79 to 1.14; P=0.59) or in any of its individual components. The use of off-pump CABG, as compared with on-pump CABG, significantly reduced the rates of blood-product transfusion (50.7% vs. 63.3%; relative risk, 0.80; 95% CI, 0.75 to 0.85; P<0.001), reoperation for perioperative bleeding (1.4% vs. 2.4%; relative risk, 0.61; 95% CI, 0.40 to 0.93; P=0.02), acute kidney injury (28.0% vs. 32.1%; relative risk, 0.87; 95% CI, 0.80 to 0.96; P=0.01), and respiratory complications (5.9% vs. 7.5%; relative risk, 0.79; 95% CI, 0.63 to 0.98; P=0.03) but increased the rate of early repeat revascularizations (0.7% vs. 0.2%; hazard ratio, 4.01; 95% CI, 1.34 to 12.0; P=0.01).

CONCLUSIONS

There was no significant difference between off-pump and on-pump CABG with respect to the 30-day rate of death, myocardial infarction, stroke, or renal failure requiring dialysis. The use of off-pump CABG resulted in reduced rates of transfusion, reoperation for perioperative bleeding, respiratory complications, and acute kidney injury but also resulted in an increased risk of early revascularization. (Funded by the Canadian Institutes of Health Research; CORONARY ClinicalTrials.gov number, NCT00463294.).

Continuous hydromorphone for pain and sedation in mechanically ventilated infants and children

OBJECTIVE

To describe dosing regimens and efficacy of continuous infusion hydromorphone in mechanically ventilated children.

DESIGN

Retrospective review.

SETTING

Tertiary care, pediatric hospital.

PATIENTS

Ninety-two critically ill children (<18 years old).

MAIN OUTCOME MEASURE(S)

Hydromorphone dosing requirements, concomitant pain and sedation therapy, patient-specific pain scores (using Face Legs Activity Cry Consolability [FLACC] pain scale), and possible adverse drug events related to therapy.

RESULTS

Starting dose was 0.024 +/- 0.04 mg/kg/h. Maximum dose was 0.05 + 0.1 mg/kg/h. Duration of therapy was 182 +/- 169 hours. Most patients received additional pain and sedation therapy. Most mean daily FLACC scores (66 percent) were below 1. Less than 10 percent of scores were above 3; only 1 score was above 6. Mean FLACC score, when averaged per patient course, was 1.004 +/- 0.71. Extracorporeal membrane oxygenation (ECMO) patients had a significantly higher initial and maximum dosing requirement than non-ECMO patients (p = 0.001).

CONCLUSIONS

Continuous infusion hydromorphone appears to be an effective adjunctive analgesic in mechanically ventilated children.

Piloting a novel algorithm for glucose control in the coronary care unit: the RECREATE (REsearching Coronary REduction by Appropriately Targeting Euglycemia) trial

OBJECTIVE

Elevated glucose levels are common after an acute myocardial infarction (AMI) and increase the risk of death. Prior trials of glucose control after AMI have been inconsistent in their ability to lower glucose levels and have reported mixed effects on mortality. We developed a paper-based glucose-lowering algorithm and assessed its feasibility and safety in the setting of AMI.

RESEARCH DESIGN AND METHODS

A total of 287 participants with an acute ST segment elevation myocardial infarction (STEMI) and a capillary glucose level ≥8.0 mmol/L were randomly allocated to glucose management with intravenous glulisine insulin using this algorithm in the coronary care unit (CCU), followed by once-daily subcutaneous insulin glargine for 30 days versus standard glycemic approaches. The primary outcome was a difference in mean glucose levels at 24 h. Participants were followed for clinical outcomes through 90 days.

RESULTS

At 24 h, the mean glucose level was 1.41 mmol/L (95% CI 0.69-2.13) lower in the insulin (6.53 vs. 7.94 mmol/L). Differences in glucose levels were maintained at 72 h and 30 days. A total of 22.7% of the insulin group versus 4.4% of the standard group had biochemical hypoglycemia (with neither signs nor symptoms) in the CCU because of lower glycemic goals. However, there were no differences in symptomatic hypoglycemia or clinical outcomes between the groups.

CONCLUSIONS

A paper-based insulin algorithm targeting glucose levels of 5.0-6.5 mmol/L (90-117 mg/dL) can be feasibly implemented in the CCU. A cardiovascular outcomes trial using this approach can determine whether targeted glucose lowering improves patient outcomes.

Simultaneous copper ion removal and hydrogen production from water over a TiO₂ nanotube photocatalyst

A one-dimensional (1-D) mesoporous TiO₂ nanotube (TiNT) was successfully synthesized via a hydrothermal-calcination process, and employed in simultaneous photocatalytic Cu(2+) removal and H₂ production. Under irradiation, Cu(2+) in the wide concentration range of 8-800 ppm, could be reduced rapidly, and the reduction was not severely impacted by co-existing inorganic ions in solution. Simultaneous with Cu(2+) reduction, noticeable H₂ was produced over the in-situ fabricated Cu incorporated TiNT (Cu-TiNT) photocatalyst, while H₂ evolution rate was controlled by the Cu(2+) reduction process, due to competition of electron capture between protons and Cu(2+). In addition, H₂ generation activity of Cu-TiNT depended on the initial Cu(2+)/Ti ratio, and could be depressed by co-existing ions in solution. Fast Cu(2+) reduction and remarkable H₂ evolution confirmed the feasibility of simultaneous Cu(2+) removal and H₂ production over a TiNT photocatalyst.

Killer cell immunoglobulin-like receptors (KIR) typing by DNA sequencing

DNA sequencing is a powerful technique for identifying allelic variation within the natural killer cell immunoglobulin-like receptor genes. Because of the relatively large size of the KIR genes, each locus is amplified in two or more overlapping segments. Sanger sequencing of each gene from a preparation containing one or two alleles yields a sequence that is used to identify the alleles by comparison with a reference database.

Rationale and design of the coronary artery bypass grafting surgery off or on pump revascularization study: a large international randomized trial in cardiac surgery

BACKGROUND

Uncertainty remains regarding the benefits and risks of the technique of operating on a beating heart (off pump) for coronary artery bypass grafting (CABG) surgery versus on-pump CABG. Prior trials had few events and relatively short follow-up. There is a need for a large randomized, controlled trial with long-term follow-up to inform both the short- and long-term impact of the 2 approaches to CABG.

METHODS

We plan to randomize 4,700 patients in whom CABG is planned to undergo the procedure on pump or off pump. The coprimary outcomes are a composite of total mortality, myocardial infarction (MI), stroke, and renal failure at 30 days and a composite of total mortality, MI, stroke, renal failure, and repeat revascularization at 5 years. We will also undertake a cost-effectiveness analysis at 30 days and 5 years after CABG surgery. Other outcomes include neurocognitive dysfunction, recurrence of angina, cardiovascular mortality, blood transfusions, and quality of life.

RESULTS

As of May 3, 2011, CORONARY has recruited >3,884 patients from 79 centers in 19 countries. Currently, patient's mean age is 67.6 years, 80.7% are men, 47.0% have a history of diabetes, 51.4% have a history of smoking, and 34.4% had a previous MI. In addition, 20.9% of patients have a left main disease, and 96.6% have double or triple vessel disease.

CONCLUSIONS

CORONARY is the largest trial yet conducted comparing off-pump CABG to on-pump CABG. Its results will lead to a better understanding of the safety and efficacy of off-pump CABG.

P3-13-11: Survival Benefit Associated with Post-Mastectomy Radiation for Node-Positive, Intermediate-Risk Breast Cancer Patients: Results of a Study from the SEER Registry Data

Background

The role of post-mastectomy radiation therapy (PMRT) for breast cancer patients with intermediate-risk (1-3 positive nodes) disease remains controversial. This Surveillance, Epidemiology, and End Results (SEER) study investigated the impact of PMRT in the intermediate-risk breast cancer patient population on cause-specific survival (CSS) and overall survival (OS). The study also investigated the impact of estrogen receptor (ER) status, which has been reported in the SEER database since 2004, on the impact of PMRT in this patient population on CSS and OS.

Methods: The SEER database was used to identify all breast cancer patients who were treated between 2004–2007, who had undergone mastectomy, and who had T1-2 tumors and 1–3 pathologically positive lymph nodes. The status of radiation therapy, ethnicity, tumor grade, TNM stage, year of diagnosis, number of LNs sampled, number of LNs positive, and estrogen/progesterone receptor status was recorded. Patients missing pathologic or treatment-related information were excluded. Statistical analysis for CSS and OS was performed using the Kaplan-Meier method and analyzed using the log-rank test. Multivariable analysis was performed using the Cox proportional hazards regression model. Statistical analyses were performed using PASW, version 18.

Results: 10,517 patients were identified, with a median follow-up of 21.8 months (range 0–47 months). 2339 patients (22.2%) received PMRT. Younger patients, increasing tumor size, increasing tumor grade, and ER negative tumors were more likely to receive PMRT. PMRT was associated with improved OS, 92.8% (95% CI 91.294.4%) versus 88.7% (95% CI 87.7−89.7%), p &lt; 0.001. However, there was no overall CSS benefit to PMRT, p = 0.197. In the subgroup with ER positive tumors, PMRT was associated with both improved OS, 95.5% (95% CI 93.9−97.1%) versus 91.0% (95% CI 90.0−92.0%), p &lt; 0.001, and improved CSS, 97.6% (95% CI 96.6−98.8%) versus 96.1% (95% CI 95.3−96.9%), p = 0.009. Multivariate analysis showed that PMRT was significantly associated with improved survival (HR 0.744, p = 0.011); increasing age, tumor grade, ER negative tumors, increasing tumor stage, and increasing positive nodal ratio were associated with increased risk of death.

Conclusion: Patients with intermediate risk breast cancer who received PMRT have improved OS compared to those who did not receive PMRT. For patients with ER positive tumors, PMRT also appears to be associated with improved CSS. Greater consideration for post-mastectomy radiation therapy use may be warranted for this patient population.

Abstract P7: The Impact of Cardiovascular Hospitalization on Mortality and Quality of Life Among 14,261 Atrial Fibrillation Patients in the ACTIVE Study

Background Cardiovascular (CV) hospitalization has been used as primary outcome in atrial fibrillation (AF) research, but remains controversial. Our aim was to provide detailed information on characteristics and impact of CV hospitalization among 14,261 patients in the ACTIVE clinical trial.

Methods Patient characteristics, mortality and time to first non-fatal CV hospitalization were measured in the ACTIVE controlled clinical trial setting. Multivariable proportional hazards regression analysis was used to determine factors associated with CV hospitalization, and to assess the independent association of CV hospitalization with all-cause mortality and quality of life using the EuroQoL scale.

Results During a median follow-up of 3 years and 11 months, 10,584 CV hospitalizations were observed, of which 9,859 were non-fatal and 725 fatal. Non-fatal CV hospitalization had occurred in 50% of patients after 4 years follow-up and was more likely to occur in patients with at baseline heart failure (relative risk (RR) = 1.32; p<0.0001), coronary artery disease (RR = 1.43; p<0.0001), an antiarrhythmic drug (RR = 1.19; p<0.0001), sinus rhythm (RR = 1.42; p<0.0001) and with a history of fainting (RR = 1.23; p<0.0001), while less likely in working patients (RR = 0.84; p<0.0001). All-cause mortality in patients with at least 1 CV hospitalization was 6.60 per 100 patient years versus 4.97 per 100 patient years in patients without CV hospitalization. In time-dependent analysis, patients with CV hospitalization had an increased risk for mortality (RR = 3.13; p<0.0001), which remained significant when adjusting for baseline risk factors (RR = 3.00; p<0.0001). Heart failure hospitalization had the strongest association with mortality (RR = 5.92; p<0.0001), while hospitalization for AF was not associated (RR = 1.08; p=0.3058). The decrease in the EuroQoL quality of life score during the study was larger in surviving patients with CV hospitalization (−0.03 ± 22) compared with remaining survivors (−0.01 ± 21; p<0.0001).

Conclusions Half of ACTIVE study patients had at least one CV hospitalization during 4 years, which was associated with increased mortality and a reduced quality of life in surviving patients. Hospitalization for AF alone was not associated with mortality.

Net clinical benefit of adding clopidogrel to aspirin therapy in patients with atrial fibrillation for whom vitamin K antagonists are unsuitable

BACKGROUND

Adding clopidogrel to aspirin therapy reduces stroke in patients with atrial fibrillation (AF) but increases hemorrhage.

OBJECTIVE

To quantify the net benefit of adding clopidogrel to aspirin therapy, accounting for differences in clinical significance between ischemic and hemorrhagic events.

DESIGN

Observational cohort study to assign the relative weighting of events and post hoc analysis of randomized trial data to assess net benefit of dual antiplatelet therapy in the ACTIVE (Atrial Fibrillation Clopidogrel Trial with Irbesartan for Prevention of Vascular Events) clinical trials.

SETTING

Global randomized clinical trial.

PATIENTS

10,041 patients with AF, 7554 of whom were not candidates for warfarin therapy.

MEASUREMENTS

Ischemic events (ischemic stroke or myocardial infarction) and hemorrhagic events (hemorrhagic stroke or subdural or extracranial bleeding), weighted by the hazard ratio for death (or death or disability) after an event relative to death (or death or disability) after ischemic stroke. The net clinical benefit of dual antiplatelet therapy in the ACTIVE A trial participants was defined as the sum of weighted event incidence with dual antiplatelet therapy subtracted from the sum of weighted event incidence on control treatment, expressed as ischemic stroke equivalents prevented per 100 patients years.

RESULTS

Adding clopidogrel to aspirin therapy prevented 0.57 ischemic stroke equivalent (95% CI, -0.12 to 1.24) per 100 patient-years of treatment when weighted by hazard for death after ischemia or hemorrhage and 0.67 ischemic stroke equivalent (CI, -0.03 to 1.18) when weighted by death or disability after ischemia or hemorrhage.

LIMITATION

No attempt was made to relate deaths used for weighting to events; disability data were missing for more than one half of patients.

CONCLUSION

Adding clopidogrel to aspirin therapy resulted in a modest net benefit among patients with AF for whom warfarin was unsuitable. The benefit would probably be clinically relevant for some patients, but estimates could not exclude the possibility of either no benefit or very small harm in this population.

PRIMARY FUNDING SOURCE

Bristol-Myers Squibb and sanofi-aventis.

Abstract P6: Vitamin K Antagonist Dosing Methods and Individual Patient Quality of INR Control in the International Active W Anticoagulation Study

Background The net benefit of vitamin K antagonists (VKAs) depends on the time spent in the therapeutic range (TTR) for the International Normalized Ratio in individual patients. Evidence-based methods are recommended by guidelines. We assessed VKA dosing methods among ACTIVE W study sites and the association with TTR in individual atrial fibrillation patients.

Methods ACTIVE W sites received a survey questionnaire after the study to assess VKA dosing methods. Univariable and multivariable linear mixed models, to account for the random effect of clinic-level survey data, were used to assess the association of dosing methods with patient TTR. Patient-level covariates in multivariable analysis were: age, sex, CHADS 2 stroke risk score, mini-mental state examination score, history of VKA use, VKA type, and use of aspirin, amiodarone and insulin.

Results The questionnaire was returned by 333 of 493 ACTIVE W sites (68%) who had at least one patient randomized to VKA. Responding sites had a higher mean study TTR than non-responding sites (64 vs. 60%; p=0.0101) and were mainly specialized in cardiology (87%). Only 28% of sites managed VKA dosing with an evidence-based method: an anticoagulation clinic, computer dosing system or patient self-management. Also taking in account (non-validated) manual algorithms, 64% of sites managed VKA dosing primarily based on clinical experience. In univariable analysis, patients achieved a higher TTR when managed by an anticoagulation clinic vs. by the study physician (67.3 vs. 62.1%; p=0.0027), when managed using a computer dosing system vs. using clinical experience (72.9 vs. 63.6%; p=0.0026), and when managed using at least one evidence-based method vs. not using evidence-based methods (67.3 vs. 62.8%; p=0.0045). However, when adding patient data in multivariable analysis, these three associations became non-significant (p-values 0.4659, 0.6555 and 0.6058, respectively).

Conclusion The use of evidence-based VKA dosing methods was reported by only 28% of ACTIVE W sites, but was not significantly associated with an improved TTR when accounting for patient characteristics.

Increased HLA class I and II diversity as 72 novel alleles are identified in volunteers for the National Marrow Donor Program Registry in 2010

Seventy-two novel human leukocyte antigen (HLA) class I and class II alleles are described from volunteers for the 'Be The Match Registry®': 17 HLA-A alleles, 12 HLA-C alleles, 31 HLA-B alleles and 12 HLA-DRB1 alleles. Forty-six (≈ 64%) of the 72 novel alleles are single-nucleotide substitution variants when compared with their most homologous allele. Five of these single-nucleotide variants are silent substitutions and one creates a non-expressed allele (B*44:108N). The remaining novel alleles differ from their most similar allele by two to five nucleotide substitutions. One of the novel HLA-C alleles (C*07:150Q) is of questionable expression due to an insertion of 21 nucleotides starting at codon 143 that adds seven amino acids to exon 3. An inter-locus gene conversion may have created the novel allele HLA-A*23:31 that shares its codon differences with HLA-B*07:28. Some of the new alleles encode novel codons and unique amino acid changes at polymorphic positions in the HLA-A (codons 116 and 150), HLA-C (codon 114), HLA-B (codons 11, 21, 35, 42, 48, 73, 98 and 170) and HLA-DRB1 (codon 29) loci.

A morphological analysis of the humeral capitellum with an interest in prosthesis design

INTRODUCTION

Although interest in capitellar arthroplasty is increasing, the morphology of the capitellum has not been fully characterized. Our purpose was to quantify the anthropometric features of the capitellum with an interest in arthroplasty design. We hypothesized that the shape is more complex than originally believed, and cannot be accurately modeled as a spherical structure.

METHODS

Fifty cadaveric human elbows underwent helical computer tomography scans. After reconstruction and establishment of a coordinate system for the distal humerus, circle-fits were applied to each of the 1-mm-thick slices. Sagittal radii of curvature were calculated every 10° of flexion around each circle (0-130° of flexion). A single transverse radius was calculated at 60° of flexion. The surface of the capitellum was described by sagittal and transverse radii of curvature and the footprint by height and width. These pairs of parameters were correlated to determine their strength of association.

RESULTS

The average height was 23.2 ± 2.9 mm (range, 18.3-29.5), while the average width was 13.9 ± 2.3 (range, 9-19). The sagittal radius of curvature was 11.6 ± 1.4 mm (range, 8.7-14.8), and the transverse radius was 14.0 ± 3.0 mm (range, 9.6-20.9). Correlations of height and width and sagittal and transverse radii were significant (R = .547, .705) (P < .01). Sagittal and transverse radii and height and width were significantly different (P < .001 for each pair).

CONCLUSION

The capitellum does not have a spherical surface or a circular footprint. There is substantial variability in the relationship between the height and width, and between the surface radii, that may be difficult to replicate with an off-the-shelf implant.

The effect of extensive flooding in Hull on the glycaemic control of patients with diabetes

AIMS

To examine the impact of extensive flooding in a UK city in 2007 on the glycaemic control of patients with diabetes mellitus.

METHODS

This was a longitudinal study in patients with diabetes mellitus 12 months before and after the floods in Hull and East Yorkshire, UK. All patients registered with diabetes mellitus were sent questionnaires about their experiences during and after the floods. Glycaemic control for patients directly affected by the floods was compared against those unaffected.

RESULTS

Of 1743 respondents, 296 patients had been affected by the floods (110 insulin treated, 186 lifestyle and oral agents) and 1447 unaffected (482 insulin treated, 965 lifestyle and oral agents). There was a rise in mean HbA(1c) of affected individuals comparing 12 months before the floods with 12 months after [mean (95% confidence interval), 7.6% (7.5-7.7) vs. 7.9% (7.7-8.0), P = 0.002], but not those unaffected [7.5% (7.4-7.6) vs. 7.5% (7.4-7.6), P = 0.46]. The difference was mainly in insulin-treated patients [8.6% (8.3, 8.9) affected vs. 8.2% (8.1, 8.3) unaffected, (P = 0.002)].

CONCLUSIONS

Glycaemic control deteriorated in diabetes patients following the floods but was almost exclusively confined to patients taking insulin and was worst at 6-9 months following the event. Insulin-treated patients may need specific targeting in the event of a natural disaster.

Kinetic structure of the electron diffusion region in antiparallel magnetic reconnection

Strong electron pressure anisotropy has been observed upstream of electron diffusion regions during reconnection in Earth's magnetotail and kinetic simulations. For collisionless antiparallel reconnection, we find that the anisotropy drives the electron current in the electron diffusion region, and that this current is insensitive to the reconnection electric field. Reconstruction of the electron distribution function within this region at enhanced resolutions reveals its highly structured nature and the mechanism by which the pressure anisotropy sets the structure of the region.