Effect of skeletonization of the internal thoracic artery for coronary revascularization on the incidence of sternal wound infection

Comprehensive comparison of different BITA graft configurations: a computational study integrating TTFM and hemodynamic predictors

Bilateral internal thoracic artery (BITA) grafting utilizes both the left (LITA) and right (RITA) internal thoracic arteries simultaneously and is recommended in the literature. However, the optimal configuration for BITA grafting remains uncertain. In this study, three-dimensional numerical simulations of different BITA configurations were conducted to identify the optimal configuration and assess their performance using the fractional flow reserve (FFR), transit time flow meter (TTFM), and hemodynamic parameters. The vessel geometry of a patient who underwent a BITA grafting with a Y-graft configuration was extracted from CT angiography images, and three other configurations (pedicle, LITA as free graft, and RITA as free graft) with different degrees of stenosis were reconstructed. Results showed that, in mild to moderate stenosis (FFR > 0.7), the Y-graft configuration was less favorable for graft quality, as it had higher pulsatility index (PI) and systolic reverse flow (SRF) values, leading to increased competitive flow. However, as stenosis severity increased, these differences decreased, and for severe stenosis, the results were similar for all BITA configurations. Furthermore, the results showed that the Y-graft configuration was less effective in reducing TAWSS compared to other configurations. Oscillatory shear index (OSI) and relative residence time (RRT) did not show significant differences.

Intra-operative and post-operative management of conduits for coronary artery bypass grafting: a clinical consensus statement of the European Society of Cardiology Working Group on Cardiovascular Surgery and the European Association for Cardio-Thoracic Surgery Coronary Task Force

The structural and functional integrity of conduits used for coronary artery bypass grafting is critical for graft patency. Disruption of endothelial integrity and endothelial dysfunction are incurred during conduit harvesting subsequent to mechanical or thermal injury and during conduit storage prior to grafting, leading to acute thrombosis and early graft failure. Late graft failure, in particular that of vein grafts, is precipitated by progressive atherogenesis. Intra-operative management includes appropriate selection of conduit-specific harvesting techniques and storage solutions. Arterial grafts are prone to vasospasm subsequent to surgical manipulation, and application of intra-operative vasodilatory protocols is critical. Post-operative management includes continuation of oral vasodilator therapy and selection of antithrombotic and lipid-lowering agents to attenuate atherosclerotic disease progression in conduits. In this review, the scientific evidence underlying the key aspects of intra- and post-operative management of conduits for coronary artery bypass grafting is examined. Clinical consensus statements for best clinical practice are provided, and areas requiring further research are highlighted.

Intra-operative and post-operative management of conduits for coronary artery bypass grafting: a clinical consensus statement of the European Society of Cardiology Working Group on Cardiovascular Surgery and the European Association for Cardio-Thoracic Surgery Coronary Task Force

The structural and functional integrity of conduits used for coronary artery bypass grafting is critical for graft patency. Disruption of endothelial integrity and endothelial dysfunction are incurred during conduit harvesting subsequent to mechanical or thermal injury and during conduit storage prior to grafting, leading to acute thrombosis and early graft failure. Late graft failure, in particular that of vein grafts, is precipitated by progressive atherogenesis. Intra-operative management includes appropriate selection of conduit-specific harvesting techniques and storage solutions. Arterial grafts are prone to vasospasm subsequent to surgical manipulation, and application of intra-operative vasodilatory protocols is critical. Post-operative management includes continuation of oral vasodilator therapy and selection of antithrombotic and lipid-lowering agents to attenuate atherosclerotic disease progression in conduits. In this review, the scientific evidence underlying the key aspects of intra- and post-operative management of conduits for coronary artery bypass grafting is examined. Clinical consensus statements for best clinical practice are provided, and areas requiring further research are highlighted.

Long-term results following off-pump coronary-artery bypass grafting in left ventricular dysfunction

Severe left ventricular (LV) dysfunction is an independent risk factor for early and long-term mortality after coronary-artery bypass grafting (CABG). Off-pump CABG (OPCAB) significantly reduces the early incidence of major complications in high-risk patients. Moreover, bilateral internal thoracic artery (BITA) grafting after CABG is associated with improved long-term outcomes. We aimed to evaluate the impact of multivessel OPCAB with BITA grafting for complete revascularization on postoperative and long-term outcomes in patients with low LV ejection fraction (EF). We included 121 patients with EF ≤ 30.0% who underwent isolated multivessel OPCAB (average LVEF, 24.8%) between April 2007 and December 2019. Sixty-six patients received BITA grafts, while 55 had single internal thoracic artery (SITA) grafts. We conducted multivariate analyses to examine the correlation between perioperative data and late mortality rate. The early mortality rate was 1.65%. After excluding in-hospital mortality cases, we performed long-term follow-up of 119 patients. Early postoperative echocardiography showed significant LVEF improvement in 89 (75.2%) patients. However, LVEF remained ≤ 30.0% in 30 (24.8%) patients. We recorded 15 and 30 cases of cardiac death and cardiac events, respectively, during the long-term follow-up period. Postoperative LVEF ≤ 30.0% (P < 0.01) and no use of BITA grafting (P = 0.03) were significant predictors of cardiac death and events; moreover, hemodialysis was a significant predictor of all-cause mortality rather than cardiac death. Multivessel OPCAB in patients with severe LV dysfunction was associated with acceptable in-hospital mortality and early postoperative improvement in LV function. Additionally, OPCAB with BITA grafting may provide long-term benefits with respect to cardiac death and events. However, the long-term benefits were significantly limited in patients without early postoperative improvement in LV function and patients with chronic hemodialysis.Clinical registration number: 5590 (14/5/2020 Tokyo Women's Medical University).

Randomized comparison of HARVesting the Left Internal Thoracic Artery in a skeletonized versus pedicled technique: the HARVITA trial-study protocol

Latest research has indicated a potential adverse effect on graft patency rates and clinical outcomes with skeletonizing the left internal thoracic artery. We aim to provide a prospective, randomized, multicentre trial to compare skeletonized versus pedicled harvesting technique of left internal thoracic artery concerning graft patency rates and patient survival. A total of 1350 patients will be randomized to either skeletonized or pedicled harvesting technique and undergo surgical revascularization. Follow-up will be performed at 30 days, 1 year, 2 years and 5 years after surgery. The primary outcome will be death or left internal thoracic artery graft occlusion in coronary computed tomography angiography or invasive angiography within 2 years (+/- 3 months) after surgery. The secondary outcome will be major adverse cardiac events (composite outcome of all-cause death, myocardial infarction and repeated revascularization) within 1 year, 2 years and 5 years after surgery. The primary end point will be compared in the modified intention-to-treat population between the two treatment groups using Kaplan-Meier graphs, together with log-rank testing. Hereby, we present the study protocol of the first adequately powered prospective, randomized, multicentre trial which compares skeletonized and pedicled harvesting technique of left internal thoracic artery regarding graft patency rates and patient survival.

Expert systematic review on the choice of conduits for coronary artery bypass grafting: endorsed by the European Association for Cardio-Thoracic Surgery (EACTS) and The Society of Thoracic Surgeons (STS)

PREAMBLE

The finalized document was endorsed by the EACTS Council and STS Executive Committee before being simultaneously published in the European Journal of Cardio-thoracic Surgery (EJCTS) and The Annals of Thoracic Surgery (The Annals) and the Journal of Thoracic and Cardiovascular Surgery (JTCVS).

Up-to-Date, Skeletonized or Pedicle Bilateral Internal Mammary Artery; Does It Matter?

PURPOSE

In this article, we reported on the up-to-date literature regarding skeletonized bilateral internal mammary artery (BIMA) flow and the effect on sternal perfusion. We also reviewed the pros and cons of the skeletonization technique versus the conventional pedicle technique for harvesting the BIMA.

METHODS

We performed an up-to-date review using the PubMed database, with a specific focus on the contemporary published literature.

RESULTS

BIMA skeletonization can preserve the sternal microcirculation, minimize tissue damage, and maintain blood supply to the chest wall at the tissue level. This effect is also apparent in diabetics. Deep sternal wound infection (DSWI) rates are significantly less with skeletonization versus the conventional pedicle technique and are comparable to single internal mammary artery harvesting.

CONCLUSIONS

Contemporary large-scale studies demonstrate that skeletonization of the BIMA increases conduit length, provides superior flow, reduces the incidence of DSWIs, and improves late survival. Hopefully, this review will increase awareness of the compelling evidence in favor of using skeletonized internal mammary arteries and stimulate increased uptake of BIMA revascularization surgery.

Skeletonized or Pedicled Harvesting of Left Internal Mammary Artery: A Systematic Review and Meta-analysis

We sought to compare clinical outcomes in skeletonized versus pedicled left internal mammary artery (LIMA) grafts in elective coronary artery bypass grafting through a systematic review and meta-analysis. A comprehensive electronic literature search of PubMed, Ovid, Embase, and Scopus was conducted from inception to January 2020. Only short-term (30 days) studies which compared both techniques have been included in our analysis. Primary outcomes were post anastomosis flow rate and sternal wound infection rate (SWI); secondary outcomes were conduit length, acute myocardial infarction and 30-day mortality. Thirteen articles with a total of 6222 patients met the inclusion criteria. Except for the prevalence of diabetes mellitus being significantly lower in the skeletonized cohort (odds ratio [OR] 0.77 95% confidence interval [CI] [0.61, 0.97], P = 0.03), there were no differences in the preoperative demographics between the 2 groups. The skeletonized LIMA conduit was significantly longer when compared to the pedicled conduit (weighted mean difference -2.64 cm 95% CI [-3.71, -1.56], P < 0.0001). SWI rates were not significantly different in the skeletonized versus pedicled LIMA group (OR 0.71 95% CI [0.47, 1.06], P = 0.10). New onset of acute myocardial infarction and 30-day mortality rate was similar in the 2 groups (OR 1.04 and 0.97, respectively, P > 0.05 in both). The postanastomoses flow rate was higher in skeletonized LIMA (Weighted Mean Difference -11.51 mL/min 95% CI [-20.54, -2.49], P < 0.01). Harvesting the LIMA using the skeletonized technique is associated with higher postanastomosis flow rates and longer conduit lengths; with no difference in SWI and mortality rates when compared to the pedicled technique. We suggest that this technique should be adopted, particularly for BITA harvesting. However, further research is needed to provide clearer indications for both methods.

Effect of Skeletonization of Bilateral Internal Thoracic Arteries on Deep Sternal Wound Infections

BACKGROUND

Bilateral internal thoracic arteries (BITA) coronary bypass grafting may improve long-term outcomes but is associated with increased deep sternal wound infections (DSWIs). We analyzed whether BITA skeletonization impacts DSWIs and operative mortality (OM) using The Society of Thoracic Surgeons Adult Cardiac Surgery Database.

METHODS

Primary, isolated, nonemergent/nonsalvage BITA patients (July 2017 to December 2018) in The Society of Thoracic Surgeons Adult Cardiac Surgery Database were divided into groups based on BITA harvesting technique: both skeletonized (ssBITA) and ≥1 nonskeletonized (Non-ssBITA). DSWI and OM observed-to-expected (O/E) ratios were compared using The Society of Thoracic Surgeons Perioperative Risk Models. ssBITA versus Non-ssBITA DSWI and OM adjusted odds ratios were calculated by multivariable logistic regression and corroborated by propensity score matching.

RESULTS

We analyzed 11,269 patients (42.8% ssBITA, 57.2% Non-ssBITA, 770 hospitals, 1448 surgeons). The ssBITA group had a higher incidence of comorbidities and off-pump surgery. Overall incidences of DSWIs and OM were 0.98% (O/E ratio, 5.1) and 1.72% (O/E ratio, 1.4), respectively, and were 28% (P = .129) and 23% (P = .096) lower in ssBITA. The DSWI O/E ratio was highest (5.9) in Non-ssBITA and lowest in ss-BITA (4.1). After multivariable adjustment, ssBITA was associated with a decreased risk of DSWIs (adjusted odds ratio, 0.66; 95% confidence interval, 0.44-1.00; P = .05), with no difference in OM. These results were confirmed among 3884 propensity score-matched pairs. DSWIs increased sharply with increasing number of risk factors for DSWIs regardless of harvesting technique, with a trend for higher DSWIs among Non-ssBITA for all risk categories.

CONCLUSIONS

The observed high O/E ratio indicates that BITA grafting is associated with increased risk of DSWIs. Risk-adjusted DSWI rate and a lower O/E ratio in ssBITA support the protective role of skeletonization.

Trials Comparing Percutaneous And Surgical Myocardial Revascularization: A Review

INTRODUCTION

Ischemic heart diseases are the major leading cause of death worldwide. Revascularization procedures dramatically reduced the overall risk for death related to acute coronary syndromes. Two kinds of myocardial revascularization can grossly be outlined: percutaneous coronary intervention (PCI) and surgical coronary artery bypass graft intervention (CABG). The net clinical benefit coming from these two kinds of procedures is still under debate.

METHODS

We have traced the state-of-the-art background about myocardial revascularization procedures by comparing the most important trials dealing with the evaluation of percutaneous interventions versus a surgical approach to coronary artery diseases.

RESULTS

Both PCI and CABG have become effective treatments for revascularization of patients suffering from advanced CAD. The advance in technology and procedural techniques made PCI an attractive and, to some extent, more reliable procedure in the context of CAD. However, there are still patients that cannot undergo PCI and have to be rather directed towards CABG.

CONCLUSION

CABG still remains the best strategy for the treatment of multiple vessel CAD due to improved results in term of survival and freedom from reintervention. Anyway, a systematic, multidisciplinary approach to revascularization is the fundamental behaviour to be chased in order to effectively help the patients in overcoming its diseases. The creation of the "heart team" seems to be a good option for the correct treatment of patients suffering from stable and unstable CAD.

The radial artery in coronary surgery, 2018

It is now 25 years since the radial artery (RA) was reintroduced in coronary surgery. It has evolved into being a significant coronary artery bypass conduit and ranks third in usage after the internal thoracic artery (ITA) and saphenous vein grafts (SVG). Its advantages are that it can be readily and efficiently harvested, is of good length and appropriate size for coronary artery bypass graft (CABG) surgery, is robust and easy to handle, and remains free of atheroma, and there is minimal wound morbidity. The RA must be used judiciously with attention to spasm prophylaxis because of its muscular wall, and by avoiding competitive flow. Its patency is equivalent to the ITAs when placed to similar coronary territories and under similar conditions (stenosis, size, quality) and RA patencies are always superior to those of SVG in both observational and randomized studies-88-90% versus 50-60% at 10 years, and 80-87% versus 25-40% at 20 years. Its use and excellent patencies result in survival results equivalent to bilateral internal thoracic artery (BITA) grafting and always superior to left internal thoracic artery (LITA) +SVG. Typical radial artery multiarterial bypass grafting (RA-MABG) 10-year survivals are 80-90% versus 70-80% for LITA-SVG. In general, for every 100 patients undergoing CABG, 10 more patients will be alive at 10 years post-operatively. The RA also is important in achieving total arterial revascularization, and several reports indicate a further survival advantage for patients having three arterial grafts over two. The RAs are especially useful in diabetic, morbidly obese patients, those with conduit shortage, and leg pathology, and in coronary reoperations. Although the RA has equivalent patencies to the right internal thoracic artery (RITA), it is much more versatile. RAs that have been instrumented by angiography or percutaneous coronary intervention should be avoided. The radial artery has proved to be an excellent arterial conduit, is equivalent to but more versatile than the RITA, and is always superior to SVG. Its use should be part of every coronary surgeon's skill set.

The risk of mediastinitis and deep sternal wound infections with single and bilateral, pedicled and skeletonized internal thoracic arteries

Bilateral internal thoracic artery (BITA) grafting may prolong survival in coronary artery bypass graft (CABG) patients, but its use has been curtailed due to concerns of deep sternal wound infections (DSWI) resulting in mediastinitis. This article examines the association of single internal thoracic artery (SITA) and BITA grafting and the role of harvesting techniques with the development of DSWI in CABG patients. The development of DSWI following BITA grafting is multifactorial and is independent of the harvesting technique.

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.

Development and Validation of a Stratification Tool for Predicting Risk of Deep Sternal Wound Infection after Coronary Artery Bypass Grafting at a Brazilian Hospital

Objective

Deep sternal wound infection following coronary artery bypass grafting is a serious complication associated with significant morbidity and mortality. Despite the substantial impact of deep sternal wound infection, there is a lack of specific risk stratification tools to predict this complication after coronary artery bypass grafting. This study was undertaken to develop a specific prognostic scoring system for the development of deep sternal wound infection that could risk-stratify patients undergoing coronary artery bypass grafting and be applied right after the surgical procedure.

Methods

Between March 2007 and August 2016, continuous, prospective surveillance data on deep sternal wound infection and a set of 27 variables of 1500 patients were collected. Using binary logistic regression analysis, we identified independent predictors of deep sternal wound infection. Initially we developed a predictive model in a subset of 500 patients. Dataset was expanded to other 1000 consecutive cases and a final model and risk score were derived. Calibration of the scores was performed using the Hosmer-Lemeshow test.

Results

The model had area under Receiver Operating Characteristic (ROC) curve of 0.729 (0.821 for preliminary dataset). Baseline risk score incorporated independent predictors of deep sternal wound infection: obesity (P=0.046; OR 2.58; 95% CI 1.11-6.68), diabetes (P=0.046; OR 2.61; 95% CI 1.12-6.63), smoking (P=0.008; OR 2.10; 95% CI 1.12-4.67), pedicled internal thoracic artery (P=0.012; OR 5.11; 95% CI 1.42-18.40), and on-pump coronary artery bypass grafting (P=0.042; OR 2.20; 95% CI 1.13-5.81). A risk stratification system was, then, developed.

Conclusion

This tool effectively predicts deep sternal wound infection risk at our center and may help with risk stratification in relation to public reporting and targeted prevention strategies in patients undergoing coronary artery bypass grafting.

[Coronary artery bypass graft surgery with bilateral internal mammary artery. Short-term results]

INTRODUCTION

Coronary artery bypass graft (CABG) surgery remains the reference standard in the treatment of multivessel coronary disease. Several studies have shown that CABG with bilateral internal mammary arteries (BIMA) has better results in long-term survival.

METHODOLOGY

A retrospective study was conducted on CABG surgeries with BIMA from January 2012 to December 2015 in the National Cardiovascular Institute, INCOR, EsSalud, Peru. The objectives were to determine the mortality and major cardiovascular events at 30 days follow-up.

RESULTS

Of the 36 patients subjected to CABG surgery with BIMA, the 30-day mortality was 0%, with major cardiovascular events occurring in 5.56% of patients (Stroke 0%, postoperative myocardial infarction 5.56%, need of new coronary intervention 0%). The incidence of mediastinitis and/or sternal reconstruction was 0%. Superficial wound infection was observed in 7 patients, with there being no significant difference between diabetics and non-diabetics (25% vs. 16.66%, OR=3.3, P=.88), or between patients with or without overweight (19.23% vs. 20%, respectively, OR=.95; 95% CI, P=.68).

CONCLUSIONS

CABG surgery with BIMA is a safe procedure, with low rates of mortality and major cardiovascular events in the short-term.

Total Arterial Revascularization: Bypassing Antiquated Notions to Better Alternatives for Coronary Artery Disease

Total arterial revascularization is the leading trend in coronary artery bypass grafting (CABG) for the treatment of coronary artery disease (CAD). Adding to its superiority to vein conduits, arteries allow for a high degree of versatility and long-term patency, while minimizing the need for reintervention. This is especially important for patients with multi-vessel coronary artery disease, as well as young patients. However, arterial revascularization has come a long way before being widely appreciated, with some yet unresolved debates, and advances that never cease to impress. In this review, we discuss the evolution of this surgical technique and its clinical success, as well as its most conspicuous limitations in light of accumulated published date from decades of experience.

Potential Risk Factors for Surgical Site Infection after Isolated Coronary Artery Bypass Grafting in a Bahrain Cardiac Centre: A Retrospective, Case-Controlled Study

Objective:

The purposes of this study were to determine the incidence of surgical site infections (SSI) and associated risk factors in patients undergoing isolated coronary artery bypass grafting (CABG) in our cardiac center during a 2-year period.

Materials and Methods:

Retrospective case-control analysis for 80 patients who underwent isolated cardiac surgery CABG. These patients were divided into the SSI study group (n = 40) and the noninfected control group (n = 40). Eight potential perioperative risk variables were compared between the two groups using univariate logistic regression analysis.

Results:

Univariate analysis was carried out for eight potential risk factors. The risk factors found to be significant were: Impaired estimated glomerular filtration rate (P = 0.011) and impaired left ventricular ejection fraction (P = 0.015). However, Factors found to have no significant influence on the incidence of SSIs were: Perioperative length of hospital stay (days), urgency of surgery, use of bilateral internal mammary artery (BIMA) grafting, prolonged cardiopulmonary bypass duration, elevated body mass index.

Conclusions:

Patients with comorbidities of impaired renal function and/or impaired left ventricular systolic function are at high risk of developing SSI. There appears to be a relationship between SSIs in CABG patients and impaired renal or LV function (low ejection fraction). CABG with BIMA grafting could be performed safely even in diabetics. Future studies should consider further scrutiny of these and other factors in relation to SSIs in a larger surgical population.

The current status of multi-arterial off-pump coronary artery bypass grafting

PURPOSE

Off-pump coronary artery bypass surgery has not become widespread because of its technical difficulty. However, especially in Asia, pioneer surgeons continue with efforts to develop the off-pump technique.

METHOD

By reviewing past studies, mainly retrospective single-center reports, an up-to-date profile of off-pump surgery was assembled.

RESULTS

Many of the past randomized trials failed to demonstrate the advantages of off-pump surgery. Although many of these were single-center retrospective studies, the data presented, mostly from world-famous surgeons, show that off-pump surgery does have advantages in high-risk patients and results in reduced rates of postoperative morbidity and equal rates of mortality in both the short- and long terms. Moreover, almost all experienced off-pump surgeons noted the benefit of multiple uses of arterial grafts, skeletonization harvesting of arterial conduits and the aorta no-touch technique.

CONCLUSION

The off-pump procedure has not become a standard technique performed by the average surgeon in daily practice. However, off-pump surgery will continue to provide a significant benefit to high-risk patients with coronary disease.

Deep sternal wound infection after cardiac surgery: Evidences and controversies

Despite many advances in prevention and perioperative care, deep sternal wound infection (DSWI) remains a pressing concern in cardiac surgery, with a still relevant incidence and with a considerable impact on in-hospital mortality and also on mid- and long-term survival. The permanent high impact of this complication is partially related to the increasing proportion of patients at high-risk for infection, as well as to the many patient and surgical risk factors involved in the pathogenesis of DSWI. The prophylactic antibiotic therapy is one of the most important tools in the prevention of DSWI. However, the choice of antibiotic, the dose, the duration, the adequate levels in serum and tissue, and the timing of antimicrobial prophylaxis are still controversial. The treatment of DSWI ranges from surgical revision with primary closure to surgical revision with open dressings or closed irrigation, from reconstruction with soft tissue flaps to negative pressure wound therapy (NPWT). However, to date, there have been no accepted recommendations regarding the best management of DSWI. Emerging evidence in the literature has validated the efficacy and safety of NPWT either as a single-line therapy, or as a “bridge” prior to final surgical closure. In conclusion, the careful control of patient and surgical risk factors - when possible, the proper antimicrobial prophylaxis, and the choice of validated techniques of treatment could contribute to keep DSWIs at a minimal rate.

Incidence of Deep Sternal Wound Infection in Diabetic Patients Undergoing Off-Pump Skeletonized Internal Thoracic Artery Grafting

OBJECTIVES

To evaluate the impact of skeletonized bilateral or single internal thoracic artery (ITA) grafting on the risk of deep sternal wound infection (DSWI) in diabetic patients undergoing off-pump coronary artery bypass grafting (OPCAB).

MATERIALS AND METHODS

A total of 803 diabetic patients undergoing OPCAB surgery from January 2010 to December 2014 were enrolled into this study and assigned to the pSITA group (patients undergoing pedicled single ITA grafting, n = 362), the sSITA group (skeletonized single ITA grafting, n = 295), or the sBITA group (skeletonized bilateral ITA grafting, n = 146). The primary end point was the diagnosis of a DSWI.

RESULTS

Eighteen patients developed postoperative DSWI, with an incidence of 2.2%. Patients in the sSITA group had a significantly lower incidence of DSWI than those in the pSITA group (1.0 vs. 3.6%, p = 0.0408). In multivariate logistic regression analysis, the risk of DSWI in the sSITA group was 0.41 times that in the pSITA group.

CONCLUSIONS

sSITA grafting lowered the risk of DSWI in diabetic patients undergoing OPCAB surgery compared to pSITA grafting. Multicenter clinical trials involving larger sample sizes are needed to determine the merit of pSITA grafting in reducing the risk of DSWI following OPCAB surgery.

Total arterial off-pump coronary artery bypass grafting was not associated with inferior outcomes for diabetic when compared with non-diabetic patients

OBJECTIVES

Diabetes mellitus is a strong risk factor that worsens the clinical outcome of patients undergoing coronary artery bypass grafting (CABG). With the development of the off-pump CABG technique, there is a current trend in revascularization strategies towards in situ all-arterial grafting. We were interested in whether total arterial off-pump CABG could improve the outcome for diabetic patients.

METHODS

From January 2002 to December 2013, a total of 1064 patients underwent off-pump CABG at our institution, with total arterial reconstruction carried out in 775 cases. Of the 775 patients, 436 had diabetes (DM) and 339 did not (nDM). After propensity score matching, 301 cases from each group were successfully matched.

RESULTS

All procedures were performed via the off-pump technique without conversion to on-pump. Four patients in the DM group and 1 in the nDM group died in hospital. Multivariate analysis revealed that chronic pulmonary disease [odds ratio (OR) 7.04, P = 0.036] and low (<40%) ejection fraction (OR 11.3, P = 0.009) are independent risk factors for hospital death, and advanced age for deep sternal infection (OR 1.07, P = 0.04). Follow-up was completed in 97.7% of the patients to a maximum of 11.9 years. The rate of 10-year freedom from all-cause mortality was 84.2% in the DM and 74.3% in the nDM group (P = 0.45). The corresponding rates for major adverse cardiac event were 93.3 and 86.9% (P = 0.09). Multivariate Cox regression analysis revealed chronic renal failure, older age, cerebrovascular accident, low ejection fraction and urgency as significant predictors of late death. Diabetes was not associated with any long- or short-term outcome.

CONCLUSIONS

Total arterial off-pump CABG using skeletonization technique can provide similar clinical outcome for diabetic patients in the long as well as in the short term as that for non-diabetic patients.

[Cold-plasma sternotomy and postoperative sternal consolidation]

MATERIAL AND METHODS

It is presented the results of cold-plasma sternotome application in 16 patients. Efficiency of this technique, its effect on sternal reparation as well as on the incidence of early and remote (4-5 months) postoperative wound complications were analyzed. Control group included 19 patients who underwent conventional sternotomy using high-temperature electrocoagulation and medical wax for hemostasis. Risk factors for sternal infection were comparable in both groups. Physical examination and computed tomography were performed in all patients to access incidence of complications and degree of bone tissueconsolidation respectively in postoperative period.

RESULTS

It is shown that cold-plasma sternotomy leads to early inflammation resolution in oversplitting area and to reduction of wound complications incidence.

Off-pump Skeletonized Versus Pedicled Left Internal Mammary Artery Grafting: Mid-term Results

BACKGROUND

Skeletonization of the internal mammary artery for single left internal mammary artery (LIMA) use remains controversial. We sought to elucidate the effect of different harvesting techniques applied in single LIMA grafting.

METHOD

Between January 2006 and January 2012, 982 patients undergoing off-pump coronary artery bypass with pedicled LIMA conduits (P Group) and 928 patients undergoing the same operation with skeletonized LIMA conduits (S Group) were enrolled. The length and blood flow of the conduits, and in-hospital and mid-term outcomes with one-year postoperative graft angiographic results were analyzed and compared between groups.

RESULTS

Twenty-five (2.7%) patients in the S group died in hospital, compared with 26 (2.6%) in the P group, with similar rates of sternal wound infection, chest wall pain, and low-output syndrome. Although the length and blood flow of conduits were increased in the S Group, postoperative conduit patency was similar between groups (p = 0.470). During a median follow-up of 32.2 months, the groups showed similar total survival (88.3 ± 3.2%, S Group; 85.5 ± 2.0%, P Group; p = 0.118) and cardiac event-free survival (82.7 ± 3.3%, S Group; 80.3 ± 2.0%; P Group; p = 0.129), with similar postoperative complications.

CONCLUSIONS

Skeletonization of single LIMA has no extra benefit in early or mid-term outcomes, suggesting no advantage over the pedicled technique.

Assessment of vacuum-assisted closure therapy on the wound healing process in cardiac surgery

Postoperative deep sternal wound infection (DSWI) is a serious complication in cardiac surgery (1-5% of patients) with high mortality and morbidity rates. Vacuum-assisted closure (VAC) therapy has shown promising results in terms of wound healing process, postoperative hospital length of stay and lower in-hospital costs. The aim of our retrospective study is to report the outcome of patients with DSWI treated with VAC therapy and to assess the effect of contributory risk factors. Data of 52 patients who have been treated with VAC therapy in a single institution (study period: September 2003-March 2012) were collected electronically through PAtient Tracking System PATS and statistically analysed using SPSS version 20. Of the 52 patients (35 M: 17 F), 88·5% (n = 46) were solely treated with VAC therapy and 11·5% (n = 6) had additional plastic surgical intervention. Follow-up was complete (mean 33·8 months) with an overall mortality rate of 26·9% (n = 14) of whom 50% (n = 7) died in hospital. No death was related to VAC complications. Patient outcomes were affected by pre-operative, intra-operative and postoperative risk factors. Logistic EUROscore, postoperative hospital length of stay, advanced age, chronic obstructive pulmonary disease (COPD) and long-term corticosteroid treatment appear to be significant contributing factors in the long-term survival of patients treated with VAC therapy.

Similar outcome in insulin-dependent and noninsulin-dependent diabetic patients after off-pump coronary artery bypass grafting with multiple skeletonized arterial conduits

BACKGROUND

We were interested in whether current multiarterial off-pump coronary artery bypass graft surgery can improve the clinical outcome for insulin-dependent diabetes mellitus patients.

METHODS

Between January 2002 and December 2013, 1,064 consecutive patients underwent isolated off-pump coronary artery bypass surgery at our hospital; 551 of these patients had diabetes. Of these 551 patients, 166 had insulin-dependent diabetes (IDM) and the remaining 385 had noninsulin-dependent diabetes (NIDM). The propensity score was calculated to achieve one-to-two matching sets (IDM 143 versus NIDM 286).

RESULTS

Ten patients (3.5%) in the NIDM group and 2 patients (1.4%) in the IDM group died in hospital (p = 0.18). Insulin dependency was not an independent risk factor for any early death or major complications. Follow-up was complete for 96.5% of the patients, with a mean follow-up of 4.6 ± 3.8 years. Overall survival rate at 10 years was 76.3% for the NIDM group and 73.1% for the IDM group (p = 0.79). The rate of 10-year actuarial freedom from major adverse cardiac events was 89.6% in the NIDM group and 86.3% in the IDM group (p = 0.72). Multivariate Cox proportional hazard regression analysis revealed that female sex, congestive heart failure, previous myocardial infarction, lower ejection fraction, and at least one major complication were independent risk factors for combined cardiac events. Insulin dependency did not affect any outcome in the long term.

CONCLUSIONS

Early and long-term outcomes after off-pump skeletonized multiarterial coronary artery bypass graft surgery were similar among the IDM and NIDM patients.

Comparative analysis of the patency of the internal thoracic artery in the CABG of left anterior descending artery: 6-month postoperative coronary CT angiography evaluation

Objective

To assess the patency of the pedicled right internal thoracic artery with an anteroaortic course and compare it to the patency of the left internal thoracic artery , in anastomosis to the left anterior descending artery in coronary artery bypass grafting by using coronary CT angiography at 6 months postoperatively.

Methods

Between December 2008 and December 2011, 100 patients were selected to undergo a prospective coronary artery bypass grafting procedure without cardiopulmonary bypass. The patients were randomly divided by a computer-generated list into Group-1 (G-1) and Group-2 (G-2), comprising 50 patients each, the technique used was known at the beginning of the surgery. In G-1, coronary artery bypass grafting was performed using the left internal thoracic artery for the left anterior descending and the free right internal thoracic artery for the circumflex, and in G-2, coronary artery bypass grafting was performed using the right internal thoracic artery pedicled to the left anterior descending and the left internal thoracic artery pedicled to the circumflex territory.

Results

The groups were similar with regard to the preoperative clinical data. A male predominance of 75.6% and 88% was observed in G-1 and G-2, respectively. Five patients migrated from G-1 to G-2 because of atheromatous disease in the ascending aorta. The average number of distal anastomoses was 3.48 (SD=0.72) in G-1 and 3.20 (SD=0.76) in G-2. Coronary CT angiography in 96 re-evaluated patients showed that all ITAs, right or left, used in situ for the left anterior descending were patent. There were no deaths in either group.

Conclusion

Coronary artery bypass grafting surgery involving anastomosis of the anteroaortic right internal thoracic artery to the left anterior descending artery has an outcome similar to that obtained using the left internal thoracic artery for the same coronary site.

Coronary artery disease and diabetes mellitus

Diabetes mellitus (DM) is a major risk factor for cardiovascular disease. Near-normal glycemic control does not reduce cardiovascular events. For many patients with 1- or 2-vessel coronary artery disease, there is little benefit from any revascularization procedure over optimal medical therapy. For multivessel coronary disease, randomized trials demonstrated the superiority of coronary artery bypass grafting over multivessel percutaneous coronary intervention in patients with treated DM. However, selection of the optimal myocardial revascularization strategy requires a multidisciplinary team approach ('heart team'). This review summarizes the current evidence regarding the effectiveness of various medical therapies and revascularization strategies in patients with DM.

Two questions on bilateral internal mammary artery usage

The use of a single internal mammary graft to the left anterior descending artery has been the gold standard in surgical coronary revascularization since its introduction. However, the take-up rate of use of bilateral internal mammary arteries has been slow despite emerging evidence. This has been partly due to the worry of postoperative complications, in particular, sternal wound complications. Skeletonization of the internal mammary has been proposed as a technique that can preserve the sternal microcirculation and therefore reduce this complication. In this article, we examine the evidence comparing the skeletonization technique versus the conventional pedicled technique for harvesting the internal mammary artery.

Total arterial coronary revascularization-patient selection, stenoses, conduits, targets

Graft patency determines prognosis in coronary artery bypass grafting (CABG). Numerous reports over the past 20 years have documented superior patencies and prognosis when multiple arterial grafts are used, yet less than 10% of CABG have multiple arterial grafts. Several conduits have been proposed, with varying degrees of success. Saphenous vein grafts (SVG) begin to fail with intimal hypertrophy and then atheroma after 5 years, with patency rates of 50% to 60% at 10 years, and <30% at 15 years. In contrast, left internal thoracic artery (LITA) patency is >95% at 10 years and >90% at 20 years. The radial artery is extremely versatile and can reach all territories, but is muscular and vulnerable to spasm and competitive flow. Similarly, the right gastroepiploic artery is also muscular, and is best suited to the posterior descending coronary artery, especially in reoperations and is also affected by competitive flow. In addition, bilateral internal thoracic artery grafting (BITA) grafts and total arterial revascularization (TACR) can be performed with identical perioperative mortality (1%) and perioperative morbidity to LITA + SVG. Importantly, survival is superior-85% to 90% at 10 years versus 75% to 80% respectively. BITA/TACR patients also suffer fewer late cardiac events and reoperations, with superior results for older patients, those requiring urgent surgery, diabetics, patients with renal dysfunction and in reoperations. Contraindications to BITA include obesity, insulin dependent diabetics, and severe chronic obstructive airways disease. As such, arterial grafts have better patencies and clinical results. BITA/TACR is often underutilized, but can be achieved in the majority of patients. Opportunities exist to enhance BITA/TACR use in CABG to the potential benefit of our patients.

Bilateral internal mammary arteries: evidence and technical considerations

Bilateral internal mammary artery (BIMA) grafts are used for coronary revascularisation by only a minority of surgeons, despite a growing body of evidence suggesting improved survival when compared to use of only one internal mammary artery with additional saphenous vein grafts. Herein we review the evidence supporting revascularisation with BIMA and suggest reasons why the majority of surgeons use only one internal mammary artery. We discuss technical considerations, various graft combinations and the use of BIMA to facilitate anaortic off-pump coronary artery bypass (OPCAB).

The history of arterial revascularization: from Kolesov to Tector and beyond

Coronary artery bypass grafting (CABG) is the one of the most effective revascularization strategies for patients with obstructive coronary artery disease. Total arterial revascularization using one or both internal thoracic and radial arteries has been shown to improve early outcomes and reduce long-term cardiovascular morbidity. Although CABG has evolved from an experimental procedure in the early 1900's to become one of the most commonly performed surgical procedures, there is still significant variation in grafting strategies amongst surgeons. We review the history and development of CABG with a particular emphasis on the early pioneers and the evolution of arterial grafting.

Skeletonized versus pedicled internal thoracic artery and risk of sternal wound infection after coronary bypass surgery: meta-analysis and meta-regression of 4817 patients

It is suggested that the internal thoracic artery (ITA) harvesting technique influences the incidence of sternal wound infection (SWI) after coronary artery bypass graft (CABG). To determine if there is any real difference between skeletonized vs pedicled ITA, we performed a meta-analysis to determine if there is any real difference between these two established techniques in terms of SWI. We performed a systematic review using MEDLINE, EMBASE, CENTRAL/CCTR, SciELO, LILACS, Google Scholar and reference lists of relevant articles to search for studies that compared the incidence of SWI after CABG between skeletonized vs pedicled ITA until June 2012. The principal summary measures were odds ratio (OR) with 95% confidence interval (CI) and P values (statistically significant when <0.05). The ORs were combined across studies using the weighted DerSimonian-Laird random effects model and weighted Mantel-Haenszel fixed effects. Meta-analysis, sensitivity analysis and meta-regression were completed using the software Comprehensive Meta-Analysis version 2 (Biostat, Inc., Englewood, NJ, USA). Twenty-two studies involving 4817 patients (2424 skeletonized; 2393 pedicled) met the eligibility criteria. There was no evidence for important heterogeneity of effects among the studies. The overall OR (95% CI) of SWI showed a statistically significant difference in favour of skeletonized ITA (fixed effect model: OR 0.443, 95% CI 0.323-0.608, P < 0.001; random effect model: OR 0.443, 95% CI 0.323-0.608, P < 0.001). In the sensitivity analysis, the difference in favour of skeletonized ITA was also observed in subgroups such as diabetic, bilateral ITA and diabetic with bilateral ITA; we also observed that there was a difference in the type of study, since non-randomized studies together demonstrated the benefit of skeletonized ITA in comparison with pedicled ITA, but the randomized studies together did not show this difference (although close to statistical significance and with the tendency to favour the skeletonized group). In meta-regression, we observed a statistically significant coefficient for SWI and proportion of diabetic patients (coefficient -0.02, 95% CI -0.03 to -0.01, P = 0.016). In conclusion, skeletonized ITA appears to reduce the incidence of postoperative SWI in comparison with pedicled ITA after CABG, with this effect being modulated by the presence of diabetes.

Simple adaptations of surgical technique to critically reduce the risk of postoperative sternal complications in patients receiving bilateral internal thoracic arteries

OBJECTIVES

Limited blood supply to the thoracic chest wall is a known risk factor for sternal wound complications after CABG. Therefore, bilateral internal thoracic arteries are still rarely utilized despite their proven superior graft patency. The aim of our study was to analyse whether modification of the surgical technique is able to limit the risk of sternal wound complications in patients receiving bilateral internal thoracic artery grafting.

METHODS

All 418 non-emergent CABG patients receiving bilateral internal thoracic artery CABG procedures (BITA) from January 2001 to January 2012 were analysed for sternal wound complications. Surgical technique together with known risk factors and relevant comorbidity were analysed for their effect on the occurrence of sternal wound complications by means of multivariate logistic regression analysis.

RESULTS

Sternal wound complications occurred in 25 patients (5.9%), with a sternal dehiscence rate of 2.4% (10 patients). In multivariate analysis, diabetes (odds ratio [OR]: 4.8, 95% CI: 1.9-11.7, P=0.001), but not obesity (OR: 1.6, 95% CI: 0.7-4.2, P=0.28) or chronic obstructive pulmonary disease (OR: 2.2, 95% CI: 0.87-5.6, P=0.1) was a relevant comorbid condition for sternal complications. Skeletonization of ITA grafts (OR: 0.17, 95% CI: 0.06-0.5, P=0.001) and the augmented use of sternal wires (OR: 0.24, 95% CI: 0.06-0.95, P=0.04) were highly effective in preventing sternal complications. The use of platelet-enriched-fibrin glue (PRF) sealant, however, was associated with more superficial sternal infections (OR: 3.7, 95% CI: 1.3-10.5, P=0.02).

CONCLUSIONS

Adjusted for common risk factors, skeletonization of BITA grafts together with augmented sternal wires is effective in preventing sternal complications. The use of PRF sealant, however, increased the risk for superficial wound complications.