Anastomosis In Coronary Artery Bypass Grafting Research Articles

Peroperative epicardial ultrasonography of distal coronary artery bypass graft anastomoses using a stabilizing device. A feasibility study

BackgroundWidespread use of intraoperative epicardial ultrasonography (ECUS) for quality assessment of coronary artery bypass graft anastomoses during coronary artery bypass grafting (CABG) has not occurred - presumably due to technological and practical challenges including the need to maintain stable and optimal acoustic contact between the ultrasound probe and the target without the risk of distorting the anastomosis. We investigated the feasibility of using a stabilizing device during ultrasound imaging of distal coronary bypass graft anastomoses in patients undergoing on-pump CABG. Imaging was performed in both the longitudinal and transverse planes.MethodsSingle-centre, observational prospective feasibility study among 51 patients undergoing elective, isolated on-pump CABG. Ultrasonography of peripheral coronary bypass anastomoses was performed using a stabilizing device upon which the ultrasound transducer was connected. Transit-time flow measurement (TTFM) was also performed. Descriptive statistical tests were used.ResultsLongitudinal and transverse images from the heel, middle and toe were obtained from 134 of 155 coronary anastomoses (86.5%). After the learning curve (15 patients), all six projections were obtained from 100 of 108 anastomoses scanned (93%). Failure to obtain images were typical due to a sequential curved graft with anastomoses that could not be contained in the straight cavity of the stabilizing device, echo artefacts from a Titanium clip located in the roof of the anastomoses, and challenges in interpreting the images during the learning curve. No complications were associated with the ECUS procedure. The combined ECUS and TTFM resulted in immediate revision of five peripheral anastomoses.ConclusionsPeroperative use of a stabilizing device during ultrasonography of coronary artery bypass anastomoses in on-pump surgery facilitates imaging and provides surgeons with non-deformed longitudinal and transverse images of all parts of the anastomoses in all coronary territories. Peroperative ECUS in addition to flow measurements has the potential to increase the likelihood of detecting technical errors in constructed anastomoses.Trial registrationThe study was registered on September 29, 2016, ClinicalTrials.gov ID: NCT02919124.

A case report on epicardial ultrasonography of coronary anastomoses using a stabilizing device without the use of ultrasound gel

BackgroundIntraoperative epicardial ultrasonography of coronary artery bypass graft anastomoses is a procedure used for anatomical quality assessment of peripheral anastomoses during coronary artery bypass grafting. However, it may be difficult to keep the ultrasound transducer in steady contact with the anastomoses on the beating heart without causing any deformation. Furthermore, we are not aware of any sterile ultrasound gel approved for application into the pericardial space.Case presentationWe report a method using a stabilizing connecting device for an ultrasound transducer to be used for visualization of coronary anastomoses without application of ultrasound gel during on-pump coronary bypass surgery.ConclusionUse of a stabilizing device and coagulated blood from the patient as an alternative for ultrasound gel facilitates peroperative ultrasonography of coronary anastomoses. The procedure provides surgeons with non-deformed echocardiographic longitudinal and transverse images of all parts of the anastomoses.Trial registrationThe patient participated in a still ongoing clinical feasibility study: Trial registration: ClinicalTrials.gov ID: NCT02919124; Registered September 29, 2016.

A Novel Method for Auto-Suturing in Laparoscopic Robotic-Assisted Coronary Artery Bypass Graft (CABG) Anastomosis

Coronary Heart Disease (CHD), which results from buildup of plaque in the heart’s coronary arteries, accounts for 12.2% of all deaths worldwide. There are two major ways to treat CHD: if the plaque level is high (above ~70% blockage), then open-heart surgery is usually performed. However, if the plaque level is moderate (~40% to 70%), then a drug-eluting stent can be placed in the artery to hold the plaque back from interfering with the blood flow and reduce restenosis. Laparoscopic heart surgery, or heart surgery conducted through small holes made between the ribs and on the sides of the chest, has increasingly been used over traditional coronary artery bypass graft (CABG) surgery, however, laparoscopic robotic-assisted CABG surgery has shown many advantages in research over both. Despite improvements, these traditional operations still take vast amounts of time and can result in infection or other complications. In this study, we developed auto-sutures that are automated through the use of a helical suture needle. Due to the significant decrease of time to suture, we increased the amount of sutures per segment of the auto-sutured CABG anastomosis. The quality of the auto-sutures was tested in a tensile test as well as a burst test apparatuses designed for this research. A burst test was simulated by pumping a blood-mimicking solution into silicon tubing. In all 80 experiments conducted (40 tensile test & 40 burst test), five sutures per segment was the optimal suturing method, as it had the highest maximum pressure as well as second-highest tensile strength.

INTRAOPERATIVE FLOWMETRY FOR GRAFT ASSESSMENT IN CORONARY ARTERY BYPASS GRAFTING. OUR EXPERIENCE

Introduction: Cardiovascular diseases and coronary artery disease (CAD) in particular are the leading causes of death all around the world. At presence, coronary artery bypass grafting (CABG) is one of the most common cardiac operations worldwide. Material and methods: During a three-year period (between 2014 and 2016), a total of 761 CAD patients hospitalized in the Department of Cardiac Surgery, St. Marina University Hospital of Varna underwent CABG surgery. In 64 patients, several transit time flowmetry (TTFM) parameters were assessed. A total of 161 grafts, 125 arterial, 58 in off-pump (OPCAB) and 67 in on-pump CABG as well as 36 venous conduits, 18 in both OPCAB and CABG each were carried out. Results: In arterial grafts, mean flow was of 30.7±23.8 mL/min and mean pulsatile index (PI) was of 2.8±1.1 while in venous ones, the mean flow was of 30.9±19.3 mL/min and the mean PI of 2.5±0.9. The corresponding figures in OPCAB and CABG were 28.8±13.8 mL/min and 2.9±1.04 as well as 36.3±0.3 mL/min and 2.4±0.1, respectively. There were two lethal cases due to cardiogenic shock. TTFM assessment of conduit patency identified that only 3.7% of the anastomoses were at risk for postoperative failure. Conclusion : TTFM is a simple, easy and rapid diagnostic method which allows for immediate and precise objective evaluation of the status of the graft anastomosis in CABG and OPCAB.

Two Cases of Percutaneous Intervention for Coronary Artery Bypass Graft Anastomoses With Paclitaxel-Eluting Balloon Catheters

Coronary artery bypass graft (CABG) intervention, particularly anastomosis site intervention, is challenging for interventional cardiologists. A paclitaxel-eluting balloon catheter (SeQuent Please) is a recently-introduced device capable of delivering paclitaxel homogeneously into the targeted vessel wall. We herein report our experience with two cases. In the first case, coronary angiography showed significant stenosis at the site of anastomosis between the saphenous vein graft and the left anterior descending artery (LAD). In the second case, coronary angiography showed significant stenosis at the site of anastomosis between the left internal mammary artery and the LAD. We performed percutaneous intervention of these CABG anastomoses using paclitaxel-eluting balloon catheters, and obtained favorable angiographic and clinical outcomes.

Relative spatial distributions of coronary artery bypass graft insertion and acute thrombosis: A model for protection from acute myocardial infarction

Randomized trials have demonstrated coronary artery bypass surgery (CABG) to be superior to percutaneous coronary intervention with respect to long-term mortality and morbidity from myocardial infarction within specific high-risk cohorts. The purpose of this study was to analyze the spatial distribution of coronary artery bypass graft anastomoses relative to acute thromboses in native coronary arteries. We hypothesized that insertion sites of bypass grafts are located distal to sites of acute thrombosis and consequently decrease cardiac morbidity and mortality associated with plaque rupture. We analyzed 168 patients with prior CABG and 208 patients with ST-segment elevation myocardial infarctions (STEMI) presenting to the Brigham and Women's Hospital who underwent coronary angiography. We constructed a spatial map of the coronary arterial bypass graft insertion sites and compared these locations to sites of acute thrombosis leading to STEMI. Graft insertion sites were consistently located distal to acute thrombosis sites (left anterior descending artery median graft insertion versus median thrombosis site = 72 versus 34 mm, right coronary artery 91 versus 42 mm, left circumflex artery 44 versus 37 mm). Greater than 97% of thrombosis sites were located proximal to 75% of graft insertion sites. Coronary arterial bypass grafts provide the coverage of anatomic zones at risk for STEMI. The superior performance of CABG in high risk patients may be attributed to targeting of proximal coronary locations where thrombosis risk is clustered.

Prospective Electrocardiogram-Gated Axial 64-Detector Computed Tomographic Angiography vs Retrospective Gated Helical Technique to Assess Coronary Artery Bypass Graft Anastomosis: - Comparison of Image Quality and Patient Radiation Dose -

In the present study the effective dose and image quality at distal anastomoses were retrospectively compared between prospective electrocardiogram (ECG)-gated axial and retrospective ECG-gated helical techniques on 64-detector computed tomographic (CT) angiography following coronary artery bypass graft surgery. Following bypass surgery, 52 patients with a heart rate <65 beats/min underwent CT angiography: 26 patients each with prospective and retrospective ECG gating techniques. The effective dose was compared between the 2 groups using a 4-point scale (4, excellent; 1, poor) to grade the quality of curved multiplanar reformation images at distal anastomoses. Patient characteristics of the 2 groups were well matched, and the same CT scan parameters were used for both, except for the interval between surgery and CT examination, tube current, and image noise index. Image quality scores did not differ significantly (3.26+/-0.95 vs 3.35+/-0.87; P=0.63), but the effective dose was significantly lower in the prospective (7.3+/-1.8 mSv) than in the retrospective gating group (23.6+/-4.5 mSv) (P<0.0001). Following bypass surgery, 64-detector CT angiography using prospective ECG gating is superior to retrospective gating in limiting the radiation dose and maintaining the image quality of distal anastomoses.

Interrupted distal anastomosis: the interrupted “porcupine” technique

The distal coronary artery bypass graft anastomosis created by an interrupted technique using nitinol clips is likely superior to that created with continuous suture because surgeons place clips with optimal visualization, and the anastomosis exhibits optimal compliance and cannot become a “purse-string” once constructed. Skillful use of the clips allows the surgeon to work in the ever more cramped quarters of the minithoracotomy or minimally invasive incision. Anastomosing vessels without knot tying is a valuable practice in the application of remote and robotic surgeries.

An automatic sutureless coronary anastomotic device: initial results of an animal study.

The efficacy and long-term patency of a new distal anastomotic device (DAD) for the creation of rapid, sutureless end-to-side venous or arterial coronary artery bypass graft anastomoses were tested in a sheep model. The DAD was used on the beating hearts of 34 sheep to create 20 anastomoses between saphenous veins (n = 9) or internal mammary arteries (n = 11) and various coronary arteries. Fourteen conventional hand-sutured anastomoses (7 veins; 7 internal mammary arteries) served as controls. The sheep were sacrificed 1 day, 1 week, and 1, 3, and 6 months after surgery. The immediate patencies of all anastomoses were proven by the rates and pattern of flow. There were no significant differences between the DAD and suture anastomosis groups in presacrifice pulsatility index and occlusion rate. The histomorphometric studies showed complete intimal bridging over the DAD with no significant differences between DAD and suture anastomoses with respect to tissue response, mural injury, inflammation, and adventitial fibrosis. The DAD enables the creation of rapid, efficient, and sutureless venous or arterial coronary anastomoses. The long-term results of histomorphometric studies show that the results with the DAD are comparable with those of conventional hand-sutured anastomoses.

Two generations of the St. Jude Medical ATG coronary connector systems for coronary artery anastomoses in coronary artery bypass grafting

Background In the past, coronary anastomoses have been performed using running and, occasionally, interrupted non-resorbable sutures. Recently, special interest has developed in mechanical anastomotic devices to facilitate minimal invasive techniques or limited access surgery. The experience with two series of patients undergoing coronary artery bypass grafting (CABG) using the St. Jude Medical ATG coronary connector systems (investigational stainless steel device, not yet commercially available) for vein-to–coronary artery anastomoses is reported here. Methods Between November 2000 and April 2002, we evaluated two generations of distal coronary connector systems in 19 patients who were scheduled for multivessel CABG. One vein graft–to–coronary artery anastomosis per patient was performed with a stainless steel mechanical connector, in an ongoing investigational study. Although these two generations of the St. Jude Medical ATG coronary connectors have the same underlying construction, somewhat cumbersome loading of the first-generation system led to simplification of the second-generation system, which is currently evaluated. Results With the first generation of distal connector, hemostasis was instantaneous in all cases, and all anastomoses were patent at the end of the procedure. However, retrograde flow to the native coronary artery was restricted in 1 patient. The connector was removed, and the anastomosis was performed with a running suture at the same site. Three-month angiography or magnetic resonance imaging angiography was available in 11 patients with 10 patent connector grafts. With the second-generation connectors one of five had to be removed because of leakage, and the anastomosis could be sutured at the same site. The other four connector anastomoses were patent and hemostatic at the end of the procedure. Conclusions The St. Jude Medical ATG coronary connector system is an effective device for sutureless vein graft to coronary artery anastomoses in CABG. The second-generation system presents a further development eliminating some drawbacks of the first generation such as cumbersome, time-consuming loading as well as suitability for smaller coronary arteries. These connectors allow construction of geometrically round anastomoses and theoretically may also be suitable for sequential anastomoses. After tremendous research and development efforts, an optimized mechanical connection system for small vessel anastomoses has been introduced into clinical investigation. This represents a major step in the era of sutureless vascular connections in cardiac surgery.

First Clinical Results With a New Mechanical Connector for Distal Coronary Artery Anastomoses in CABG

Coronary anastomoses are currently primarily carried out with the use of running nonabsorbable sutures. Recently, a renewed interest has developed for facilitated mechanical anastomotic devices especially for minimal invasive techniques or limited access surgery. The initial experience with the first successful creation of mechanical vein-to-coronary artery anastomoses in humans is reported. Between November 2000 and June 2001, 14 patients scheduled for multivessel coronary artery bypass grafting (CABG) procedure were investigated. One vein graft-to-coronary artery anastomosis per patient was performed with the St. Jude Medical ATG Symmetry coronary connector system (stainless steel investigational device, not yet commercially available). We evaluated the overall performance of the device. Intraoperative flow measurements of the grafts using transit time methods were measured. A postoperative angiographic control was performed immediately after the procedure in all patients. Hemostasis was instantaneous in all cases and all anastomoses (mechanical n=14, sutured n=40) were patent. Mean intraoperative flow measurements for the mechanical anastomosed vein grafts was 75+/-25 mL/min. Three month angiogram or MRI angiography is available to date in 11 patients. Ten connector grafts were patent and 1 was occluded. There were no cardiac-related adverse events or return of angina; exercise tolerance tests and stress electrocardiograms were normal in all patients. The St. Jude Medical ATG Symmetry coronary connector system is a new device for sutureless distal vein graft-to-coronary artery anastomoses in CABG. This system allows the construction of geometrically perfect anastomoses. This technology represents a further step in a new era of sutureless anastomoses in cardiac surgery.

Minimizing aortic manipulation during OPCAB using the symmetry aortic connector system for proximal vein graft anastomoses

Background. Since minimal invasive techniques have become increasingly common in coronary artery bypass grafting (CABG), there has been renewed interest in facilitated mechanical anastomoses devices that might have the potential of replacing the standard suturing techniques in vascular anastomoses. We report our initial experience with the successful creation of mechanical proximal vein graft anastomoses in off-pump coronary artery bypass operations. Methods. From August to December 2000, we investigated the first 20 consecutive patients who underwent CABG on the beating heart without extracorporeal circulation and who received at least one mechanical proximal vein graft anastomosis with the St. Jude Medical Symmetry aortic connector system without side-clamping of the aorta. We evaluated the different components of the system, the feasibility of such anastomoses, and the intraoperative flow measurements of the grafts using transit time methods. Results. A total of 32 proximal vein graft anastomoses were performed with the aortic connector system. Hemostasis was instantaneous in all cases except one, in which the connector was removed and the anastomosis was hand-sewn without complications. All other vein grafts were patent at the end of the procedure; intraoperative flow measurements were 39 ± 25 mL/min for single vein grafts (n = 20) and 69 ± 25 mL/min for sequential grafts (n = 11). Conclusions. The St. Jude Medical Symmetry aortic connector system is a user-friendly, effective, quick, and reliable device for sutureless proximal vein graft anastomosis in CABG. This system allows the construction of uniform and geometrically perfect anastomoses and does not require aortic side-biting. This technology is attractive for all CABG procedures because aortic manipulation is reduced. In off-pump surgical procedures the connector system allows aortic manipulation to be minimized, potentially reducing embolization from aortic wall debris.

A novel organ culture method to study intimal hyperplasia at the site of a coronary artery bypass anastomosis

Background. Intimal hyperplasia or restenosis at the site of a coronary artery bypass anastomosis contributes to early graft failure, and growth factor release in response to construction of the anastomotic site strongly influences this process. Due to the difficulties in studying restenosis after coronary artery bypass graft surgery, we have tested whether an organ culture model we have developed can simulate the early events associated with intimal hyperplasia. Methods. End-to-side anastomosis of porcine radial artery to porcine coronary artery were constructed. The vessels were trimmed and incubated under standard tissue culture conditions for 14 days. Appropriate controls were treated similarly. The vessels were frozen, cryosectioned, and immunostained for the expression of the proliferation marker proliferating cell nuclear antigen (PCNA). A proliferative index (PCNA positive nuclei/total nuclei) was calculated for comparative purposes. Results. Limited PCNA staining was observed in noncultured vessel segments (0.046 ± 0.045). A slight increase in this index was observed in vessels that had been placed into culture without manipulation (0.230 ± 0.141) and in vessels subjected to an arteriotomy (0.462 ± 0.249). However, the most significant increase was obtained after construction of an anastomosis (4.98 ± 6.66). No change in total cell number was evident over the course of the experiment or in relation to the treatment. Conclusions. Culture conditions and incision slightly stimulate cell proliferation in porcine coronary artery segments when compared with basal conditions of a native artery. In contrast, construction of an anastomosis increases proliferation 108-fold. Therefore, surgical manipulation of arterial conduits during construction of an anastomotic site is the primary trigger for intimal hyperplasia, independent of dissection and incision of the vessel. Furthermore, these data indicate the organ culture model we have developed will be useful for examining the cellular and molecular mechanisms that mediate intimal hyperplasia at the site of a coronary artery bypass graft anastomosis.

Sutureless coronary artery bypass with biologic glued anastomoses: Preliminary in vivo and in vitro results

Objective: As heart surgery becomes increasingly focused on minimally invasive techniques, it has become apparent that conventional techniques of anastomosis will need to be severely altered or abandoned. Toward that end, we developed and tested in vitro and in vivo coronary artery bypass graft anastomoses using a biologic glue formulated from bovine albumin and glutaraldehyde. We used a double-balloon catheter as a temporary internal stent to create and seal the anastomosis during gluing. Methods: Initially, anastomoses were made between cryopreserved human saphenous vein segments and coronary arteries in vitro on 12 intact bovine hearts. A total of 42 anastomoses were created with the catheter system introduced into the distal end of the graft, exiting the back wall, and entering the anterior wall of the coronary artery. Two balloons (one in the graft and one in the coronary artery) held the anastomosis stable while the biologic glue was applied externally and allowed to set for 2 minutes. The balloon catheter was then removed from the end of the graft simulating a side-to-side internal thoracic artery anastomosis. After the graft had been flushed to assure distal end patency, the open end of the graft was clipped, turning the anastomosis into an end-to-side graft. A pressure transducer was then attached to the graft and saline solution forcefully infused. Results: All grafts easily held a pressure of 300 mm Hg; 10 grafts were tested up to 560 mm Hg without leaks. Distal and proximal coronary artery patency was checked by examining flow out of the coronary ostia and by cutting arteries distal to the grafts. All anastomoses were patent on being opened and no glue was seen intraluminally. Subsequently, 3 anastomoses of the left internal thoracic artery to the left anterior descending artery have been constructed in goats, with autopsies at 24 hours, 10 months, and 1 year revealing patent anastomoses. Conclusion: A biologic glue and catheter system has been developed that allows a coronary anastomosis with a high bursting strength to be performed. When the system has been further developed and tested, truly minimally invasive heart surgery may be possible. (J Thorac Cardiovasc Surg 2000;120:473-7)

Proximal anastomoses of aortocoronary bypasses. Evaluation with ECG-triggered single-slice computerized tomography

Assessment of coronary artery bypass graft (CABG) patency with computed tomography methods has been demonstrated as an alternative to coronary angiography. The evaluation of the bypass anastomoses is still of limited success. Prospective ECG triggering of conventional CT scanners allows heart phase-triggered single-slice acquisition in the sub-second range. The goal of this study was to evaluate whether the use of ECG triggering can optimize the evaluation of proximal CABG anastomoses. In ten patients after CABG surgery, ECG-triggered CT with thin (2 mm), contiguous slices was performed in the region of the proximal bypass anastomoses in the ascending aorta. The data evaluation was done on axial images and on reconstructed 2D and 3D data sets. The applied technique demonstrated good imaging quality, which allowed evaluation of the CABG anastomoses in all cases. Overall 18 CABG anastomoses could be visualized; 17 anastomoses could be assessed as normal, non-stenotic and patent. ECG-triggered thin-slice CT permits reliable assessment of proximal CABG anastomoses and expands the usage of CT in the evaluation of CABG.

Controlled intermittent asystole: pharmacologic potentiation of vagal-induced asystole

Background. Minimally invasive direct coronary artery bypass graft operations have, to date, displayed a higher rate of early graft failure than conventional coronary artery bypass procedures using extracorporeal technology. Construction of the coronary artery anastomosis on a beating heart versus a quiescent heart is likely an important factor in this difference between the two approaches. Controlled intermittent asystole induced by vagal stimulation to give transient nonchemically induced asystole for brief intervals sufficient for placement of coronary artery sutures might improve the precision of minimally invasive direct coronary artery bypass graft anastomoses and reduce graft failure while increasing the technical ease of operation. Methods. The feasibility of producing transient, reversible asystole with combined vagus nerve stimulation and treatment with a pharmacologic regimen of (1) an acetylcholinesterase inhibitor (pyridostigmine, 0.5 mg/kg), (2) a β-adrenergic receptor blocker (propranolol, 80 μg/kg), and (3) a calcium-channel blocker (verapamil, 50 μg/kg) was studied in a sheep model. Seven animals underwent right vagus nerve stimulation in two modes: (1) a single continuous 60-second impulse and (2) multiple sequential 15-second impulses. Results. Vagal stimulation alone achieved bradycardia without consistent and reproducible cardiac arrest. After drug administration 6 animals displayed significant potentiation of vagal-induced asystole in the 60-second stimulation protocol (1.6 ± 0.9 seconds non–drug-treated versus 52.0 ± 5.6 seconds drug-treated; p < 0.05). In the sequential 15-second impulse protocol after drug treatment, 6 animals achieved consistent, escape-free asystole during five to six sequential 15-second stimulations versus a brief pause and bradycardia produced without drug treatment. Conclusions. Increased acetylcholine activity by acetylcholinesterase inhibition and prevention of electromechanical escape activity by β-adrenergic receptor and calcium-channel blockade during vagal stimulation produced a marked potentiation of vagal-induced asystole and a means of achieving controlled intermittent asystole. Controlled intermittent asystole achieved by pharmacologic potentiation of vagal-induced asystole may be a useful technique for enhancing technical ease in minimally invasive direct coronary artery bypass graft operations.

Intraoperative evaluation of coronary artery bypass graft anastomoses with high-frequency epicardial echocardiography: experimental validation and initial patient studies.

There is currently no accepted approach for intraoperative evaluation of the technical adequacy of coronary artery bypass graft anastomoses. High-frequency epicardial echocardiography performed intraoperatively could assess coronary artery bypass graft anastomoses by providing on-line short-axis (cross-sectional) and longitudinal two-dimensional images of the vessels. To validate measurements of anastomoses with high-frequency epicardial echocardiography, luminal diameter determined by high-frequency epicardial echocardiography was compared with that determined histologically after perfusion fixation in 12 dogs studied after coronary artery bypass grafting. Technical errors were deliberately created in some grafts. The results of these animal validation studies showed that maximum luminal diameter of the anastomosis by high-frequency epicardial echocardiography correlated well with histologic measurements (r = .92; high-frequency epicardial echocardiography = 0.8 histology + 0.3). All deliberately created technical errors were detected by an independent observer using high-frequency epicardial echocardiography. After completion of the animal studies, we demonstrated the clinical applicability of this approach in 12 patients. Fifteen coronary artery bypass graft anastomoses were examined intraoperatively with high-frequency epicardial echocardiography. The measured maximum luminal diameter of the anastomosis was greater than the maximum luminal diameter of the native artery, as expected, in all end-to-side anastomoses. However, the maximum luminal diameter of the side-to-side anastomoses was equal to or slightly less than that of the native artery. In this initial patient group, minor technical errors were noted in two of 15 graft anastomoses. In conclusion, high-frequency epicardial echocardiography can accurately measure coronary arterial bypass graft anastomoses and has potential for intraoperative detection of technical errors and inadequacies.

Occlusive changes at the coronary artery-bypass graft anastomosis: Morphologic study of 95 grafts

Ninety-five bypass graft anastomoses in 52 patients dying up to 4 years after direct coronary revascularization were studied at autopsy by angiograms and serial histologic sectioning of the graft-artery anastomosis. When new coronary occlusions and narrowings occurred, they were adjacent to either the proximal or distal ends of the anastomosis and were due to compression or loss of circumference of the arterial lumen (40 per cent), thrombus formation (40 per cent), mural dissection of the coronary wall (8 per cent) or the combination of compression and thrombosis (12 per cent). Small coronary artery diameter, local atheromas, and extension of the arteriotomy into a branch vessel were significant factors predisposing to occlusive changes. The findings emphasize the importance of careful artery selection for bypass, the need to avoid local vascular disease and branch-points, and the technical difficulties encountered in the presence of local vascular lesions or small coronary arteries.

Morphology of the coronary artery-bypass graft anastomosis

Morphology of the coronary artery-bypass graft anastomosis