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Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Background and Aim: The biological behaviour of coronary graft conduits over time may be considered by serial angiography., Methods: A single institution retrospective cohort received mostly clinically indicated angiography between 1997 and 2020, following coronary bypass surgery. Only perfectly patent grafts (absence of any lumen irregularity) for each conduit type at the first postoperative angiogram were selected for a later comparison. The latest angiograms were at least 5 years postoperatively, and at least 1 year after first postoperative angiogram. Analysis was done according to each graft (anastomosis). Comparisons used generalised estimating equations, adjusted for binary logistic regression., Results: Of 143 patients, there were 410 of 468 (87.6%) perfectly patent grafts at the first angiogram, analysed at 6.8±4.0 years postoperative, of which 157 were internal mammary arteries, 228 were radial arteries, and 25 were saphenous veins. At the latest angiogram (12.2±3.8 years postoperative), comparison with the first angiogram for each individual graft found preserved perfect patency for internal mammary arteries, 156 of 157 (99.4%), and for radial arteries, 227 of 228 (99.6%) but saphenous veins deteriorated considerably, 13 of 25 (52.0%). The two arterial grafts (internal mammary and radial) were superior to vein grafts (odds ratio 163; 95% confidence interval [CI] 22-1,211; p<0.001), but not different from each other (odds ratio 0.95; 95% CI 0.78-1.16; p=0.584)., Conclusions: From a position of known angiographic perfect patency post-CABG, internal mammary artery and radial artery grafts retained their perfect patency in the longer term, but saphenous vein grafts did not., Competing Interests: Conflicts of Interest None declared., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Although coronary artery bypass graft (CABG) surgery is a well-established intervention, graft failure can occur, and the underlying mechanisms remain incompletely understood. The purpose of this prospective study is to utilize computational fluid dynamics (CFD) to investigate how graft hemodynamics one month post surgery may vary among graft types, which have different long-term patency rates. Twenty-four grafts from 10 participants (64.6 ± 8.5 years, 9 men) were scanned with coronary CT angiography and 4D flow MRI one month after CABG surgery. Grafts included 10 left internal mammary arteries (LIMA), 3 radial arteries (RA), and 11 saphenous vein grafts (SVG). Image-guided CFD was used to quantify blood flow rate and wall area exposed to abnormal wall shear stress (WSS). Arterial grafts had a lower abnormal WSS area than venous grafts (17.9% vs. 70.1%; p = 0.001), and a similar trend was observed for LIMA vs. SVG (13.8% vs. 70.1%; p = 0.001). Abnormal WSS area correlated positively to lumen diameter (p < 0.001) and negatively to flow rate (p = 0.001). This CFD study is the first of its kind to prospectively reveal differences in abnormal WSS area 1 month post surgery among CABG types, suggesting that WSS may influence the differential long-term graft failure rates observed among these groups., (© 2022. The Author(s) under exclusive licence to Biomedical Engineering Society.)

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., (© 2021. Springer Nature Singapore Pte Ltd.)

Background: The use of the left internal thoracic artery (LITA) is the gold standard in coronary artery bypass graft surgery (CABG). Multiarterial grafting for CABG is being increasingly emphasized. This study aimed to resolve the utility of the right internal thoracic artery (RITA) for multiple CABG as "free" RITA and described new evidence., Methods: One hundred sixty-three patients received solo CABG with bilateral internal thoracic arteries between 2005 and 2018. The RITA was used as in situ RITA, group A (n = 62), and the composite graft created with saphenous vein graft (SVG), group B (n = 101). The patency rate and graft size of the composite free RITA and SVG were examined by coronary computed tomography angiography., Results: The average number of distal anastomoses per patient was 3.4 ± 1.0 in group A, and 4.2 ± 1.1 in group B (P < .001). The sequential grafting with free RITA was in 86 patients. The patency rate of both LITA and RITA was similar in both groups. In group B, 40 patients received late computed tomography angiography at a mean of 46 months (range, 17 to 175). The late patency rate was 95.1% in LITA and 96.9% in free RITA. The diameter of free RITA increased from 2.06 ± 0.34 mm to 2.37 ± 0.23 mm (P = .036); that of in situ LITA increased from 2.08 ± 0.51 mm to 2.44 ± 0.49 mm (P = .047); and that of composite SVG decreased from 4.1 ± 0.9 mm to 2.6 ± 0.7 mm (P < .001)., Conclusions: Multiple bypass grafting can be sufficiently achieved with LITA and free RITA. The growth potential of free RITA and in situ LITA might play the important role of expected long-term patency., (Copyright © 2021 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Although minimally invasive direct coronary artery bypass (MIDCAB) is a less invasive procedure, internal thoracic artery (ITA) harvesting is difficult. A 65-year-old woman was advised to undergo MIDCAB for recurrent in-stent restenosis. We harvested the ITA using three-dimensional endoscopy without robotics and determined the scope position using enhanced computed tomography. We changed the camera installation between the wound and the camera port, according to the harvesting site with a harmonic scalpel using the skeletonized technique. We harvested the ITA from the subclavian vein level superiorly to the xyphoid process level inferiorly.

Objective: Multivessel minimally invasive coronary artery bypass grafting, performed chiefly with left internal thoracic artery and saphenous vein grafts through a left anterolateral thoracotomy, has recently emerged as an alternative to conventional coronary artery bypass grafting. The present study involves our initial experience with respect to early postoperative and angiographic outcomes after total arterial multivessel off-pump minimally invasive coronary artery bypass grafting with bilateral internal thoracic arteries., Methods: A total of 88 consecutive patients undergoing total arterial off-pump minimally invasive coronary artery bypass grafting with bilateral internal thoracic arteries without ascending aortic manipulation were included in this study. Bilateral internal thoracic arteries were harvested under direct vision through a left anterolateral thoracotomy and used as Y or in situ grafts. Multivessel grafting was performed off pump. Postoperative graft assessment was performed in 51 patients., Results: The mean age of patients was 67.1 ± 7.2 years, and 79 patients (89.8%) were male. The mean body mass index and ejection fraction were 26.7 ± 2.7 kg/m 2 and 57.6% ± 6.6%, respectively, and 40 patients (45.5%) had left main disease. No intraoperative conversions to cardiopulmonary bypass or sternotomy occurred. A total of 209 distal anastomoses (mean 2.4 ± 0.5) were performed, with 57 patients undergoing double, 29 patients undergoing triple, and 2 patients undergoing quadruple coronary artery bypass grafting. There was no in-hospital mortality, and 5 patients underwent reexploration for bleeding. No patient had stroke or chest wound infections. Predischarge coronary angiography revealed an overall graft patency rate of 96.8%., Conclusions: Off-pump minimally invasive coronary artery bypass grafting using total arterial revascularization with bilateral internal thoracic arteries is a feasible and safe operation that is associated with excellent short-term outcomes and early graft patency. Future studies should focus on improving the generalizability and reproducibility of this technique., (Copyright © 2020 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Quantitative myocardial perfusion mapping using cardiovascular magnetic resonance (CMR) is validated for myocardial blood flow (MBF) estimation in native vessel coronary artery disease (CAD). Following coronary artery bypass graft (CABG) surgery, perfusion defects are often detected in territories supplied by the left internal mammary artery (LIMA) graft, but their interpretation and subsequent clinical management is variable., Methods: We assessed myocardial perfusion using quantitative CMR perfusion mapping in 38 patients with prior CABG surgery, all with angiographically-proven patent LIMA grafts to the left anterior descending coronary artery (LAD) and no prior infarction in the LAD territory. Factors potentially determining MBF in the LIMA-LAD myocardial territory, including the impact of delayed contrast arrival through the LIMA graft were evaluated., Results: Perfusion defects were reported on blinded visual analysis in the LIMA-LAD territory in 27 (71%) cases, despite LIMA graft patency and no LAD infarction. Native LAD chronic total occlusion (CTO) was a strong independent predictor of stress MBF (B = - 0.41, p = 0.014) and myocardial perfusion reserve (MPR) (B = - 0.56, p = 0.005), and was associated with reduced stress MBF in the basal (1.47 vs 2.07 ml/g/min; p = 0.002) but not the apical myocardial segments (1.52 vs 1.87 ml/g/min; p = 0.057). Extending the maximum arterial time delay incorporated in the quantitative perfusion algorithm, resulted only in a small increase (3.4%) of estimated stress MBF., Conclusions: Perfusion defects are frequently detected in LIMA-LAD subtended territories post CABG despite LIMA patency. Although delayed contrast arrival through LIMA grafts causes a small underestimation of MBF, perfusion defects are likely to reflect true reductions in myocardial blood flow, largely due to proximal native LAD disease.

Background: The clinical use of the radial artery (RA) in coronary artery bypass grafting (CABG) is still limited worldwide, although it has been recommended by several guidelines. Multidetector computed tomography (MDCT) is widely used to evaluate graft patency, as invasive coronary angiography could cause potentially serious risks including bleeding, dissection and stroke. This study aims to report the short-term results of the RA in CABG with MDCT., Methods: The study population consists of 41 consecutive patients undergoing elective CABG with the RA graft between 2017 to 2018, with MDCT performed to evaluate graft patency during follow-up, and target vessels for the RA were non-left anterior descending coronary arteries with > 70% stenosis., Results: A total of 150 grafts were assessed by MDCT during follow-up (mean, 8.9 ± 5.1 months). MDCT could clearly show the structure and patency of grafts, even for complex coronary artery revascularization. Graft patency of the left internal mammary artery was 92.9% (39/42), with the RA patency of 84.4% (38/45) and the patency of the saphenous vein graft of 81.1% (30/37). And the RA anastomosed to the left coronary artery system might have better patency than the RA anastomosed to the right coronary artery system (25/29, 86.2% vs 13/16, 81.3%, p = 0.686)., Conclusions: The short-term patency rate of RA grafts is good, and the RA might be associated with better patency when anastomosed to the left but not the right coronary artery. MDCT could provide excellent visualization of grafts in CABG.

Purpose: The left internal mammary artery (LIMA) is the preferred graft for coronary artery bypass grafting, but the reasoning for LIMA occlusion is unclear. We sought to examine whether the wall shear stress (WSS) values of LIMA grafts during the perioperative period reflected the 1-year patency by using combining computational fluid dynamics (CFD) and coronary computed tomography angiography (CCTA) images., Methods: CCTA was performed in 233 patients with LIMA graft perioperatively and 1 year later from October 2014 to May 2017. LIMA occlusion was detected in six patients at the 1-year follow-up CCTA. Two patients were excluded due to poor imaging quality. The remaining four patients were enrolled as occlusive (OCC) group, and eight patients with patent LIMA were recruited as patent (PAT) group. The WSS values of LIMA during perioperative period were calculated. LIMA graft was artificially divided into three even segments, proximal (pLIMA), middle (mLIMA) and distal (dLIMA) segments. The independent samples t -test and the Student-Newman-Keuls test were used., Results: The WSS values of dLIMA were significantly higher in the PAT group than in the OCC group (4.43 vs. 2.56, p  < 0.05). The WSS values of dLIMA in the PAT group were significantly higher than pLIMA, which was absent in the OCC group., Conclusions: A higher WSS value of the distal segment of LIMA and a higher WSS value of the distal segment compared with the proximal segment of LIMA in the PAT were observed; this tendency might be helpful in predicting the 1-year patency of LIMA., Competing Interests: None declared., (Thieme. All rights reserved.)

Background: The method of coronary-coronary bypass grafting was described in 1987 but has not been widely used, and there are only a few studies that report good short-term and mid-term results as well as some individual cases of long-term follow-up. In our medical institution, we carried out an analysis of the long-term results of coronary-coronary bypass grafting, which are presented in this study., Methods: This was a retrospective single-center study on 95 patients who underwent coronary-coronary bypass grafting as a supplement to the standard coronary bypass grafting procedure. All patients underwent angiographic assessment of the coronary bypass grafts during the long-term follow-up period. The observation period was up to 123 months. Angiographic assessment of 109 coronary-coronary grafts was carried out., Results: Twelve (7.6%) arterial and 11 (19.3%) venous conduits were found to be occluded, and 8 (10.3%) arterial and 10 (31.3%) venous coronary-coronary grafts were occluded during the observation period., Conclusion: Arterial coronary-coronary artery bypass grafting represents an alternative technique that allows complete myocardial revascularization.

The surgical treatment of anomalous origin of the coronary artery remains controversial. We present 3 cases of young adults who underwent free right internal thoracic artery to right coronary artery bypass for the treatment of symptomatic anomalous origin of the right coronary artery., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Where each patient has all three conduits of internal mammary artery (IMA), saphenous vein graft (SVG) and radial artery (RA), most confounders affecting comparison between conduits can be mitigated. Additionally, since SVG progressively fails over time, restricting patient angiography to the late period only can mitigate against early SVG patency that may have occluded in the late period., Methods: Research protocol driven conventional angiography was performed for patients with at least one of each conduit of IMA, RA and SVG and a minimum of 7 years postoperative. The primary analysis was perfect patency and secondary analysis was overall patency including angiographic evidence of conduit lumen irregularity from conduit atheroma. Multivariable generalized linear mixed model (GLMM) was used. Patency excluded occluded or "string sign" conduits. Perfect patency was present in patent grafts if there was no lumen irregularity., Results: Fifty patients underwent coronary angiography at overall duration postoperative 13.1 ± 2.9, and age 74.3 ± 7.0 years. Of 196 anastomoses, IMA 62, RA 77 and SVG 57. Most IMA were to the left anterior descending territory and most RA and SVG were to the circumflex and right coronary territories. Perfect patency RA 92.2% was not different to IMA 96.8%, P = 0.309; and both were significantly better than SVG 17.5%, P < 0.001. Patency RA 93.5% was also not different to IMA 96.8%, P = 0.169, and both arterial conduits were significantly higher than SVG 82.5%, P = 0.029. Grafting according to coronary territory was not significant for perfect patency, P = 0.997 and patency P = 0.289. Coronary stenosis predicted perfect patency for RA only, P = 0.030 and for patency, RA, P = 0.007, and SVG, P = 0.032. When both arterial conduits were combined, perfect patency, P < 0.001, and patency, P = 0.017, were superior to SVG., Conclusions: All but one patent internal mammary artery or radial artery grafts had perfect patency and had superior perfect patency and overall patency compared to saphenous vein grafts.

Coronary artery bypass grafting (CABG) plays an important role in the treatment of symptomatic coronary artery disease. During the fifty years since the first operation, a great amount of clinical observations confirm that the internal mammary artery (IMA) can be used for the bypass grafting by the most favorable outcome. IMA's histological structure and physiological properties make it resistant to atherosclerosis. In our article, we remember the first CABG operation in Hungary using IMA graft and we also confirm the favorable properties of IMA by the results of the 35-year follow-up, with the longest reported coronary angiography in the literature after IMA grafting. On the basis of this case, we can speculate that the prostacyclin secretion of the mammary graft can prevent the run-off tract of the left anterior descending (LAD) artery from the atherosclerotic progression. Large-scale study is warranted to compare the long-term prognosis of the run-off tract after grafting versus stenting of the LAD. Orv Hetil. 2020; 161(9): 354-358.

Background: The importance of a coronary artery, based on the myocardial mass it perfuses, is well documented, but little is known about the importance of a vessel that has been bypassed and its effect on survival in the context of bilateral internal thoracic artery (BITA) grafting., Objectives: This study determined the effect of a dominant left anterior descending (LAD) artery and important non-LAD targets on outcomes after BITA grafting., Methods: From January 1972 to January 2011, of 6,127 patients who underwent BITA grafting, 2,551 received 1 ITA grafted to the LAD and had an evaluable coronary angiogram. A dominant LAD was defined as one that was wrapped around the left ventricular apex. Non-LAD targets were graded based on their terminal reach toward the apex: important: >75% (n = 1,698); and less important: ≤75% (n = 853). Mean follow-up was 14 ± 8.7 years. Multivariable analysis was performed to identify risk factors for time-related mortality., Results: A dominant LAD was present more frequently in patients with less important additional targets (51% vs. 35%; p < 0.0001). A total of 179 patients (7.0%) received a second ITA to multiple targets, 77 (43%) of which were to multiple important target vessels. Unadjusted late survival was similar regardless of degree of importance of the second ITA target-77% at 15 years (p = 0.70) for the important and less important targets, respectively. In the multivariable model, grafting the second ITA to multiple important targets was associated with better long-term survival (p = 0.005). In patients with a nondominant LAD, a second ITA grafted to a less important artery was associated with higher risk of operative mortality (2.4% vs. 0.51%; p = 0.007). A saphenous vein graft to an important or less important target did not influence long-term survival., Conclusions: In BITA grafting, bypassing multiple important targets to maximize myocardium supplied by ITAs improved long-term survival. In patients with a nondominant LAD, selecting an important target for the second ITA lowered operative mortality., (Copyright © 2020 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Purpose of Review: To summarize the available evidence on the use of the right internal thoracic artery (RITA) and the radial artery as the second arterial graft in coronary artery bypass surgery., Recent Findings: The current data support the equipoise of the two conduits in terms of clinical and angiographic outcomes. Both RITA and radial artery have better patency than saphenous vein grafts. The use of the RITA carries an increased risk of deep sternal wound infection (DSWI) if the artery is harvested as pedicle. Bilateral internal thoracic artery grafting is more technically demanding than radial artery use and there is a volume-outcome relationship in terms of mortality and incidence of DSWI. The radial artery is preferable over RITA in right-sided or distal circumflex artery targets with high-degree stenosis and in patients at higher risk for DSWI, whereas it is not recommended to graft vessels with moderate stenosis and in cases of insufficient collateralization from the ulnar artery or previous transradial procedures., Summary: The patency rate and clinical outcomes of radial artery and RITA are similar. The use of one or the other should be based on a careful evaluation of the patient's coronary anatomy and comorbidities, the conduit availability and the surgeon's and center's experience.

Coronary artery anomalies (CAA) are anatomical aberrations in the origin, structure, and course of the epicardial arteries. Literature has detailed common anomalies or fistulas formed because of coronary artery bypass grafting (CABG) manipulation of intrathoracic vessels. Despite the commonality of the CABG procedure, there are a few CAA and fistula findings which remain extremely rare. We present a case of left internal mammary artery to pulmonary artery fistula causing coronary steal syndrome that presented symptomatically as a malignant arrhythmia. Following a literature review of therapy, intervention, and management we recommend a team based approach when faced with this extremely rare case presentation. The goal of management should to reduce symptoms, and ischemia, by reducing or stopping flow through the fistula and out of the coronary blood supply., (© 2019 Wiley Periodicals, Inc.)

A best evidence topic was constructed according to a structured protocol. The question addressed was whether the configuration of bilateral internal thoracic arteries (BITAs) influences survival, patency or repeat revascularization in patients undergoing coronary artery bypass grafting. Five hundred and seventy-one papers were found using the reported searches, of which 8 represented the best evidence to answer the clinical question. One systematic review, 4 randomized trials and 3 observational studies were selected. The authors, date, journal, study type, population, main outcome measures and results are tabulated. All 4 prospective randomized trials found no significant difference in graft patency or mortality when comparing Y-graft and in situ configurations. Three of the 4 randomized trials found no difference in major adverse cardiovascular and cerebrovascular events or repeat revascularization at follow-up. An exception was Glineur et al. (Bilateral internal thoracic artery configuration for coronary artery bypass surgery: a prospective randomized trial. Circ Cardiovasc Interv 2016;9:7), who found that the Y-configuration resulted in lower rates of major adverse cardiovascular and cerebrovascular events. All 3 observational studies reviewed found no alteration in survival, cardiac events or repeat revascularization between in situ and Y-graft BITA configurations. One systematic review found similar outcomes with respect to mortality, cardiac events and repeat revascularization with in situ and composite BITA. In summary, existing literature demonstrates no difference in clinical outcomes between composite and in situ graft configurations. Furthermore, the configuration of BITA does not affect mortality, graft patency or repeat revascularization.

Background Perivascular adipose tissue ( PVAT ) is causally associated with vascular function and the pathogenesis of vascular disease in association with metabolically driven chronic inflammation called metaflammation. However, the difference in PVAT surrounding the coronary artery ( CA - PVAT ) and that surrounding the internal thoracic artery (ITA-PVAT), a vessel resistant to atherosclerosis, remains unclear. Herein, we investigated whether CA - PVAT , ITA - PVAT , and subcutaneous adipose tissue ( SCAT ) have distinct phenotypes. Methods and Results Fat pads were sampled from 44 patients (men/women, 36:8; age, 67±13 years) with CA disease who underwent elective CA bypass grafting. Adipocyte size in ITA - PVAT and that in CA - PVAT were significantly smaller than that in SCAT . A greater extent of fibrosis and increased gene expression levels of fibrosis-related molecules were observed in CA - PVAT than those in SCAT and those in ITA - PVAT . CA - PVAT exhibited more pronounced metaflammation, as indicated by a significantly larger extent of CD 68-positive and CD 11c-positive M1 macrophages, a lower ratio of CD 206-positive M2 to CD 11c-positive M1 macrophages, a lower gene expression level of adiponectin, and higher gene expression levels of inflammatory cytokines and inflammasome- and endoplasmic reticulum stress-related molecules, than did ITA - PVAT and SCAT . Expression patterns of adipocyte developmental and pattern-forming genes were totally different among SCAT , ITA - PVAT, and CA - PVAT . Conclusions The phenotype of ITA - PVAT is closer to that of SCAT than that of CA - PVAT , which may result from inherent differences in adipocytes. ITA - PVAT appears to be protected from metaflammation and consecutive adipose tissue remodeling, which may contribute to the decreased atherosclerotic plaque burden in the ITA.

Objective: Over the past 10 years, the rate of patients who have undergone coronary artery bypass graft (CABG) surgery has increased twofold in cases of coronary angiography. Today, transradial access is the first choice for coronary angiography. We aimed to compare the efficacy and reliability of radial versus femoral access for coronary angiography in post-CABG surgery in this study., Methods: Data from 442 patients who underwent post-CABG surgery between 2012-2017 were retrospectively compared. The right radial route was used in 120 cases, the left radial route in 148, and femoral route in 174. These three pathways were compared in terms of procedure time and fluoroscopy time, efficacy, and complication development. Comparisons among the three groups were performed with Bonferroni test for continuous variables and chi-square or Fisher's exact test for nominal variables as a binary., Results: Comparison results indicate that femoral access was better than left radial access and the left radial access was better than right radial access in terms of fluoroscopy time (10.71±1.65, 10.94±1.25, 16.12±5.28 min, P<0.001) and total procedure time (17.28±1.68, 17.68±2.34, 23.04±5.84 min, P<0.001). The left radial pathway was the most effective way of viewing left internal mammary artery (LIMA). No statistically significant differences were found among the three groups in other graft visualizations, all minor complications, total procedure and fluoroscopy time "Except LIMA imaging". Mortality due to processing was not observed in all three groups., Conclusion: The left radial route is preferred over right radial access for post-CABG angiography because the left radial pathway is close to the LIMA and is similar to the femoral pathway. In LIMA graft imaging, right radial access is a reliable route, even though it is not as effective as other pathways. We hope that the right radial pathway will improve with physician experience and innovations.

Objective: The aim of the present study was to identify morphological and pathophysiological factors associated with long-term patency of grafts used in coronary artery bypass grafting (CABG)., Methods: A total of 127 patients who underwent CABG between 2000 and 2006 and presented for computed tomography evaluation of graft patency at 139.78±36.64 months post-CABG were analyzed. Patients received 340 grafts (2.68 grafts/patient), 399 distal anastomoses (3.14 anastomoses/ patient), 220 (55.14%) performed using arterial grafts, and 179 (44.86%) using saphenous vein grafts (SVGs)., Results: Graft patency varied according to vessel type and coronary territory. Overall graft patency was 90.16% for the left internal thoracic artery (LITA), 75.55% for the right internal thoracic artery (RITA), 79.25% for the radial artery (RA), and 74.3% for the SVG. The maximum patency rate was obtained with the RA (80.65%) for the right coronary territory, RITA (92.86%) for the anterolateral territory, and SVG (82.54%) for the circumflex territory. The LITA-left anterior descending artery graft occluded in 13 (7.93%) cases, 7 due to competitive flow. The influence of graft length on patency rates after indexing to height was not significant. The target vessel degree of stenosis influenced arterial graft patency rates with an occlusion odds ratio (OR) of 3.02 when anastomosed to target vessels with <90% stenosis. Target vessel caliber also influenced patency rates with occlusion ORs of 2.63 for SVGs and 2.31 for arterial grafts when anastomosed to ≤1.5 mm target vessels., Conclusion: Morphological parameters, such as graft type, target territory, target vessel caliber, and degree of stenosis, are important factors conditioning long-term graft patency.

Background: The left internal thoracic artery (LITA) is the most commonly used arterial bypass conduit in coronary artery bypass graft (CABG) patients and inadequate LITA flow can result in an increase in morbidity and mortality. In this study, we evaluated the effect of excision of the distal spasmodic segment of the LITA on the free flow in CABG patients., Methods: This study consisted of 47 patients who underwent elective CABG performed with or without other cardiac surgery, between July 2015 and December 2015. Excised LITA length was shorter than 15mm in group 1, between 15mm and 30mm in group 2 and longer than 30mm in group 3. Left ITA free flow was measured for 60seconds into a container before and after the distal LITA excision. The inter-measurement differences were calculated for the three groups. Thereafter, the comparison was performed in terms of free flow difference amongst the three groups., Results: The mean difference of LITA free flow was 27.6±22.7ml/minute in group 1, 35.4±26.7ml/minute in group 2, and 52.6±26.1ml/minute in group 3. There were significant differences in terms of free flow difference between the groups (p=0.008). Also, differences were statistically significant in group 1 versus group 3 (p=0.003) and group 2 versus group 3 (p=0.038) in the intergroup comparisons., Conclusions: The distal part of the LITA has more spasmodic potential than other segments. This spasm may result in low flow of LITA grafts. Therefore, an as long as possible excision of the distal LITA segment may be required to avoid the spasmodic effect., (Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

The "Achilles heel" of coronary artery bypass graft (CABG) surgery is graft patency. While long-term patency is determined by the type of conduit and the progression of graft and native vessel disease, short-term patency is affected by intra-operative technical issues. Transit-time flow measurements and epicardial ultrasound have been shown to accurately assess intra-operative graft patency. This review will examine the evidence to support the premise that intra-operative graft assessment is essential in determining graft patency and should be the standard of care when performing CABG surgery., (© 2018 Wiley Periodicals, Inc.)

Background: The long-term benefits of a third arterial conduit to the right circulation in triple-vessel disease remain debatable. This retrospective, single-center, propensity-matched study investigates the impact of a third arterial conduit to the right circulation on early and intermediate survival after coronary artery bypass grafting., Methods: Data were retrospectively collected from 2004 to 2014 for all surgical revascularizations for triple-vessel disease with at least 2 arterial conduits to the left circulation and a third arterial or venous conduit to the right circulation. A total of 167 pairs were propensity matched to arterial versus venous third conduit to right circulation. Hazard functions were obtained with Cox multivariate regression and Kaplan-Meier survival curves were compared between the matched cohorts., Results: Extracardiac arteriopathy, logistic euroSCORE, and left main stem disease were significant predictors of adverse survival. A third arterial conduit to the right circulation was not a significant predictor of improved survival in multivariate analysis (HR, 0.72; 95% CI, 0.34-1.55; P = .411). 30-day mortality was 0.6% in both groups. There was no significant difference in early or intermediate survival in the propensity-matched groups (venous vs arterial, 99.2% vs 99.2%; P = 1.000 at 1 year; 85.2% vs 88.8%; P = .248 at 5 years and 69.2% vs 88.8%; P = .297 at 7 years) CONCLUSIONS: The use of a third arterial versus a venous conduit to the right circulation does not improve early or intermediate survival up to 7 years in triple-vessel coronary artery disease in this study. Longer follow-up and larger cohorts may be needed for differences to emerge., (Copyright © 2017 The American Association for Thoracic Surgery. All rights reserved.)

A 79-year-old woman had an atretic LIMA to LAD but without significant LAD stenosis, patent SVG to OM1, patent SVG to RCA, and severe tandem lesions in a very tortuous LCX for which she underwent PCI. Placement of a BMW coronary guidewire into the LCX resulted in the straightening of the vessel.

This study aimed to evaluate the feasibility and the mid-term efficacy of an in situ skeletonized right internal mammary artery (IMA) bypass grafting to a left anterior descending artery (LAD), and to determine risk factors for IMA graft failure in a single-center study.From January 2012 to December 2015, 189 patients (173 males, 50.6 ± 6.0 years old) undergoing first isolated coronary artery bypass grafting surgery with the in situ skeletonized right IMA grafting to the LAD were included in this study. Baseline characteristics, peroperative data, and follow-up outcomes were investigated and analyzed.The length of the in situ skeletonized right IMA grafts was 18.6 ± 1.2 cm (17.0-22.0 cm). Intraoperative graft flow of the in situ skeletonized right IMA grafting to LAD was 42 ± 9 mL/minute (18-72 mL/minute) associated with measured pulsatility index of 0.8-4.3. In-hospital mortality was 0.5%. Postoperative morbidity included acute myocardial infarction (0.5%), stroke (0.5%), and deep sternal wound infections (1.1%). The mid-term survival was 97.2% and the incidence of repeat revascularization was 0.6%. The patency rate of the in situ skeletonized right IMA grafting to the LAD was 97.1% by computed tomography angiography examination during the follow-up period of 23.2 ± 9.7 months. Additionally, logistic regression analysis showed that intraoperative graft flow had an independent influence on the risk of the mid-term right IMA graft failure.The strategy of the in situ skeletonized right IMA grafting to the LAD is feasible and effective. Intraoperative graft flow was an independent risk factor for the mid-term right IMA graft failure.

Objective: Totally endoscopic coronary artery bypass grafting was shown to be feasible and safe, with excellent clinical and angiographic mid-term results. Data on long-term outcome are lacking. Therefore, we aimed to investigate the long-term rate of major adverse cardiac and cerebrovascular events and left internal mammary artery patency rate in patients undergoing arrested heart totally endoscopic coronary artery bypass grafting., Methods: From 2001 to 2012, a total of 208 arrested heart-totally endoscopic coronary artery bypass grafting patients were prospectively included. Mean ± SD age was 58.8 ± 9.4 years, and mean ± SD Society of Thoracic Surgeons score was 0.5 ± 0.5%. Major adverse cardiac and cerebrovascular events were defined as a composite of death, myocardial infarction, stroke, re-percutaneous coronary intervention, re-coronary artery bypass graft, and target vessel revascularization. Left internal mammary artery patency was assessed using cardiac computed tomography and depicted according to the established Fitzgibbon classification. Mean ± SD follow-up was 6.9 ± 2.3 years., Results: At 1, 5, and 10 years, survival rate was 100%, 98.3%, and 95.8%, respectively. The freedom from clinical events at 1, 5, and 10 years were major adverse cardiac and cerebrovascular events (93.5%, 85.9%, and 83.0%), myocardial infarction (99.0%, 97.4%, and 95.9%), target vessel revascularization (96.0%, 94.3%, and 91.7%), re-percutaneous coronary intervention (94.5%, 91.6%, and 84.2%), and re-coronary artery bypass graft (100%, 99.5%, and 99.5%), respectively. Left internal mammary artery patency rate at 1, 5, and 10 years was 100%, 94.9%, and 88.1%, respectively., Conclusions: Arrested heart-totally endoscopic coronary artery bypass grafting shows excellent clinical long-term results with a left internal mammary artery patency rate comparable with conventional coronary artery bypass graft at 10 years after surgery.

Transit-time flow measurement (TTFM) is a reliable method to check the graft function intraoperatively in coronary surgery. The given parameters are: Mean Graft Flow (MGF); Pulsatility Index (PI) and Insufficiency Ratio (%BF). Some cutoffs of these parameters have been identified as predictors for unfair 1-y clinical outcome: mean graft flow (MGF) less than 20 ml/min and high pulsatility index greater than 5. Other cutoffs have been found as related to postoperative angiography: MGF 15 ml/min or less and pulsatility index at least 3 (sensitivity 94%; specificity 61%); MGF less than 15 ml/min and pulsatility index greater than 3 for left coronary artery or pulsatility index greater than 5 for right coronary artery (sensitivity 96%; specificity 77%); MGF 15 ml/min or less and pulsatility index at least 5.1 left coronary artery (sensitivity 98%; specificity 26%). Hence, with the need to improve the diagnostic accuracy of TTFM, high-resolution epicardic coronary ultrasound module has been added to graft flow evaluation providing 2D ultrasound imaging (either in short-axis or long-axis) and color-flow mapping, allowing an accurate morphological evaluation of body graft and anastomosis. An intraoperative method aimed to verify coronary grafts should be easy to handle, not time consuming, minimally invasive, easily meaningful and relatively cheap; in addition, it should offer objective parameters more than qualitative criteria. We herein report the results of our experience with intraoperative graft verification with TTFM and high-resolution imaging along with a systematic review of the literature in this field with the aim to provide a road map to be followed.

Purpose: The HyperEye Medical System (HEMS) uses indocyanine green (ICG) to visualize blood vessels in coronary artery bypass grafting (CABG). We performed quantitative HEMS assessment to detect grafts at risk of occlusion., Methods: We assessed the HEMS angiograms of 177 grafts from 69 patients who underwent CABG and compared the results with those of fluoroscopic coronary angiography, by measuring the increasing rate of ICG intensity, average acceleration value, and time to peak luminance intensity., Results: Grafts in the patent and failed groups showed significant differences in their increasing rate of intensity and average acceleration value. The average accelerations value of ICG intensity of internal thoracic artery (ITA) and saphenous vein (SV) grafts were 112.3 and 144.9 intensity/s 2 in the patent group, and 71.0 and 91.8 intensity/s 2 in the failed group. The time to peak luminance intensity was 1.7 and 1.4 s in the patent group and 2.3 and 1.9 s in the failed group; these values were not significantly different., Conclusion: Significant reductions in the ICG intensity rate and average acceleration value can occur in failed grafts. Therefore, quantifiable changes in ICG intensity may help detect minute changes in blood flow.

Transit time flow measurement (TTFM) is a quality control tool for intraoperative graft evaluation in coronary artery bypass graft (CABG) surgery. A critical review of the literature available using TTFM in CABG surgery is the focus of this article. The main objectives will be to detail precise parameters for flow evaluation, to show limitations of TTFM and to prove its predictive impact on postoperative graft failure rate. Publications listed in the PubMed database were reviewed, searching for intraoperative graft verification in coronary surgery by TTFM, with postoperative imaging follow-up (FU) modality and with a special focus on publications released after European guidelines from 2010. Nine included publications revealed an overall graft failure rate of ∼12%. Mean graft flow had a positive predictive value in the largest study, and cut-offs, of at least 20 ml/min for internal mammary artery (IMA) grafts, therein partially confirming guidelines, and 30-40 ml/min for saphenous venous grafts (SVGs) were proposed. An explicit correlation between graft flow, patency rate and severity of coronary stenosis, by indicating the fractional flow reserve, was found for IMA grafts. Increased pulsatility index and increased systolic reverse flow probably predict worse outcome and may help identifying competitive flow. Diastolic filling, rarely indicated, could not be confirmed as the predictive marker. No significant correlation of TTFM and graft failure rate for radial and other arterial grafts could be found, partially due to the small number of these types of grafts analysed. Larger target vessels and lower postoperative CK-MB levels may predict better graft patency rates. Low sensitivity for TTFM to reliably detect graft failure is certainly a major issue, as found in randomized analyses. However, methodical limitations and varying threshold values for TTFM render a general consensus difficult. Influence of quantity (vessel territory distribution) and quality (myocardial scar) of the graft perfusion area, on TTFM and FU outcome, was not included by anyone and should be part of future research. TTFM is probably not the tool of choice to detect progressive late graft failure of SVG. Peroperative TTFM values should be correlated with one type of conduit, differentiating between early and late graft failure (by applying a uniform, appropriated definition), to precise and confirm threshold values., (© The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Coronary artery bypass graft perforation during percutaneous coronary intervention is a rare complication. Perforation of a left internal mammary artery (LIMA) graft due to a guide catheter extension system has not been described. We report the successful deployment of a polytetrafluoroethylene (PTFE)-covered stent to seal the LIMA graft perforation due to the guide catheter extension system. Percutaneous coronary intervention was performed for a culprit lesion of the distal left circumflex via the LIMA graft. A balloon catheter failed to be delivered because the LIMA graft was very long and tortuous. The guide catheter extension system was introduced, and the balloon was delivered and inflated. However, the LIMA graft perforation with continuous extravasation was caused by the edge of deeper intubated guide extension catheter when a coronary stent was attempted to be delivered to the culprit lesion. A long balloon inflation was performed, but the perforation was not completely sealed. The PTFE-covered stent was successfully deployed and sealed the LIMA graft perforation. This case describes that the rapid deployment of PTFE-covered stent is effective to treat severe coronary artery bypass graft perforation due to the guide catheter extension system., (Copyright © 2016 Elsevier Inc. All rights reserved.)

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.

Background: Bilateral internal thoracic arteries (BITA) have demonstrated superior patency and improved survival in patients undergoing coronary artery bypass grafting. However, the optimal configuration for BITA utilization and its effect on long-term outcome remains uncertain., Methods and Results: We randomly assigned 304 patients undergoing coronary artery bypass grafting using BITA to either in situ or Y grafting configurations. The primary end point was 3-year angiographic patency. Secondary end points included major adverse cardiac and cerebrovascular events (ie, death from any cause, stroke, myocardial infarction, or repeat revascularization) at 7 years. More coronary targets were able to be revascularized using internal thoracic arteries in patients randomized to Y grafting versus in situ group (3.2±0.8 versus 2.4±0.5 arteries/patient; P<0.01). The primary end point did not show significant differences in graft patency between groups. Secondary end points occurred more frequently in the in situ group (P=0.03), with 7-year rates of 34±10% in the in situ and 25±12% in the Y grafting groups, driven largely by a higher incidence of repeat revascularization in the in situ group (14±4.5% versus 7.4±3.2% at 7 years; P=0.009). There were no significant differences in hospital mortality or morbidity or in late survival, myocardial infarction, or stroke between groups., Conclusions: Three-year systematic angiographic follow-up revealed no significant difference in graft patency between the 2 BITA configurations. However, compared with in situ configuration, the use of BITA in a Y grafting configuration results in lower rates of major adverse cardiovascular and cerebrovascular events at 7 years., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01666366., (© 2016 The Authors.)

There have been some recent reports on the surgical treatment of lung cancer in patients following previous coronary artery bypass graft surgery. Use of internal thoracic artery graft is a gold standard in cardiac surgery with superior long-term patency. Left internal thoracic artery graft is usually patent during left lung resection in patients who present to the surgeon with an operable lung cancer. We have presented our institutional experience with left-sided thoracic surgery in patients who have had previous coronary artery surgery with a patent internal thoracic artery graft., (Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.)

The radial artery is increasingly used as a second arterial conduit for myocardial revascularization. However, the radial artery is susceptible to vasospasm, which is thought to be the principal cause of graft failure. The radial artery is harvested as a skeletonized or a non-skeletonized graft, but the effect of different harvesting technique remains unknown. In this study, we compared the early- and mid-term angiographic findings to elucidate its influence on the graft luminal diameter. We harvested 39 radial arteries either as a skeletonized (n = 18) or a non-skeletonized graft (n = 21) using an ultrasonic scalpel. We constructed a composite straight graft by combining a right internal thoracic artery and a radial artery. All the radial artery grafts were sequentially anastomosed to coronary arteries. We measured the diameters of the radial arteries before the operation, within 1 month and 1 year after the operation. At early postoperative period, graft diameter was significantly larger in skeletonized grafts. Graft diameter at the point before the first and the second anastomosis was similar in skeletonized grafts, although that was significantly smaller before the second anastomosis in non-skeletonized grafts. However, 1 year after the operation, the graft diameter was comparable and equally reduced after the first anastomosis in both groups. Skeletonization with an ultrasonic scalpel increases the luminal diameter of the radial artery graft at early postoperative period, which, however, reduces possibly as adaptation to graft flow 1 year after the operation.

Background:  In conventional coronary artery bypass grafting (CABG), multiple anastomoses in the ascending aorta are needed for multiple coronary targeting. We have introduced a single-site proximal anastomosis technique for multiple coronary targeting. A single anastomosis between the ascending aorta and graft was performed using a side-to-side maneuver (Cabrol type). Additionally, the graft was connected to another graft by end-to-end anastomosis for the coronary artery on the opposite side. We evaluated the long-term clinical outcome and graft patency of this Cabrol-type aortocoronary anastomosis technique., Methods:  From 2002 to 2012, a total of 483 patients (mean age, 64.6 years) underwent CABG using our Cabrol-type aortocoronary anastomosis technique. The average number of target coronary arteries per person was 3.4 ± 0.6. The mean follow-up duration was 74.2 ± 31.3 months; 98.7% of hospital survivors completed the follow-up. Postoperative coronary computed tomography angiography was performed in 377 patients (81.8%)., Results:  Operative mortality was 4.6%. The actuarial overall survival rates at 1, 5, and 10 years were 97.8 ± 0.7%, 89.3 ± 1.5%, and 69.0 ± 3.9%, respectively. The actuarial major adverse cardiac and cerebrovascular event-free survival rates at 1, 5, and 10 years were 95.7 ± 0.9%, 80.1 ± 2.0%, and 60.8 ± 3.7%, respectively. One- and 5-year patency rates of the Cabrol-type aortocoronary graft were 81.1 ± 2.2% and 61.3 ± 3.6%, respectively., Conclusion:  Our Cabrol-type aortocoronary anastomosis technique did not have superior clinical outcomes and graft patency compared with conventional CABG. However, this technique might be an alternative option in select patients with atherosclerotic disease of the ascending aorta, or other embarrassing situations., (Georg Thieme Verlag KG Stuttgart · New York.)

Aneurysmal dilatation of aortocoronary saphenous vein grafts (SVG) is a rare but known complication after coronary artery bypass grafting (CABG). They are most commonly found incidentally, although some may present with unstable angina or myocardial infarction (MI). Rarely, these aneurysms can develop into fistulas to the neighboring cardiac chambers. We report the case of a 66-year old woman with a history of CABG in 1996 with a left internal mammary artery (LIMA) graft to the left anterior descending and a SVG to distal right coronary artery presenting with non-ST segment elevation myocardial infarction (NSTEMI) complicated with congestive heart failure. Selective Coronary and Graft angiography showed an aneurysm in the mid SVG with a fistula into the right atrium (RA) resulting in a significant left to right shunt. The significant left to right shunt diverted blood flow from right coronary artery territory resulting in recurrent ischemia and angina and introduced a significant volume overload on the right ventricle resulting in over heart failure. Secondary to the course of LIMA graft along the sternum, surgery was not an option. Secondary to continued symptoms percutaneous intervention was performed with placement of two 6.0 x 50 mm Viabahn self-expanding covered stent with aggressive post-dilation resulting in successful closure with no residual flow. Percutaneous intervention is shown to be an effective approach to manage both aortocoronary fistula and grafts ruptures and is associated with better outcomes than surgical and conservative options. To the best of our knowledge, this is the first reported case of a successful closure of fistulous communication of a SVG aneurysm to the RA utilizing multiple peripheral covered stents.

The left internal mammary artery (LIMA) is the preferred arterial graft to be used for the left anterior descending (LAD) artery for coronary artery bypass graft (CABG) due to high graft patency rate. LIMA dissection is a rare, but dreadful complication of graft angiography and may lead to serious complications including death, myocardial infarction (MI), and re-do CABG. Transcatheter management of LIMA dissection involves multiple stenting. However, this may leave a dissection flap at the ostium of the LIMA that may extend to the left subclavian artery jeopardizing flow to the left arm and vertebral artery. We present a case of LIMA dissection where a dual balloon angioplasty was used for the first time offering better "sealing" of the dissection flap at the level of the ostium of the LIMA graft/subclavian artery.

Coronary artery steal syndromes may occur following coronary artery bypass grafting as a result of the presence of large side-branches arising from the internal mammary artery (IMA). Coil embolization, Amplatzer Vascular Plug and graft stents are all used for the treatment of such syndromes. The literature contains limited data on the long-term success of these treatment methods. There is no large series regarding occluded IMA side branches causing coronary steal phenomena, and data on long-term follow-up of this treatment method is also very limited. This report presented two cases and their treatment, and reviewed the advantages and disadvantages of treatment methods and the factors that affect successful treatment.

The left internal thoracic artery (LITA) is considered the most reliable coronary artery bypass grafting conduit due to its high rate of long-term patency. LITA grafts are extremely durable and associated complications are infrequent. We present a case with spontaneous spiral dissection of a LITA graft to the left anterior descending artery, which was assessed by optical coherence tomography (OCT) and intravascular ultrasound (IVUS). OCT was superior in visualizing the disrupted flap, false lumen, and intramural hematoma, but it did not visualize the full extent of the vessel wall. In contrast, IVUS allowed more complete and deeper vessel visualization, and thus better appreciation of the extent of intramural hematoma. Combined use of these two modalities provides complementary details on imaging of a LITA dissection.