bluuebunny/crossref_metadata_2025 huggingface dataset:
The Cardiotomy Trial
Authors: Rubens Fraser D. , Boodhwani Munir , Mesana Thierry , Wozny Denise , Wells George , Nathan Howard J.
Published: September 2007

Background—

Reinfusion of unprocessed cardiotomy blood during cardiac surgery can introduce particulate material into the cardiopulmonary bypass circuit, which may contribute to postoperative cognitive dysfunction. On the other hand, processing of this blood by centrifugation and filtration removes coagulation factors and may potentially contribute to coagulopathy. We sought to evaluate the effects of cardiotomy blood processing on blood product use and neurocognitive functioning after cardiac surgery.

Methods and Results—

Patients undergoing coronary and/or aortic valve surgery using cardiopulmonary bypass were randomized to receive unprocessed blood (control, n=134) or cardiotomy blood that had been processed by centrifugal washing and lipid filtration (treatment, n=132). Patients and treating physicians were blinded to treatment assignment. A strict transfusion protocol was followed. Blood transfusion data were analyzed using Poisson regression models. The treatment group received more intraoperative red blood cell transfusions (0.23±0.69 U versus 0.08±0.34 U,
P
=0.004). Both red blood cell and nonred blood cell blood product use was greater in the treatment group and postoperative bleeding was greater in the treatment group. Patients were monitored intraoperatively by transcranial Doppler and they underwent neuropsychometric testing before surgery and at 5 days and 3 months after surgery. There was no difference in the incidence of postoperative cognitive dysfunction in the 2 groups (relative risk: 1.16, 95% CI: 0.86 to 1.57 at 5 days postoperatively; relative risk: 1.05, 95% CI: 0.58 to 1.90 at 3 months). There was no difference in the quality of life nor was there a difference in the number of emboli detected in the 2 groups.

Conclusions—

Contrary to expectations, processing of cardiotomy blood before reinfusion results in greater blood product use with greater postoperative bleeding in patients undergoing cardiac surgery. There is no clinical evidence of any neurologic benefit with this approach in terms of postoperative cognitive function.
Remote Ischemic Preconditioning Reduces Myocardial and Renal Injury After Elective Abdominal Aortic Aneurysm Repair
Authors: Ali Ziad A. , Callaghan Chris J. , Lim Eric , Ali Ayyaz A. , Reza Nouraei S.A. , Akthar Asim M. , Boyle Jonathan R. , Varty Kevin , Kharbanda Rajesh K. , Dutka David P. , Gaunt Michael E.
Published: September 2007

Background—

Myocardial and renal injury commonly contribute to perioperative morbidity and mortality after abdominal aortic aneurysm repair. Remote ischemic preconditioning (RIPC) is a phenomenon whereby brief periods of ischemia followed by reperfusion in one organ provide systemic protection from prolonged ischemia. To investigate whether remote preconditioning reduces the incidence of myocardial and renal injury in patients undergoing elective open abdominal aortic aneurysm repair, we performed a randomized trial.

Method and Results—

Eighty-two patients were randomized to abdominal aortic aneurysm repair with RIPC or conventional abdominal aortic aneurysm repair (control). Two cycles of intermittent crossclamping of the common iliac artery with 10 minutes ischemia followed by 10 minutes reperfusion served as the RIPC stimulus. Myocardial injury was assessed by cardiac troponin I (>0.40 ng/mL), myocardial infarction by the American College of Cardiology/American Heart Association definition and renal injury by serum creatinine (>177 μmol/L) according to American Heart Association guidelines for risk stratification in major vascular surgery. The groups were well matched for baseline characteristics. RIPC reduced the incidence of myocardial injury by 27% (39% versus 12% [95% CI: 8.8% to 45%];
P
=0.005), myocardial infarction by 22% (27% versus 5% [95% CI: 7.3% to 38%];
P
=0.006), and renal impairment by 23% (30% versus 7%; [95% CI: 6.4 to 39];
P
=0.009). Multivariable analysis revealed the protective effect of RIPC on myocardial injury (OR: 0.22, 95% CI: 0.07 to 0.67;
P
=0.008), myocardial infarction (OR: 0.18, 95% CI: 0.04 to 0.75;
P
=0.006) and renal impairment were independent of other covariables.

Conclusions—

In patients undergoing elective open abdominal aortic aneurysm repair, RIPC reduces the incidence of postoperative myocardial injury, myocardial infarction, and renal impairment.
The
MBL2
‘LYQA Secretor’ Haplotype Is an Independent Predictor of Postoperative Myocardial Infarction in Whites Undergoing Coronary Artery Bypass Graft Surgery
Authors: Collard Charles D. , Shernan Stanton K. , Fox Amanda A. , Bernig Toralf , Chanock Stephen J. , Vaughn William K. , Takahashi Kazue , Ezekowitz Alan B. , Jarolim Petr , Body Simon C.
Published: September 2007

Background—

Mannose-binding lectin (MBL) is an important component of innate immunity and activator of the lectin complement pathway. Within the
MBL2
gene are seven 5′ “secretor” haplotypes that code for altered serum MBL levels and complement activation. However, recent evidence suggests that 3′
MBL2
haplotypes may also modify MBL function and circulating levels. Because MBL and the lectin complement pathway have been implicated in cardiovascular injury, we investigated whether
MBL2
haplotypes are independently associated with an increased risk of postoperative myocardial infarction (PMI) in patients undergoing coronary artery bypass graft surgery.

Methods and Results—

Genotyping of 18 polymorphic sites within the
MBL2
gene was performed in a prospective, longitudinal multi-institutional study of 978 patients undergoing primary coronary artery bypass graft-only surgery with cardiopulmonary bypass between August 2001 and May 2005. After adjustment for multiple comparisons by permutation testing, multivariate, stepwise logistic regression, including a score test, was performed controlling for patient demographics, preoperative risk factors, medications, and intraoperative variables to determine if
MBL2
secretor haplotypes are independent predictors of PMI in whites undergoing primary coronary artery bypass graft surgery. Neither the 5′ nor 3′
MBL2
haplotypes alone were associated with an increased incidence of PMI. However, the incidence of PMI in whites (n=843) expressing the combined
MBL2
5′ LYQA secretor haplotype (CGTCGG) and 3′ haplotype (CGGGT) was significantly higher than in whites not expressing the haplotype (38% versus 10%;
P
<0.007). Moreover, the combined
MBL2
LYQA secretor haplotype was an independent predictor of PMI in whites after primary coronary artery bypass graft surgery after adjustment for other covariates (
P
<0.02; adjusted OR: 3.97; 95% CI: 1.30 to 12.07). The combined
MBL2
LYQA secretor haplotype in whites was also an independent predictor of postoperative CKMB levels exceeding 60 ng/mL (
P
<0.02; adjusted OR: 4.48; 95% CI: 1.95 to 16.80). Inclusion of the combined
MBL2
LYQA secretor haplotype improved prediction models for PMI based on traditional risk factors alone (C-statistic 0.715 versus 0.705).

Conclusions—

The combined
MBL2
LYQA secretor haplotype is a novel independent predictor of PMI and may aid in preoperative risk stratification of whites undergoing primary coronary artery bypass graft surgery.
Development of a Biological Ventricular Assist Device
Authors: Yildirim Yalin , Naito Hiroshi , Didié Michael , Karikkineth Bijoy Chandapillai , Biermann Daniel , Eschenhagen Thomas , Zimmermann Wolfram-Hubertus
Published: September 2007

Background—

Engineered heart tissue (EHT) can be generated from cardiomyocytes and extracellular matrix proteins and used to repair local heart muscle defects in vivo. Here, we hypothesized that pouch-like heart muscle constructs can be generated by using a novel EHT-casting technology and applied as heart-embracing cardiac grafts in vivo.

Methods and Results—

Pouch-like EHTs (inner/outer diameter: 10/12 mm) can be generated mainly from neonatal rat heart cells, collagen type I, and serum containing culture medium. They contain a dense network of connexin 43 interconnected cardiomyocytes and an endo-/epicardial surface lining composed of prolylhydroxylase positive cells. Pouch-like EHTs beat spontaneously and show contractile properties of native heart muscle including positive inotropic responses to calcium and isoprenaline. First implantation studies indicate that pouch-like EHTs can be slipped over uninjured adult rat hearts to completely cover the left and right ventricles. Fourteen days after implantation, EHT-grafts stably covered the epicardial surface of the respective hearts. Engrafted EHTs were composed of matrix and differentiated cardiac muscle as well as newly formed vessels which were partly donor-derived.

Conclusions—

Pouch-like EHTs can be generated with structural and functional properties of native myocardium. Implantation studies demonstrated their applicability as cardiac muscle grafts, setting the stage for an evaluation of EHT-pouches as biological ventricular assist devices in vivo.
Persistent Reduction of Ischemic Mitral Regurgitation by Papillary Muscle Repositioning
Authors: Hung Judy , Chaput Miguel , Guerrero J. Luis , Handschumacher Mark D. , Papakostas Lampros , Sullivan Suzanne , Solis Jorge , Levine Robert A.
Published: September 2007

Background—

Recurrent ischemic mitral regurgitation (IMR) is frequent despite initial reduction by annuloplasty because continued LV remodeling increases tethering to the infarcted papillary muscle (PM). We have previously shown that PM repositioning by an external patch device can acutely reduce IMR. In this study, we tested the hypothesis that IMR reduction persists despite possible continued LV remodeling.

Methods and Results—

In 7 sheep, we used a chronic ischemic posterior infarct model that produces LV dilatation and MR over 10 weeks. An epicardial patch device was adjusted under echo guidance to reduce MR, with follow-up over a further 8 weeks and evaluation by 3D echo and sonomicrometry. In all 7 sheep, moderate IMR resolved with acute patch application and PM repositioning (6.5±1.8 mm to 0.6±1.3 mm proximal jet width,
P
<0.001) without decrease in LVEF (43±3% to 44±8%). Eight weeks after PM repositioning, MR was not significantly greater (0.6±1.3 mm versus 1.0±1.0 mm,
P
=NS) despite an increase in LV volumes in 3 animals (2 had increases of 50±15%). On average, LV volumes did not change significantly (ESV: 46±8 mL versus 49±15 mL;
P
=NS and EDV: 85±16 mL versus 89±30 mL;
P
=NS). LVEF was unchanged from acute to chronic patch (44±8% versus 43±8%). Contractility as end-systolic elastance did not decrease from the chronic MI to the acute and chronic patch stages, nor were there any significant changes in dP/dt, LV stiffness constant, or time constant of LV relaxation (Tau).

Conclusion—

PM repositioning is persistently effective in reducing moderate chronic IMR, even when LV volume increases. This may reflect structural stabilization by an external patch device of the papillary muscle-LV wall complex that controls mitral valve tethering.
Transplantation of Nanoparticle Transfected Skeletal Myoblasts Overexpressing Vascular Endothelial Growth Factor-165 for Cardiac Repair
Authors: Ye Lei , Kh Haider Husnain , Tan RuSan , Toh WeeChi , Law Peter K. , Tan WeeBeng , Su LiPing , Zhang Wei , Ge RuoWen , Zhang Yong , Lim YeanTeng , Sim Eugene K.W.
Published: September 2007

Background—

We investigated the feasibility and efficacy of polyethylenimine (PEI) based human vascular endothelial growth factor-165 (hVEGF
165
) gene transfer into human skeletal myoblasts (HSM) for cell based delivery to the infarcted myocardium.

Methods and Results—

Based on optimized transfection procedure using enhanced green fluorescent protein (pEGFP), HSM were transfected with plasmid-hVEGF
165
(phVEGF
165
) carried by PEI (PEI- phVEGF
165
) nanoparticles. The transfected HSM were characterized for transfection and expression of hVEGF
165
in vitro and transplanted into rat heart model of acute myocardial infarction (AMI): group-1=DMEM injection, group-2= HSM transplantation, group-3= PEI-phVEGF
165
–transfected HSM (PEI-phVEGF
165
myoblast) transplantation. A total of 48 rats received cyclosporine injection from 3 days before and until 4 weeks after cell transplantation. Echocardiography was performed to assess the heart function. Animals were sacrificed for molecular and histological studies on the heart tissue at 4 weeks after treatment. Based on optimized transfection conditions, transfected HSM expressed hVEGF
165
for 18 days with >90% cell viability in vitro. Apoptotic index was reduced in group-2 and group-3 as compared with group-1. Blood vessel density (×400) by immunostaining for PECAM-1 in group-3 was significantly higher (
P
=0.043 for both) as compared with group-1 and group-2 at 4 weeks. Regional blood flow (ml/min/g) in the left ventricular anterior wall was higher in group-3 (
P
=0.043 for both) as compared with group-1 and group-2. Improved ejection fraction was achieved in group-3 (58.44±4.92%) as compared with group-1 (
P
=0.004).

Conclusion—

PEI nanoparticle mediated hVEGF
165
gene transfer into HSM is feasible and safe. It may serve as a novel and efficient alternative for angiomyogenesis in cardiac repair.
Endoscopic Mitral and Tricuspid Valve Surgery After Previous Cardiac Surgery
Authors: Casselman Filip P. , La Meir Mark , Jeanmart Hughes , Mazzarro Enzo , Coddens Jose , Van Praet Frank , Wellens Francis , Vermeulen Yvette , Vanermen Hugo
Published: September 2007

Background—

The purpose of this study was to evaluate the feasibility and effectiveness of a right video-assisted approach for atrioventricular valve disease after previous cardiac surgery.

Methods and Results—

Between December 1st 1997 and May 1st 2006, 80 adults (mean age 65±12 years; 56% female) underwent reoperative surgery using a video-assisted approach without rib spreading. Previous cardiac operations included mitral valve (39%), CABG (29%), congenital (10%), and other (23%). For 25% of patients, this was at least their third cardiac operation. Mean time to redo surgery was 15±12 years. Femoral vessel cannulation and endoaortic clamping were routinely used. Mean preoperative Euroscore was 9.0±2.7 (5 to 20) and predicted mortality was 16.0±14.2% (4 to 86). Median preoperative NYHA class was II and mean follow-up was 25±22 months. Lung adhesions necessitated sternotomy in 4 cases and cannulation problems in another patient. Total operative mortality was 3.8% (n=3), O/E for mortality being 0.24. Procedures were mitral valve repair (45%; n=36), replacement (50%; n=40) and tricuspid valve replacement (5%; n=4). Additional procedures were performed in 44% (n=35). Mean aortic crossclamp and procedure time were 92±37 and 267±64 minutes. Mean postoperative blood loss was 815±1083 mL. Postoperative morbidity included 2 strokes (2.5%). Mean hospital stay was 10.7±6.7 days. Survival at 1 and 4 years was 93.6±2.8% and 85.6±6.4%. There was 1 late reoperation at 5 years. Median NYHA class at follow-up was II. When comparing, all but 1 patient (98.8%) preferred their minimally invasive approach when considering perioperative pain, postoperative rehabilitation, and final esthetic result.

Conclusions—

Video-assisted minimal access correction of atrioventricular valve disease after previous cardiac surgery is not only feasible but had lower than predicted mortality and strong patient satisfaction. It should therefore be used more frequently in today’s practice.
Effect of Chronotropy and Inotropy on Stitch Tension in the Edge-to-Edge Mitral Repair
Authors: Timek Tomasz A. , Nielsen Sten L. , Lai David T. , Liang David , Daughters George T. , Ingels Neil B. , Miller D. Craig
Published: September 2007

Background—

Our prior studies suggest that mitral annular septal-lateral (SL) diameter is the chief determinant of “Alfieri stitch” tension, but hemodynamic parameters may also play a role. We approximated the central edge of the mitral leaflets with a miniature force transducer to measure tension (T) at the leaflet approximation point during inotropic and chronotropic stimulation.

Methods and Results—

Eight sheep were studied under open-chest conditions immediately after surgical placement of a miniature force transducer to approximate the leaflets and implantation of radiopaque markers on the LV and mitral annulus (MA). Chronotropic stimulation was induced with atrial pacing at 130 minutes
−1
(n=5) whereas inotropic state was increased with IV CaCl
2
bolus (n=8). Hemodynamic data, stitch tension, and 3-D marker coordinates were obtained throughout the cardiac cycle before and during each intervention. Peak stitch tension (T
MAX
) under all conditions was observed in diastole and temporally correlated with peak annular SL (SL
MAX
) size. Atrial pacing did not change peak transducer tension or annular size. Calcium infusion also did not alter peak transducer tension (0.29±0.11 versus 0.32±0.10 N;
P
=NS) and only slightly reduced SL dimension (29.9±3.3 versus 29.3±3.5 mm;
P
<0.05).

Conclusion—

Isolated increase in heart rate or inotropic state did not alter peak stitch tension whereas enhanced contractile state decreased SL diameter minimally. These data, combined with those from our previous study, suggest that geometric (SL diameter) rather than hemodynamic parameters are the main determinants of “Alfieri stitch” tension. This implies that any interventional or surgical edge-to-edge repair performed without concomitant annular reduction to limit the SL dimension could expose the leaflet junction to forces which could limit repair durability.
Nonlinear Power Loss During Exercise in Single-Ventricle Patients After the Fontan
Authors: Whitehead Kevin K. , Pekkan Kerem , Kitajima Hiroumi D. , Paridon Stephen M. , Yoganathan Ajit P. , Fogel Mark A.
Published: September 2007

Background—

We previously demonstrated that power loss (PL) through the total cavopulmonary connection (TCPC) in single-ventricle patients undergoing Fontan can be calculated by computational fluid dynamic analysis using 3-dimensional MRI anatomic reconstructions. PL through the TCPC may play a role in single-ventricle physiology and is a function of cardiac output. We hypothesized that PL through the TCPC increases significantly under exercise flow conditions.

Methods and Results—

MRI data of 10 patients with a TCPC were analyzed to obtain 3-dimensional geometry and flow rates through the superior vena cava, inferior vena cava, left pulmonary artery, and right pulmonary artery. Steady computational fluid dynamic simulations were performed at baseline conditions using MRI-derived flows. Simulated exercise conditions of twice (2×) and three times (3×) baseline flow were performed by increasing inferior vena cava flow. PL, head loss, and effective resistance through the TCPC were calculated for each condition. Each condition was repeated at left pulmonary artery/right pulmonary artery ratios of 30/70 and 70/30 to determine the effects of pulmonary flow splits on exercise PL. For each patient, PL increases dramatically in a nonlinear fashion with increasing cardiac output, even when normalized to calculate head loss or resistance. Flow splits had a significant effect on PL at exercise, with most geometries favoring right pulmonary artery flow.

Conclusions—

The relationship between cardiac output and PL is nonlinear and highly dependent on TCPC geometry and pulmonary flow splits. This study demonstrates the importance of studying the TCPC under exercise conditions, because baseline conditions may not adequately characterize TCPC efficiency.
Early Repair of Moderate Ischemic Mitral Regurgitation Reverses Left Ventricular Remodeling
Authors: Beeri Ronen , Yosefy Chaim , Guerrero J. Luis , Abedat Suzan , Handschumacher Mark D. , Stroud Robert E. , Sullivan Suzanne , Chaput Miguel , Gilon Dan , Vlahakes Gus J. , Spinale Francis G. , Hajjar Roger J. , Levine Robert A.
Published: September 2007

Background—

Mitral regurgitation (MR) doubles postmyocardial infarction (MI) mortality. We have shown that moderate MR augments remodeling in an apical MI model (no intrinsic MR) with independent left ventricle-to-left atrial MR-type flow. We hypothesized that repairing moderate MR 1 month after MI reverses this remodeling.

Methods and Results—

Anteroapical MIs were created in 18 sheep, and a left ventricle-to-left atrial shunt implanted in 12 (regurgitant fraction, 30%). Six sheep had the shunt closed at 1 month (repair group). Sheep were compared at baseline, and at 1 and 3 months. Sheep in the MI+MR (unrepaired) and repaired groups remodeled during the first month (120% increased left ventricular end-systolic volume [ESV;
P
<0.01]), but shunt closure reversed remodeling at 3 months, with end-diastolic volume (EDV) and ESV 135% and 128% of baseline versus 220% and 280% without repair (
P
<0.001). At 3 months, dP/dt and preload-recruitable stroke work were relatively maintained in the repaired and MI-only groups versus nearly 50% decreases without repair. Prohypertrophic gp130 and antiapoptotic pAkt increased followed by exhaustion below baseline without repair, but remained elevated at 3 months with repair or MI only. With repair, matrix metalloproteinase-2 decreased to ≤50% that without repair in remote and border zones at 3 months, and the matrix metalloproteinase inhibitor TIMP-4 increased dramatically.

Conclusions—

Early repair of moderate MR in the setting of apical MI substantially reverses the otherwise progressive remodeling process, with reduced left ventricular volumes, relatively maintained contractility, persistently activated intracellular signals promoting hypertrophy and opposing apoptosis, and reduced matrix proteolytic activity. These findings are of interest for the current controversy regarding potential benefits of repair of MR after MI.
Atherosclerosis Secondary Prevention Performance Measures After Coronary Bypass Graft Surgery Compared With Percutaneous Catheter Intervention and Nonintervention Patients in the Get With the Guidelines Database
Authors: Hiratzka Loren F. , Eagle Kim A. , Liang Li , Fonarow Gregg C. , LaBresh Kenneth A. , Peterson Eric D.
Published: September 2007

Background—

The American Heart Association Get With the Guidelines-Coronary Artery Disease program facilitates patient and physician compliance with proven atherosclerosis risk reduction strategies with collaborative learning sessions, teaching materials, predischarge online check lists, and web-based performance measure feedback for continuous quality improvement. Patients having coronary artery bypass graft surgery (CABG) may be subject to different care processes, nursing unit pathways, and personnel than patients having percutaneous catheter intervention or neither intervention, which may affect compliance.

Methods and Results—

The Get With the Guidelines-Coronary Artery Disease database was queried to determine whether compliance with secondary prevention performance measures for CABG patients was different from that for nonsurgical patients. A total of 119 106 patients were treated with CABG (14 118), percutaneous catheter intervention (58 702), or neither intervention (46 286). Compliance with medication prescriptions, including aspirin, β-blockers, angiotensin-converting enzyme inhibitors, and lipid-lowering drugs, and smoking cessation counseling for eligible patients was analyzed. Medically appropriate exclusions and contraindications were included in the analysis. After adjusting for 14 clinical variables, CABG patients were less likely to receive most secondary prevention measures relative to percutaneous catheter intervention patients. In contrast, CABG patients were more likely to receive aspirin, β-blocker, and smoking cessation counseling than neither intervention patients. Composite adherence and defect-free rates were highest for percutaneous catheter intervention patients and lowest for neither intervention patients after adjustment.

Conclusions—

There are significant differences in compliance at hospital discharge with secondary prevention performance measures for CABG patients compared with nonsurgical patients. Process of care differences may explain these differences and should be examined further because significant opportunities for improved compliance are evident. CABG patients in particular represent a group for whom secondary prevention has proven benefits, and they may benefit from future quality improvement interventions.
Obesity and Metabolic Syndrome Are Independent Risk Factors for Atrial Fibrillation After Coronary Artery Bypass Graft Surgery
Authors: Echahidi Najmeddine , Mohty Dania , Pibarot Philippe , Després Jean-Pierre , O’Hara Gilles , Champagne Jean , Philippon François , Daleau Pascal , Voisine Pierre , Mathieu Patrick
Published: September 2007

Background—

Postoperative atrial fibrillation (POAF) is a highly prevalent complication after cardiac surgery with substantial effects on outcomes. Previous studies have reported that obesity is a risk factor for POAF after cardiac surgery. However, it is unknown whether the metabolic syndrome (MS) also increases the risk of postoperative atrial fibrillation.

Methods and Results—

We retrospectively analyzed the association between obesity and MS and the incidence of new-onset POAF in a total of 5085 patients who underwent isolated coronary artery bypass grafting surgery with no concomitant valvular surgery. Of these patients, 1468 (29%) were obese (body mass index ≥30 kg/m
2
) and 2320 (46%) had a MS as defined by the NCEP-ATPIII. POAF occurred in 1374 (27%) of the patients. Obesity was associated (
P
<0.001) with increased incidence of POAF in the whole cohort as well as in patients >50 years old but not in patients ≤50 years old. In these patients, MS was the only metabolic factor to be significantly associated with higher incidence of POAF (12% versus 6%,
P
=0.01). In >50-year-old patients, mild (30 ≤ body mass index <35 kg/m
2
) and moderate–severe (body mass index ≥35 kg/m
2
) obesity were independently associated with a 1.4-fold (95% CI: 1.10 to 1.71;
P
=0.004) and 2.3-fold (95% CI: 1.71 to 3.13;
P
<0.0001) increase in the risk of POAF, respectively. In ≤50-year-old patients, MS (relative risk [RR]: 2.36; 95% CI: 1.10 to 5.12;
P
=0.02) but not obesity was independently associated with POAF.

Conclusion—

This study demonstrates that obesity is a powerful risk factor for the occurrence of POAF after isolated coronary artery bypass grafting surgery in patients older than 50 years. However, in the younger population, this association is not observed and MS is the only metabolic risk factor to be independently associated with POAF.
Long-Term Impact of Diabetes and Its Comorbidities in Patients Undergoing Isolated Primary Coronary Artery Bypass Graft Surgery
Authors: Mohammadi Siamak , Dagenais François , Mathieu Patrick , Kingma John G. , Doyle Daniel , Lopez Stephane , Baillot Richard , Perron Jean , Charbonneau Eric , Dumont Eric , Metras Jacques , Desaulniers Denis , Voisine Pierre
Published: September 2007

Background—

The objective of this study was to identify the impact of diabetes and related comorbidities, namely chronic renal failure, peripheral vascular disease, and low ejection fraction (<35%), on long-term survival of patients undergoing coronary artery bypass graft surgery.

Methods and Results—

A unicenter study was conducted on 9125 survivors of isolated coronary artery bypass graft surgery between 1992 and 2002. There were 6581 nondiabetic patients and 2544 diabetics, including 1809 patients with noninsulin-dependent diabetes mellitus and 735 patients with insulin-dependent diabetes mellitus. Cardiac-specific survival at 5 and 10 years was lower in insulin-dependent diabetes mellitus compared with both nondiabetic mellitus patients and patients with noninsulin-dependent diabetes mellitus (
P
<0.0001). However, freedom from cardiac-related death was similar for patients with noninsulin-dependent diabetes mellitus and nondiabetes mellitus patients up to 6 years (
P
=0 0.08) after surgery and was significantly lower thereafter (
P
=0.004). Cardiac-specific survival after coronary artery bypass graft surgery in patients with one or more comorbidities was comparable (
P
=0.4) for both nondiabetes mellitus patients and patients with noninsulin-dependent diabetes mellitus, but was significantly lower for those requiring insulin therapy (
P
<0.0001). Noninsulin-dependent diabetes mellitus was not an independent predictor of long-term cardiac death (hazard ratio: 1.09,
P
=0.41); however, insulin-dependent diabetes mellitus, chronic renal failure, peripheral vascular disease, and low ejection fraction were all independent risk factors for late cardiac death (all
P
<0.0001). The impact of comorbidities on the long-term risk of cardiac death was similar for the 3 groups.

Conclusions—

Noninsulin-dependent diabetes is not an independent predictor of late cardiac death after coronary artery bypass graft surgery, because cardiac-related survival is similar to that of nondiabetic patients for 6 years after surgery. In diabetic and nondiabetic patients, cardiac survival is adversely affected by the need for insulin therapy and/or the presence and number of comorbidities such as chronic renal failure, peripheral vascular disease, and low ejection fraction.
Differential Protein Kinase C Isoform Abundance in Ascending Aortic Aneurysms From Patients With Bicuspid Versus Tricuspid Aortic Valves
Authors: Jones Jeffrey A. , Stroud Robert E. , Kaplan Brooke S. , Leone Allyson M. , Bavaria Joseph E. , Gorman Joseph H. , Gorman Robert C. , Ikonomidis John S.
Published: September 2007

Background—

It is recognized that different events contribute to the initiation of ascending thoracic aortic aneurysms (ATAAs) in patients with bicuspid aortic valves (BAV) versus patients with tricuspid aortic valves (TAV), but the molecular signaling pathways driving aneurysm formation remain unclear. Protein kinase C (PKC) is a superfamily of kinases which differentially mediate signaling events that lead to altered gene expression and cellular function, and may regulate downstream mediators of vascular remodeling. The present study tested the hypothesis that ATAA development in patients with BAV versus TAV proceeds by independent signaling pathways involving differential PKC signaling.

Methods and Results—

ATAA samples were collected from BAV (n=57) and TAV (n=55) patients and assessed for 10 different PKC isoforms by immunoblotting. Results were expressed as a percent change in abundance (mean±SEM) from a nonaneurysmal control group (100%, n=21). Correlation analysis was performed, and relationships between PKC and matrix metalloproteinase abundance were reported. In the BAV group, classic and novel PKC isoforms (PKC-α, βΙ, γ, ε, θ) were increased, whereas PKC-η and atypical PKC-ζ were decreased. In the TAV group, classic and novel isoforms were decreased and atypical PKC-ζ was elevated. Positive correlations between PKC and matrix metalloproteinase abundance were identified.

Conclusions—

Differential PKC isoform abundance was observed in ATAA samples from patients with BAV versus TAV, suggesting independent molecular signaling pathways may be operative. Induction of independent transcriptional programs may result and may provide a mechanistic foundation for developing selective diagnostic/therapeutic strategies for patients with ATAAs secondary to BAV or TAV.
Aprotinin Does Not Increase the Risk of Renal Failure in Cardiac Surgery Patients
Authors: Furnary Anthony P. , Wu YingXing , Hiratzka Loren F. , Grunkemeier Gary L. , Page U. Scott
Published: September 2007

Background—

Aprotinin is frequently used in high-risk cardiac surgery patients to decrease bleeding complications and transfusions of packed red blood cells (PRBC). Transfusions of PRBC are known to directly increase the risk of new onset postoperative renal failure (ARF) in cardiac surgery patients. A recent highly publicized report implicated aprotinin as an independent causal factor for postoperative renal failure, but ignored the potential confounding affect of numerical PRBC data on ARF. We sought to investigate that claim with an analysis that included all perioperative risk factors for renal failure, including PRBC transfusion data.

Methods and Results—

Prospectively collected patient data from 12 centers contributing to the Merged Cardiac Registry, an international multicenter cardiac surgery database, operated on between January 2000 and February 2006 were retrospectively analyzed. A previously published risk model for ARF incorporating 12 variables was used to calculate a baseline ARF risk score for each patient in whom those variables were available (n=15 174). After adding transfused PRBC data 11 198 patients remained for risk-adjusted assessment of ARF in relation to aprotinin use. Risk-adjusted multivariable analyses were carried out with, and without, consideration of transfused PRBC. Aprotinin was used in 24.6% (2757/11 198). The overall incidence of ARF was 1.6% (180/11 198) and was higher in the aprotinin subset (2.6%, 72/2757 versus 1.3%, 108/8441;
P
<0.001). The incidence of ARF directly and significantly increased with increasing transfusions of PRBC (
P
<0.001). Risk-adjusted analysis without transfused PRBC in the model suggests that aprotinin significantly impacts ARF (
P
=0.008; OR=1.5). However, further risk adjustment with the addition of the highly significant transfused PRBC variable (
P
<0.0001; OR=1.23/transfused PRBC) to the model attenuates the purported independent affect of aprotinin (
P
=0.231) on ARF.

Conclusions—

The increase in renal failure seen in patients who were administered aprotinin was directly related to increased number of transfusions in that high-risk patient population. Aprotinin use does not independently increase the risk of renal failure in cardiac surgery patients.
A Benchmark for Evaluating Innovative Treatment of Left Main Coronary Disease
Authors: Sabik Joseph F. , Blackstone Eugene H. , Firstenberg Michael , Lytle Bruce W.
Published: September 2007

Background—

Left main trunk stenosis (≥50%) has traditionally been treated with coronary artery bypass grafting. Improvements in coronary stents have led some to advocate percutaneous coronary intervention. To provide a benchmark of outcomes against which percutaneous coronary intervention may be compared, we (1) assessed survival and freedom from coronary reintervention after coronary artery bypass grafting in these patients and (2) identified their risk factors.

Methods and Results—

From 1971 to 1998, the first 1000 primary coronary artery bypass grafting patients (n=26 927) were followed every 5 years. Of these, 3803 had left main trunk stenosis ≥50%. A multivariable, nonproportional hazards, time-related analysis was performed to model survival and freedom from coronary reintervention (percutaneous coronary intervention or reoperation) and to identify their risk factors. Survival at 30 days, 1, 5, 10, 15, and 20 years was 97.6%, 93.6%, 83%, 64%, 44%, and 28%, respectively, and freedom from coronary reintervention was 99.7%, 98.9%, 96.6%, 89%, 76%, and 61%, respectively. Worse left ventricular function (
P
<0.0001), diabetes (
P
<0.0001), hypertension (
P
<0.001), peripheral arterial disease (
P
=0.0002), smoking (
P
<0.0001), and elevated triglycerides (
P
=0.01) decreased survival, and younger age (
P
<0.0001), elevated triglycerides (
P=
0.005), and incomplete revascularization (
P=
0.003) increased coronary reintervention. Internal thoracic artery grafting of the left anterior descending improved survival and decreased coronary reintervention.

Conclusions—

This study provides a 20-year outcome benchmark for surgical treatment of left main trunk disease. It indicates that simple comparisons of new treatments are inadequate without risk adjustment. Risk factor adjustment should be used when comparing coronary artery bypass grafting with current and future treatment innovations and when selecting the best treatment strategy for individual patients.
Acute Type B Aortic Dissection: Does Aortic Arch Involvement Affect Management and Outcomes?
Authors: Tsai Thomas T. , Isselbacher Eric M. , Trimarchi Santi , Bossone Eduardo , Pape Linda , Januzzi James L. , Evangelista Arturo , Oh Jae K. , Llovet Alfredo , Beckman Joshua , Cooper Jeanna V. , Smith Dean E. , Froehlich James B. , Fattori Rossella , Eagle Kim A , Nienaber Christoph A.
Published: September 2007

Background—

Stanford Type B acute aortic dissection (TB-AAD) spares the ascending aorta and is optimally managed with medical therapy in the absence of complications. However, the treatment of TB-AAD with aortic arch involvement (AAI) remains an unresolved issue.

Methods and Results—

We examined 498 patients with TB-AAD enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2003. Kaplan-Meier mortality curves were constructed and multivariate regression models were performed to identify independent predictors of AAI and to evaluate whether AAI was an independent predictor of follow-up mortality. We found that 371 (74.5%) patients with TB-AAD did not have AAI versus 127 (25.5%) with AAI. Independent predictors of AAI were a history of previous aortic surgery (OR 3.4; 95% CI, 1.6 to 7.6;
P
=0.002), absence of back pain (OR 1.6; 95% CI, 1.1 to 2.5;
P
=0.05), and any pulse deficit (1.9; 95% CI, 1.1 to 3.3,
P
=0.03). Mortality for patients without AAI was 9.4%±4.3% and 21.0%±6.9% at 1 and 3 years versus 9.2%±7.7% and 19.9%±11.1% with AAI, respectively (mean follow-up overall, 2.3 years, log rank
P
=0.82). AAI was not an independent predictor of long-term mortality.

Conclusions—

Patients with TB-AAD and aortic arch involvement do not differ with regards to mortality at 3 years. Whether or not AAI involvement impacts other measures of morbidity such as freedom from operation or endovascular intervention deserves further study.
Low Dose Nesiritide and the Preservation of Renal Function in Patients With Renal Dysfunction Undergoing Cardiopulmonary-Bypass Surgery
Authors: Chen Horng H. , Sundt Thoralf M. , Cook David J. , Heublein Denise M. , Burnett John C
Published: September 2007

Background—

Renal insufficiency is associated with increased morbidity and mortality after cardiopulmonary bypass cardiac surgery. B-type natriuretic peptide is a cardiac hormone that enhances glomerular filtration rate and inhibits aldosterone. Cystatin has been shown to be a better endogenous marker of renal function than creatinine.

Methods and Results—

We performed a double-blinded placebo-controlled proof of concept pilot study in patients (n=40) with renal insufficiency preoperatively (defined as an estimated creatinine clearance of <60 mL/min determined by the Cockroft-Gault formula), undergoing cardiopulmonary bypass cardiac surgery. Patients were randomized to placebo (n=20) or IV low dose nesiritide (n=20; 0.005 μg/Kg/min) for 24 hours started after the induction of anesthesia and before cardiopulmonary bypass. Patients in the nesiritide group had an increase of plasma B-type natriuretic peptide and its second messenger cGMP with a decrease in plasma cystatin levels at the end of the 24-hour infusion. These changes were not observed in the placebo group. There was a significant activation of aldosterone in the placebo group at the end of the 24-hour infusion, but not in the nesiritide group. At 48 and 72 hours, there was a decrease in estimated creatinine clearance and an increase in plasma cystatin as compared with end of the 24-hour infusion in the placebo group. In contrast, renal function was preserved in the nesiritide group with no significant change in estimated creatinine clearance and a trend for plasma cystatin to increase as compared with end of the 24-hour infusion.

Conclusion—

This proof of concept pilot study supports the conclusion that perioperative administration of low dose nesiritide is biologically active and decreases plasma cystatin in patients with renal insufficiency undergoing cardiopulmonary bypass cardiac surgery. Further studies are warranted to determine whether these physiological observations can be translated into improved clinical outcomes.
Percutaneous Mitral Valvuloplasty Versus Surgical Treatment in Mitral Stenosis With Severe Tricuspid Regurgitation
Authors: Song Hyun , Kang Duk-Hyun , Kim Jeong Hoon , Park Kyoung-Min , Song Jong-Min , Choi Kee-Joon , Hong Myeong-Ki , Chung Cheol Hyun , Song Jae-Kwan , Lee Jae-Won , Park Seong-Wook , Park Seung-Jung
Published: September 2007

Background—

The persistence of significant tricuspid regurgitation (TR) after percutaneous mitral valvuloplasty (PMV) is known to be an independent predictor of adverse outcome in mitral stenosis (MS). However, it remains unclear whether mitral valve (MV) surgery combined with surgical correction of TR is the better treatment option than PMV in patients with severe MS and severe functional TR.

Methods and Results—

We included a total of 92 consecutive patients (18 men, age 49±13 years) with severe MS and severe functional TR, who were potential candidates for PMV from 1997 to 2005, and the exclusion criteria were defined as the presence of left atrial thrombi, mitral regurgitation ≥grade 3, echo score >10, and left ventricular ejection fraction (EF) <35%. PMV was performed on 48 patients (PMV group), and MV surgery combined with tricuspid valve (TV) repair was performed on 44 patients (TVP group). The clinical events were defined as death, repeat surgical or percutaneous intervention, and readmission because of heart failure. There were no significant differences between the 2 groups in terms of gender, baseline EF, and baseline severity of pulmonary hypertension, but patients in the TVP group were older and had a higher echo score and a higher incidence of atrial fibrillation than those in the PMV group. During follow-up of 57±35 months, 2 deaths occurred in the TVP group, and there were 2 deaths, 7 cases of heart failure requiring surgical intervention in the PMV group. The difference of event rates between the 2 groups showed borderline significance (
P
=0.05), but no difference in mortality was observed. The estimated actuarial 7-year event-free survival rate was 77±8% in the PMV group and 95±3% in the TVP group. Severe TR was improved to mild or absent TR in 43 (98%) patients in the TVP group, and this was significantly higher than in the PMV group (22/48, 46%;
P
<0.001). In the TVP group, the right ventricle (RV) size was significantly decreased in 18 (90%) patients among 20 patients with preoperative significant RV enlargement. On stepwise multivariate logistic regression analysis, TVP group and baseline sinus rhythm were independent predictors for improvement of TR (
P
<0.001).

Conclusions—

TV repair combined with MV surgery was related to better clinical outcomes than PMV alone, and we recommend that this surgical option should be considered preferentially in severe MS with severe functional TR, especially if atrial fibrillation or enlarged RV is associated.
Limited Long-Term Durability of the Cryolife O’Brien Stentless Porcine Xenograft Valve
Authors: Pavoni Daisy , Badano Luigi P. , Ius Fabio , Mazzaro Enzo , Frassani Romeo , Gelsomino Sandro , Livi Ugolino
Published: September 2007

Background—

Despite the fact that early and midterm hemodynamic and clinical results of the Cryolife O’Brien (CLOB) stentless valve have been reported to be favorable, the long-term durability and clinical results of this valve are largely unknown. Accordingly, we analyzed 10-year outcomes after aortic valve replacement with this valve.

Methods and Results—

From January 1994 to September 2004, 185 patients (67, 73, and 75 years, 25th, 50th, and 75th quartiles, respectively; 38% older than 75 years; 56% females) underwent aortic valve replacement with the CLOB valve. Sixty-eight percent of patients were in NYHA class 3 to 4. Standard EuroSCORE was 7.1±2.7. Pure aortic stenosis accounted for 42% (n=79), and pure insufficiency for 12% of cases (n=22). Concomitant surgery: 28% coronary artery bypass (n=51), 11% mitral valve replacement/annuloplasty (n=21), and 2% ascending aorta replacement (n=3). Sixty-one percent of patients received a 23-mm valve or smaller size. Follow-up was 100% completed, and cumulative follow-up was 65 months/patient. The 30-day mortality was 5.4% (none were valve related). Actuarial survival at 5 and 10 years were 68% and 40%, respectively. Actuarial freedom from structural valve deterioration was 91% at 5 years and dropped to 44% at 10 years. Actuarial freedom from reoperation was 94% at 5 years and declined to 57% at 10 years.

Conclusions—

In a population with a high prevalence of elderly females with small aortic root, the CLOB valve demonstrated satisfactory clinical results till 8-years. Afterward, a significant increase in hazard for structural valve deterioration and reoperation occurred in late follow-up.
c-Kit Dysfunction Impairs Myocardial Healing After Infarction
Authors: Cimini Massimo , Fazel Shafie , Zhuo Sun , Xaymardan Munira , Fujii Hiroko , Weisel Richard D. , Li Ren-Ke
Published: September 2007

Background—

We hypothesized that c-kit receptor function in the bone marrow is important for facilitating healing, leading to efficient cardiac repair after myocardial infarction (MI).

Methods and Results—

We used

Kit
W
/Kit
W-v

c-kit mutant mice and their wild-type littermates to assess the importance of c-kit function in cardiac remodeling after coronary ligation. We found that mutant mice developed 1.6-fold greater ventricular dilation (
P
=0.008) attributable to a 1.3-fold greater infarct expansion by day 14 after MI (
P
=0.01). The number of proliferating smooth muscle α-actin expressing cells was 1.8-fold lower in mutant mice at day 3 (
P
<0.01), resulting in a 1.6 to 1.8-fold reduction in total regional nonvascular smooth muscle α-actin expressing cells by both microscopy and flow cytometry (
P
<0.001 for both). This decrease was accompanied by a 1.4-fold reduction in the number of CD31 expressing blood vessels (
P
<0.05). Prior transplantation of wild-type bone marrow cells into mutant mice rescued the efficient establishment of vessel-rich repair tissue by inducing a 1.5-fold increase in nonvascular smooth muscle α-actin expressing cells and CD31 expressing blood vessels (
P
<0.05 for both). The increased recruitment of cells into the infarct region in the chimeric mice was associated with reduced infarct expansion (
P
<0.03) compared to wild-type levels.

Conclusions—

Bone marrow c-kit function critically impacts the myofibroblast repair response in infarcted hearts. Interventions that increase the infiltration of c-kit
+
cells to the infarcted heart may potentiate this endogenous repair response, prevent infarct expansion, and improve the recovery of cardiac function after MI.