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.

Superior Outcomes of Dual-Arterial Coronary Artery Bypass Grafting Are Maintained in the Veterans Health Administration.

INTRODUCTION: Controversy surrounds the long-term clinical benefit of coronary artery bypass grafting (CABG) using dual arterial grafts (DAGs) compared to single arterial grafts (SAGs). We investigated outcomes of DAG, using single internal thoracic artery and radial artery (DAG-RA) or bilateral internal thoracic artery grafts (DAG-BITA), compared to SAG, using the left internal thoracic artery and saphenous vein grafts, in the U.S. Veterans Health Administration (VA). METHODS: We conducted a cross-sectional study of U.S. Veterans undergoing isolated on-pump CABG between 2005 and 2015 at 44 VA medical centers. The primary composite outcome was first occurrence of a major adverse cardiac and cerebrovascular event (MACCE), comprised of death from any cause, myocardial infarction, stroke, or repeat revascularization. RESULTS: Among 25,969 Veterans undergoing isolated CABG, 1261 (4.9%) underwent DAG (66.8% DAG-RA and 33.2% DAG-BITA). Over a 5-y follow-up, DAG was associated with lower rates of all-cause death (adjusted hazard ratio [AHR] 0.70, 95% confidence interval [CI] 0.58-0.85), MACCE (AHR 0.80, 95% CI 0.71-0.91), and stroke (AHR 0.74, 95% CI 0.57-0.96) versus SAG. DAG-BITA was associated with lower rates of all-cause death (AHR 0.52, 95% CI 0.35-0.77) and MACCE (AHR 0.66, 95% CI 0.51-0.84) than SAG, while DAG-RA was associated with lower rates of all-cause death (AHR 0.79, 95% CI 0.64-0.99). CONCLUSIONS: In the VA, DAG was associated with improved long-term MACCE outcomes compared to SAG. These results suggest that the practice of DAG in the VA benefits Veterans and should be promoted further.

Endovascular Embolization for Idiopathic Serial Right Internal Mammary Artery Aneurysms.

CLINICAL IMAPCT: This article showed images of a patient with idiopathic serial right internal mammary artery true aneurysms treated by endovascular embolization, which is a rare diagnosis and should be considered in differential diagnosis of paratracheal mass.

Differential Suppressive Effects of Rho Kinase Inhibitor Fasudil on Serotonin- and Noradrenaline-Induced Contractions of Human Internal Thoracic Arteries and Saphenous Veins.

Rho kinase inhibitor fasudil exerts therapeutic effects against vasospasms. In this study, we aimed to compare its suppressive effects on serotonin (5-HT)- and noradrenaline (NAd)-induced contractions of human endothelium-denuded internal thoracic arteries (ITAs) and saphenous veins (SVs). NAd and 5-HT induced concentration-dependent contractions in both ITAs and SVs. However, fasudil (3 µmol/L) pretreatment decreased these constrictor-induced contractions in both ITAs and SVs. Fasudil exerted similar inhibitory effects on 5-HT and NAd in ITAs. However, in SVs, fasudil exerted stronger inhibitory effects on NAd-induced contractions than on 5-HT-induced contractions. Therefore, inhibitory effects of fasudil on 5-HT-induced contractions were stronger in ITAs than in SVs. Overall, these results suggest that Rho kinases exert different effects on the two vasoconstrictors in SVs, but not in ITAs, thus explaining their different graft patencies.

Internal thoracic artery as a growing conduit for pulmonary shunt.

Studies suggest the internal thoracic artery as a shunt option due to its growth potential. However, long-term data are lacking. Here, a patient with a failing single ventricle shunt had an enlarged internal thoracic artery. We followed the patient for 12 years after converting this artery into a Blalock-Taussig shunt, analysing its growth to assess its effectiveness.

Mirror, Mirror on the Wall; He Had a "Bypass" After All!

How to cite this article: Magoon R, Jose J, Kumar M. Mirror, Mirror on the Wall; He Had a "Bypass" After All! Indian J Crit Care Med 2024;28(7):706-707.

Author Response: Mirror, Mirror on the Wall; He Had a "Bypass" After All!

How to cite this article: Shukla MP. Author Response: Mirror, Mirror on the Wall; He Had a "Bypass" After All! Indian J Crit Care Med 2024;28(7):708.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines.

AIM: The executive summary of the American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions coronary artery revascularization guideline provides the top 10 items readers should know about the guideline. In the full guideline, the recommendations replace the 2011 coronary artery bypass graft surgery guideline and the 2011 and 2015 percutaneous coronary intervention guidelines. This summary offers a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization, as well as the supporting documentation to encourage their use. METHODS: A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered. Structure: Recommendations from the earlier percutaneous coronary intervention and coronary artery bypass graft surgery guidelines have been updated with new evidence to guide clinicians in caring for patients undergoing coronary revascularization. This summary includes recommendations, tables, and figures from the full guideline that relate to the top 10 take-home messages. The reader is referred to the full guideline for graphical flow charts, supportive text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in the development of this guideline.

Perioperative Safety of Bilateral Internal Thoracic Artery Coronary Bypass in Elderly.

Background: The benefits of utilizing internal thoracic arteries (ITAs) in coronary bypass surgery are well-known. However, the safety of this practice in elderly patients needs to be proven. Methods: We studied all patients who are 75 years of age and older, who received at least one ITA graft while undergoing isolated, conventional (median sternotomy) coronary artery bypass graft surgery (CABG) between Jan 1st 2002 and Dec 31st 2020 (19 years). Emergent surgeries were excluded. Propensity score matching was used to reduce the patient selection effect. Study outcomes were 30-days mortality, and two sets of dependent intraoperative parameters and postoperative parameters. Results: A total of 1855 patients undergoing CABG was included, of which 1114 received a single left (s)ITA and 741 received combined left and right (d)ITA grafts. 519 pairs were matched. The decision for sITA or dITA was made individually. Thirty-days mortality was low and similar in both groups (sITA 3.3%; dITA 2.9%, p = 0.859). The incidence of sternal wound healing disorder was higher after dITA (3.3 vs 6.9%; p < 0.011), which had also a longer skin-to-skin operative time (181 vs 205 min; p < 0.0001). Re-thoracotomy rates were similar (4.6 vs 6.2%; p = 0.340). There were no significant differences in other secondary parameters. Conclusions: harvesting both ITAs in elderly patients is safe and feasible. However, it increases the risk of sternal wound healing disorders. Long term benefit still needs to be proven.

Conduits and Strategies for Arterial Revascularization in CABG.

Ischemic heart disease is the leading cause of death in the United States. Depending on the severity of the coronary artery disease, treatment options include percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). Although CABG has been performed since the 1970s, there is still debate onwhich conduit to use after the left internal thoracic artery. Currently, national registries report the left internal thoracic artery and the saphenous vein as the most commonly used conduits in CABG, while other arterial grafts, such as the radial artery, represent a minority, even though the current evidence suggests potential benefits of these arterial conduits. In this review, we aimed to describe the different types of arterial conduits used for CABG and summarize the evidence behind their use.

CT angiography of non-aortic thoracic arterial trauma.

While aortic injury is the most commonly cited thoracic arterial injury, non-aortic arterial injuries represent an uncommon but significant source of morbidity and mortality in blunt and penetrating thoracic trauma patients. Knowledge of the spectrum of vascular injury and anatomic considerations that dictate patterns of associated thoracic hemorrhage will assist the radiologist in the accurate and efficient diagnosis of these injuries. This article provides a review of anatomy, pertinent clinical exam and CT angiography findings, as well as therapeutic options for non-aortic thoracic arterial trauma.

Multi-Omics Profiling of Human Endothelial Cells from the Coronary Artery and Internal Thoracic Artery Reveals Molecular but Not Functional Heterogeneity.

Major adverse cardiovascular events occurring upon coronary artery bypass graft surgery are typically accompanied by endothelial dysfunction. Total arterial revascularisation, which employs both left and right internal thoracic arteries instead of the saphenous vein to create a bypass, is associated with better mid- and long-term outcomes. We suggested that molecular profiles of human coronary artery endothelial cells (HCAECs) and human internal mammary artery endothelial cells (HITAECs) are coherent in terms of transcriptomic and proteomic signatures, which were then investigated by RNA sequencing and ultra-high performance liquid chromatography-mass spectrometry, respectively. Both HCAECs and HITAECs overexpressed molecules responsible for the synthesis of extracellular matrix (ECM) components, basement membrane assembly, cell-ECM adhesion, organisation of intercellular junctions, and secretion of extracellular vesicles. HCAECs were characterised by higher enrichment with molecular signatures of basement membrane construction, collagen biosynthesis and folding, and formation of intercellular junctions, whilst HITAECs were notable for augmented pro-inflammatory signaling, intensive synthesis of proteins and nitrogen compounds, and enhanced ribosome biogenesis. Despite HCAECs and HITAECs showing a certain degree of molecular heterogeneity, no specific markers at the protein level have been identified. Coherence of differentially expressed molecular categories in HCAECs and HITAECs suggests synergistic interactions between these ECs in a bypass surgery scenario.

Impact of diabetes mellitus on long-term clinical and graft outcomes after off-pump coronary artery bypass grafting with pure bilateral skeletonized internal thoracic artery grafts.

BACKGROUND: The effect of diabetes mellitus (DM) on the long-term outcomes of coronary artery bypass graft (CABG) remained debatable and various strategies exist for CABG; hence, clarifying the effects of DM on CABG outcomes is difficult. The current study aimed to evaluate the effect of DM on clinical and graft-related outcomes after CABG with bilateral internal thoracic artery (BITA) grafts. METHODS: From January 2001 to December 2017, 3395 patients who underwent off-pump CABG (OPCAB) with BITA grafts were enrolled. The study population was stratified according to preoperative DM. The primary endpoint was cardiac death and the secondary endpoints were myocardial infarction (MI), revascularization, graft failure, stroke, postoperative wound infection, and a composite endpoint of cardiac death, MI, and revascularization. Multiple sensitivity analyses, including Cox proportional hazard regression and propensity-score matching analyses, were performed to adjust baseline differences. RESULTS: After CABG, the DM group showed similar rates of cardiac death, MI, or revascularization and lower rates of graft failure at 10 years (DM vs. non-DM, 19.0% vs. 24.3%, hazard ratio [HR] 0.711, 95% confidence interval [CI] 0.549-0.925; P = 0.009) compared to the non-DM group. These findings were consistent after multiple sensitivity analyses. In the subgroup analysis, the well-controlled DM group, which is defined as preoperative hemoglobin A1c (HbA1c) of < 7%, showed lower postoperative wound infection rates (well-controlled DM vs. poorly controlled DM, 3.7% vs. 7.3%, HR 0.411, 95% CI 0.225-0.751; P = 0.004) compared to the poorly controlled DM group, which was consistent after propensity-score matched analysis. CONCLUSIONS: OPCAB with BITA grafts showed excellent and comparable long-term clinical outcomes in patients with and without DM. DM might have a protective effect on competition and graft failure of ITA. Strict preoperative hyperglycemia control with target HbA1c of < 7% might reduce postoperative wound infection and facilitate the use of BITA in CABG.

Is it safe to perform total arterial grafting in elderly patients lacking vein grafts? A single surgeon comparison.

OBJECTIVES: The results of coronary artery bypass graft (CABG) surgery with total arterial revascularisation (TA-CABG) in elderly patients, who may have insufficient vein graft material for conventional CABG (CO-CABG), have not been fully established. We therefore sought to compare the short- and long-term outcomes of patients >70 years old undergoing CO-CABG and TA-CABG. METHODS: We performed a retrospective observational study analyzing all consecutive adult patients aged >70 years undergoing first-time CABG over the 15-year period from 2004 to 2020 under a single surgeon. Primary outcomes of interest were in-hospital mortality, long-term mortality, and re-intervention rate. Secondary outcomes of interest included operative durations and the incidence of peri-operative complications. RESULTS: There were 46 patients (age 76 ± 3 SD) in the TA-CABG group and 145 patients (age 76 ± 4 SD) in the CO-CABG group. Cardio-pulmonary bypass and cross-clamp durations were comparable between groups (p = .11 and p = .23, respectively). Stroke occurred in 1.0% undergoing CO-CABG compared to 0% in the TA-CABG group (p = .42). Hospital mortality was 3.0% with CO-CABG (EuroSCORE; mean [SD] 6.81 (5.81)) and 2.0% with TA-CABG (EuroSCORE; mean [SD] 6.38 (6.57)) (p = .93). On long-term follow-up, myocardial infarction occurred in 10.0% of CO-CABG patients compared to 4.0% of TA-CABG patients (p = .25). Re-intervention rates were 7% following CO-CABG, and 2% after TA-CABG (p = .23). There was no significant difference in long-term mortality between patients undergoing CO-CABG and TA-CABG (47% vs. 57%, p = .27). Long-term survival was comparable between grafting techniques (p = .27). CONCLUSIONS: There were no significant differences in major adverse cardiac and cerebrovascular events, re-intervention rate, hospital or long-term mortality between CO-CABG and TA-CABG. TA-CABG represents a safe and feasible alternative to CO-CABG in elderly patients offering good long-term outcomes.

The impact of the quantitative assessment procedure for coronary artery bypass graft evaluations using high-resolution near-infrared fluorescence angiography.

PURPOSE: Near-infrared angiography (NIR) is used for on-site graft assessment during coronary artery bypass grafting. This study evaluated the results of a quantitative NIR assessment using a new high-resolution NIR device (h-NIR) for graft assessment. METHODS: Forty-three patients were enrolled in our study. Internal thoracic artery (ITA) grafts anastomosed to the left anterior descending artery and examined intraoperatively using h-NIR were included. The ITA grafts were divided into 2 groups for a comparative analysis: patent grafts (P group; n = 37) and failed grafts (F group; n = 6). The graft flow was evaluated by a "quantitative NIR assessment", and the fluorescence luminance intensity (FLI) was measured. Direct observation of the graft and anastomosis with h-NIR was also performed. RESULTS: The FLI was higher in the P group than in the F group. The receiver operating characteristic analysis revealed the following cut-off values for FLIs depending on imaging duration: 21.1% at 1 s, 35.5% at 2 s, 58.4% at 3 s, and 83.3% at 4 s. The sensitivity and specificity for detecting graft failure were 83.3% and 69.8-80.6%, respectively. Furthermore, h-NIR was also able to visualize arterial dissection in ITA grafts. CONCLUSIONS: A quantitative NIR assessment with an h-NIR device can improve the detectability of anastomotic stenosis, and h-NIR successfully detected arterial dissection of grafts.

Investigation of the effects of diabetes mellitus on left internal thoracic artery flow patterns in patients scheduled to undergo coronary bypass graft surgery.

PURPOSE: Diabetes mellitus (DM) plays a key role in the formation and prognosis of cardiovascular diseases. In this study, we aimed to investigate the effects of DM and glycemic control on left internal thoracic artery (LITA) Doppler flow in patients scheduled to undergo coronary artery bypass graft (CABG) surgery. METHODS: Patients who were hospitalized with a planned isolated CABG operation to our clinic between October 1, 2019 and March 1, 2020 were consecutively included in this prospective study. The patients were divided into three groups as those without DM (Group 1), those with DM and HbA1c values of below 7.5 (Group 2), and those with DM and HbA1c values of 7.5 and above (Group 3). The differences between the LITA Doppler flow patterns of the patients were analyzed. RESULTS: The mean ages of Group 1 (n = 103), Group 2 (n = 42), and Group 3 (n = 47) were 59.8 ± 9.6 years, 60.5 ± 9.3 years, and 61.9 ± 8.1 years, respectively. The groups differed in terms of diameter, volume, Vmax, pulsality index (PI), and resistive index (RI) values, both when the groups were compared among themselves (P < .001, for all), and when they were compared between those with (Groups 2 and 3) and without DM (Group 1) (P < .001, for all). Volume (R = -0.627, P < .001) and Vmax (R = -.450, P < .001) were moderately negatively correlated, while PI (R = .523, P < .001) and RI (R = 0.598, P < 0.001) were moderately positively correlated with HbA1c levels. CONCLUSION: In this study, we showed that increased HbA1c levels may be associated with significant functional and structural changes of LITA.

Successful endovascular repair with coil embolization of ruptured right internal thoracic artery aneurysm.

Internal thoracic artery aneurysms (ITAAs) are rare with wide variation in clinical presentation and a high risk of rupture. Endovascular techniques are increasingly being used for treatment of such aneurysms over surgical repair in recent times. A 34-year-old male presented with progressive swelling of the right anterior chest wall for 2 weeks and was diagnosed with right internal thoracic artery aneurysm with contained rupture. He underwent successful endovascular repair with coil embolization of ruptured right ITAA. Post intervention computed tomography (CT) angiography confirmed sealing of the ruptured aneurysm with no residual filling of the sac. At six months follow-up he is doing well with complete resolution of hematoma. This case demonstrates that an endovascular approach with coil embolization is a feasible and safe option for treating the rare ruptured ITAAs.

Os aneurismas da artéria torácica interna (ITAAs) são raros, com ampla variação na apresentação clínica e alto risco de ruptura. As técnicas endovasculares têm sido cada vez mais utilizadas para o tratamento desses aneurismas em relação ao reparo cirúrgico. Um homem de 34 anos de idade apresentou edema progressivo da parede torácica anterior direita por 2 semanas e foi diagnosticado com aneurisma da artéria mamária interna direita com ruptura contida. Ele foi submetido a reparo endovascular bem-sucedido, com embolização de ITAA direito roto. A angiotomografia computadorizada (angioTC) pós-intervenção confirmou o selamento do aneurisma rompido, sem enchimento residual do saco. No seguimento de 6 meses, ele estava bem, com resolução completa do hematoma. Este caso demonstra que a abordagem endovascular com embolização com molas é uma opção viável e segura no tratamento dos raros ITAAs rotos.

Life-threatening hemoptysis accompanied by internal thoracic artery aneurysms in a 28-year-old perinatal woman: a case report.

BACKGROUND: Life-threatening hemoptysis presents an immediate diagnostic and therapeutic challenge, especially during the perinatal period. CASE PRESENTATION: A 28-year-old perinatal woman with no significant past medical or surgical history presented with repeating hemoptysis and respiratory failure. Computed tomography revealed a 2.1 × 3.2  cm2 inhomogeneous tumorous lesion in the right superior mediastinum and a right main bronchus obstruction along with atelectasis of the right lung. Bronchoscopy showed a tumorous protrusion blocking the right main bronchus with active hemorrhage, and malignancy was suspected. Bronchial artery embolization (BAE) was performed to control the bleeding. The arteriogram revealed tortuosity, dilation and hypertrophy of the right bronchial arteries and aneurysms of the internal thoracic artery (ITA). The bleeding completely stopped after BAE. Bronchoscopy was performed again to remove residual blood clots. The patient recovered soon after the procedure and was discharged. CONCLUSIONS: Life-threatening hemoptysis concomitant with ITA aneurysms, which may have a misleading clinical diagnosis and treatment options, has not been reported previously in perinatal women. BAE could be used as a first-line treatment irrespective of the underlying causes.

Feasibility of bilateral internal thoracic artery harvesting using the da Vinci SP system.

PURPOSE: We conducted this study to investigate the feasibility of mobilizing the bilateral internal thoracic arteries (ITAs) using the da Vinci SP through a single intercostal incision and to compare the amount of rib spreading with that required for mini-thoracotomy procedures. We also evaluated the construction of an intrathoracic T-graft anastomosis using existing instrumentation of the SP system. METHODS: We harvested bilateral ITAs from two male cadavers via a single incision made in the fifth intercostal space using the da Vinci SP. A T-graft end-to-side anastomosis was created in one cadaver. RESULTS: The bilateral ITAs were harvested in less than 60 min and a T-graft was completed. No additional rib spreading was required. Intraoperative adjustments of the da Vinci SP were necessary to maintain alignment with the surgical targets. CONCLUSIONS: Bilateral ITA harvest using the da Vinci SP through a single intercostal incision was feasible, with less rib spreading than in mini-thoracotomy procedures. Thus, creating an intrathoracic T-graft with the existing da Vinci SP instruments is possible.

[Comparative study of vasa vasorum and neointima in conduits for coronary artery bypass grafting]. / Sravnitel'noe izuchenie vasa vasorum i neointimy v konduitakh dlia koronarnogo shuntirovaniia.

AIM: This study was undertaken to investigate the preoperative incidence and severity of intimal hypertrophy, as well as the level of blood supply of arterial and venous conduits for coronary artery bypass grafting. MATERIAL AND METHODS: Segments of the internal thoracic artery and great saphenous vein (n=13) were harvested pairwise during coronary artery bypass grafting and were then visualized by scanning electron microscopy in back-scattered electrons. The analysis of the incidence and thickness of intimal hypertrophy, as well as the calculation of the number and the area of the vasa vasorum were performed using the programme ImageJ. RESULTS: Intimal hypertrophy was more characteristic for the great saphenous vein as compared with the internal thoracic artery (9/13 (69.2%) and 7/13 (55.8%), respectively), although this difference did not reach statistical significance. The maximal-to-minimal neointimal thickness ratio correlated with the percentage of stenosis (r=0.875, p<0.0001), the area (r=0.45, p=0.023) and the number (r=0.47, p=0.015) of the vasa vasorum in the conduits, thus confirming the hypothesis on possible participation of these vessels in the development of intimal hypertrophy, with the area of the vasa vasorum being greater in the vessels with >10% stenosis (p=0.051). The number of the vasa vasorum in the great saphenous vein exceeded that in the internal thoracic artery (p=0.0005), with this difference remaining significant after adjustment for the area of the adventitia (p=0.027). The number of the vasa vasorum per the percentage of stenosis in the great saphenous vein also exceeded that in the internal thoracic artery (p=0.039) and more strongly correlated with intimal hypertrophy in the great saphenous vein as compared with that in the internal thoracic artery (r=0.53 and r=0.27, respectively). CONCLUSION: Intimal hypertrophy correlates with the area and number of the vasa vasorum in conduits. The great saphenous vein is characterised by a larger number and higher density of the vasa vasorum as compared with the internal thoracic artery. The number of the vasa vasorum is correlated with stenosis of the great saphenous vein more closely than with stenosis of the internal thoracic artery. This may be suggestive of significant predisposition of the great saphenous vein to the onset of adventitial inflammation followed by the development of intimal hypertrophy.