No-Touch Saphenous Vein Harvesting May Improve Further the Patency of Saphenous Vein Composite Grafts: Early Outcomes and 1-Year Angiographic Results

Morphologic changes of the no-touch saphenous vein as Y-composite versus aortocoronary grafts (CONFIG Trial)

OBJECTIVE

This randomized controlled trial was aimed to compare 1-year morphologic changes of the no-touch saphenous vein graft as Y-composite (Composite group) versus aortocoronary (Aorta group) configurations in coronary artery bypass grafting.

METHODS

The primary endpoint was intima-media thickness of the saphenous vein graft as measured by intravascular ultrasound (IVUS) at the 1-year angiographic evaluation. Recruitment of 25 patients in each group was necessary based on a superiority design. Among the 50 patients, IVUS data were obtained in 22 and 24 patients from the Composite and Aorta groups, respectively.

RESULTS

Mean age was 64.8 ± 9.2 years, and the proportion of females was 20.0%. The numbers of distal anastomoses per saphenous vein graft were 2.7 ± 1.1 and 2.6 ± 0.8 in the Composite and Aorta groups, respectively. The intima-media thickness of the saphenous vein graft 1 year after surgery were 0.25 ± 0.04 mm and 0.24 ± 0.06 mm in the Composite and Aorta groups, respectively (P for superiority = .99). Other IVUS parameters of saphenous vein grafts, including vessel diameter, luminal diameter, and the ratio of intima-media thickness to vessel diameter, also demonstrated no differences between the groups. No neointimal hyperplasia or plaque formation was detected using IVUS. All study patients underwent 1-year angiographic evaluation, and the patency rates were 94.7%(89 out of 94 anastomoses) and 100.0%(90 out of 90 anastomoses) in the Composite and Aorta groups, respectively.

CONCLUSIONS

The intima-media thickness of the saphenous vein graft 1 year after surgery demonstrated no significant difference between the Y-composite and aortocoronary configurations (NCT04782492). Trial Registration: ClinicalTrials.gov NCT04782492.

Improved Technique Reduce Lower Limb Complications After the Traditional No-Touch Technique for Vein Graft Harvesting: A Single-Center Retrospective Historical Controlled Study

Objective

The employment of the no-touch technique in harvesting the great saphenous vein (GSV) for coronary artery bypass grafting has been associated with a significant improvement in clinical patency rates. Despite these advantages, such grafts may predispose patients to complications in the lower limbs. This study endeavors to evaluate the incidence of complications in the lower extremities by deploying an enhanced protocol for the no-touch harvesting technique.

Methods

The historical control group in this study included patients who underwent coronary artery bypass grafting (CABG) with the no-touch technique for GSV harvesting at our institution from August 2018 to April 2020, in compliance with ethical standards. The intervention group consisted of patients who received CABG and were subjected to an optimized no-touch technique for GSV harvesting from May 2020 to June 2022. Technical modifications were applied to reduce lower limb complications, including limited use of electrocautery, minimization of extravascular tissue preservation, relaxation of postoperative elastic compression bandages, and elevation of the lower extremities. These measures aimed to decrease the incidence of postoperative lower limb complications, such as pain, numbness, edema, exudation, and delayed healing. The occurrences of postoperative complications were meticulously documented, compared, and analyzed between the two groups.

Results

The adoption of the optimized no-touch technique resulted in a significant decrease in the incidence of postoperative lower extremity incisional complications among patients subjected to off-pump CABG (p < 0.05).

Conclusion

The results of this study substantiate that the application of an optimized no-touch technique to harvest the GSV significantly diminishes the incidence of postoperative lower limb complications in patients receiving CABG. These results highlight the importance of adopting and integrating this optimized technique into clinical protocols, emphasizing its critical role in advancing patient care outcomes.

Prediction of functional coronary stenosis by computed tomography-derived fractional flow reserve in surgical revascularization

Objectives

The aims of this study were (1) to compare computed tomography-derived fractional flow reserve (CT-FFR) values with graft patency and (2) to establish the cut-off value of CT-FFR for predicting competitive graft flow after coronary artery bypass grafting (CABG).

Methods

Of the 77 patients who underwent isolated CABG with an in situ internal thoracic artery (ITA)-based composite graft and who were also evaluated by preoperative cardiac CT, CT-FFR values were obtained in 74 patients. Early postoperative angiograms were performed in all 74 patients. Angiograms were performed to evaluate the grafts as well as the native coronary arteries to find any competitive flow present. Postoperative angiographic findings of graft flow were categorized as perfectly patent, bidirectionally competitive, unidirectionally competitive, and occluded. Receiver operating characteristic curve analysis of preoperative CT-FFR values for predicting postoperative angiographic competition was performed, and cutoff values of CT-FFR and area under the curve were identified.

Results

In total, 234 anastomoses were performed in 74 patients (median 3 [interquartile range, 2, 4] anastomoses per patient). Postoperative (median 1 [interquartile range, 1, 2] day) angiograms showed that 196 (83.8%) anastomoses were perfectly patent, 25 (10.7%) anastomoses were bidirectionally competitive, 12 (5.1%) anastomoses were unidirectionally competitive, and 1 (0.4%) anastomosis was occluded. Median CT-FFR values of the coronary arteries with perfectly patent, bidirectionally competitive, and unidirectionally competitive grafts were 0.658 (interquartile range, 0.500, 0.725), 0.809 (interquartile range, 0.789, 0.855), and 0.849 (interquartile range, 0.833, 0.865), respectively. The cutoff value of CT-FFR predicting competitive graft flow was 0.774 (sensitivity, 97.4%; specificity, 98.5% [area under the curve 0.977; P < .001]).

Conclusions

The diagnostic accuracy of CT-FFR for predicting competitive graft flow after CABG was high, and CT-FFR could be used as a guide for predicting functional coronary artery stenosis in surgical revascularization.

No-touch saphenous vein: current understanding of the conduit 'less handled'

PURPOSE OF REVIEW

The no-touch technique is an established method to harvest the saphenous vein (NT-SV), which is the most commonly used conduit in coronary artery bypass grafting. Herein, we summarize the foundational evidence, as well as highlight recent innovations and ongoing clinical trials involving NT-SV.

RECENT FINDINGS

Through preservation of perivascular tissue for atraumatic handling and omission of manual distension, the NT-SV maintains endothelial nitrous oxide synthase levels and experiences less vascular smooth muscle cell activation, which translates to slower progression of atherosclerosis and less size mismatch of the graft and target vessel. These biomolecular advantages allow NT-SV to provide superior graft patency compared to conventional skeletonized saphenous vein and approximating that of the radial artery. Nonetheless, the clinical benefits of NT-SV for mortality and reduction in major adverse cardiac and cerebrovascular events are insufficiently studied in the long-term. The drawback of NT-SV is the short-term harvest site complications, which may potentially be addressed by the advent of endoscopic no-touch technique.

SUMMARY

NT-SV is a promising conduit, and its role will be further clarified in upcoming clinical trials and as follow-up lengthens. However, conduit selection and harvest technique should ultimately be personalized to the individual patient.

Competitive Flow of Terminal Anastomosis to Right Coronary Territory in "Y" Coronary Artery Bypass

BACKGROUND

We evaluated the prevalence and outcomes of competitive flow in the terminal right coronary artery (RCA) graft after coronary artery bypass grafting (CABG) with left internal thoracic artery-based Y-composite grafting at 1 year after CABG.

METHODS

We enrolled 642 patients who underwent Y-composite graft-based off-pump CABG with in situ left internal thoracic artery between 2014 and 2022. All patients underwent early postoperative angiography, and 1-year postoperative angiography was performed in 81.2% (522/642) of patients.

RESULTS

The early occlusion rate of distal anastomoses with Y-composite graft was 2.1%. Competitive flow was observed in 69 of 642 anastomoses (10.7%). Multivariate analysis showed that the maximal degree of target vessel stenosis (odds ratio [OR], 0.909; 95% CI, 0.886-0.931; P < .001), maximal degree of non-terminal target vessel in Y-arm grafts (OR, 1.103; 95% CI, 1.047-1.172; P < .001), and diabetes mellitus (OR, 0.535; 95% CI, 0.303-0.934; P = .029) were factors associated with competitive flow to the RCA territory. The optimal cutoff value for the degree of terminal target vessel stenosis predicting competitive flow to the RCA territory was 92.5%. The 1-year graft failure rate of anastomoses with competitive flow of the terminal anastomosis was 30.9% (17/55). The presence of competitive flow on early angiography was the only factor associated with graft occlusion of the terminal anastomosis at 1 year (OR, 2.339; 95% CI, 1.165-4.481; P = .013).

CONCLUSIONS

For terminal anastomosis to the RCA territory in Y-composite graft-based CABG, the presence of competitive flow on early angiography was associated with graft occlusion of the terminal anastomosis at 1 year. Notably, 30.9% of these grafts demonstrated failure on 1-year follow-up angiography.

An Obligatory Role of Perivascular Adipose Tissue in Improved Saphenous Vein Graft Patency in Coronary Artery Bypass Grafting

The gold standard graft for coronary artery bypass grafting (CABG) is the internal thoracic artery (ITA), and the second recommendation is the radial artery. However, complete revascularization with arterial grafts alone is often difficult, and the saphenous vein (SV) is the most commonly used autologous graft for CABG, because it is easier to use without restriction for the length of the graft. On the other hand, the patency of SV grafts (SVGs) is poor compared with that of arterial grafts. The SVG is conventionally harvested as a distended conduit with surrounding tissue removed, a procedure that may cause vascular damage. A no-touch technique of SVG harvesting has been reported to result in improved long-term patency in CABG comparable to that when using the ITA for grafting. Possible reasons for the excellent long-term patency of no-touch SVGs are the physical support provided by preserved surrounding perivascular adipose tissue, preservation of the vascular wall structure including the vasa vasorum, and production of adipocyte-derived factors. In this review, we discuss recent strategies aimed at improving the performance of SVGs, including no-touch harvesting, minimally invasive harvesting and mechanical support using external stents.

The impact of perivascular tissue preservation on 5-year patency of saphenous vein composite grafts

OBJECTIVES

This retrospective study was conducted to evaluate the impact of saphenous vein (SV) harvesting with versus without perivascular tissue on the 5-year angiographic patency in coronary artery bypass grafting.

METHODS

Among the 944 patients who received coronary artery bypass grafting between 2010 and 2015, 579 patients who received off-pump coronary artery bypass grafting using 1 SV as a Y-composite graft based on the in situ left internal thoracic artery were enrolled. SV harvesting was performed using no-touch technique without perivascular tissue (the NoPVT group) in 342 patients and with perivascular tissue (the PVT group) in 237 patients. Follow-up duration was 84.0 months (interquartile range 66.5-105.4). Propensity score matching was performed, and long-term clinical outcomes and angiographic patency were compared.

RESULTS

The average number of distal anastomoses per patient was comparable between the groups, although more SV grafts were anastomosed to left anterior descending territory in the PVT group than in the NoPVT group. Overall survival and cumulative incidence of cardiac death were comparable between the groups, whereas cumulative incidence of target vessel revascularization (1.3% vs 4.3% at 5 year, P = 0.009) and that of major adverse cardiac events (7.3% vs 9.9% at 5 year, P = 0.035) were lower in the PVT group than in the NoPVT group. One-year and 5-year angiographic patency rates of the SV grafts were higher in the PVT group than in the NoPVT group [97.0% vs 91.7% (P = 0.004) and 96.3% vs 89.9% (P = 0.007), respectively].

CONCLUSIONS

SV grafts harvested using no-touch technique with perivascular tissue further improved the 5-year patency of SV composite grafts compared with those without perivascular tissue.

Techniques and Technologies to Improve Vein Graft Patency in Coronary Surgery

Vein grafts are the most used conduits in coronary artery bypass grafting (CABG), even though many studies have suggested their lower patency compared to arterial alternatives. We have reviewed the techniques and technologies that have been investigated over the years with the aim of improving the quality of these conduits. We found that preoperative and postoperative optimal medical therapy and no-touch harvesting techniques have the strongest evidence for optimizing vein graft patency. On the other hand, the use of venous external support, endoscopic harvesting, vein preservation solution and anastomosis, and graft configuration need further investigation. We have also analyzed strategies to treat vein graft failure: when feasible, re-doing the CABG and native vessel primary coronary intervention (PCI) are the best options, followed by percutaneous procedures targeting the failed grafts.

External stenting for saphenous vein grafts in coronary artery bypass grafting: A meta-analysis

OBJECTIVES

Autologous saphenous vein grafts (SVGs) are the most commonly used bypass conduits in coronary artery bypass grafting (CABG) with multivessel coronary artery disease. Although external support devices for SVGs have shown promising outcomes, the overall efficacy and safety remains controversial. We aimed to evaluate external stenting for SVGs in CABG versus non-stented SVGs.

METHODS

MEDLINE, EMBASE, Cochrane Library and clinicaltrails.gov were searched for randomized controlled trials (RCTs) to evaluate external-stented SVGs versus non-stented SVGs in CABG up to 31 August 2022. The risk ratio and mean difference with 95% confidence interval were analysed. The primary efficacy outcomes included intimal hyperplasia area and thickness. The secondary efficacy outcomes were graft failure (≥50% stenosis) and lumen diameter uniformity.

RESULTS

We pooled 438 patients from three RCTs. The external stented SVGs group showed significant reductions in intimal hyperplasia area (MD: -0.78, p < 0.001, I2  = 0%) and thickness (MD: -0.06, p < 0.001, I2  = 0%) compared to the non-stented SVGs group. Meanwhile, external support devices improved lumen uniformity with Fitzgibbon I classification (risk ratio (RR):1.1595, p = 0.05, I2  = 0%). SVG failure rates were not increased in the external stented SVGs group during the short follow-up period (RR: 1.14, p = 0.38, I2  = 0%). Furthermore, the incidences of mortality and major cardiac and cerebrovascular events were consistent with previous reports.

CONCLUSIONS

External support devices for SVGs significantly reduced the intimal hyperplasia area and thickness, and improved the lumen uniformity, assessed with the Fitzgibbon I classification. Meanwhile, they did not increase the overall SVG failure rate.

Graft Patency of No-Touch Saphenous Veins Used as Aortocoronary Bypass Grafts

Background

This study evaluated the early, 1-year, and 3-year graft patency rates and mid-term clinical outcomes after no-touch saphenous veins (NT-SVs) were used as aortocoronary grafts in coronary artery bypass grafting (CABG).

Methods

In total, 101 patients who underwent CABG using NT-SVs as aortocoronary grafts were included. The 2 most common indications for performing aortocoronary grafting with NT-SVs were unavailability of the left internal thoracic artery (n=36) and moderate lesions where flow competition was expected (n=27). Early (median, 1 day; interquartile range [IQR], 1-2 days), 1-year (median, 13 months; IQR, 11-16 months), and 3-year (median, 34 months; IQR, 27-41 months) graft angiography was performed in 98 (97.0%), 84 (83.2%), and 40 patients (39.6%), respectively. The median follow-up duration was 43 months (IQR, 13-76 months). Overall survival rates and the cumulative incidence of major adverse cardiac events were evaluated.

Results

The operative mortality rate was 2% (2 of 101 patients). Early postoperative patency rates for overall and aortocoronary NT-SV grafts were 98.2% (223 of 227 distal anastomoses) and 98.2% (164 of 167), respectively. The 1- and 3-year patency rates for aortocoronary SV grafts were 94.9% (131 of 138) and 90.6% (58 of 64), respectively. The overall survival rates at 5 and 10 years were 81.7% and 59%, respectively. The cumulative incidence of major adverse cardiac events at 5 and 10 postoperative years was 20.7% and 39%, respectively.

Conclusion

The feasibility of using NT-SVs as aortocoronary grafts in CABG was shown in this study, based on the graft patency rates up to 3 years and the mid-term clinical outcomes.

To touch or not to touch: unveiling the key to vein graft patency

The Graft Patency Between No-Touch Vein Harvesting Technique and Conventional Approach in Coronary Artery Bypass Graft Surgery (PATENCY) trial, a large multicenter study, compared the no-touch (NT) technique with conventional vein harvesting in coronary artery bypass graft (CABG) surgery. The study included 2655 patients and assessed graft patency at 3 months and 1 year using computed tomography (CT) angiography. The NT group showed a significantly lower occlusion rate at 3 months (2.8% vs. 4.8%) as well as at 1 year (3.7% vs. 6.5%). Recurrence of angina was also lower in the NT group at 1 year. The study provides robust evidence supporting the NT technique's efficacy in improving vein graft patency.

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

PREAMBLE

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

An unusual case of huge fibrotic sac of hematoma at saphenous vein harvest site for coronary artery bypass grafting: a case report

Great saphenous vein is a conduit commonly used for coronary artery bypass grafting. However, several complications could occur at leg wound site for vein harvesting. Here, we describe a huge sac of hematoma as an uncommon complication of saphenous vein harvest for coronary artery bypass grafting.A 62-year-old gentleman was readmitted with swelling at left thigh 30 days after coronary artery bypass grafting. Lower extremity computed tomography was suggestive of an oval and thick sac implying a hematoma or seroma. After using ultrasound scanning for the mass, an incision through the previous surgical wound showed a huge mass. Inspection after incision the mass revealed an old hematoma within the sac.Pathologic findings demonstrated chronic inflammation with the hematoma surrounded by a fibrotic sac. The patient's postoperative course was uneventful without recurrence.Our experience suggests the possibility of a huge hematoma within a thick fibrotic sac at the previous vein harvest site for coronary artery bypass grafting.

Anterolateral territory coronary artery bypass grafting strategies: a non-inferiority randomized clinical trial: the AMI-PONT trial

OBJECTIVES

The main objective was to assess whether a composite coronary artery bypass grafting strategy including a saphenous vein graft bridge to distribute left internal mammary artery outflow provides non-inferior patency rates compared to conventional grafting surgery with separated left internal mammary artery to left anterior descending coronary graft and aorto-coronary saphenous vein grafts to other anterolateral targets.

METHODS

All patients underwent isolated grafting surgery with cardiopulmonary bypass and received ≥2 grafts/patients on the anterolateral territory. The graft patency (i.e. non-occluded) was assessed using multislice spiral computed tomography at 1 year.

RESULTS

From 2012 to 2021, 208 patients were randomized to a bridge (n = 105) or conventional grafting strategy (n = 103). Patient characteristics were comparable between groups. The anterolateral graft patency was non-inferior in the composite bridge compared to conventional grafting strategy at 1 year [risk difference 0.7% (90% confidence interval -4.8 to 6.2%)]. The graft patency to the left anterior descending coronary was no different between groups (P = 0.175). Intraoperatively, the bridge group required shorter vein length for anterolateral targets (P < 0.001) and exhibited greater Doppler flow in the mammary artery pedicle (P = 0.004). The composite outcome of death, myocardial infarction or target vessel reintervention at 30 days was no different (P = 0.164).

CONCLUSIONS

Anterolateral graft patency of the composite bridge grafting strategy is non-inferior to the conventional grafting strategy at 1 year. This novel grafting strategy is safe, efficient, associated with several advantages including better mammary artery flow and shorter vein requirement, and could be a valuable alternative to conventional grafting strategies. Ten-year clinical follow-up is underway.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01585285.

Impact of Functional vs Anatomic Complete Revascularization in Coronary Artery Bypass Grafting

BACKGROUND

This study was conducted to evaluate the impact of functional and anatomic complete revascularization on long-term clinical outcomes after coronary artery bypass grafting (CABG).

METHODS

Of 2034 patients who underwent primary isolated CABG between 2006 and 2017, 1162 patients who underwent off-pump CABG for 3-vessel disease and for whom data on functional and anatomic completeness of revascularization were available on the basis of preoperative myocardial single photon emission computed tomography and early postoperative graft angiography were enrolled. The median follow-up duration was 82.4 months (interquartile range, 50.8-122.4 months). Univariate and multivariate analyses were performed to evaluate the impact of the functional and anatomic completeness of revascularization on long-term survival.

RESULTS

Of 1162 patients, anatomic complete revascularization was achieved in 1014 patients (87.3%), whereas functional complete revascularization was achieved in 1077 patients (92.7%). Early mortality occurred in 7 patients. Late death occurred in 322 of 1155 early survivors. The 5- and 10-year overall survival rates were 84.3% and 66.7%, respectively. Univariate analyses demonstrated that functional completeness of revascularization was a statistically significant risk factor (P = .038), whereas anatomic completeness was not (P = .859). The multivariate analysis showed that functional completeness of revascularization (hazard ratio, 1.54; 95% CI, 1.08-2.22; P = .019) and age, underweight status, diabetes mellitus, chronic kidney disease, chronic obstructive pulmonary disease, and left ventricular dysfunction were significant factors associated with long-term survival.

CONCLUSIONS

Functional rather than anatomic completeness of revascularization has a significant impact on the long-term survival in patients who undergo CABG.

Occurrence rate and fate of competitive flow of the left internal thoracic artery used in Y-composite grafts

Objectives

Methods

Results

Conclusions

Current intraoperative storage and handling practices of autologous bypass conduit: A survey of the royal australasian college of surgeons

During bypass surgery for peripheral arterial occlusive disease and ischaemic heart disease, autologous graft conduit including great saphenous veins and radial arteries are frequently stored in solution. Endothelial damage adversely affects the performance and patency of autologous bypass grafts, and intraoperative graft storage solutions have been shown to influence this process. The distribution of storage solutions currently used amongst Cardiothoracic and Vascular Surgeons from Australia and New Zealand is not well defined in the literature. The aim of this study was to determine current practices regarding autologous graft storage and handling amongst this cohort of surgeons, and discuss their potential relevance in the context of early graft failure. From this survey, the most frequently used storage solutions were heparinized saline for great saphenous veins, and pH-buffered solutions for radial arteries. Duration of storage was 30–45 min for almost half of respondents, although responses to this question were limited. Further research is required to investigate whether ischaemic endothelial injury generates a prothrombotic state, whether different storage media can alter this state, and whether this is directly associated with clinical outcomes of interest such as early graft failure.

Competitive Flow in Vein Composite Grafts Based on the Left Internal Thoracic Artery: Early and 1-Year Angiographic Analyses

We assessed the incidence of competitive flow with early postoperative angiograms in patients who received a "no-touch" saphenous vein (NT SV) composite graft and reexamined the status of competitive flow at 1-year. Early postoperative angiograms were performed in 806 patients who underwent myocardial revascularization using a NT SV Y-composite graft based on the in situ left internal thoracic artery (LITA). Competitive conduit flow was observed in 102 distal anastomoses (102 of 3039 [3.4%] anastomoses) of 94 patients (94 of 806 [11.7%]; NT SV competitive flow in 74 and LITA competitive flow in 20). Of the 94 patients, 63 patients (50 with NT SV competition and 13 with LITA competition) were re-evaluated with 1-year postoperative angiograms. Fifty-six competitive NT SV conduits in 50 patients were reevaluated at 1-year postoperatively: 44 (78.6%) early competitive anastomoses had become patent and 12 (21.4%) were occluded. NT SV with pedicle tissue showed a higher tendency of being perfectly patent at 1-year postoperatively than NT SV without pedicle tissue (17 of 40 [42.5%] vs 2 of 16 [12.5%]; P = 0.007). Thirteen competitive LITA conduit anastomoses in 13 patients were reevaluated 1-year postoperatively: 9 (69.2%) early competitive anastomoses had become patent and 4 (30.8%) were occluded. Competitive flow was shown on early postoperative angiograms in 3.4% of distal anastomoses in patients who received NT SV Y-composite grafts. Approximately 80% of the competitive NT SV conduits were patent 1-year postoperatively, and perfect patency rates were higher in patients who had received NT SV with pedicle tissue than in patients who had received NT SV without pedicle tissue.

A five-parameter score for predicting saphenous vein graft degenerative and/or occlusive disease in recurring ischemic symptoms after one year post coronary artery bypass grafting

BACKGROUND

The recurrence rate of ischemic symptoms after coronary artery bypass grafting (CABG) is increasing in recent years. How to prevent and treat saphenous vein graft disease (SVGD [symptomatic ⩾50% stenosis in at least one Saphenous vein graft]) has been a clinical challenge to date. Different pathogenesis may exist in SVGD of different periods. There are currently few available scores for estimating the risk of SVGD after one year post CABG.

OBJECTIVE

We sought to develop and validate a simple predictive clinical risk score for SVGD with recurring ischemia after one year post CABG.

METHODS AND RESULTS

This was a cross-sectional study and the results were validated using bootstrap resampling on a separate cohort. A nomogram and risk scoring system were developed based on retrospective data from a training cohort of 606 consecutive patients with recurring ischemia >1 year after CABG. Logistic regression model was used to find the predictive factors and to build a nomogram. To assess the generalization, models were validated using bootstrap resampling and an external cross-sectional study of 187 consecutive patients in four other hospitals. In multivariable analysis of the primary cohort, native lesion vessel number, SVG age, recurring ischemia type, very low-density lipoprotein level, and left ventricular end-diastolic diameter were independent predictors. A summary risk score was derived from nomogram, with a cut-off value of 15. In internal and external validation, the C-index was 0.86 and 0.82, indicating good discrimination. The calibration curve for probability of SVGD showed optimal agreement between actual observations and risk score prediction.

CONCLUSION

A simple-to-use risk scoring system based on five easily variables was developed and validated to predict the risk of SVGD among patients who recurring ischemia after one year post CABG. This score may be useful for providing patients with individualized estimates of SVGD risk.

Short-Term Evaluation of a Novel No-Touch Technique for Harvesting Saphenous Veins With Long-Shafted Ultrasonic Scalpel

OBJECTIVE

Saphenous vein grafts (SVGs) are widely used as bypass conduits in coronary artery bypass grafting. Compared with the conventional technique, the "no-touch" technique, wherein the saphenous veins are harvested with the surrounding tissue, may improve SVG patency; however, there are concerns regarding wound complications. To address this issue, we describe our novel no-touch technique with separate skin incisions using a long-shafted ultrasonic scalpel and report the clinical outcomes.

METHODS

We enrolled 66 male patients who underwent isolated coronary artery bypass grafting between April 2016 and April 2021. There were 30 and 36 patients treated using our no-touch technique and the conventional technique, respectively. The participants underwent coronary angiography before discharge and were followed clinically. SVG samples were taken for pathological examination.

RESULTS

SVGs harvested using our no-touch technique displayed preservation of the vessel wall structure and surrounding tissues. Our no-touch technique demonstrated no inferiority in patency compared with the conventional technique, and there was no SVG occlusion in the no-touch group. The frequency of leg wound complications was higher in the no-touch group than the conventional group, but no surgical site infections and severe complications occurred in the no-touch group.

CONCLUSIONS

SVGs harvested using our novel no-touch technique had similar pathological characteristics to those harvested using the original no-touch technique reported previously. Our no-touch technique maintained SVG patency and caused no severe wound complications. However, a large-scale, longitudinal study is required to accurately assess the clinical outcomes of our no-touch technique.

Acute shear stress and vein graft disease

The long saphenous vein is commonly used in cardiac surgery to bypass occluded coronary arteries. Its use is complicated by late stenosis and occlusion due to the development of intimal hyperplasia. It is accepted that intimal hyperplasia is a multifactorial inflammatory process that starts immediately after surgery. The role of acute changes in haemodynamic conditions when the vein is implanted into arterial circulation, especially shear stress, is not fully appreciated. This review provides an overview of intimal hyperplasia and the effect of acute shear stress changes on the activation of pro-inflammatory mediators.

No-Touch Sequential Saphenous Venous Harvesting Technique in Off-Pump Bypass Surgery: A Retrospective Study

Background

In the mid-1990s, the Swedish expert team proposed saphenous vein graft (SVG) harvesting with pedicle tissue. The short-term and long-term patency rates of the great saphenous vein obtained by the no-touch (NT) were higher than those obtained by the conventional (CON). In the past, NT harvesting was mainly used in on-pump coronary artery bypass grafting (CABG), and vein grafts were mostly single vein grafts. In this study, we retrospectively analyzed the safety and effectiveness of sequential vein grafts using NT harvesting in off-pump CABG.

Methods

From 2017 to 2019, a total of 505 patients were included in the study. There were 150 patients in the NT group and 355 patients in the CON group. After applying propensity score matching (1:1 matching), 148 patients were included in each group. Baseline data, graft patency, post-operative complications, leg wound complications and 1-year major adverse cardiac and cerebrovascular events (MACCEs) were compared between the two groups.

Results

There was no significant difference in the patency rate of sequential venous grafts between the two groups 1 year after the operation either before [NT: 7.1% (10/141) vs. CON: 11.5% (38/331), p = 0.149) or after matching (NT: 7.1% (10/140) vs. CON: 7.3% (9/124), p = 0.971]. There was no significant difference in the composite clinical endpoint between the two groups either before [NT: 3 (2.3%) vs. CON: 9 (2.8%), p = 1.000] or after matching [NT: 3 (2.3%) vs. CON: 3 (2.5%), p = 1.000]. There were differences in leg wound complications between the two groups both before [NT: 9 (6.9%) vs. CON: 6 (1.9%), p = 0.007] and after matching [NT: 9 (6.9%) vs. CON: 2 (1.7%), p = 0.043].

Conclusions

The application of the NT harvesting in off-pump CABG with sequential vein grafts is safe and effective. NT method has disadvantages in leg wound.

Harvesting techniques of the saphenous vein graft for coronary artery bypass: Insights from a network meta-analysis

OBJECTIVE

The optimal harvesting technique of saphenous vein (SVG) in coronary artery bypass grafting (CABG) is still to be elucidated. The present study aimed to compare the methods of SVG harvesting technique, which were open vein harvesting (OVH), endoscopic vein harvesting (EVH), and no-touch vein harvesting (NT), using a network meta-analysis of randomized controlled trials (RCTs), and propensity-score matched (PSM) studies.

METHODS

MEDLINE and EMBASE were searched through April 2021 to identify RCTs and PSM studies that investigated the outcomes in patients who underwent CABG with the SVG using one of three methods; OVH, EVH, and NT. The outcomes of interest were all-cause mortality, the rates of revascularization, and graft failure. Risk ratios (RRs) were extracted for the rates of graft failure, and hazard ratios (HRs) were extracted for all-cause mortality and the rates of revascularization.

RESULTS

Eligible seven RCT and five PSM studies were identified which enrolled a total of 8111 patients. All-cause mortality was significantly lower in patients with EVH compared with OVH (HR [95% confidence interval (CI)] =0.77 [0.65-0.92], p = .0032). The rates of revascularization were similar among the groups. The rate of graft failures was significantly lower in patients with NT compared with OVH (HR [95% CI] =0.54 [0.32-0.90], p = .019) and with EVH (HR [95% CI] =0.39 [0.17-0.86], p = .023).

CONCLUSION

NT vein harvesting is favorable for graft patency, and OVH showed higher all-cause mortality than EVH. Further well-powered RCTs are needed to confirm our findings.

Reopening of the occluded saphenous vein composite grafts after coronary artery bypass grafting

BACKGROUND

We have observed reopening of the occluded "no-touch" saphenous vein (NT SV) composite grafts on follow-up angiograms in patients who underwent coronary artery bypass graftings (CABGs).

METHODS

Between 2008 and 2018, 1283 patients received NT SV conduits without or with surrounding pedicle tissue as composite grafts based on the in situ left internal thoracic artery (ITA) for CABG and underwent early postoperative angiographies. Among the 1283 patients, 53 patients showed 55 occluded SV conduit anastomoses, and 46 patients who had 48 occluded SV anastomoses were re-evaluated by 1-year postoperative angiographies.

RESULTS

Early postoperative angiographies in 1283 patients demonstrated overall occlusion rates of 1.2% (56/4518); occlusion rates of the ITA and SV were 0.08% (1/1259) and 1.7% (55/3260), respectively. One-year angiograms demonstrated that 14 occluded SV anastomoses (29.2% [14/48 occluded SV]) of 14 patients became patent. Reopening of occluded SV conduits occurred more frequently in NT SV with pedicle tissue than in NT SV without pedicle tissue (45.0% [9/20] vs. 17.9% [5/28]; p = .057). When we examined the preoperative and 1-year postoperative angiograms, reopening of the occluded SV conduits was not related with progression (p = .258) or preoperative reversibility score (p = .115) of native target coronary artery disease.

CONCLUSIONS

More than a quarter of the occluded SV composite grafts on early postoperative angiograms were patent in the 1-year angiograms. The reopening rates were higher in patients who had received NT SV conduits with pedicle tissue than those who had received NT SV conduits without pedicle tissue.

Five-year patency for the no-touch saphenous vein and the left internal thoracic artery in on- and off-pump coronary artery bypass grafting

BACKGROUND

Randomized trials show high long-term patency for no-touch saphenous vein grafts in coronary artery bypass grafting. The patency rate in off-pump coronary bypass surgery for these grafts has not been investigated. Our center participated in the CORONARY randomized trial, NCT00463294. This is a study aimed to assess the patency of no-touch saphenous veins in on- versus off-pump coronary bypass surgery at five-year follow-up.

METHODS

Fifty-six patients were included. Forty of 49 patients, alive at 5 years, participated in this follow-up. There were 21 and 19 patients in the on- and off-pump groups respectively. No-touch saphenous veins were used to bypass all targets and in some cases the left anterior descending artery. Graft patency according to distal anastomosis was evaluated with computed tomography angiography.

RESULTS

The five-year patency rate was 123/139 (88.5%). The patency for the no-touch vein grafts was 57/64 (89.1%) in the on-pump versus 37/45 (82.2%) in the off-pump group. All left internal thoracic arteries except for one, 29/30 (96.6%), were patent. All vein grafts used to bypass the left anterior descending and the diagonal arteries were patent 32/32. The lowest patency rate for the saphenous veins was to the right coronary territory, particularly in off-pump surgery (80.0% vs. 62.5% for the on- respective off-pump groups).

CONCLUSIONS

Comparable 5-year patency for the no-touch saphenous veins and the left internal thoracic arteries to the left anterior descending territory in both on- and off-pump coronary artery bypass grafting. Graft patency in off-pump CABG is lower to the right coronary artery.

The Short-Term Patency Rate of a Saphenous Vein Bridge Using the No-Touch Technique in off-Pump Coronary Artery Bypass Grafting in Vein Harvesting

Objective

This study aimed to examine the short-term effect of the no-touch technique on the patency rate of a great saphenous vein (GSV) bridge used during off-pump coronary artery bypass grafting (OPCABG).

Methods

Between June 2018 and September 2020, 140 patients undergoing OPCABG, with grafts obtained from the GSV using the "no-touch" technique or the left internal mammary artery (LIMA), were enrolled in this study. The early clinical results and short-term patency rate of the OPCABG were evaluated at a three-month follow-up by comparing the patency rate of the LIMA bridge and the GSV bridge obtained by the no-touch technique. This study also analyzed the impacts of the postoperative complications of the lower limbs and the distribution area of diseased vessels on the patency rate of a GSV bridge obtained by the no-touch technique at an early stage.

Results

No perioperative death or adverse cardiovascular or cerebrovascular events occurred in the 140 patients undergoing OPCABG. The difference in the early patency rate between the GSV bridge obtained by the no-touch technique and the LIMA bridge was not statistically significant (95.9% vs 97.1%, p = 0.501). There was no significant difference in the patency rate between an end-to-side anastomosed venous bridge and a LIMA bridge (95.0% [248/261] vs 97.1% [136/140], p = 0.314). The overall patency rate of a no-touch vein bridge in the right coronary artery region was lower than it was in the left coronary artery region (93.8% [165/176] vs 97.9% [183/187], p = 0.049).

Conclusion

The no-touch technique may improve the early patency rate of a GSV bridge, and its effect is similar to that of a LIMA bridge.

Relation between functional coronary artery stenosis and graft occlusion after coronary artery bypass grafting

OBJECTIVES

This study was conducted to evaluate graft patency rates during the 5 years after coronary artery bypass grafting according to the functional significance of the coronary artery stenosis, as determined by myocardial single-photon-emission computed tomography.

METHODS

Two hundred ninety-five patients who underwent coronary artery bypass grafting using Y-composite grafts based on the in situ left internal thoracic artery, and in whom preoperative stress/rest myocardial single-photon-emission computed tomography and 1-year angiographies were available were enrolled. Seven hundred sixty-nine and 262 distal anastomoses were constructed to ischemic and nonischemic areas, respectively. One-year and 5-year angiographic occlusion rates were evaluated in all and 80.3% of study patients, respectively. Factors associated with graft occlusion were evaluated using generalized linear mixed-effects models.

RESULTS

Overall 1- and 5-year graft occlusion rates were 4.3% (44 of 1031 distal anastomoses) and 5.5% (45 out of 820), respectively. The occlusion rates of grafts bypassed to vessels with functionally significant and insignificant stenosis were 2.7% (21 out of 769) and 8.8% (23 out of 262) at 1 year and were 4.0% (25 out of 618) and 9.9% (20 out of 202) at 5 years, respectively. Graft occlusion during the 5 years after coronary artery bypass grafting was associated with the functional significance of coronary artery stenosis (odds ratio, 0.50; 95% confidence interval, 0.28-0.92). The odds ratio of the graft occlusion according to functional ischemia was lower and significant in grafts to arteries with intermediate stenosis (stenosis ≥70% but <90%; odds ratio, 0.34; 95% confidence interval, 0.13-0.93) whereas it was higher and insignificant in grafts to arteries with severe stenosis (≥90% stenosis; odds ratio, 0.76; 95% confidence interval, 0.33-1.72).

CONCLUSIONS

Graft occlusion during the 5 years after coronary artery bypass grafting was associated with the functional significance of coronary artery stenosis, particularly when the stenosis degree was not severe.

Outcomes of left internal mammary artery with saphenous vein composite graft to bypass the left anterior descending artery: a propensity-matched study

Background

This study aimed to evaluate the early and mid-term outcomes of a novel strategy of using the in-situ left internal mammary artery (LIMA) with the great saphenous vein graft (SVG) to bypass the left anterior descending artery (LAD) in coronary artery bypass grafting (CABG).

Methods

A total of 979 patients took part in this retrospective observational study; 83 patients were propensity-score matched to the LIMA + SVG group and 83 to the LIMA − LAD group. Early mortality, postoperative complications, mid-term major adverse cardiovascular and cerebrovascular events (MACCE) were compared among the two matched groups after the procedure.

Results

No significant differences in early mortality and postoperative complications rates were detected between the two matched groups. For mid-term outcomes, the incidence of MACCE was slightly higher in the LIMA + SVG group, but there was no significant statistical difference (14.9% vs. 12.8%, hazard ratio =1.20, 95% CI, 0.24 to 7.95; P=0.70) between the matched groups. Computed tomography coronary artery angiography (CTCA) images showed a LIMA + SVG composite graft patency rate of 94% (32/34) 25 months after the procedure.

Conclusions

Using the in situ LIMA with SVG to revascularize LAD was associated with comparable early and mid-term outcomes. These findings may provide an alternative emergency strategy when in situ LIMA cannot bypass LAD. Further study needs to be conducted to test longer-term outcomes.

[Feasibility and safety of minimally invasive cardiac coronary artery bypass grafting surgery for patients with multivessel coronary artery disease: Early outcome and short-mid-term follow up results]

OBJECTIVE

To explore the feasibility, safety and mid-term outcome of minimally invasive cardiac surgery coronary artery bypass grafting (MICS CABG) surgery.

METHODS

Data of patients who underwent MICS CABG between November 2015 and November 2017 in Peking University Third Hospital were retrospectively analyzed. Results were compared with the patients who underwent off-pump coronary aortic bypass grafting (OPCABG) surgery over the same period. The two groups were matched in propensity score matching method according to age, gender, left ventricular ejection fraction, body mass index, severity of coronary artery disease, smoking, diabetes mellitus, hypertension, hyperlipidemia, renal insufficiency, history of cerebrovascular accident, and history of chronic obstructive pulmonary disease (COPD).

RESULTS

There were 85 patients in MICS CABG group, including 68 males (80.0%) and 17 females (20%), with an average age of (63.8±8.7) years; 451 patients were enrolled in OPCABG group, and 85 patients were matched by propensity score as control group (OPCABG group). There was no significant difference in general clinical characteristics (P>0.05). The average grafts of MICS CABG and OPCABG were 2.35±0.83 and 2.48±0.72 respectively (P=0.284). No conversion to thoracotomy in MICS CABG group or cardiopulmonary bypass in neither group occurred. There was no significant difference in the major adverse cardiovascular events (MACCEs, 1.17% vs. 3.52%), reoperation (2.34 vs. 3.52%), new-onset atrial fibrillation rate (4.70% vs. 3.52%) or new-onset renal insufficiency rate (1.17% vs. 0%) between MICS CABG group and OPCABG group (P>0.05). The operation time in MICS CABG group was longer than that in OPCABG group [(282.8±55.8) min vs. (246.8±56.9) min, P < 0.05], while the time of ventilator supporting(16.9 h vs. 29.6 h), hospitalization in ICU [(29.3±20.8) h vs. (51.5±48.3) h] and total hospitalization [(18.3±3.2) d vs. (25.7±4.2) d] in MICS CABG group were shorter than those in OPCABG group (P < 0.05). The total patency rate (A+B levels) of MICS CABG was 96.5% after surgery. There was no significant difference in MACCEs rate between the two groups [1.18%(1/85) vs. 3.61%(3/83), P>0.05] in 1-year follow up.

CONCLUSION

The MICS CABG surgery is a safe and feasible procedure with good clinical results in early and mid-term follow-up.

Impact of Atherogenic Indexes in Saphenous Vein Graft Stenosis

Fundamento

Os enxertos de veias safenas (EVS) são frequentemente usados em pacientes submetidos a cirurgia de revascularização do miocárdio (CRM).

Objetivos

Avaliar as relações entre índices aterogênicos e estenose de EVS. Métodos: No total, 534 pacientes (27,7% mulheres, com idade média de 65±8,4 anos) submetidos a CRM e angiografia coronariana eletiva foram incluídos no estudo. Pacientes com pelo menos uma estenose EVS ≥50% foram alocados ao grupo estenose EVS (+) (n=259) e pacientes sem estenose foram classificados como EVS (-) (n=275). O índice aterogênico plasmático (IAP) e o coeficiente aterogênico (CA) foram calculados a partir dos parâmetros lipídicos de rotina dos pacientes. A significância foi estabelecida no nível p<0,05.

Resultados

O número de pacientes com histórico de hipertensão (HT), diabetes mellitus (DM), acidente vascular cerebral e insuficiência cardíaca (IC) se mostrou significativamente maior no grupo EVS (+) do que no grupo EVS (-). O colesterol total, triglicerídeos e colesterol LDL mostraram-se significativamente mais altos e o colesterol HDL mostrou-se menor no grupo EVS (+) do que no grupo EVS (-). IAP (p<0,001) e CA (p<0,001) apresentaram-se significativamente mais altos no grupo EVS (+) do que no grupo EVS (-). A análise ROC mostra que tanto o IAP quanto o CA mostraram-se melhores que o colesterol HDL, colesterol LDL e colesterol não HDL na predição de estenose de EVS. Na análise multivariada, histórico de DM, HT, acidente vascular cerebral, IC, número de enxertos de safena, colesterol HDL, colesterol LDL, colesterol não HDL, IAP e CA foram fatores de risco independentes para estenose de EVS.

Conclusão

O IAP e o CA foram preditores independentes de estenose de EVS. Além disso, tanto o IAP quanto o CA têm melhor desempenho na predição de estenose de EVS do que o colesterol LDL, colesterol HDL e colesterol não HDL. (Arq Bras Cardiol. 2020; 115(3):538-544)

Development of a risk score for early saphenous vein graft failure: An individual patient data meta-analysis

OBJECTIVES

Early saphenous vein graft (SVG) occlusion is typically attributed to technical factors. We aimed at exploring clinical, anatomical, and operative factors associated with the risk of early SVG occlusion (within 12 months postsurgery).

METHODS

Published literature in MEDLINE was searched for studies reporting the incidence of early SVG occlusion. Individual patient data (IPD) on early SVG occlusion were used from the SAFINOUS-CABG Consortium. A derivation (n = 1492 patients) and validation (n = 372 patients) cohort were used for model training (with 10-fold cross-validation) and external validation respectively.

RESULTS

In aggregate data meta-analysis (48 studies, 41,530 SVGs) the pooled estimate for early SVG occlusion was 11%. The developed IPD model for early SVG occlusion, which included clinical, anatomical, and operative characteristics (age, sex, dyslipidemia, diabetes mellitus, smoking, serum creatinine, endoscopic vein harvesting, use of complex grafts, grafted target vessel, and number of SVGs), had good performance in the derivation (c-index = 0.744; 95% confidence interval [CI], 0.701-0.774) and validation cohort (c-index = 0.734; 95% CI, 0.659-0.809). Based on this model. we constructed a simplified 12-variable risk score system (SAFINOUS score) with good performance for early SVG occlusion (c-index = 0.700, 95% CI, 0.684-0.716).

CONCLUSIONS

From a large international IPD collaboration, we developed a novel risk score to assess the individualized risk for early SVG occlusion. The SAFINOUS risk score could be used to identify patients that are more likely to benefit from aggressive treatment strategies.

The clinical application of microincision vein harvesting of the great saphenous vein in coronary artery bypass grafting

BACKGROUND

The present study aimed to summarize the clinical application of microincision vein harvesting (MVH) of the great saphenous vein in coronary artery bypass grafting (CABG).

METHODS

From July 2014 to October 2017, 160 patients underwent coronary artery bypass grafting. Among them, 80 patients received MVH of the great saphenous vein, and 80 received open venous harvesting (OVH). The results of the sampling operation, complications during hospitalization, and the long-term patency of the great saphenous vein were compared between the two groups.

RESULTS

All the patients in both groups received successful operations. The difference in the length of the veins obtained and the injury of the veins was not statistically significant (P > 0.05). The difference in the long-term patency rate of the graft vessels between the two groups was not statistically significant. The in-hospital mortality rate was the same in both groups. The MVH group had noticeable advantages over the OVH group in terms of the vein collection times, the incision length, and the complications experienced when performing the leg incisions (P < 0.01). The time relating to the patients' observed early out-of-bed activity was significantly longer in the MVH group. Furthermore, the patients' hospitalization length was significantly shorter in the MVH group compared to the OVH group (P < 0.05). The MVH group had significant advantages in pain score and patient satisfaction, and this difference was also statistically significant (P < 0.05).

CONCLUSIONS

The MVH procedure met the requirements of CABG in vein grafting. When compared with OVH, MVH can significantly reduce leg incision complications and improve patients' overall satisfaction with their hospital experience.

Saphenous vein graft disease, pathophysiology, prevention, and treatment. A review of the literature

BACKGROUND

The saphenous vein remains the most frequently used conduit for coronary artery bypass grafting, despite reported unsatisfactory long-term patency rates. Understanding the pathophysiology of vein graft failure and attempting to improve its longevity has been a significant area of research for more than three decades. This article aims to review the current understanding of the pathophysiology and potential new intervention strategies.

METHODS

A search of three databases: MEDLINE, Web of Science, and Cochrane Library, was undertaken for the terms "pathophysiology," "prevention," and "treatment" plus the term "vein graft failure."

RESULTS

Saphenous graft failure is commonly the consequence of four different pathophysiological mechanisms, early acute thrombosis, vascular inflammation, intimal hyperplasia, and late accelerated atherosclerosis. Different methods have been proposed to inhibit or attenuate these pathological processes including modified surgical technique, topical pretreatment, external graft support, and postoperative pharmacological interventions. Once graft failure occurs, the available treatments are either surgical reintervention, angioplasty, or conservative medical management reserved for patients not eligible for either procedure.

CONCLUSION

Despite the extensive amount of research performed, the pathophysiology of saphenous vein graft is still not completely understood. Surgical and pharmacological interventions have improved early patency and different strategies for prevention seem to offer some hope in improving long-term patency.

Stable Hemodynamics within "No-Touch" Saphenous Vein Graft

PURPOSE

To investigate the hemodynamics characteristics of the "no-touch" saphenous vein graft (SVG) conduits by nicardipine intraluminal administration in vivo experiment.

METHODS

A total of 59 consecutive patients were enrolled and underwent a sequential SVG to three non-left anterior descending (LAD) targets with the average runoff ≤2 mm, 30 with "no-touch" harvest technique (group A) and 29 with conventional preparation (group B). The patients were subject to nicardipine intraluminal injection during off-pump coronary artery bypass grafting (CABG) procedure. The intraoperative flow was measured with the ultrasonic transit time flow meter (TTFM), and the graft patency testified by multi-detector computed tomography (MDCT) angiography, respectively.

RESULTS

The baseline blood flow was higher in group A than that in group B (p <0.05). However, the increases in blood flow of SVG conduits in group A were lower than those in group B with 19.7 ± 5.9 vs. 35.4 ± 9.2 mL/min, 14.8 ± 5.6 vs. 23.1 ± 6.8 mL/min, 6.6 ± 2.1 vs. 11.2 ± 4.3 mL/min before the first, second, and third anastomose after nicardipine intraluminal administration, respectively (all p <0.01).

CONCLUSIONS

No-touch SVGs were associated with higher baseline blood flow and less rises after nicardipine intraluminal administration during off-pump CABG procedure compared with conventional preparation. The no-touch SVGs seemed to be less spastic and well-tolerated on flow dilatation.

Twenty-Year Experience With Off-Pump Coronary Artery Bypass Grafting and Early Postoperative Angiography

BACKGROUND

We have performed off-pump coronary artery bypass grafting and also performed early postoperative angiography to assess anastomosis accuracy and patency in most of our patients requiring surgical revascularization.

METHODS

Of 3083 patients who underwent isolated coronary artery bypass grafting between 1998 and 2017, 2919 patients (94.7%) underwent off-pump coronary artery bypass grafting. Conduits for distal anastomoses were left internal thoracic artery (n = 2764), right internal thoracic artery (n = 866), right gastroepiploic artery (n = 997), radial artery (n = 16), and saphenous vein (n = 1505). Since the introduction of transit-time flow measurement in 2000, we revised abnormal grafts intraoperatively. Early (≤7 days) angiography was performed in 2820 patients (96.6%) at 1.5 ± 1.2 postoperative days, and surgical intervention was performed based on angiographic findings.

RESULTS

Operative mortality was 1.1% (32 of 2919). Average number of distal anastomoses was 3.2 ± 1.0. Intraoperative flowmetry-guided revision for distal anastomosis failures was performed in 109 of 8585 distal anastomoses (1.3%). Angiography showed an overall patency of 98.2% (8836 of 9001): 99.0% (5484 of 5540) for arterial and 96.9% (3352 of 3461) for venous conduits (P < .001). Patency of venous conduits was 87.2% (231 of 265) for free grafts and 97.7% (3121 of 3196) for composite grafts (P = .001). After the introduction of transit-time flow measurement, patency of arterial conduits became significantly higher (97.2% vs 99.2%; P = .038); however, patency of free venous conduits was not significantly improved (86.0% vs 91.4%; P = .181). Early re-intervention according to angiographic findings was performed in 76 patients (2.7%). Reevaluation of graft patency before discharge in 31 who underwent revision of distal anastomoses showed improved patency (65.1% [56 of 86] vs 95.3% [82 of 86]; P < .001).

CONCLUSIONS

Intraoperative flowmetry and revision of abnormal grafts improved early arterial graft patency, and reoperation based on early angiographic findings may further improve graft patency at the time of discharge.

SUPERIOR SVG: no touch saphenous harvesting to improve patency following coronary bypass grafting (a multi-Centre randomized control trial, NCT01047449)

BACKGROUND

Single centre studies support No Touch (NT) saphenous vein graft (SVG) harvesting technique. The primary objective of the SUPERIOR SVG study was to determine whether NT versus conventional (CON) SVG harvesting was associated with improved SVG patency 1 year after coronary artery bypass grafting surgery (CABG).

METHODS

Adults undergoing isolated CABG with at least 1 SVG were eligible. CT angiography was performed 1-year post CABG. Leg adverse events were assessed with a questionnaire. A systematic review was performed for published NT graft patency studies and results aggregated including the SUPERIOR study results.

RESULTS

Two hundred and-fifty patients were randomized across 12-centres (NT 127 versus CON 123 patients). The primary outcome (study SVG occlusion or cardiovascular (CV) death) was not significantly different in NT versus CON (NT: 7/127 (5.5%), CON 13/123 (10.6%), p = 0.15). Similarly, the proportion of study SVGs with significant stenosis or total occlusion was not significantly different between groups (NT: 8/102 (7.8%), CON: 16/107 (15.0%), p = 0.11). Vein harvest site infection was more common in the NT patients 1 month postoperatively (23.3% vs 9.5%, p < 0.01). Including this study's results, in a meta-analysis, NT was associated with a significant reduction in SVG occlusion, Odds Ratio 0.49, 95% Confidence Interval 0.29-0.82, p = 0.007 in 3 randomized and 1 observational study at 1 year postoperatively.

CONCLUSIONS

The NT technique was not associated with improved patency of SVGs at 1-year following CABG while early vein harvest infection was increased. The aggregated data is supportive of an important reduction of SVG occlusion at 1 year with NT harvesting.

TRIAL REGISTRATION

NCT01047449 .