The Anti-Apoptotic Effect of Ranolazine on Cerebral Protection during Cardiopulmonary Bypass and Carotid Artery Surgery

Background

We aimed to determine the usability of ranolazine (Rn) as a neuroprotective during cardiac surgeries and carotid artery interventions where cerebral blood flow is interrupted.

Methods

Female Wistar albino rats were used. The rats were divided into 4 groups of 8 rats each. The first group (Group 1) was the control group. Group 2 underwent ischemia induction but was not treated with Rn. Group 3 received 25 mg/kg/day and Group 4 50 mg/kg/day Rn intraperitoneally, starting 3 days before ischemia induction. Bilateral carotid arteries were explored and clamped simultaneously. Ischemia was induced for 15 minutes. After 72 hours, the experimental animals were sacrificed.

Results

Superoxide dismutase, alkaline phosphatase, and interleukin 6 levels were similar among the 4 groups. Acetylcholine esterase (Group 3: p = 0.007, Group 4: p = 0.002), tumor necrosis factor-alpha (Group 4: p = 0.01), and annexin V (Group 3: p = 0.001) levels were statistically significantly lower in the Rn-treated groups. Malondialdehyde (Group 3: p = 0.003, Group 4: p = 0.009), reduced glutathione (Group 4: p = 0.04), acid phosphatase (Group 3: p = 0.04), noradrenaline (Group 3: p = 0.01), and Bcl-2 (Group 4: p = 0.004) levels were significantly higher in the Rn-treated groups.

Conclusions

The results of this study demonstrated the antiapoptotic effect of Rn in a brain ischemia-reperfusion model of rats receiving Rn before the procedure.

Frequency of subclavian artery stenosis in patients with mammarian artery coronary bypass and suspected coronary artery disease progression

We retrospectively analyzed patient records of all patients with a history of internal mammarian artery (IMA) coronary bypass undergoing coronary angiography at two cardiovascular centers between January 1st 1999 and December 31st 2019. A total of 11,929 coronary angiographies with or without percutaneous coronary intervention were carried out in 3921 patients. Our analysis revealed 82 (2%) patients with documented subclavian artery stenosis. Of these, 8 (10%) patients were classified as having mild, 18 (22%) moderate, and 56 (68%) severe subclavian artery stenosis. In 7 (9%) patients with subclavian artery stenosis, angiography revealed occlusion of the IMA graft. 26 (32%) patients with severe subclavian artery stenosis underwent endovascular or surgical revasculararization of the subclavian artery. In this retrospective multicenter study, subclavian artery stenosis was a relevant finding in patients with an internal mammarian artery coronary bypass graft undergoing coronary angiography. The development of dedicated algorithms for screening and ischemia evaluation in affected individuals may improve treatment of this potentially underdiagnosed and undertreated condition.

In patients undergoing coronary artery bypass grafting is semi-skeletonization superior to pedicled harvesting of the left internal mammary artery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was, 'in patients undergoing coronary artery bypass grafting is semi-skeletonized harvesting superior to pedicled harvesting of the left internal mammary artery (LIMA) in terms of conduit length, flow, rate of sternal wound infections and post-operative bleeding?'. Altogether, 235 papers were found using the reported search, of which 5 represented the best evidence to answer the clinical question. Three studies were cohort studies and 2 were randomized controlled trials. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. One randomized controlled trial showed superiority with semi-skeletonized harvesting in terms of conduit length (P < 0.001), flow (P = 0.004) and diastolic filling (P = 0.005). Three studies included data on surgical wound infections/mediastinitis, all of which reported n = 0. One randomized controlled trial and 3 cohort studies reported that semi-skeletonized harvesting reduced postoperative bleeding. No studies reported a statistically significant difference in operative time. This review suggests that semi-skeletonized harvesting could possibly be associated with favourable outcomes when compared to pedicled harvesting with respect to graft length and flow, and lower postoperative bleeding, without increasing operative time; although there is insufficient data to compare sternal wound infections or long-term outcomes. In conclusion, the limited evidence base prevents robust informed decision-making when comparing both techniques.

Severe baffle leak after Takeuchi repair successfully treated with coronary bypass and percutaneous baffle closure: a case report

Background

Anomalous left coronary artery from the pulmonary artery is a rare congenital abnormality that requires surgical correction.

Case summary

We describe the case of a 33-year-old female with a history of anomalous left coronary artery of the pulmonary artery who presents with exertional angina. She underwent a Takeuchi repair that was complicated by a baffle leak. She was successfully treated with left internal mammary artery-left anterior descending (LAD) bypass grafting and percutaneous baffle leak closure.

Discussion

The Takeuchi procedure involves the creation of an aortopulmonary window and an intrapulmonary tunnel that 'baffles' the aorta to the ostium of the anomalous left coronary artery. The most common late complication of the Takeuchi procedure is the presence of a baffle leak. Percutaneous baffle leak occlusion via vascular plug and coronary bypass of the LAD can successfully treat a baffle leak with excellent short-term follow-up.

Coronary Artery Bypass: Review of Surgical Techniques and Impact on Long-Term Revascularization Outcomes

Coronary revascularization for multivessel disease remains a common and costly source of hospitalizations in the United States. Surgical techniques influence outcomes for coronary bypass and also affect the need for percutaneous coronary intervention in the future. As more radial access has been used for coronary angiography, consideration for use of the radial artery as a surgical conduit remains unclear. Saphenous vein grafts are commonly used for coronary bypass, however long-term patency remains suboptimal, and is also associated with a higher risk of adverse events with percutaneous coronary intervention. Thus, understanding the interplay between coronary bypass techniques and percutaneous coronary intervention has become increasingly important.

Numerical study of hemodynamics in a complete coronary bypass with venous and arterial grafts and different degrees of stenosis

Cardiovascular diseases are among the leading causes of death in the world. The coronary blockage is one of most common types of these diseases that in the majority of cases has been treated by bypass surgery. In the bypass surgery, a graft is implemented to alter the blocked coronary and allow the blood supply process. The hemodynamic characteristics of the bypass strongly depend on the geometry and mechanical properties of the graft. In the present study, the fluid-structure interaction (FSI) analysis is conducted to investigate the bypass performance for a thoracic artery as well as a saphenous vein graft. Blood flow introduces a pressure on the walls of the graft which behaves as a hyperelastic material. A complete coronary bypass with stenosis degrees of 70% and 100% is modeled. To consider the nonlinear stress-strain behavior of the grafts, a five parameter Mooney-Rivlin hyperplastic model is implemented for the structural analysis and blood is assumed to behave as a Newtonian fluid. The simulations are performed for a structured grid to solve the governing equations using finite element method (FEM). The results show that wall shear stress (WSS) for saphenous vein is larger than that of thoracic artery while the total deformation of the thoracic artery is larger compared to the saphenous vein. Also, for the venous grafts or lower stenosis degree, the oscillatory shear index (OSI) is higher at both left and right anastomoses meaning that venous grafts as well as lower degree of stenosis are more critical in terms of restenosis.

The Anti-Inflammatory Effects of Anacardic Acid on a TNF-α - Induced Human Saphenous Vein Endothelial Cell Culture Model

BACKGROUND AND OBJECTIVE

Coronary bypass operations are commonly performed for the treatment of ischemic heart diseases. Coronary artery bypass surgery with autologous human saphenous vein maintains its importance as a commonly used therapy for advanced atherosclerosis. Vascular inflammation-related intimal hyperplasia and atherosclerotic progress have major roles in the pathogenesis of saphenous vein graft disease.

METHODS

In our study, we investigated the effect of anacardic acid (AA), which is a bioactive phytochemical in the shell of Anacardium occidentale, on atherosclerosis considering its inhibitory effect on NF-κB. We observed relative ICAM-1 and NF-κB mRNA levels by qRT-PCR method in a TNF-α- induced inflammation model of saphenous vein endothelial cell culture after 0.1, 0.5, 1 and 5 μM of AA were applied to the cells. In addition, protein levels of ICAM-1 and NF-κB were evaluated by immunofluorescent staining. The results were compared between different concentrations of AA, and also with the control group.

RESULTS

It was found that 5 μM, 1 μM and 0.5 μM of AA had toxic effects, while cytotoxicity decreased when 0.1 μM of AA was applied both alone and with TNF-α. When AA was applied with TNF-α, there was a decrease and suppression in NF-κB expression compared with the TNF-α group. TNF-α-induced ICAM-1 expression was significantly reduced more in the AA-applied group than in the TNF-α group.

CONCLUSION

In accordance with our results, it can be said that AA has a protective role in the pathogenesis of atherosclerosis and hence in saphenous vein graft disease.

Spontaneous "Coronary Bypass" in a Paediatric Transplanted Heart

We report an asymptomatic 5-year-old boy with coronary artery fistulas to pulmonary parenchyma and to systemic thoracic arteries, like a "natural bypass", detected during a coronary angiography performed 11 months after his heart transplant. One year later, a new coronary angiography showed no fistula. Some changes to immunosuppressive therapy during this time could be related to this evolution.

Clinical Efficacy of а Medical Centre- and Home-based Cardiac Rehabilitation Program for Patients with Coronary Heart Disease After Coronary Bypass Graft Surgery

BACKGROUND

Rehabilitation measures are crucial for maintaining clinical benefits of coronary artery bypass grafting (CABG) surgery. We evaluated the clinical efficacy of a medical centre- and home-based cardiac rehabilitation (CR) for patients after CABG in an out-patient setting.

METHODS

The study included 36 male patients 3-8 weeks after CABG that were randomly assigned to either study or control group. Patients from the study group performed a 60 min excercise in controlled setting 3 times a week for 4 months followed by home-based excercise later on, while patients from the control group only received a recommendation to perform the excercise at home in an uncontrolled setting. Total duration of the follow-up was 12 months.

RESULTS

Physical endurance in the study group increased by 32.6% (p <0.05) in comparison to baseline after 4 months, and was maintained at this level after 12 months, while in the control group, an improvement of 9.8% (p <0.05) was observed after 12 months. Moreover, patients from the study group demonstrated a stable level of such risk factors as blood total and low-density lipoprotein cholesterol, while in the control group, these parameters increased by 10.2% (p <0.05) and 15.6% (p <0.05) respectively by the end of follow-up. Controlled medical centre-based exercise resulted in improvement of patients' quality of life and reduction of cardiovascular complications (11.1% against 39.2% in the control group).

CONCLUSION

The integral (medical centre and home-based) stage III CR program after CABG helped reducing cardiovascular risk factors, and improved clinical parameters and functional capacity of patients.

Giant coronary aneurysms producing chest pain

Background

Coronary artery aneurysms (CAA) are defined as localized coronary artery dilations more than 1.5 times the diameter of the adjacent segments [1]. Giant coronary aneurysms (GCAA) are unusual and aneurysms on the left side are even rarer. Mechanisms are unclear, but seem predominated by atherosclerosis. Until now, management of giant coronary aneurysm is still unclear.

Case presentation

A 62-year-old man, presented a 4-month history of progressive chest pain aggravated by physical CAAs: 3 on the right coronary artery (RCA), including a giant one, and one on the intermediate branch. Intraoperatively, we found two proximal RCA CAAs of 2 cm each, a 6 cm distal RCA CAA partially thrombosed, and a 3 cm CAA on the intermediate branch.

The two largest CAAs were resected and two saphenous graft bypasses were performed.

Conclusions

Treatment options include medical treatment (antiaggregation, anticoagulation), percutaneous coronary angioplasty and surgery. Results of observational or conservative management in the few cases of GCAA described in literature, appear to have poor results. Surgery is a good option with low operative risk, especially in giant coronary aneurysms.

Electronic supplementary material

The online version of this article (10.1186/s13019-019-0872-4) contains supplementary material, which is available to authorized users.

Increased platelet reactivity and platelet-leukocyte aggregation after elective coronary bypass surgery

Inflammatory mechanisms are activated, and thrombotic complications occur during the initial months after coronary artery bypass grafting (CABG). Therefore, changes over time of platelet activation and platelet-leukocyte interactions after CABG are of interest. Whole-blood flow cytometry was performed before, and 4-6 days, one month, and three months after elective CABG in 54 men with stable coronary artery disease treated with acetylsalicylic acid (ASA). Single platelets and platelet-leukocyte aggregates (PLAs) among monocytes (P-Mon), neutrophils (P-Neu), and lymphocytes (P-Lym) were studied without and with stimulation by submaximal concentrations of ADP, thrombin, and the thromboxane analog U46619. White blood cell counts were increased during the initial postoperative course, and platelet counts were increased after one month. Platelet P-selectin expression was significantly enhanced at one month when stimulated by thrombin and U46619 and at three months with ADP and thrombin. All PLAs subtypes were increased at one month without stimulation in vitro. P-Mon and P-Neu stimulated by ADP, thrombin, or U46619 were significantly increased one month after the operation but decreased compared to baseline at three months. Agonist stimulated P-Lyms were increased at one month and remained increased at three months after ADP stimulation. There was significant platelet activation and formation of PLAs unstimulated and after agonist stimulation by ADP, thrombin, and a thromboxane analog after CABG in patients with stable coronary artery disease irrespective of ASA treatment. Changes observed up to three months after CABG support further studies of the clinical implications of protracted increases in platelet activation and platelet-leukocyte interactions.

Long term outcomes of radial artery grafting in patients undergoing coronary artery bypass surgery

Single arterial left internal thoracic artery (LITA) based coronary artery bypass surgery (LITA-SABG) has been the principal revascularization strategy for over 25 years across all patient demographics. In line with the current emphasis being placed on personalized medicine, which tailors individual, patient-specific therapy to optimize outcomes, coronary artery bypass grafting (CABG) techniques have also evolved to achieve enhanced results among specific groups of patients with coronary artery disease. Most notable has been the development of multi-arterial bypass grafting (MABG) techniques, using either the radial artery (RA) or the right internal thoracic artery (RITA) in conjunction with the LITA, as both techniques have been shown to enhance long term survival of CABG patients. This article reviews the latest data on the long-term outcomes of RA-MABG and considers its impact in various sub-cohorts of CABG that are increasingly being treated by cardiac surgeons. The primary aim of this review is to highlight the advantages of RA-MABG over LITA-SABG and thereby potentiate its adoption into clinical practice. Our secondary aim is to summarize the results of RA-MABG in specific CABG sub-cohorts, to more closely align CABG surgery with the emerging consensus that personalized medicine enhances healthcare value.

Robotically Assisted Minimally Invasive Off-Pump Coronary Artery Bypass Surgery in a Patient With Permanent Tracheostomy

BACKGROUND

Patients with a permanent tracheostomy requiring coronary surgery represent a unique challenge, being at increased risk of sternal wound complications, mediastinitis and stoma necrosis. Several techniques have been described including manubrium sparing sternotomy, thoracoscopic internal mammary harvest and hybrid revascularisation.

METHODS

We report a case of robotic assisted (daVinci^®Xi™ Surgical System) total arterial off-pump revascularisation in a patient with previous laryngectomy and permanent tracheostomy. The main advantage of this approach was to minimise the risk of postoperative sternal complication and mediastinatis, whilst still providing the prognostic benefit of total arterial grafting and the neurological advantage of the aorta no-touch technique.

Patient-Specific Simulations Reveal Significant Differences in Mechanical Stimuli in Venous and Arterial Coronary Grafts

Mechanical stimuli are key to understanding disease progression and clinically observed differences in failure rates between arterial and venous grafts following coronary artery bypass graft surgery. We quantify biologically relevant mechanical stimuli, not available from standard imaging, in patient-specific simulations incorporating non-invasive clinical data. We couple CFD with closed-loop circulatory physiology models to quantify biologically relevant indices, including wall shear, oscillatory shear, and wall strain. We account for vessel-specific material properties in simulating vessel wall deformation. Wall shear was significantly lower (p = 0.014*) and atheroprone area significantly higher (p = 0.040*) in venous compared to arterial grafts. Wall strain in venous grafts was significantly lower (p = 0.003*) than in arterial grafts while no significant difference was observed in oscillatory shear index. Simulations demonstrate significant differences in mechanical stimuli acting on venous vs. arterial grafts, in line with clinically observed graft failure rates, offering a promising avenue for stratifying patients at risk for graft failure.

Do waiting times affect health outcomes? Evidence from coronary bypass

Long waiting times for non-emergency services are a feature of several publicly-funded health systems. A key policy concern is that long waiting times may worsen health outcomes: when patients receive treatment, their health condition may have deteriorated and health gains reduced. This study investigates whether patients in need of coronary bypass with longer waiting times are associated with poorer health outcomes in the English National Health Service over 2000-2010. Exploiting information from the Hospital Episode Statistics (HES), we measure health outcomes with in-hospital mortality and 28-day emergency readmission following discharge. Our results, obtained combining hospital fixed effects and instrumental variable methods, find no evidence of waiting times being associated with higher in-hospital mortality and weak association between waiting times and emergency readmission following a surgery. The results inform the debate on the relative merits of different types of rationing in healthcare systems. They are to some extent supportive of waiting times as an acceptable rationing mechanism, although further research is required to explore whether long waiting times affect other aspects of individuals' life.

Meta-analysis of concomitant mitral valve repair and coronary artery bypass surgery versus isolated coronary artery bypass surgery in patients with moderate ischaemic mitral regurgitation

Ischaemic mitral regurgitation (IMR) is a complication of coronary artery disease with normal chordal and leaflet morphology. Controversy surrounds the issue of appropriate surgical management of moderate IMR. With the present meta-analysis, we aimed to determine whether the addition of mitral valve (MV) repair to coronary artery bypass grafting (CABG) improved clinical outcome over CABG alone in patients with moderate IMR. Databases were searched for studies reporting on clinical outcomes after CABG and MV repair or CABG alone for moderate IMR. Clinical end-points were operative mortality, survival, New York Heart Association (NYHA) class ≥2 and MR grade ≥2 at last follow-up. A total of five observational and four randomized controlled trials (RCTs) were identified. The mean follow-up was 2.7 years. An analysis of all studies revealed increased operative risk in the concomitant CABG and MV repair group {risk ratio [RR] 2.02 [95% confidence interval (CI) 1.15, 3.56], P = 0.01, I(2) = 0%}. However, an analysis of RCTs only showed that the operative risk was equivalent [RR 1.05 (95% CI 0.34, 3.30), P = 0.93, I(2) = 0%]. Pooled hazard ratio (HR) on survival did not favour either procedure [all studies: HR 1.08 (95% CI 0.77, 1.50), P = 0.66, I(2) = 0%; RCTs only: HR 0.89 (95% CI 0.47, 1.70), P = 0.73, I(2) = 0%]. The incidence of exercise intolerance quantified as NYHA class ≥2 was similar between groups (all studies: RR 0.72 (95% CI 0.42, 1.24), P = 0.24, I(2) = 77%; RCTs only: RR 0.61 (95% CI 0.24, 1.55), P = 0.30, I(2) = 83%]. Risk of residual MR grade ≥2 was higher in the CABG only group [all studies: RR 0.30 (95% CI 0.16, 0.60), P < 0.001, I(2) = 83%; RCTs only: RR 0.20 (95% CI 0.04, 0.90), P = 0.04, I(2) = 72%]. There is neither increased operative mortality nor survival benefit associated with concomitant CABG and MV repair for IMR of moderate degree over CABG alone. Further studies with long-term follow-up data and sub-group analyses of current data are needed to define a subset of patients whose survival and functional status may improve with the concomitant MV repair.

Clinical SYNTAX Score Can Predict Acute Kidney Injury following On-Pump but Not Off-Pump Coronary Artery Bypass Surgery

BACKGROUND

The complexity of coronary artery disease is usually a neglected factor in risk stratification systems. We aimed to analyze the discriminative ability of the clinical SYNTAX score (CSS) for acute kidney injury (AKI) following on- and off-pump coronary artery surgery.

METHODS

A total of 193 patients were reviewed in this study. Patients were divided into two groups according to the surgical procedure (group I: off-pump coronary artery bypass grafting, n = 89; group II: on-pump coronary artery bypass grafting, n = 104). Preoperative demographic data, the CSS and postoperative renal functions were evaluated. The postoperative AKI classification was made using the RIFLE (Risk, Injury, Failure, Loss of function, and End-stage renal disease) criteria.

RESULTS

Postoperative AKI occurred in 14 of 89 patients (15.7%) in group I and in 29 of 104 patients in group II (27.8%; p = 0.046). The CSS did not vary much between the groups (31.52 ± 13.08 vs. 29.89 ± 15.70; p = 0.638). In group I, the CSS was not different between patients with AKI and those without AKI (30.167 ± 3.93 vs. 31.91± 14.75; p = 0.78). In group II, the CSS was 36.85 ± 18.33 in patients with AKI and 28.02 ± 12.32 in those without, and the difference was significant (p = 0.02). The discriminative ability of the CSS for postoperative AKI using the AUC analysis was 0.500 in group I and 0.840 in group II.

CONCLUSION

The CSS may be a simple and successful means of risk prediction of postoperative AKI in on-pump coronary artery surgery.

Asymptomatic anomalous origin of left anterior descending artery from the pulmonary artery and multiple atherosclerotic stenoses revealed by silent ischaemia

Anomalous origin of the left coronary artery from the pulmonary artery is a rare congenital disease responsible for a high mortality rate in childhood. Here, we report for the first time the case of an asymptomatic 61-year old patient showing a combination of anomalous origin of the left anterior descending artery from pulmonary artery and atherosclerotic stenosis in both the right coronary artery and the left circumflex artery without anomalous origin.

Oral neutrophils are an independent marker of the systemic inflammatory response after cardiac bypass

Background

Cardiopulmonary bypass (CPB) is an immuno-reactive state where neutrophils are activated and accumulate in different tissues. Edema and tissue necrosis are the most common sequelae observed, predominantly in the lungs, kidneys, and heart, heralding significant risk for postoperative complications. No method exists to noninvasively assess in vivo neutrophil activity. The objective of this study was to determine if neutrophil recruitment to the oral cavity would correlate with specific biomarkers after coronary bypass surgery (CPB).

Methods

We conducted a single site prospective observational study including non-consecutive adult patients undergoing elective, on-pump CPB. Blood and either oral cavity rinses or swabs were collected pre- and post-CPB. Absolute neutrophil counts from oral samples and serum biomarkers were measured. The association between neutrophil recruitment to the oral cavity, biomarkers and outcomes after CPB were analyzed.

Results

CPB was associated with statistically significant increases in oral and blood neutrophil counts, as well as an increase in certain biomarkers over preoperative baseline. Peripheral blood neutrophil count were increased at all time points however statistically significant differences in median oral neutrophil counts were observed only at the time point immediately postoperative, and in what seems to be two unique patient populations (p < 0.001; group 1, median: 1.6×10⁵, Interquartile range [IQR], 1.1×10⁵ - 4.8×10⁵, and group 2, median: 1.9×10⁶, IQR, 8.7×10⁵ - 4.0×10⁶).

Conclusions

CPB is associated with a transient increase in oral neutrophils that may correlate with the systemic inflammatory response; oral neutrophils may have the ability to discriminate and identify unique patient populations based on their tissue migration.

Severe stenosis of left coronary artery originating from right sinus of Valsalva treated with off-pump coronary artery bypass surgery

Anomalous origin of the left coronary artery originating from the opposite sinus of Valsalva is a coronary anomaly with a consistently low prevalence rate. Different patterns have been described for this type of anomaly with respect to the position and course of the coronary arteries. The interarterial type can be considered a malignant variant, as it is characterized by a left main coronary artery that is positioned between the aortic root and the pulmonary artery root, and it frequently presents with syncope or aborted sudden cardiac death. Other symptoms or clinical presentations include the presence or development of angina, acute myocardial infarction and ventricular tachycardia. We present the case of a 49-year old man who presented with a new onset of chest pain; a coronary angiogram showed an anomalous left main coronary artery arising from the right Valsalva sinus, accompanied by a long and severe stenosis. It was found that multi-scan cardiac tomography is very useful in identifying the position of the coronary arteries when coronary anomalies occur.

Relationshi̇p between atrial fibrillation and coronary bypass surgery

OBJECTIVE

Atrial fibrillation (AF) is the most common arrhythmia seen after coronary artery surgery. The purpose this study was to determine incidence of AF that develops after coronary surgery and the factors affecting its development.

METHODS

Four hundred and forty eight patients who had coronary bypass surgery between February 2007 and September 2011 in the Cardiovascular Surgery Clinic were included in the study. Patients with history of chronic renal failure, redo coronary bypass surgery, valvular disease, thyroid disease, ventricular aneurysm and treatment with beta-blockers were excluded from the study of EF.

RESULTS

Two hundred and ninety nine patients were male and 149 were female and their age varied between 38 and 85 and their mean age was 61±5. Surgery was performed on beating heart on 178 patients and the others were operated with cardiopulmonary bypass (CPB). Advanced age, male sex and history of hypertension was more in AF developed patient group. There was no difference between AF developed group and the other group in terms of diameter of left atrium, ejection fraction (EF), CPB time and cross clamp time.

CONCLUSION

Advanced age, male sex, hypertension and prolonged P-wave duration are the factors that are associated with AF after coronary surgery. Avoidance of CPB does not decrease AF development.

Cardiac-targeting transfection of tissue-type plasminogen activator gene to prevent the graft thrombosis and vascular anastomotic restenosis after coronary bypass

AIM

To observe the tissue-type plasminogen activator gene (t-PA) plasmid packaged with albumin nanoparticles crosslinked to albumin ultrasound microbubbles for targeting transfection to myocardium to prevent the graft thrombosis and vascular anastomotic restenosis after coronary bypass.

METHODS

A dog model of coronary bypass using the autoallergic saphenous vein as the graft was made. A highly expressive t-PA gene plasmid packaged with albumin nanoparticles crosslinked to albumin ultrasound microbubbles was constructed. Targeting myocardial transfection was performed with this gene vector under the aid of therapeutic ultrasound(1MHz, 1.5 w/cm2, 6minutes, intravenously) after the bypass. The expression of t-PA in myocardium was detected with a multiclonal antibody to t-PA by the indirect immunohistochemical method. Venous blood t-PA and D-dimer contents were tested before and 1, 2 and 4weeks after the operation. The effects of this gene vector on thrombosis of the grafts and the coronary intimal hyperplasia around the anastomotic stoma were observed using a routine pathological examination, a morphometry for intimal thickness and area and the immuno-histochemical stain with a monoclonal antibody to PCNA for estimating the intimal SMC proliferation.

RESULTS

The effective expression of t-PA protein by myocardium was obtained, followed by the persistent raises of blood t-PA and D-dimer 1, 2 and 4weeks after the transfection. Thrombosis of the grafts was successfully restrained. The expression of PCNA by coronary intimal vSMCs and intimal hyperplasia were remarkablely reduced.

CONCLUSION

This t-PA gene targeting vector could be used to prevent the dog thrombosis, which provided the experimental identification for prevention on human thrombotic diseases.

Protective constriction of coronary vein grafts with knitted nitinol

OBJECTIVES

Different flow patterns and shear forces were shown to cause significantly more luminal narrowing and neointimal tissue proliferation in coronary than in infrainguinal vein grafts. As constrictive external mesh support of vein grafts led to the complete suppression of intimal hyperplasia (IH) in infrainguinal grafts, we investigated whether mesh constriction is equally effective in the coronary position.

METHODS

Eighteen senescent Chacma baboons (28.8 ± 3.6 kg) received aorto-coronary bypass grafts to the left anterior descending artery (LAD). Three groups of saphenous vein grafts were compared: untreated controls (CO); fibrin sealant-sprayed controls (CO + FS) and nitinol mesh-constricted grafts (ME + FS). Meshes consisted of pulse-compliant, knitted nitinol (eight needles; 50 μm wire thickness; 3.4 mm resting inner diameter, ID) spray attached to the vein grafts with FS. After 180 days of implantation, luminal dimensions and IH were analysed using post-explant angiography and macroscopic and histological image analysis.

RESULTS

At implantation, the calibre mismatch between control grafts and the LAD expressed as cross-sectional quotient (Qc) was pronounced [Qc = 0.21 ± 0.07 (CO) and 0.18 ± 0.05 (CO + FS)]. Mesh constriction resulted in a 29 ± 7% reduction of the outer diameter of the vein grafts from 5.23 ± 0.51 to 3.68 ± 0 mm, significantly reducing the calibre discrepancy to a Qc of 0.41 ± 0.17 (P < 0.02). After 6 months of implantation, explant angiography showed distinct luminal irregularities in control grafts (ID difference between widest and narrowest segment 74 ± 45%), while diameter variations were mild in mesh-constricted grafts. In all control grafts, thick neointimal tissue was present [600 ± 63 μm (CO); 627 ± 204 μm (CO + FS)] as opposed to thin, eccentric layers of 249 ± 83 μm in mesh-constricted grafts (ME + FS; P < 0.002). The total wall thickness had increased by 363 ± 39% (P < 0.00001) in CO and 312 ± 61% (P < 0.00001) in CO + FS vs 82 ± 61% in ME + FS (P < 0.007).

CONCLUSIONS

In a senescent non-human primate model for coronary artery bypass grafts, constrictive, external mesh support of saphenous veins with knitted nitinol prevented focal, irregular graft narrowing and suppressed neointimal tissue proliferation by a factor of 2.5. The lower degree of suppression of IH compared with previous infrainguinal grafts coincided with a lesser reduction of calibre mismatch in the coronary grafts.

[Not Available]

Aim:

We aimed to report our postoperative results in elderly patients that had off-pump coronary bypass grafting.

Method:

Data of 173 patients with isolated coronary bypass 70 years of age or older were retrospectively evaluated. One month follow-up data were evaluated in all patients. After getting verbal informed consent a total of 91 patients were included in the quality of life assessment via EuroQoL form. The data of patients with age of 70-74 and 75 or older were compared.

Results:

The mean ages of patients at age of 70-74 and ≥75 were 71.69±0.16 and 76.81±0.23 years; respectively. Eleven cases had in-hospital mortality (%6 of 173 patients). The mean follow-up period for the group that were reached for EuroQoL assessment was 46,3 ± 20,8 months. The percent of cases among the whole study group that had participated in the quality of life questionnaire were in good condition in terms of mobility, self-care, usual activities, pain/discomfort, anxiety/depression were %75, %87, %81, %92 and %89; respectively.

Discussion:

Off-pump coronary bypass operation may be safely used in elderly patients with high quality of life and low morbidity and mortality.

Comparison of inflammatory response following coronary revascularization with or without cardiopulmonary bypass

BACKGROUND

It is well known that conventional coronary revascularization is associated with a pronounced systemic inflammatory response due to the application of cardiopulmonary bypass (CPB).

OBJECTIVE

To compare the effects of coronary artery bypass grafting (CABG) with (on-pump) or without (off-pump) extra-corporeal circulation observing certain inflammatory response parameters.

METHODS

TWENTY PATIENTS UNDERGOING CABG WITH (CPB GROUP: 10 patients) or without (off-pump coronary artery bypass grafting [OPCAB] group: 10 patients) CPB were enrolled in this prospective, randomized study. Blood samples were collected three times during the operation and on postoperative days 1, 2, 3 and 7. The plasma level of proinflammatory cytokine tumor necrosis factor (TNF)-alpha was measured by enzyme-linked immunosorbent assay method following stimulation, and the expression of adhesion molecules (CD11, CD18) of leukocytes were determined by flow cytometry. Furthermore, white blood cell (WBC) and neutrophil count were carried out.

RESULTS

The WBC and neutrophil counts rose markedly in both groups following the operation and remained at this increased level during the observation period. There was a significant difference in WBC and neutrophil counts between the two groups of patients on postoperative day 7. A significant difference in the level of TNF-alpha was found between the two groups on postoperative day 2 (P<0.05). An intense increase was observed with CPB, which significantly exceeded the values of the OPCAB group without extracorporeal circulation in the early postoperative period. The CD11a and CD18 expression of leukocytes decreased during the operation and on postoperative day 1; thereafter, it increased markedly. There was a significant difference in adhesion molecule expression between the two groups on postoperative day 2.

CONCLUSION

The investigation revealed that inflammatory response reactions following extracorporeal circulation could be reduced significantly using the off-pump technique.