Coronary Artery Bypass Graft Patency Research Articles

Quantitative flow ratio to predict long-term coronary artery bypass graft patency in patients with left main coronary artery disease

PurposeFractional flow reserve (FFR) has been demonstrated in some studies to predict long-term coronary artery bypass graft (CABG) patency. Quantitative flow ratio (QFR) is an emerging technology which may predict FFR. In this study, we hypothesised that QFR would predict long-term CABG patency and that QFR would offer superior diagnostic performance to quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS).MethodsA prospective study was performed on patients with left main coronary artery disease who were undergoing CABG. QFR, QCA and IVUS assessment was performed. Follow-up computed tomography coronary angiography and invasive coronary angiography was undertaken to assess graft patency.ResultsA total of 22 patients, comprising of 65 vessels were included in the analysis. At a median follow-up of 3.6 years post CABG (interquartile range, 2.3 to 4.8 years), 12 grafts (18.4%) were occluded. QFR was not statistically significantly higher in occluded grafts (0.81 ± 0.19 vs. 0.69 ± 0.21; P = 0.08). QFR demonstrated a discriminatory power to predict graft occlusion (area under the receiver operating characteristic curve, 0.70; 95% confidence interval [CI], 0.52 to 0.88; P = 0.03). At long-term follow-up, the risk of graft occlusion was higher in vessels with a QFR > 0.80 (58.6% vs. 17.0%; hazard ratio, 3.89; 95% CI, 1.05 to 14.42; P = 0.03 by log-rank test). QCA (minimum lumen diameter, lesion length, diameter stenosis) and IVUS (minimum lumen area, minimum lumen diameter, diameter stenosis) parameters were not predictive of long-term graft patency.ConclusionsQFR may predict long-term graft patency in patients undergoing CABG.

Appropriateness criteria for the use of cardiac computed tomography, SIC-SIRM part 2: acute chest pain evaluation; stent and coronary artery bypass graft patency evaluation; planning of coronary revascularization and transcatheter valve procedures; cardiomyopathies, electrophysiological applications, cardiac masses, cardio-oncology and pericardial diseases evaluation.

In the past 20 years, cardiac computed tomography (CCT) has become a pivotal technique for the noninvasive diagnostic workup of coronary and cardiac diseases. Continuous technical and methodological improvements, combined with fast growing scientific evidence, have progressively expanded the clinical role of CCT. Randomized clinical trials documented the value of CCT in increasing the cost-effectiveness of the management of patients with acute chest pain presenting in the emergency department, also during the pandemic. Beyond the evaluation of stents and surgical graft patency, the anatomical and functional coronary imaging have the potential to guide treatment decision-making and planning for complex left main and three-vessel coronary disease. Furthermore, there has been an increasing demand to use CCT for preinterventional planning in minimally invasive procedures, such as transcatheter valve implantation and mitral valve repair. Yet, the use of CCT as a roadmap for tailored electrophysiological procedures has gained increasing importance to assure maximum success. In the meantime, innovations and advanced postprocessing tools have generated new potential applications of CCT from the simple coronary anatomy to the complete assessment of structural, functional and pathophysiological biomarkers of cardiac disease. In this complex and revolutionary scenario, it is urgently needed to provide an updated guide for the appropriate use of CCT in different clinical settings. This manuscript, endorsed by the Italian Society of Cardiology (SIC) and the Italian Society of Medical and Interventional Radiology (SIRM), represents the second of two consensus documents collecting the expert opinion of cardiologists and radiologists about current appropriate use of CCT.

Influence of HbA1c Levels on Long-Term Coronary Artery Bypass Graft Patency

Influence of HbA1c Levels on Long-Term Coronary Artery Bypass Graft Patency

Stress testing-guided assessment of coronary artery bypass grafts patency, at 6 months of follow up. A prospective study

Purpose: To assess the coronary bypass grafts patency and the repeat revascularization rate, six months after coronary artery bypass grafting (CABG). Methods: We prospectively enrolled 145 consecutive patients undergoing isolated CABG between June 2014 and June 2016. We performed at 6 months of follow up a coronary computed tomography angiography (CTA) in patients whose stress tests were negative and an invasive coronary angiography (ICA) in the opposite case. Results: A total of 134 CTA and 11 ICA were performed, allowing the analysis of 321 grafts, including 143 left internal thoracic arteries (LITA), 89 right internal thoracic arteries (RITA) and 89 saphenous veins grafts (SVG). The average graft patency was 95.1% for LITA, 84.3% for RITA and 64% for SVG. The best patencies were obtained when these grafts were anastomosed to the left anterior descending artery (LAD): 96.3% for LITA, and 87.5% for RITA. SVG patency was homogeneous whether between the main right coronary artery and its branches (63.4% versus 65% respectively. p = 1), or between circumflex and RCA (72.7% versus. 63.9% respectively. p=0.6). On the right and circumflex coronary arteries, the patency of the SVG was significantly lower than that of RITA (66.26% versus 83.95% respectively, p = 0.011). At 6 months of follow up, the repeat revascularization rate was 2.07% (n=3/145). Conclusions: 6 months after CABG, RITA and LITA had good patencies especially on LAD, while SVG was occluded in almost a third of cases. On the circumflex and right coronary arteries, SVG patency was significantly lower than that of RITA. Keywords: Coronary Artery Bypass; Exercise Testing; Coronary Angiography; Computed Tomography Angiograph

Graft Patency Rate and Risk Factors for Graft Failure among Symptomatic Post Coronary Artery Bypass Graft Surgery Patients

BACKGROUND Malaysia, a multiracial country, has been burdened by ischemic heart disease, the leading cause of death for the past 10 years. The success of coronary artery bypass grafting surgery (CABG) particularly depends on the continued patency of aortocoronary grafts. The study aims to identify the graft patency rate and risk factors of graft failure among symptomatic post CABG patients. METHODS Data were collected from 80 patients with a history of CABG, who underwent conventional coronary angiography for refractory angina in Hospital Sultanah Aminah Johor, Malaysia from January 2014 till December 2018. The graft patency was evaluated with conventional coronary angiography. Graft patency was assessed with the Kaplan-Meier method. Differences between graft patency were tested with log-rank test at a 5% significance level and result with p-value <0.05 was considered statistically significant. RESULTS Among the 80 post CABG patients with cardiac symptoms, there were 2 patients with acute myocardial infarction (2.5%) and 24 patients with NSTEMI (30%). 22 patients (27.5%) were found to have all grafts patent despite being persistently symptomatic. Left internal mammary arterial (LIMA) graft remained as the best conduit with a significantly better short, medium, and long term patency (up to 20 years) compared to SVG graft (Log-rank test, p-value < 0.05). Indian race and age less than 70 years had higher risk of SVG graft stenosis. CONCLUSION Type of conduits remains the most important factor in determining the coronary artery bypass graft patency, with LIMA produces the best patency rate in both short and long term.

Less Invasive Reoperative Ventricular Assist Device Insertion for Patients With Patent Bypass Grafts

We report our technique for left ventricular assist device insertion that is useful in patients with patent coronary artery bypass grafts or mediastinal adhesions from other previous surgeries. An inverted-T upper hemisternotomy is made at the level of the second or third intercostal space, and with the left sternal section retracted, dissection is carried along the chest wall into the left pleural space. The device is implanted in the left ventricular apex via a left thoracotomy in the fifth or sixth intercostal space. The outflow graft is routed through the left pleural space and anastomosed to the ascending aorta.

Coronary Artery Bypass Graft Patency and Survival in Patients on Dialysis

BackgroundLittle is known about graft patency after coronary artery bypass grafting (CABG) performed in patients on dialysis. Our aim was to assess patency of internal thoracic artery (ITA) grafts and saphenous vein grafts (SVGs) in these patients. MethodsFrom 1/1997 to 1/2018, 500 patients on dialysis underwent primary CABG with or without concomitant procedures at Cleveland Clinic, 40 of whom had 48 postoperative angiograms for recurrent ischemic symptoms. Complete follow-up was obtained on all but 1 patient lost to follow-up 1 y after CABG. Thirty-six ITA grafts and 65 SVGs were evaluable for stenosis and occlusion. ResultsTwo of 40 patients (5%) had emergency CABG; 3 (7.5%) with calcified aortas had a change in operative strategy to avoid ascending aortic manipulation, 2 (5%) had poor conduit quality, and 12 (30%) had severe diffuse atherosclerotic disease with calcification of the coronary targets causing technical difficulties. Thirty-three patients (82%) were bypassed with an in situ ITA and 3 (7.5%) had a free ITA graft. Three of 36 ITA grafts were occluded at 0.78, 1.8, and 9.4 y (too few to model). SVG patency was 52% and 37% at 1 and 2 y, respectively. ConclusionsAmong patients on dialysis who underwent CABG, coronary angiography for ischemic symptoms in a select subset revealed that SVG patency was lower than expected from published reports in the general CABG population and may contribute to the poor prognosis of this cohort. Further work is needed to guide graft selection and improve graft patency in dialysis patients.

The state of the art for arterial coronary artery bypass grafting

The selection of conduit has always been one of the most perennially debated topic in the field of coronary artery bypass grafting (CABG) . Arterial grafts have demonstrated excellent biological characteristics and long-term patency in CABG. Clinical observations and randomized clinical trials over the past two decades have shown that the internal thoracic artery is the gold standard graft. Multi-arterial and total-arterial CABG significantly improves patients' long-term survival, but there are technical challenges and concerns of sternal complication. Currently multi-arterial and total-arterial CABG are strongly advocated and increasingly applied worldwide. Several guidelines have been published and updated, as well as Chinese expert consensus. Coronary surgery in China is paving anupper stage of quality improvement. Arterial coronary artery bypass grafting should be carried out more broadly in China as evidence accumulation and excellent long-term clinical results.

COVID-19 - Endothelial Axis and Coronary Artery Bypass Graft Patency: a Target for Therapeutic Intervention?

It has been reported that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection induces endothelial inflammation, therefore facilitating the progression of endothelial and vascular dysfunction in coronavirus disease 2019 (COVID-19) patients. Coronary artery bypass grafting (CABG) involves mainly the use of the saphenous vein (SV) and internal mammary artery as graft material in the stenosed coronary arteries. Unfortunately, graft patency of the SV is low due to endothelial dysfunction and inflammation. We propose that SARS-CoV-2 might cause vascular inflammation, endothelial dysfunction, and thrombosis in coronary artery bypass graft vessels by binding angiotensin-converting enzyme 2 receptor. Therefore, in this Special Article, we consider the potential influence of COVID-19 on the patency rates of coronary artery bypass graft vessels, mainly with reference to the SV. Moreover, we discuss the technique of SV graft harvesting and the therapeutic potential of focusing on endothelial dysfunction, vascular inflammation, and thrombosis for protecting coronary artery bypass grafts in COVID-19 infected CABG patients.

Imaging characteristics of acute type A aortic dissection and candidacy for repair with ascending aortic endografts

BackgroundAcute type A aortic dissection (ATAD) remains associated with substantial short-term mortality, and despite increasing rates of surgical repair, as many as 10% to 20% of patients do not undergo surgery because of comorbidities and dissection-related complications. For patients unable to undergo open repair, previous attempts at endovascular treatment of ATAD used devices originally designed for deployment in the descending thoracic aorta. Industry has begun to support early investigational devices meant specifically for placement within the ascending aorta. We evaluated relevant aortic parameters to examine which patients may be candidates for repair with an ascending aortic endograft. MethodsWe reviewed 100 consecutive patients in our institutional ATAD database with contrast-enhanced computed tomography imaging on an Aquarius iNtuition workstation (TeraRecon, San Mateo, Calif), using curved planar reformatting (vessel tracking) and orthogonal views for measurements. We compared relevant aortic measurements against proposed criteria for future ascending endografts, including various landing zone diameters and intimal tear distances from the distal coronary ostium. ResultsOf the 100 patients examined, 39% had proximal intimal tears located outside the tubular ascending aorta. In all, 30% were excluded on the basis of either the presence of a prosthetic aortic valve or significant aortic insufficiency, and 6% were excluded on the basis of the presence of patent coronary artery bypass grafts from the ascending aorta. Many patients had multiple exclusion criteria, and based on various proposed criteria, overall candidacy ranged from 2% to 23%. If a maximum landing zone diameter of 42 mm and intimal tears as little as 20 mm distal to the distalmost coronary were considered treatable, only 8% of patients would have been candidates compared with 20% candidacy if aortic diameters up to 46 mm and intimal tears as little as 10 mm distal to the distalmost coronary were considered treatable. The most frequent single cause for exclusion was inadequacy of the proximal landing zone. Iliofemoral vascular access was also assessed and deemed adequate in >90% of cases. ConclusionsA minority of patients suffering ATAD would currently qualify for ascending aortic endografting on the basis of anatomic criteria alone. Future device designs should take into account these common anatomic exclusion criteria so that more versatile devices may be developed and commercially available to treat a larger number of patients.

RF95 VENOUS VS ARTERIAL COMPOSITE Y-GRAFT IN CABG: A COMPUTATIONAL FLUID-STRUCTURE STUDY

Background and Aim: Arterial or venous conduits used for Y-graft have different outcomes in terms of risk of restenosis and subsequent graft failure in coronary artery bypass grafting (CABG). The aim of the study was to investigate how the choice of the graft conduit predicts the risk of graft failure. Methods: We performed a computational fluid dynamics numerical simulation (FSI) analysis to describe the blood flow in the coronary arteries and grafts. Different Y-grafts with radial artery (RA) or saphenous vein (SV) were investigated by changing their mechanical properties (Young's modulus) and geometric characteristics. Coronary artery stenosis degree was also virtually varied, to assess the fluid behaviour in relation to the severity of the stenosis. Relative Residence Time (RRT) and Von Mises (VM) stresses were used as indicators of disturbed fluid-dynamic and for the analysis of the wall mechanics, respectively. Results: A more disturbed fluid-dynamic was observed for lower stenosis degree. Retrograde flow was present in the RA graft for the 50% and 70% stenosis degree. RRT values were higher in lower stenosis degree and both grafts. RRT and VM stresses were higher for the SV graft. Conclusions: Venous Y-graft is characterized by a more disturbed flow at the anastomosis site with a higher vessel's wall shear stress compared to the arterial one. Because of the potentially negative effects of competitive flow in low-grade native coronary artery stenosis, we confirm the better long-term patency in arterial CABG for critical coronary stenosis.

TCT-207 Intraoperative optical coherence tomography as a new modality to determine coronary artery bypass graft patency. Our first experience

Since 2009 intraoperative coronary bypass angiography (ICAB) included in to CABG protocol and performed routinely as an end point surgical myocardial revascularization at A.N. Bakulev National Medical Research Center of Cardiovascular Surgery. Even though ICAB, in most of the cases, allows to

ASSESSMENT OF THE ROLE OF 128 ROW MULTI DETECTOR COMPUTED TOMOGRAPHY IN THE EVALUATION OF CORONARY ARTERY BYPASS GRAFTS PATENCY

Background: The recently developed 128 row multidetector CT had made a revolution in coronary artery bypass grafts(CABG) patency evaluation due to high temporal and spatial resolution beside it is being non invasive.Subjects and Methods: 50 patients were enrolled for ECG gated CT of coronary arteries bypass grafts between January 2015and May 2017.Patients underwent conventional coronary angiography within 2 weeks of MDCT exam. Administration of beta blocker andnitroglycerin was done prior to CT exam. Breath hold training was mandatory.Results: 46 grafts were arterial and 74 were venous. 36 of the arterial grafts (78.2 %) were patent, 6 (13 %) were significantlynarrowed and 4 (8.8 %) were completely occluded. Regarding venous grafts, 52 (70.2 %) of them were patent, 14 (19 %) weresignificantly narrowed and 8 (10.8 %) were completely occluded. CT angiography compared to the conventional angiographyas a gold standard technique gave us a sensitivity of 100%, a specificity of about 98% and an accuracy of about 93.6% in theassessment of any type of coronary artery grafts.Conclusion: MDCT is considered the imaging modality of choice at the current days to evaluate the patency and stenosis ofcoronary artery bypass grafts than the conventional coronary angiography due to its multiple drawbacks.

Predictive Value of Mean Platelet Volume in Saphenous Vein Graft Disease.

ObjectiveTo determine whether mean platelet volume (MPV), platelet distribution width (PDW), and platelet count could be used as determinants of mortality following coronary artery bypass graft (CABG) surgery and patency of saphenous vein grafts (SVG).MethodsThe records of 128 patients who underwent emergency or elective coronary angiography after CABG surgery, and who died at an early stage were retrospectively reviewed. Patients were divided into three groups as early death, no SVG disease (SVGD), and SVGD group. MPV, PDW, and platelet count were evaluated at different times.ResultsMPV was significantly higher in the stenotic group than in the nonstenotic group (9.7±1.8 fl and 8.2±0.9 fl, P<0.05). The postoperative MPV ratio was found to be higher in the stenotic group when compared to the preoperative period (9.6±1.8 fl and 7.8±0.9 fl, P<0.05). MPV values were also found to be higher in patients who died during the early stage than in surviving patients (9.4±1.9 fl and 8.0±1.0 fl, P<0.05). There was no statistically significant difference regarding platelet count and PDW ratios between the early deaths group and surviving patients. An MPV value higher than 10.6 predicted SVGD with 85% sensitivity and 45% specificity; and an MPV higher than 7.9 predicted early death with 80% sensitivity and 68% specificity were observed.ConclusionMPV may be a useful indicator for the prediction of SVGD and mortality following CABG surgery.

Predictive value of circulating microvesicles in coronary artery bypass graft patency

Predictive value of circulating microvesicles in coronary artery bypass graft patency

Influence of Diabetes on Long-Term Coronary Artery Bypass Graft Patency

BackgroundNearly 50% of patients undergoing coronary artery bypass grafting have diabetes. However, little is known about the influence of diabetes on long-term patency of bypass grafts. Because patients with diabetes have more severe coronary artery stenosis, we hypothesized that graft patency is worse in patients with than without diabetes. ObjectivesThis study sought to examine the influence of diabetes on long-term patency of bypass grafts. MethodsFrom 1972 to 2011, 57,961 patients underwent primary isolated coronary artery bypass grafting. Of these, 1,372 pharmacologically treated patients with diabetes and 10,147 patients without diabetes had 15,887 postoperative angiograms; stenosis was quantified for 7,903 internal thoracic artery (ITA) grafts and 20,066 saphenous vein grafts. Status of graft patency across time was analyzed by longitudinal nonlinear mixed-effects modeling. ResultsITA graft patency was stable over time and similar in patients with and without diabetes: at 1, 5, 10, and 20 years, 97%, 97%, 96%, and 96% in patients with diabetes, and 96%, 96%, 95%, and 93% in patients without diabetes, respectively (early p = 0.20; late p = 0.30). In contrast, saphenous vein graft patency declined over time and similarly in patients with and without diabetes: at 1, 5, 10, and 20 years, 78%, 70%, 57%, and 42% in patients with diabetes, and 82%, 72%, 58%, and 41% in patients without diabetes, respectively (early p < 0.002; late p = 0.60). After adjusting for patient characteristics, diabetes was associated with higher early patency of ITA grafts (odds ratio: 0.63; 95% confidence limits: 0.43 to 0.91; p = 0.013), but late patency of ITA grafts was similar in patients with and without diabetes (p = 0.80). Early and late patency of saphenous vein grafts were similar in patients with and without diabetes (early p = 0.90; late p = 0.80). ConclusionsContrary to our hypothesis, diabetes did not influence long-term patency of bypass grafts. Use of ITA grafts should be maximized in patients undergoing coronary artery bypass grafting because they have excellent patency in patients with and without diabetes even after 20 years.

Predictive value of circulating microparticles signature in coronary artery bypass graft patency

Predictive value of circulating microparticles signature in coronary artery bypass graft patency

Impact of functional focal versus diffuse coronary artery disease on bypass graft patency

BackgroundPressure guidewire pullback recording can differentiate between functional focal and diffuse disease types in coronary artery disease. The aim of this study was to compare the outcome of coronary artery bypass graft (CABG) patency between patients with functional focal versus diffuse disease types in recipient coronary arteries. Methods and resultsWe investigated 89 patients who underwent pressure guidewire pullback in the left anterior descending (LAD) artery before CABG using internal mammary artery (IMA). Based on the pressure guidewire pullback data, the LAD lesions were classified into functional focal disease (abrupt pressure step-up; n=58) or functional diffuse disease (gradual pressure increase; n=31). Follow-up computed tomography (CT) angiography was conducted within 1year after CABG to assess the bypass graft patency. Pre CABG, LAD angiographic percent diameter stenosis (57±10% vs. 54±12%, p=0.228) and fractional flow reserve (FFR) (0.68±0.07 vs. 0.69±0.07, p=0.244) were not different between the functional focal and diffuse disease groups. The CABG procedure characteristics were similarly comparable between the two groups. In the follow-up CT angiography after CABG, occlusion or string sign of the IMA graft to LAD was more frequently observed in the functional diffuse disease group than in the functional focal disease group (26% vs. 7%, p=0.021). ConclusionIn CABG, functional diffuse disease in the recipient coronary artery was associated with an increased risk of the graft failure in comparison with functional focal disease.

Diagnostic accuracy and effective radiation dose of high pitch dual source multidetector computed tomography in evaluation of coronary artery bypass graft patency

The aim of the study was to evaluate the diagnostic accuracy and effective radiation dose (ERD) of high pitch dual source multidetector computed tomography (MDCT) for coronary artery bypass graft (CABG) patency. Fourty-five patients who underwent 128× 2‑slice MDCT angiography with aprospective electrocardiogram-triggering, low-dose, high pitch, dual source, flash spiral acquisition mode after CABG surgery were included in the study. The interobserver agreement of the image quality was evaluated with Cohen κvalue. The image quality was compared to the heart rates (HRs) using Mann-WhitneyU test and to the graft segments using χ(2) test. The findings for the CABG patency on MDCT were compared to those determined on catheter coronary angiography. Dose-length product (DLP) and ERD were compared to the gender, HRs, and body mass index (BMI) of the patients using Kruskall Wallis and Mann-WhitneyU tests. Atotal of 110 grafts and 330 vessel segments were evaluated with agood interobserver agreement (κ= 0.80). The image quality was better in proximal and middle graft segments (p< 0.05), as well as in the patients with low HRs (p< 0.05). High pitch MDCT had the following sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for evaluation of graft patency: 92.8, 99.3, 92.8, 99.3 and 98.8 %, respectively. ERD was correlated to the HRs and BMI. High pitch 128× 2‑slice dual source CT angiography is anoninvasive imaging modality, and it can be safely and effectively used in evaluation of CABG patency with lower radiation dose.

Revascularization for stable ischemic heart disease: are there new parallels between percutaneous coronary intervention and coronary artery bypass grafting?

In patients with stable ischemic heart disease, revascularization is undertaken when optimal medical therapy fails, using percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) as appropriate and determined by the local Heart Team. For years, both revascularization strategies have been based on angiographically assessed anatomy alone. Now, using anatomy and physiology to guide intervention has been definitively shown to be superior to an anatomy-only approach in multicenter trials in PCI, documenting the importance of the regional myocardial perfusion status on outcomes. Since cath-lab physiologic evaluation is a pre-intervention assessment that impacts PCI outcomes, is regional myocardial perfusion important to CABG outcomes as well? Novel intraoperative imaging data are presented to document that in stable ischemic heart disease, competitive flow, graft patency and late mortality in CABG are influenced by the regional myocardial perfusion status of the grafted vessels. This n...