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Standard open chest Coronary Artery Bypass Grafting (CABG) has evolved over last couple of decades. With advancement in minimally invasive procedures, Robotic CABG (RCABG) is still in its evolution phase. There is dearth of experienced surgeons in this complicated field and lack of data to verify it clinical safety. in this review, we intend to describe the utility of Cardiac Computed Tomography Angiography (CCTA) in assessment of graft anatomy and quality, grafting strategy, distal graft anastomosis site evaluation and detection of complications associated with RCABG. CCTA appears to provide valuable information regarding the visualization of grafts, target coronary arteries and other cardiac and non-cardiac structures., Highlights • Surgical morbidity and mortality is improved in robotic CABG given small incisions and preserved integrity of sternum and the chest wall. • CCTA is helpful in evaluating graft anatomy, assessing graft origin and distal anastomosis and detection of complications associated with the robotic CABG. • CCTA also provides important diagnostic information regarding the native coronary arteries and other cardiac and non-cardiac structures.

Achieving hemostasis during surgery is a common challenge across surgical specialties and procedures, including cardiovascular and peripheral vascular procedures. Although several hemostatic agents are available, they all become less effective as bleeding becomes more vigorous. Veriset™ hemostatic patch is a topical hemostatic agent that has been approved for use on solid organs and in soft tissue. The primary aim of these studies was to assess the safety of Veriset hemostatic patch during cardiovascular and peripheral vascular procedures.Adult domestic swine were given intraoperative anticoagulation and systemic antiplatelet therapy, and then underwent a variety of cardiovascular coronary artery bypass graft (CABG anastomosis and aortotomy closure) and peripheral vascular (carotid arteriotomy with patch angioplasty) procedures. Bleeding was identified or created from each anastomotic site and was brisk in many cases. Veriset hemostatic patch, Surgicel(®) Nu-Knit(®) absorbable hemostat, or standard of care treatment was applied topically to the site of bleeding, and time to hemostasis was monitored for each animal. Animals were assessed during and after the surgical procedure to determine the effects of treatment on vessel diameter, clinical laboratory parameters, and host tissue response and/or tissue integration.Application of Veriset hemostatic patch had no effect on vessel diameter, similar to Surgicel Nu-Knit absorbable hemostat and standard of care treatment. Approximately 28 days after application, Veriset hemostatic patch and Surgicel Nu-Knit absorbable hemostat were completely absorbed, with no impact on serum chemistry profiles. Furthermore, Veriset hemostatic patch was as effective or more effective than Surgicel Nu-Knit absorbable hemostat when applied during carotid arteriotomy (30.0 ± 0.0 sec vs. 163.6 ± 86.9 sec, P 0.001) and CABG anastomosis (91.9 ± 66.0 sec vs. 207.5 ± 159.2 sec, P = 0.053).Veriset hemostatic patch exhibits similar safety as Surgicel Nu-Knit absorbable hemostat, with effectiveness against cardiovascular and peripheral vascular bleeding. If these preclinical results are confirmed in clinical trials, this highly effective patch with a topical application requiring less than 30 seconds is likely to prove useful in many clinical settings.

An emergent open thoracotomy (OT) is a high-risk, low-frequency procedure uniquely suited for simulation training. We developed a cost-effective Cardiothoracic (CT) Surgery trainer and assessed its potential for improving technical and interprofessional skills during an emergent simulated OT.We modified a commercially available mannequin torso with artificial tissue models to create a custom CT Surgery trainer. The trainer's feasibility for simulating emergent OT was tested using a multidisciplinary CT team in three consecutive in situ simulations. Five discretely observable milestones were identified as requisite steps in carrying out an emergent OT; namely (1) diagnosis and declaration of a code situation, (2) arrival of the code cart, (3) arrival of the thoracotomy tray, (4) initiation of the thoracotomy incision, and (5) defibrillation of a simulated heart. The time required for a team to achieve each discrete step was measured by an independent observer over the course of each OT simulation trial and compared.Over the course of the three OT simulation trials conducted in the coronary care unit, there was an average reduction of 29.5% (P0.05) in the times required to achieve the five critical milestones. The time required to complete the whole OT procedure improved by 7 min and 31 s from the initial to the final trial-an overall improvement of 40%.In our preliminary evaluation, the CT Surgery trainer appears to be useful for improving team performance during a simulated emergent bedside OT in the coronary care unit.

Neurogenic tumors do not often occur in the superior sulcus or apex of the chest cavity. Historically, surgical approaches have been dictated by the location of the tumor and its relation to the contiguous structures such as the vertebral bodies, subclavian vessels, and chest wall. Resection is hampered by difficulties with visualization and access within a narrow working space. The shortcomings associated with the traditional surgical approaches create a potential of injury to nearby structures. We present a case of a 43-year-old woman with a superior sulcus neurogenic tumor impinging on the left subclavian vein, who underwent a successful resection without injury to nearby structures. We found that a robotic approach improved visualization of the tumor and nearby structures and increased instrument maneuverability relative to a thoracoscopic approach, along with less pain and recovery time compared with a thoracotomy. This experience suggests that robotics provides a promising alternative for excision of superior sulcus neurogenic tumors, which may reduce associated morbidity.

Background A complete Cox maze IV procedure is difficult to accomplish using current endoscopic and minimally invasive techniques. These techniques are hampered by inability to adequately dissect the posterior structures of the heart and place all necessary lesions. We present a novel approach, using robotic technology, that achieves placement of all the lesions of the complete maze procedure. Methods In three cadaveric human models, the technical feasibility of using robotic instruments through the right chest to dissect the posterior structures of the heart and place all Cox maze lesions was performed. Results The entire posterior aspect of the heart was dissected in the cadaveric model facilitating successful placement of all Cox maze IV lesions with robotic assistance through minimally invasive incisions. Conclusion The robotic Cox maze IV procedure through the novel right thoracic approach is feasible. This obviates the need for sternotomy and avoids the associated morbidity of the conventional Cox-maze procedure. Copyright © 2015 John Wiley & Sons, Ltd.

Significance Heart rate monitors, pacemakers, cardioverter-defibrillators, and neural stimulators constitute broad classes of electronic implants that rely on battery power for operation. Means for harvesting power directly from natural processes of the body represent attractive alternatives for these and future types of biomedical devices. Here we demonstrate a complete, flexible, and integrated system that is capable of harvesting and storing energy from the natural contractile and relaxation motions of the heart, lung, and diaphragm at levels that meet requirements for practical applications. Systematic experimental evaluations in large animal models and quantitatively accurate computational models reveal the fundamental modes of operation and establish routes for further improvements.

Background: Current guidelines recommend that clopidogrel should be held for 5 days prior to coronary artery bypass graft (CABG) procedure. However, it is unknown if this recommendation should apply to robotic-assisted (rCABG), which is less invasive because it does not involve sternotomy and thus reduces the risk of bleeding. Objective: To compare postoperative bleeding for rCABG patients who were taking clopidogrel within 5 days of the procedure with those who were not taking clopidogrel. Methods: This was a retrospective cohort study conducted between January 1, 2012 and December 31, 2012 of consecutive patients undergoing rCABG. Patients were categorized into 2 groups based on whether or not clopidogrel was administered within 5 days prior to the date of surgery. The primary outcome measure was the occurrence of the Bleeding Academic Research Consortium (BARC) definition for CABG-related bleeding. The secondary outcome measure was a comparison of chest tube output during the first 24-hour postoperative period. Results: A total of 136 rCABG patients were included in the final analyses. Of these, 39 (29%) received clopidogrel within 5 days of surgery. CABG-related bleeding using the BARC definition occurred in 26% of patients who received clopidogrel and 8% of patients who did not ( P = .011). Median chest tube output during the first 24-hour postoperative period was also greater in patients who received clopidogrel (900 vs 735 mL, P = .002). Conclusions: The use of clopidogrel within 5 days of rCABG is associated with greater postoperative bleeding and chest tube output, as defined by the BARC criteria.

Objectives The objective of this study was to characterize the bleeding, transfusion, and other outcomes of patients related to the timing of prasugrel or clopidogrel withdrawal before coronary artery bypass grafting (CABG). Background There is little evidence to guide clinical decision making regarding the use of prasugrel in patients who may need urgent or emergency CABG. Experience with performing CABG in the presence of clopidogrel has raised concern about perioperative bleeding complications that are unresolved. Methods A subset of the TRITON–TIMI 38 study (Trial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet Inhibition with Prasugrel–Thrombolysis In Myocardial Infarction 38), in which patients with acute coronary syndrome were randomized to treatment with aspirin and either clopidogrel or prasugrel, underwent isolated CABG (N = 346). A supplemental case report form was designed and administered, and the data combined with the existing TRITON–TIMI 38 database. Baseline imbalances were corrected for using elements of the European System for Cardiac Operative Risk Evaluation and The Society of Thoracic Surgeons predictive algorithm. Results A significantly higher mean 12-h chest tube blood loss (655 ± 580 ml vs. 503 ± 378 ml; p = 0.050) was observed with prasugrel compared with clopidogrel, without significant differences in red blood cell transfusion (2.1 U vs. 1.7 U; p = 0.442) or the total donor exposure (4.4 U vs. 3.0 U; p = 0.463). All-cause mortality was significantly reduced with prasugrel (2.31%) compared with 8.67% with clopidogrel (adjusted odds ratio: 0.26; p = 0.025). Conclusions Despite an increase in observed bleeding, platelet transfusion, and surgical re-exploration for bleeding, prasugrel was associated with a lower rate of death after CABG compared with clopidogrel. (A Comparison of Prasugrel [CS-747] and Clopidogrel in Acute Coronary Syndrome Subjects Who Are to Undergo Percutaneous Coronary Intervention; NCT00097591 )

Purpose of review Endoscopic vein harvest (EVH) has quickly been adopted as the standard-of-care for coronary artery bypass grafting (CABG). Despite clear advantages in terms of wound morbidity, healing, pain, and patient satisfaction, data from recent large clinical trials have called the safety of this technique into question. Recent findings Post-hoc analyses of a variety of prospective trials have suggested EVH is associated with decreased graft patency, higher rates of cardiovascular complications (e.g. myocardial infarction, need for repeat revascularization) and mortality. Imaging studies of veins procured by EVH have revealed retained clot and vascular injury, particularly during the 'learning curve' of the technician. These findings may alter the quality of the conduit and, therefore, the outcome of the bypass graft. Elucidating the mechanisms that underlie any differences in results produced by the open and endoscopic procedures would help better inform clinical practice and the development of targeted strategies to improve EVH. Summary Clear clinical advantages over traditional open vein harvest have allowed EVH to rapidly become the standard-of-care for harvesting of one or more vein grafts during CABG. The quality of these conduits, suggested to be equivalent by early studies, has come into question as groups with varying levels of experience have adopted the endoscopic technique. Elucidating the principles of 'best practice' for vein harvest will likely help shorten the learning curve and improve the safety of EVH.

Recent studies have suggested that endoscopic vein harvest (EVH) compromises graft patency. To test whether the learning curve for EVH alters conduit integrity owing to increased trauma compared with an open harvest, we analyzed the quality and early patency of conduits procured by technicians with varying EVH experience.During coronary artery bypass grafting, veins were harvested open (n=10) or by EVH (n=85) performed by experienced (900 cases,30/month) versus novice100 cases,3/month) technicians. Harvested conduits were imaged intraoperatively using optical coherence tomography and on day 5 to assess graft patency using computed tomographic angiography.Conduits from experienced (n=55) versus novice (n=30) harvesters had similar lengths (33 versus 34 cm) and harvest times (32.4 versus 31.8 minutes). Conduit injury was noted in both EVH groups with similar distribution among disruption of the adventitia (62%), intimal tears at branch points (23%), and intimal or medial dissections (15%), but the incidence of these injuries was less with experienced harvesters and rare in veins procured with an open technique. Overall, the rate of graft attrition was similar between the two EVH groups (6.45% versus 4.34% of grafts; p=0.552). However, vein grafts with at least 4 intimal or medial dissections showed significantly worse patency (67% versus 96% patency; p=0.05).High-resolution imaging confirmed that technicians inexperienced with EVH are more likely to cause intimal and deep vessel injury to the saphenous vein graft, which increases graft failure risk. Endoscopic vein harvest remains the most common technique for conduit harvest, making efforts to better monitor the learning curve an important public health issue.

To the Editor: Lopes and colleagues (July 16 issue) 1 report data on vein-graft harvesting techniques from the Project of Ex-vivo Vein Graft Engineering via Transfection IV (PREVENT IV) study and conclude that endoscopic vein-graft harvesting, as compared with open harvesting, is independently associated with increased vein-graft failure and adverse outcomes. In another analysis from the same study, 2 offpump and on-pump coronary-artery bypass grafting (CABG) were compared. An interesting finding was that with endoscopically harvested grafts, the probability of graft failure was significantly higher in the off-pump group than in the on-pump group (odds ratio, 1.78 vs. 1.27). In addition, vein grafts of poor or fair quality (as compared with those of good quality) had a significantly higher rate of failure with off-pump than with on-pump CABG. The failure rate of left internal thoracic artery grafts was about 8%, as compared with a failure rate of about 25% for vein grafts. The failure rate of grafts to the left anterior descending artery was much lower than that of grafts to the right coronary artery and circumflex arteries. The study by Lopes et al. does not adjust for the use of off-pump CABG or of left internal thoracic artery grafts. Furthermore, there is no information on the quality of the veins or of the target vessels. These are major omissions that may have an effect on the results and conclusions of the study.

Thrombin is the central enzymatic mediator of both hemostasis and thrombosis. Thrombin produced in a controlled fashion creates fibrin polymers critical for hemostasis while a larger burst activates platelets via its high affinity thrombin receptor, protease-activated receptor-1 (PAR-1), leading to a platelet-rich clot and thrombosis.1 Blood collected from standardized bleeding time skin incision on the forearm provides a model of hemostasis in response to microvascular injury.2,3 Because surgically grafted vessels always develop some degree of perioperative endothelial disruption,4 they provide a “model” of macrovascular injury. Blood sampled from the coronary sinus (CS) downstream of these grafts provides a unique opportunity to assay the regional thrombotic response to this injury.5 We have documented a significant increase in regional thrombin production downstream of saphenous vein grafts (SVGs) after off-pump as compared with on-pump coronary artery bypass graft (CABG),6 with the level of thrombin produced directly related to the risk of early SVG failure.5 This heightened regional thrombin production is particularly noteworthy in light of recent meta-analyses demonstrating that the risk of early SVG failure is increased after off-pump coronary artery bypass (OPCAB) grafting.7,8 PAR-1 receptor antagonists have demonstrated the ability to target the cellular actions of thrombin on platelets while leaving the hemostatic actions of thrombin in the coagulation cascade untouched.9 The hemostatic agent, aprotinin, has been shown to be an antagonist of PAR-1 at pharmacologically relevant doses.10,11 This inhibitory effect would be predicted to provide clinical antithrombotic actions on platelets within the macrovasculature without hindering hemostatic plug formation in the microvasculature at wound sites where alternate platelet agonists (e.g., collagen and adenosine diphosphate [ADP]) are generated.12 On the other hand, aprotinin also inhibits fibrinolysis, which raises the concern that it might increase the risk of thrombosis. Although the link between aprotinin and thrombosis has endured “twenty-five years of claim and counterclaim,”13 there have been essentially no clinical studies on the mechanism of how aprotinin may cause thrombosis. The purpose of the study was to test the hypothesis that aprotinin administration would inhibit the pathologic burst in thrombin production produced within grafted macrovessels but not physiologic thrombin required for wound hemostasis.

Long-term success in ventricular assist device (VAD) recipients is limited by thromboembolic events, the prediction of which remains elusive. We evaluated the predictive value of aspirin hyporesponsiveness and markers of coagulation and fibrinolysis.We prospectively enrolled patients scheduled to undergo VAD implantation between June 2004 and March 2006. Once before surgery, daily during hospitalization, and weekly after discharge we assessed platelet function, measured prothrombin activation fragment 1.2 (F1.2) and plasminogen activator inhibitor-1 (PAI-1) concentrations, and evaluated aspirin hyporesponsiveness by whole-blood aggregometry and thromboelastography. All patients received 325 mg oral aspirin daily from at least 7 days before VAD implantation. Follow-up continued until heart transplantation, death or closure of the database.We included 26 patients (median follow-up 315 days, range 9-833 days). In eight (31%) patients, 14 thromboembolic events occurred at a median of 42 (interquartile range 26-131) days. Only six (43%) events based on whole-blood aggregometry and one (7%) based on thromboelastography coincided with aspirin hyporesponsiveness. Within-patient variability was high for both tests (59% and 567%, respectively). Compared with levels before surgery, PAI-1 concentrations were raised for up to 45 days (P0.0001) and those of F1.2 for up to 3 days (P = 0.0001) after VAD implantation. PAI-1 and F1.2 levels did not rise significantly further before thromboembolic events.Aspirin hyporesponsiveness was not associated with raised risk of future clinical thromboembolic events after VAD implantation. Impaired fibrinolysis, demonstrated by raised PAI-1 concentrations, might, however, indicate a predisposition to such events early after surgery.

Objective Vasospasm is the primary obstacle to widespread adoption of the radial artery as a conduit in coronary artery bypass grafting. We used optical coherence tomography, a catheter-based intravascular imaging modality, to measure the degree of radial artery spasm induced by means of harvest with electrocautery or a harmonic scalpel in patients undergoing coronary artery bypass grafting. Methods Radial arteries were harvested from 44 consecutive patients with a harmonic scalpel (n = 15) or electrocautery (n = 29). Vessels were imaged before harvesting and after removal from the arm, with saphenous vein tracts serving as internal controls. Optical coherence tomographic findings for the degree of harvesting-induced injury were validated against histologic measures. Results Optical coherence tomographic measures of endovascular dimensions and injury correlated strongly with histologic findings. Mean luminal volume, a measure of vasospasm, decreased significantly less after harvesting with a harmonic scalpel (9% ± 7%) than with electrocautery (35% ± 6%, P = .015). Completely intact intima was present in 11 (73%) of 15 radial arteries harvested with a harmonic scalpel (73%) compared with 9 of 29 arteries harvested by means of electrocautery (31%, P = .011). Intraoperative flow measurements and patency rates at 5 days postoperatively were not significantly different among groups. Conclusions Optical coherence tomography provides a level of speed and accuracy for quantifying endothelial injury and vasospasm that has not been described for any other modality, suggesting potential as an intraoperative quality assurance tool. Our optical coherence tomographic findings suggest that the harmonic scalpel induces less spasm and intimal injury compared with electrocautery.

Cardiac transplantation remains the first choice for the surgical treatment of end stage heart failure. An inadequate supply of donor grafts that meet existing criteria has limited the application of this therapy to suitable candidates and increased interest in extended criteria donors. Although cold storage (CS) is a time-tested method for the preservation of hearts during the ex vivo transport interval, its disadvantages are highlighted in hearts from the extended criteria donor. In contrast, transport of high-risk hearts using hypothermic machine perfusion (MP) provides continuous support of aerobic metabolism and ongoing washout of metabolic byproducts. Perhaps more importantly, monitoring the organ's response to this intervention provides insight into the viability of a heart initially deemed as extended criteria. Obviously, ex vivo MP introduces challenges, such as ensuring homogeneous tissue perfusion and avoiding myocardial edema. Though numerous groups have experimented with this technology, the best perfusate and perfusion parameters needed to achieve optimal results remain unclear. In the present review, we outline the benefits of ex vivo MP with particular attention to how the challenges can be addressed in order to achieve the most consistent results in a large animal model of the ideal heart donor. We provide evidence that MP can be used to resuscitate and evaluate hearts from animal and human extended criteria donors, including the non-heart beating donor, which we feel is the most compelling argument for why this technology is likely to impact the donor pool.

Surgical and percutaneous coronary artery intervention revascularization are traditionally considered isolated options. A simultaneous hybrid approach may allow an opportunity to match the best strategy for a particular anatomic lesion. Concerns regarding safety and feasibility of such an approach exist. We examined the safety, feasibility, and early outcomes of a simultaneous hybrid revascularization strategy (minimally invasive direct coronary bypass grafting of the left anterior descending [LAD] artery and drug-eluting stent [DES] to non-LAD lesions) in 13 patients with multivessel coronary artery disease that underwent left internal mammary artery to LAD minimally invasive direct coronary bypass performed through a lateral thoracotomy, followed by stenting of non-LAD lesions, in a fluoroscopy-equipped operating room. Assessment of coagulation parameters was also undertaken. Inhospital and postdischarge outcomes of these patients were compared to a group of 26 propensity score matched parallel controls that underwent standard off-pump coronary artery bypass. Baseline characteristics were similar in both groups. All hybrid patients were successfully treated with DES and no inhospital mortality occurred in either group. Hybrid patients had a shorter length of stay (3.6 +/- 1.5 vs 6.3 +/- 2.3 days, P.0001) and intubation times (0.5 +/- 1.3 vs 11.7 +/- 9.6 hours, P.02). Despite aggressive anticoagulation and confirmed platelet inhibition, hybrid patients had less blood loss (581 +/- 402 vs 1242 +/- 941 mL, P.05) and decreased transfusions (0.33 +/- 0.49 vs 1.47 +/- 1.53 U, P.01). Six-month angiographic vessel patency and major adverse cardiac events were similar in the hybrid and off-pump coronary artery bypass groups. A simultaneous hybrid approach consisting of minimally invasive coronary artery bypass grafting with left internal mammary artery to LAD combined with revascularization of the remaining coronary targets using percutaneous coronary artery intervention with DES is a feasible option accomplished with acceptable clinical outcomes without increased bleeding risk.

Objective: Accumulating evidence suggests that a hypercoagulable state influences early graft failure after off-pump coronary artery bypass (OPCAB). We hypothesized that regional myocardial ischemia caused by obligatory periods of coronary occlusion during OPCAB is an important trigger for this prothrombotic state. Methods: Using a series of biomarkers, 60 consecutive patients undergoing OPCAB were monitored for myocardial injury (myoglobin), inflammation (TNF-a, IL-8) and thrombosis (thrombin generation-F1.2, contact activation pathway-FXII-a, platelet derived microparticles-via flow cytometry). The transcardiac gradients of these markers were determined by assaying both arterial and coronary sinus blood just after protamine administration. Intramyocardial pH was monitored continuously during coronary occlusion in a subset (N = 30 grafts, 11 patients). The influence of management strategies affecting hemostasis (e.g. antiplatelet therapy, anti-fibrinolytics, peak activated clotting time (ACT) during heparinization) was analyzed. Results: Ischemic injury, depicted by the transcardiac myoglobin gradient, significantlycorrelatedwithintramyocardialacidosisduringcoronaryocclusion(R = 0.96,p < 0.0001)andpredictedthetranscardiacgradientsof TNF-a (R = 0.83, p < 0.001) and F1.2 (R = 0.72, p < 0.0001). Transcardiac F1.2 strongly correlated with TNF-a (R = 0.73, p = 0.01) and IL-8 (R = 0.51, p = 0.02). Patients receiving aprotinin (N = 20) showed significantly lower transcardiac gradients for myoglobin (4.1 7.5% vs 72.9 108.8% change, p = 0.002), F1.2 (31 37% vs 89 149%, p = 0.03), FXII-a (2.6 4.1% vs 19.2 34%, p = 0.04) and microparticles (7 3.9% vs 12.9 8%, p = 0.01). Conclusions: Strong correlations between myocardial ischemia and the transcardiac gradients of markers for inflammation and thrombosis suggest that even brief episodes of coronary occlusion in the beating heart may have pathophysiologic consequences. Aprotinin, but not other factors that influence the coagulation system, appears to mitigate this process during OPCAB.

Objective. Saphenous vein grafts (SVG) used for coronary artery bypass surgery (CABG) often develop a gradual luminal narrowing over the first year due to neointimal hyperplasia (NH). Although the basic science of NH is well studied, our clinical understanding of this issue is limited. The purpose of this cohort study was to investigate clinical risk factors for NH by monitoring luminal narrowing within SVG using multichannel CT angiography (CTA). Methods. Thirty patients underwent CABG involving SVG (N = 44) and arterial grafts (N = 36). Patient variables were recorded and the baseline quality of each conduit determined intraoperatively by analyzing surplus segments for intima-media thickness ratio (IMT) by histology and matrix metalloproteinase-2 by enzyme-linked immunosorbent assay. Percent luminal narrowing (%LN) was calculated for each patent graft by comparing the CTA appearance on day 5 to a repeat study at 1 y. Results. Compared with arterial grafts, SVG showed significantly higher IMT at baseline (0.9 ± 0.65 versus 0.22 ± 0.17, P < 0.0001) and more %LN over the first year (6.9 ± 7.5 versus 25.3 ± 13.3% LN, P< 0.0001). Of all of the measured variables, the only significant predictors of %LN included baseline IMT (r = 0.58, P = 0.002) and matrix metalloproteinase-2 levels (r = 0.60, P = 0.002) in SVG. Conclusions. The degree of NH at baseline, a phenomenon exclusive to SVG and not found in arterial grafts, was significantly related to the development of lumen loss in the conduit over the first year after CABG. The study of SVG using serial CTA may provide unique insights into the natural history of SVG remodeling and to identify factors that influence the long-term function of this conduit.

Objective Early benefits from transmyocardial laser revascularization (TMR) may be related to acute sympathetic denervation. This study hypothesized that TMR as an adjunct to off-pump coronary artery bypass (OPCAB) would improve myocardial runoff in the TMR-treated regions and increase graft flow. Methods Graft blood flow was measured in 145 consecutive OPCAB patients. In patients with graft flow Results Risk factors, comorbidities, and preoperative medications were similar in all groups. TMR led to a 48% increase in bypass graft flow in 12 patients, but no significant change in flow in the remainder (n = 13). The control group also showed no change in graft flow measured during the same time-points. Compared with those that did not respond to TMR, responders showed a greater drop in pH during warm ischemia caused by distal anastomoses during OPCAB and significantly higher transcardiac gradients of F1.2, IL-8, TNFα, and VCAM. Conclusions TMR acutely improves venous bypass graft flow in regions with more severe myocardial acidosis and inflammation during and after OPCAB. Acute sympathetic denervation after TMR may provide mechanistic insight into the early clinical benefits of TMR as an adjunct to OPCAB.

Prothrombin time, expressed as international normalized ratio (INR) and activated partial thromboplastin time (aPTT), are standard methods of monitoring coumadin and heparin administration. Prothrombin activation fragment (F1.2) is an index of in vivo thrombin generation. We hypothesized that F1.2 would provide a better surrogate of thromboembolism risk than standard coagulation assays during ventricular assist device (VAD) support. INR, PTT and F1.2 were analyzed in 31 patients after implantation of a left-sided VAD daily during hospitalization and weekly after discharge. Thromboembolic events (TE) were defined by evidence of neurological injury revealed by plasma levels of S-100beta. The relationships between F1.2, INR for patients on coumadin and aPTT for patients on heparin were evaluated from 1250 observations of blood samples. S-100beta was positively correlated with F1.2, but not with INR and aPTT. Correlation between S-100beta and F1.2 is significantly higher than with the other two markers (P

Objectives Endothelial disruption within saphenous vein and radial artery grafts increases thrombosis risk. However, no clinically applicable method for imaging the intima currently exists. We used a novel infrared imaging technology, optical coherence tomography (OCT; LightLab Imaging, Inc, Westford, Mass), to visualize the intima within harvested conduits. Methods Conduits were procured endoscopically (37 saphenous vein grafts and 8 radial artery grafts) or with the open technique (9 radial artery grafts) from 50 patients. Surplus segments were analyzed by means of OCT for evidence of preexisting pathology or traumatic injury. Focal plaques in radial artery grafts and the intimal hyperplasia area in saphenous vein grafts were quantified as having an intimal/medial thickness ratio of greater than 0.5. Biopsy specimens were obtained for histologic confirmation and to analyze matrix metalloproteinase 2 levels (saphenous vein grafts) and prostacyclin/nitric oxide metabolites (radial artery grafts). Interobserver κ coefficients and a Bland–Altman analysis were used to determine the reproducibility and accuracy of OCT interpretations. Results Radial artery imaging revealed plaque in 76%. Endoscopically harvested vessels showed intraluminal clot (38%) and intimal tears ranging from severe (6%) to mild (88%). In saphenous vein grafts intimal thickening was detected in 86% and intraluminal clotting in 68%. The intimal/medial thickness ratio determined by means of OCT correlated directly with matrix metalloproteinase 2 levels ( R = 0.6804) in saphenous vein grafts and inversely with metabolites of prostacyclin ( R = −0.55) and nitric oxide ( R = −0.58) in radial artery grafts. OCT imaging was reproducible (interobserver κ coefficients of >0.81 for the characterization of plaque types) and showed a strong correlation with histology ( R = 0.8, P Conclusions OCT imaging provides an accurate, real-time, and reproducible means for assessing saphenous vein graft and radial artery graft bypass conduits. As a quality assurance tool, this technology might afford a more objective basis for conduit selection.

Left ventricular assist devices (LVADs) are commonly used as either a bridge-to-transplant or a destination therapy. The traditional approach for LVAD implantation is via median sternotomy, but many candidates for this procedure have a history of failed cardiac surgeries and previous sternotomy. Redo sternotomy increases the risk of heart surgery, particularly in the setting of advanced heart failure. Robotics facilitates a less invasive approach to LVAD implantation that circumvents some of the morbidity associated with a redo sternotomy. We compared the outcomes of all patients at our institution who underwent LVAD implantation via either a traditional sternotomy or using robotic assistance. The robotic cohort showed reduced resource utilization including length of hospital stay and use of blood products. As the appropriate candidates become elucidated, robotic assistance may improve the safety and cost-effectiveness of reoperative LVAD surgery.

Hybrid coronary revascularization (HCR) combines a surgical and percutaneous approach for treatment of multivessel coronary artery disease. A survey was conducted among 200 cardiologists and cardiac surgeons from 100 top-ranked US hospitals. Questions were asked involving the perception, experience, and future expectations of HCR. Of physicians invited to the survey, 90 completed the survey (45.5%). Relative to nonresponders, responders were more often affiliated with an academic institution (80.0% vs 61.8%, P=.005), with higher patient volumes, and with the availability of a hybrid operating room (90.0% vs 67.3%, P

Coronary artery bypass grafting is one of the most thoroughly investigated and stereotyped procedures to date. The vast cumulative experience of CABG to date has resulted in both a highly streamlined and optimized commodity while also creating a barrier against innovation. As such, the mainstay approach to CABG is fundamentally the same as it was 20 years ago. However, more recently, a number of less invasive approaches have presented themselves that may begin to change the current surgical landscape. Robotic assistance now enables surgeons to perform CABG in a minimally invasive fashion either via minimally invasive direct CABG (MIDCAB) or totally endoscopically (TECAB). These approaches offer distinct advantages including attenuation of bleeding and infection risk, reduced postoperative recovery time and convalescence, as well as shorter hospital stays. Likewise they allow healthcare systems to meet the growing market demand for less invasive revascularization, thereby increasing market share, while becoming part of a modern strategy for achieving patient-centered care. However, implementing these novel procedures is not without difficulty. Less invasive approaches are associated with a significant learning curve that creates a challenging training environment during critical early adoption phases of this approach. Furthermore, some have raised concerns over the safety and cost of these technically complex operations. While much remains to be learned, there is a growing body of data to suggest that these procedures are both safe and cost effective in expert hands. Despite this, perceptions of these early experiences are difficult to change and remain a persistent hindrance to more widespread adoption. Changing these perceptions requires a combined approach of establishing consensus of the appropriate metrics of success while generating support among a broad base of stakeholders.

Objective Strands of clot are frequently flushed out of saphenous vein grafts (SVG) during preparation for grafting, particularly those that are endoscopically harvested. However, saline distention at uncontrolled pressures increases graft thrombogenicity and the risk of early failure after coronary artery bypass grafting. The purpose of this prospective investigation was to define the incidence of intraluminal clot within endoscopically harvested SVG and the effect of attempted removal by saline distention. Methods Endoscopically harvested SVG were intraoperatively prepared for grafting by using saline distention at uncontrolled pressure (n = 24) or without distension (n = 20). Optical coherence tomography, a catheter-based infrared imaging system, was used to identify and characterize intraluminal clot strands in surplus SVG segments (average length for analysis, 4.9 ± 2.6 cm). These segments were also assessed for luminal tissue factor activity and percent endothelial integrity by CD31-directed immunohistochemistry. Results Clot strands were observed in 45.4% (20 of 44) of imaged SVG segments (severity of observed clots: 54%, mild; 32%, moderate; 14%, severe). Compared with grafts distended with saline, vein segments that were not distended displayed significantly higher endothelial integrity (60.1% ± 27.2% versus 24.7% ± 24.1%, P < 0.05) and lower tissue factor activity (1.28 ± 0.95 versus12.3 ±5.5 U/cm2, P < 0.001) despite having a higher incidence of clot stands (65.0% versus 29.1%, P < 0.02, Fisher exact test). Static flow was observed in veins during endoscopic harvest. Conclusions Clot strands of varying severity are a common finding after endoscopic vein harvest. Saline distention is not completely effective in removing clot strands and increases overall graft thrombogenicity. Therefore, prevention of clot or less traumatic methods of removing clot are indicated.

Background Interest in percutaneous therapy of heart valve disease has focused attention on the high-risk patient with aortic stenosis. Aortic valve bypass (apicoaortic conduit) surgery is the construction of a vascular graft containing a bioprosthetic valve from the apex of the left ventricle to the descending thoracic aorta. We have undertaken a programmatic effort to perform aortic valve bypass surgery as an alternative to conventional aortic valve replacement in selected high-risk patients, and now report our recent experience. Methods Between April 2003 and May 2005, 14 patients with aortic stenosis underwent aortic valve bypass surgery at two institutions. All patients selected for aortic valve bypass surgery were deemed to be at very high risk for conventional aortic valve replacement. These patients represented 14 (5.8%) of all 243 patients undergoing isolated aortic valve surgery during the same time period. Mean Society of Thoracic Surgeons predicted risk for operative mortality (11%) was between the 90th and 95th percentile. Results Twelve of 14 patients had previous cardiac surgery with patent bypass grafts. Average age was 78 years. Mean aortic valve area was 0.68 cm 2 . All operations were performed through a left thoracotomy on the beating heart (cross-clamp time, 0 minutes). Cardiopulmonary bypass was used for 6 patients (median cardiopulmonary bypass time, 15 minutes). There were 2 perioperative deaths. Median postoperative length of stay was 9 days. Two noncardiac late deaths occurred. Nine of 10 surviving patients are functional class I and are living independently. Early postoperative echocardiography confirms excellent aortic valve bypass function with preservation of ventricular ejection performance. Conclusions Treatment of high-risk aortic stenosis patients with aortic valve bypass surgery is promising. Avoidance of sternotomy and cardiopulmonary bypass supports broader application to moderate-risk patients with aortic stenosis and as a control arm for studies of novel interventional therapies.

ObjectiveThe predominant mechanism of early graft failure after coronary artery bypass grafting remains in doubt. Aspirin administered in the initial hours after coronary artery bypass grafting improves graft patency, implicating prostanoid synthesis in the pathogenesis. We hypothesized that synergy between endothelial disruption in the venous conduit and aspirin resistance would cause vein graft failure.MethodsAspirin resistance, defined by diagnostic findings on at least two of three separate assays, was serially assessed in 225 patients undergoing off-pump coronary artery bypass grafting. Endothelial cell integrity was determined in surplus segments obtained from 408 vein grafts. The deposition of intraluminal thrombin within the vein was determined by comparing serum F1.2 levels between the coronary sinus and the aorta after grafting. Intraoperative blood flow in the grafts was measured with transit-time technology, and patency was assessed with electrocardiographically gated multichannel computed tomographic coronary angiography on day 5. Aspirin was the sole antithrombotic agent used during the study.ResultsThrombosed grafts (16/408) showed more endothelial cell loss at the time of grafting than did those grafts that remained patent (10.8% ± 21.5% vs 51.4% ± 39.1% integrity, P < .01). Aspirin resistance occurred in 67 patients (30%). Graft thrombosis was associated with aspirin resistance (P < .04) and reduced endothelial integrity (P < .01). These factors coexisted in 14 of 16 grafts that failed and were associated with elevated coronary sinus F1.2 levels.ConclusionAspirin resistance and relatively compromised venous endothelial cell integrity together marked patients whose vein grafts failed within days after off-pump coronary artery bypass grafting. These observations form a basis for identifying patients at risk and developing approaches to prevent vein injury or to selectively intervene in high-risk circumstances.

Background The Cox Maze III operation remains the gold standard for the surgical treatment of atrial fibrillation (AF). We report our experience using a flexible argon-powered metal cryoprobe for creation of the complete Cox-Maze III lesion set in patients with AF (the CryoMaze operation). Methods Beginning July 2002, 38 patients underwent the CryoMaze operation. Two patients had isolated CryoMaze procedures, whereas 36 patients had the CryoMaze performed in combination with coronary, valvular, or aortic surgery. All patients had electrocardiographic follow-up. Atrial fibrillation was continuous in 79%. Mean duration of AF before operation was 48 months. Results There were no complications related to the use of cryoenergy. There was 1 hospital death (2.6%) and no late deaths. At a mean follow-up of 12 months, 35 of 37 patients (95%) were in normal sinus rhythm. One patient required pacemaker implantation 3 months after surgery, and 1 patient refused follow-up. There have been no early or late thromboembolic events. Conclusions The CryoMaze operation reliably cures atrial fibrillation at medium term follow-up, with rates identical to those reported for the classic Cox-Maze III operation.

Background Tricuspid valve replacement (TVR) is a rarely needed operation. Choices between mechanical and biological prosthesis still generate controversy. We present our initial clinical experience with a stentless aortic root placed inverted in the tricuspid annulus. Methods Between August 2000 and September 2003, TVR for severe tricuspid insufficiency was performed in 8 patients. Indications were infective endocarditis (7) and iatrogenic damage (1). Mean age was 42.2 years old (20 to 58 years old). Five patients were male and 3 patients had a concomitant procedure (mitral valvuloplasty, coronary bypass grafting, and aortic valve replacement). A stentless aortic root, size 27 mm (n = 5) or 29 mm (n = 3) was placed inverted in the tricuspid position after the valsalva sinuses were scalloped. Interrupted 4-0 polypropylene sutures were used between the tricuspid valve annulus and the sewing ring. The struts equivalent on the stentless valve were anchored to the septal, anterior and posteroinferior wall of the right ventricle using 5-0 PTFE pledgeted sutures. Results Hospital survival was 100% and mean hospital stay was 12.5 days (3 to 18 days). Intraoperative and follow-up echocardiograms revealed no stenosis or insufficiency. Mean follow-up was 17.2 months (1–38 months). There were 3 late deaths due to continued IV drug use (n = 2) and end-stage renal failure (n = 1). Conclusions This is a novel surgical alternative for a very high risk population. Potential advantages over current options include minimization of blood contact with nonbiological surfaces, preservation of annular motion, freedom from anticoagulation, and a theoretical lower rate of calcification.

Coronary artery bypass graft (CABG) surgery is the standard of care in the treatment of advanced coronary artery disease. It is well known that the long-term clinical outcome after myocardial revascularization depends on the patency of the bypass grafts. In the past, invasive coronary angiography was used to assess the status of the grafts and check for graft occlusion. Recently, computed tomography (CT), particularly multidetector CT with electrocardiographic gating, has emerged as an important diagnostic tool for evaluation of CABGs in both the early (or =1 month) and late (1 month) postoperative settings. A variety of postoperative complications may manifest as dyspnea and chest pain, thereby mimicking recurrent angina secondary to graft occlusion. Owing to its improved spatial resolution compared with that of earlier-generation CT scanners and its ability to produce three-dimensional and multiplanar images, multidetector CT has assumed an integral role in characterization of graft patency while allowing investigation of alternative postoperative complications. In addition, the expanded capabilities of volumetric imaging may provide valuable information in preoperative planning for repeat CABG surgery.

Background Saphenous vein graft failure after coronary artery bypass surgery may be as high as 5% to 10% in the first postoperative week. We hypothesized that identifying damage sustained by saphenous vein endothelium before grafting predicts early graft attrition after off-pump coronary artery bypass graft surgery. Methods Intraoperative graft flow, platelet function, and endothelial integrity were analyzed in 125 patients undergoing off-pump coronary artery bypass graft surgery. Endothelial integrity was assessed in an excess vein segment from each graft using immunohistochemistry (CD31 staining). Platelet function was monitored just before and immediately after revascularization and on postoperative days 1 and 3 using whole blood aggregometry, thrombelastography, and platelet activated clotting time. Platelet activation was monitored using flow cytometry. Intraoperative conduit blood flow, measured by transit time ultrasonography, was used to detect and rectify anastomotic problems. Early graft patency was determined on postoperative day 5 using gated multichannel computed tomography angiography. Results In 106 patients undergoing postoperative computed tomography evaluation, 10 vein grafts in 10 patients were discovered to have developed early thrombosis, representing 4% (10 of 217) of all vein grafts. Endothelial integrity was 10.75% ± 17.56% in 10 grafts that failed early compared with 51.45% ± 36.29% in patent grafts ( p = 0.04). Perioperative platelet function and graft flow did not differ significantly between the two groups. Conclusions Although endothelial disruption predicts early failure of bypass grafts, the importance of a hypercoaguable state and low graft flow as a cause of early graft thrombosis after off-pump coronary artery bypass graft surgery was not supported by our preliminary results. A means to assess, prevent, and treat intraoperative vein graft damage will likely improve early graft patency.

Background By minimizing tissue ischemia, continuous perfusion (CP) during organ transport may increase the safety of "marginal donors." My colleagues and I investigated whether an analysis of donor heart viability predicts recovery of grafts challenged with a 24-hour preservation interval. Methods Dog hearts underwent cold static storage (CS) for 8 hours (n = 8) or 24 hours (n = 2) or CP for 24 hours with cold asanguinous, oxygenated solution (n = 8). Myocardial systolic and diastolic function and oxygen and lactate consumption were assessed at base line, during CP, and after Langendorff blood reperfusion. Base line endothelial function was evaluated by the percentage transcoronary change ([coronary sinus − aorta]/aorta) in myeloperoxidase and by platelet function and coronary flow reserve after 20 seconds of coronary artery occlusion. During CP, the endothelium was assessed by transcoronary protein release and coronary resistance. Edema was assessed by weight gain and histology. Results Base line systolic and metabolic functions showed no relation to post-Langendorff function. Compared with CS, CP resulted in a greater recovery in systolic function (87% ± 35% vs 65% ± 15% of baseline; p = 0.05) and a shorter interval required for lactate consumption to exceed production (7.0 ± 6.8 minutes vs 15.0 ± 8.9 minutes; p = 0.06). Endothelial function was heterogeneous: coronary flow reserve, 2.7 ± 0.7; percentage change in myeloperoxidase, −8.4% ± 6.8%; and change in platelet function, 4.3% ± 3.5%, as determined by thromboelastography angle at base line. Protein release during CP for 24 hours was 8.3 ± 7.1 g. Two factors predicted more than 75% systolic pressure generation recovery: use of CP and normal endothelial function ( p = 0.05; Fisher's exact test). However, CP led to edema according to histology, weight gain (72 ± 29 g), and impaired diastolic function versus CS (end-diastolic pressure-volume relationship, 1.4 ± 0.4 mm Hg/mL vs 0.8 ± 0.3 mm Hg/mL; p = 0.08). Conclusions Better systolic function despite 16 hours' more preservation than cold storage corroborates the idea that CP supports aerobic metabolism at physiologically important levels. Viability analysis focused on endothelial function and identified organs that were able to tolerate this 24-hour preservation interval.

Although the number of available donor hearts severely limits the epidemiologic impact of heart transplantation on patients with heart failure, patients with end-stage heart failure unresponsive to medical management currently have no other viable alternatives. Destination therapy with a ventricular assist device is the closest toward approaching clinical reality but has been plagued with problems of infection and stroke. The purpose of this review is to summarize recent developments in the field that may broaden the clinical impact of heart transplantation. For example, novel methods of cardiac preservation are being designed to safely evaluate and utilize “extended criteria” donors. Surgical techniques and medical management have reduced the incidence of postoperative right heart failure, and immunosuppressive regimens promise to limit chronic graft vascular disease.

Introduction. Leukocyte function-associated antigen-1 (LFA-1, CD11a) monoclonal antibody (mAb) affects many leukocyte functions without cell depletion. We hypothesized that the use of a humanized, anti-rhesus modified LFA-1 mAb (H2C12) in rhesus monkeys would cause: (1) prolonged heart allograft survival, (2) inhibition of primary but not secondary antibody responses, and (3) minimal drug toxicity. Methods and Results. Control (n=5) and H2C12-treated (n=7) (8-20 mg/kg i.v. on day -1 followed by 10 mg/kg/day) adult male rhesus recipients were inoculated with GP120 protein antigen on day -28 and -1 and grafted with heterotopic abdominal hearts (day 0). Donor-recipient pairs were equally MLR mismatched (4329.8±1124.1 CPM controls vs. 7289.0±1926.5 treated, P=NS). Mean heart allograft survival as evaluated by daily abdominal palpation was significantly prolonged in high dose recipients (23.0±2.6, n=4) vesus controls (8.2±1.3, n=5, P 35 days. Conclusions. The use of this mAb to block CD11a had the benefit of being a well tolerated, highly targeted therapy. These are the first results showing that monotherapy with anti-leukocyte function-associated antigen-1 mAb prolonged survival of MLR mismatched allogenic cardiac grafts in primates.

Background.Our purpose was to optimize hyperbaric pressure as a vector for ex vivo transfection of antisense oligodeoxynucleotides (AS-ODN) to intercellular adhesion molecule-1 to limit reperfusion injury (RI) in cardiac allografts.We investigated the effects of increased pressure, incubation time

The purpose of this review is to outline the most common objections about robotic coronary artery bypass graft (CABG), often expressed by cardiac surgeons, cardiologists, and administrators who have little direct knowledge of the procedure. The summarized objections include the high intraoperative costs of robotic versus traditional CABG, a prolonged and difficult learning curve for members of the surgical team, and concerns about compromising graft patency with this technique. Arguments for continued procedure development in robotically assisted CABG are provided.

BACKGROUND We hypothesized that ex vivo donor allograft transfection with antisense oligodeoxynucleotide (AS ODN) would inhibit the expression of intercellular adhesion molecule (ICAM)-1, an important mediator of T-cell adhesion and costimulation, and therefore suppress acute cardiac rejection. METHODS Hearts were transfected ex vivo with AS, reverse AS ODN, or saline by applying 3 atm pressure for 45 min at 4 degrees C. Grafts were then transplanted into allogenic recipients +/- treatment with leukocyte function-associated antigen (LFA)-1 monoclonal antibody (mAb) (1.5 mg/kg intravenously), cyclosporine (2.5 mg/ kg/day p.o.), or rapamycin (0.025 mg/kg/day intraperitoneally). Reperfusion injury was assessed in grafts harvested at early time points using the myeloperoxidase, %wet weight, and %contraction band necrosis assays; transfection efficiency was assessed using fluorescent microscopy; and efficacy of ICAM-1 blockade was assessed using immunohistochemistry. Other grafts were followed until rejection with donor/third-party skin grafting, adoptive transfer, and interleukin 2 infusion studies in selected recipients. RESULTS Transfection was highly efficient (fluorescein isothiocyanate-ODN in 48+/-5% of total myocardial nuclei), nontoxic, and reduced the ICAM-1-positive area to 53+/-14% versus having no effect on MHC class I expression (n=4). The incidence of survival >60 days after AS ODN + LFA-1 monoclonal antibody was 75%, significantly higher than other regimens. CONCLUSION AS ODN hyperbaric transfection proved highly efficient, effective at ICAM-1 blockade, and induced cardiac allograft tolerance when combined with LFA-1 monoclonal antibody. This highly targeted alteration of allograft immunogenicity may have an important role in future immunosuppressive strategies.

Hypertrophic cardiomyopathy is a relatively common disease caused by genetic mutations that disrupt the sarcomere components. Although frequent in younger patients, it can present from infancy to old age. Its natural history can include sudden cardiac death, arrhythmias, and heart failure.1 Severe heart failure symptoms can result from left ventricular outflow tract (LVOT) obstruction, with or without systolic anterior motion of the mitral valve apparatus. For patients with LVOT obstruction, the outflow tract pressure gradient can be reduced using interventional techniques that have included surgical septal myectomy and alcohol septal ablation. According to a recent meta-analysis, septal myectomy has been superior in terms of reducing the gradient and preventing persistent conduction abnormalities.2 The initial reports of myectomy for symptomatic patients with LVOT obstruction described septal exposure by way of a left atriotomy and takedown of the anterior mitral leaflet. Given the challenge of septal visualization, this traditional approach was abandoned for the current standard, the Morrow procedure, which involves access to the ventricular septum by way of an aortotomy across the aortic valve. Two major limitations of both these procedures have been the required sternotomy and associated prolonged postoperative recovery. Surgical robotics has been used to routinely access the mitral valve by way of a left atriotomy. Therefore, a similar approach could be used to reintroduce the transatrial, transmitral approach to the hypertrophic septum. We have described a septal myectomy performed with a less-invasive, robot-assisted approach in a patient with recurrent symptomatic LVOT obstruction who had previously undergone an alcohol ablation procedure.

Introduction: Robotic-assisted coronary artery bypass grafting (r-CABG) requires the placement of ports bluntly through the chest wall. When removed, these ports create bleeding sites that can be difficult to detect and treat. This study evaluated whether a topical hemostatic agent placed locally within these sites helps to reduce bleeding and blood product requirements.Methods: We retrospectively analyzed outcomes for r-CABG cases where 5 mL of a flowable hemostatic agent was injected locally within all port sites (hemostat group, n = 62) compared with patients whose port sites were untreated (controls, n = 131). Outcomes included chest tube output, red blood cell (RBC) transfusions, length of hospital stay, and the risk of reoperation for bleeding. Analyses were adjusted for risk factors known to influence bleeding and Society of Thoracic Surgeons (STS) risk score as a weighted composite of variables, which controls for patient and clinical variables.Results: The 2 study groups had similar baseline characteristics and underwent the same r-CABG procedure. The hemostat group had significant reductions in RBC transfusion (24.2% versus 40.8% receiving blood; P = .026; 0.44 versus 1.39 U transfused postoperatively, P = .024). After adjustment for bleeding risks (using STS risk score), differences in transfusions remained significant. Reoperation rates for bleeding, length of stay, chest tube drainage, and intraoperative transfusions were not significantly different in the 2 groups.Conclusions: There was significantly reduced postoperative bleeding and less exposure to blood products in the hemostat group. These findings suggest that undetected bleeding from sites used for port access serves as an underappreciated source of morbidity after r-CABG.

Endoscopic vein harvesting (EVH) is the standard of care for coronary artery bypass grafting (CABG) in the United States, but recent comparisons with open harvesting suggest that conduit quality and outcomes may be compromised in EVH. To test the hypothesis that problems with EVH may relate to its learning curve and conduit quality, we analyzed the quality and early function of conduits procured by technicians with varying experience in EVH.Experienced (more than 900 cases, n=55 patients) and novice (less than 100 cases, n=30 patients) technicians performed EVH during CABG. Subsequently, optical coherence tomography (OCT) was used to examine the conduits for vascular injury, with segments identified as injured being further examined for gene expression with an array of genes related to tissue injury. Conduit diameter was measured intra- and postoperatively (day 5 and 6 months, respectively) with OCT and computed tomographic angiography.Endoscopic vein harvesting by novice harvesters resulted in a greater number of discrete graft injuries and greater expression of tissue-injury genes than EVH done by experienced harvesters. Regression analysis revealed an association between shear stress and early dilation of engrafted vessels (positive remodeling) (R2=0.48, p0.01). Injured veins showed blunted positive remodeling at 5 days after harvesting and a greater degree of late lumen loss at 6 months.Under normal conditions, intraluminal shear stress leads to positive remodeling of vein grafts during the first postoperative week. Injury to conduits, a frequent sequela of the learning curve for EVH, was a predictor of early graft failure and of blunted positive remodeling and greater negative remodeling of endoscopically harvested vein grafts. Given the current annual volume of cases in which EVH is used, rigorous monitoring of the learning curve for this procedure represents an important and unrecognized issue in public health.

Objective—We evaluated focused training in coronary artery anastomosis with a porcine heart model and portable task station. Methods—At “Boot Camp,” 33 first-year cardiothoracic surgical residents participated in 4-hour coronary anastomosis sessions (6–7 attending surgeons per group of 8–9 residents). At beginning, midpoint, and session end, anastomosis components were assessed on a 3-point rating scale (1 good, 2 average, 3 below average). Performances were video recorded and reviewed by 3 surgeons in a blinded fashion. Participants completed questionnaires at session end, with follow-up surveys at 6 months. Results—Ten to 18 end-to-side anastomoses with porcine model and task station were performed. Initial assessments ranged from 2.11 ± 0.58 (forceps use) to 2.44 ± 0.48 (needle angles). Midpoint scores ranged from 1.76 ± 0.63 (forceps use) to 1.91 ± 0.49 (needle angles). Session end scores ranged from 1.29 ± 0.45 (needle holder use) to 1.58 ± 0.50 (needle transfer and suture management and tension; P < .001). Video recordings confirmed improved performance (interrater reliability > 0.5). All respondents agreed that task station and porcine model were good methods of training. At 6 months, respondents noted that the anastomosis session provided a basis for training; however, only slightly more than half continued to practice outside the operating room. Conclusions—Four-hour focused training with porcine model and task station resulted in improved ability to perform anastomoses. Boot Camp may be useful in preparing residents for coronary anastomosis in the clinical setting, but emphasis on simulation development and deliberate practice is necessary.

Saphenous vein graft thrombosis after coronary artery bypass graft surgery is a poorly understood problem that lessens the benefits of this procedure. Recent studies highlight the importance of injury sustained at the time of saphenous vein graft procurement in the pathogenesis of acute graft thrombosis. In particular, damage to the graft endothelium that occurs secondary to ex vivo pressure distention, a common practice during vein harvest, leads to a loss of antithrombotic factors and increased activity of subendothelial prothrombotic factors. The prothrombotic potential of damaged grafts is further exacerbated by an ischemic storage interval and subsequent exposure to arterial flow conditions after grafting. A clearer understanding of the mechanisms by which endothelial disruption leads to acute saphenous vein graft thrombosis may result in interventions for improving our procurement techniques, interrupting the downstream effects of the damaged saphenous vein graft and/or discriminating damage that is beyond an acceptable threshold of thrombotic risk.

AIMS Reference values exist for endocardial but not for epicardial (EPI) substrate mapping in cases of cardiomyopathy-associated ventricular tachycardia. We sought to establish such values for EPI electrogram voltage, including areas with overlying fat. METHODS AND RESULTS Ten patients (six males) undergoing cardiac surgery were studied. After opening the pericardium, the distal bipole of an electrophysiology catheter was placed tangential to the EPI surface to obtain an electrogram recording. The bipole was tangentially rotated 90 degrees and the higher of the two amplitudes (mV) was taken as the local amplitude. Recordings were taken from normal left and right ventricular myocardium (n = 26 data points each), over thick (> or = 0.5 cm) fat at both ventricular bases (n = 16) and thin (

The radial artery's (RA) tendency to spasm when used as a bypass graft may relate to features of the RA itself. We imaged RA conduits before and after CABG in order to characterize intimal abnormalities that might relate to the risk of spasm.RA conduits from thirty-two CABG patients were imaged intraoperatively using catheter-based optical coherence tomography (OCT) and again on day 5 using 64-channel MDCT angiography. The change in luminal diameter between timepoints was measured in the proximal, mid and distal RA. "Spasm" was defined as focal or diffuse luminal narrowing to a diameter less than the target coronary. Lipid content in the RA was quantified by the degree of light attenuation on the OCT image.Postoperative spasm was diagnosed in 18 of 32 (56%) RA grafts with the distal RA showing the most severe change versus the mid and proximal portions (-24.1+/-43.2% vs. -15.3+/-40.7%, -9.0+/-42.5% change in diameter respectively, p0.01). The degree of attenuation of the OCT signal produced by the RA was strongly correlated with % diameter change (R=0.64, p=0.0005) and was significantly more pronounced in grafts with spasm versus no spasm (-1.97+/-0.61mm(-1) vs. -0.81+/-0.57mm(-1), p0.0001). Histology confirmed lipid deposits in areas of RA with strong attenuation.RA conduits otherwise considered acceptable for bypass grafting were often found by OCT imaging to have a substantial amount of lipid, which in turn strongly relates to the risk of postoperative spasm. Screening conduits based on characteristics of intimal quality may improve results following RA grafting.

Soluble ST2 (sST2) is released from myocytes in response to mechanical overload and predicts poor outcome in heart failure and myocardial infarction. We evaluated the capability of early sST2 release after coronary artery bypass surgery (CABG) to predict mortality during the first postoperative year. We prospectively evaluated sST2 baseline prior to CABG (BL), immediately after CABG (post), and 24h and 72h. The primary endpoint of the study was all-cause mortality at 1 year. Of the 210 patients enrolled, death occurred in 3 (1.5%) within 30 days and 20 (9.5%) by 1 year. sST2 levels did not change immediately post-CABG (BL: 0.32±0.42, post: 0.42±0.46) but became significantly elevated at 24h and 72h (3.39±3.08, 0.95±1.04 ng/ml; P